## Lesson Summary

Summary

In this lesson, students will analyze what the Internet is and its basic functionality. Students will learn how the Internet works and how the implementation of the Internet has affected our society. They will discuss the idea of the Internet as a delivery service to get bits from one place to another.

For homework students, should have read and made brief notes on the following sections from the "Blown to Bits" book (Online book link: http://www.bitsbook.com/wp-content/uploads/2008/12/B2B_3.pdf):

• "The Internet as a Communication System"
• "Packet Switching"
• "Core and Edge"
• "Data Format as Public Property"

These sections are on pages 91-92 & 301-303 in the pdf version.

## CSP Objectives

• EU DAT-1 - The way a computer represents data internally is different from the way the data is interpreted and displayed for the user. Programs are used to translate data into a representation more easily understood by people.
• LO DAT-1.A - Explain how data can be represented using bits.
• LO DAT-1.C - For binary numbers: a. Calculate the binary (base 2) equivalent of a positive integer (base 10) and vice versa. b. Compare and order binary numbers.
• EU CSN-1 - Computer systems and networks facilitate how data are transferred.
• LO CSN-1.A - Explain how computing devices work together in a network.
• LO CSN-1.B - Explain how the Internet works.
• LO CSN-1.D - Describe the differences between the Internet and the World Wide Web.
• LO CSN-1.E - For fault-tolerant systems, like the Internet: a. Describe the benefits of fault tolerance. b. Explain how a given system is fault-tolerant. c. Identify vulnerabilities to failure in a system.
• EU IOC-1 - While computing innovations are typically designed to achieve a specific purpose, they may have unintended consequences.
• LO IOC-1.A - Explain how an effect of a computing innovation can be both beneficial and harmful.

## Math Common Core Practice:

• MP3: Construct viable arguments and critique the reasoning of others.
• MP5: Use appropriate tools strategically.
• MP7: Look for and make use of structure.

## Common Core ELA:

• RST 12.2 - Determine central ideas and conclusions in the text
• RST 12.4 - Determine the meaning of symbols, key terms, and other domain-specific words and phrases
• RST 12.6 - Analyze the author's purpose in providing an explanation, describing a procedure
• RST 12.7 - Integrate and evaluate multiple sources of information presented in diverse formats and media
• RST 12.8 - Evaluate the hypotheses, data, analysis, and conclusions in a science or technical text
• RST 12.9 - Synthesize information from a range of sources
• RST 12.10 - Read and comprehend science/technical texts
• WHST 12.6 - Use technology, including the Internet, to produce, publish, and update writing products
• WHST 12.7 - Conduct short as well as more sustained research projects to answer a question
• WHST 12.8 - Gather relevant information from multiple authoritative print and digital sources, using advanced searches effectively; assess the strengths and limitations of each source
• WHST 12.9 - Draw evidence from informational texts to support analysis, reflection, and research

## NGSS Practices:

• 1. Asking questions (for science) and defining problems (for engineering)

## NGSS Content:

• HS-ETS1-1. Analyze a major global challenge to specify qualitative and quantitative criteria and constraints for solutions that account for societal needs and wants.

## Key Concepts

The Internet and the systems built on it have a profound impact on society.

The Internet has many layers and was designed to be fault tolerant with redundant features.

Outcomes

• Students will explain the characteristics of the Internet and how the systems built on it influence their use.
• Students will explain the difference between bandwidth and latency.
• Students will analyze relationships of data transfer over the systems within the Internet.
• Students will synthesize how data transfer and Internet systems are affected by the environment and needs of its users.
• Students will describe how communication paths on the internet are hierarchical and redundant. IP is hierarchical. Routing is fault-tolerant and redundant.

## Essential Questions

• What is the Internet, how is it built, and how does it function?
• What aspects of the Internet’s design and development have helped it scale and flourish?
• How do economic, social, and cultural contexts influence innovation and the use of computing?

## Teacher Resources

Student computer usage for this lesson is: required

Blown to Bits (Abelson, Ledeen, Lewis): http://www.bitsbook.com/

Optional Student Handout: Internet Change Student Handout

The following links provide background on the topics covered in this lesson:

## Getting Started (10 min) - Investigate and Discuss: What is the Internet?

Ask: How does the Internet work?

Journal: Define

• The Internet
• A Web browser

Share student responses and develop class definitions.

Compare student responses to the following.

• Internet: A collection of systems working together to deliver data to the user. Data delivery includes email, video streaming, social media traffic, and cloud file storage and retrieval.
• Web Browser: A software application used to retrieve and display information from the world wide web, which is one part of the Internet.

## Part 1 - Exploration (10 min)

Say: How did the internet and web browsers come about?  The internet wasn't originally intended for everyone.  Originally it was a tool for scientists to communicate.

Show how the Internet has grown from the small ARPANET system to what it is today.

1. View ARPANET image: http://www.policy.hu/inetclass/arpaNet.html (from 1971)
2. Watch the discussion from the Today Show discussion on "What is the Internet?" (2:12 min):https://www.youtube.com/watch?v=95-yZ-31j9A
3. View the image of today's Internet: http://googlemapsmania.blogspot.com/2013/12/mapping-internet-of-things.html Note: zoom in to see the details.  Investigate your local area including your own school, and explore.  Have students find 4 different things with 4 different colors.

## Part 2 - Discussion (10 min)

Show the video Who Invented the Internet and Why through 4:49.

Ask: How is all this interesting and valuable information represented?

Lead students to develop the concept that lower-level abstractions can be combined to make higher-level abstractions such as texting (SMS), email, images, sound or video. (ie: one byte can represent one note, put notes together to make a soundtrack. 6 bytes make 1 color pixel. Put pixels together to make a picture. Put sound and pictures together to make a video)

Ask: who and what was theWorld Wide Web was originally intended for?
Answer: only for rapid and easy exchange of information within the scientific community.

Point out how, like many innovations, it grew beyond the original vision, but because of the limited view of its use in the beginning, there were serious holes in the security design of the system. Other design features, like scalability, have served the system well over many years.

Ask:  How is information retrieved on the Internet?
Answer: Web browsers make requests for image, sound, web page and other files using the http or https protocols.

Requested files are broken into smaller pieces and the transmission of these pieces is done following the TCP/IP protocol.

Discuss the following sections from pages 301-303 in the "Blown to Bits" book. (Online book link: http://www.bitsbook.com/wp-content/uploads/2008/12/B2B_3.pdf):

• "The Internet as a Communication System"
• "Packet Switching"
• "Core and Edge"

## Part 3 - Internet Simulation (15 min)

1. Ask: What happens if one of the computers along the pathway loses power or is overloaded with data traffic? Point out that in case of problems there are many different paths (redundancy) that a message can be routed along and that everything on the internet has its own address (IP address) to be covered in upcoming lessons.
2. Explain that packet transmission rate is measured by "bandwidth" and the time it takes for packets to be delivered is called "latency."
1. Pass a message along one row a single word at a time, and then send it back across the room using multiple rows (paths) at once to demonstrate bandwidth. Measured in bits per second = how many bits arrive.
2. To show latency, have each student pass each packet under their chair before passing it on creating greater latency (delay) to get information from one side of the room to the other. Explain that latency could be caused by a single slow link in the connection or overall slowness.
3. Students read the following articles (both are relatively short) and answer questions after.
4. Latency: http://www.webperformancetoday.com/2012/04/02/latency-101-what-is-latency-and-why-is-it-such-a-big-deal/
• Latency is the delay. How long you have to wait to send or receive.
5. Bandwidth: http://www.coolnerds.com/Newbies/Bandwidth/Bandwidth.htm
• Bandwidth is like the width of a highway, the more lanes you have the more cars can drive on the road at once

# Wrap-up (5 min)

In this activity, students will each share one thing they have learned from this lesson. This can be done in several ways depending on time constraints or disabilities. All students should participate in some way before leaving the classroom.

• Have all students stand. In order to sit back down, students must share one thing they have learned to the class. (This may happen organically, or in a prescribed order.)
• If there is a disabled student for whom the standup/sit activity would not be an option, develop an alternative way to indicate who in the class has answered (such as having them raise their hands).
• If there is a student who has difficulty speaking in front of the class or there isn't sufficient time, hand out index cards on which each student must write what they have learned, to be handed in as an exit ticket to leave the class.

## Guidance for Practice Questions - Question Set 10

Questions in the AP Classroom Question Bank may be used for summative purposes.

Sixty of the 80 questions are restricted to teacher access.  The remaining 20 questions are from public resources.

Questions are identified by their initial phrases.

ASCII is a character-encoding scheme that uses ...

Consider the following numbers. Binary 1100Deci...

## Options for Differentiated Instruction

• Students can share comparisons of assignments in small groups.
• Students can further explore net usage (using http://www.akamai.com/html/technology/dataviz1.html) specifically targeting mobile usage and/or broadband usage by geographical regions. Analyze the differences between these geographical regions of packet usage.

## Formative Assessment

Using a real-time network tool that measures the number of views per minute, students generate a question that can be answered using this tool. They will then collect the data and write a report that answers this question. The report should use current real-time screenshots for data and examples. (Note: Students can possibly start this assignment in class, but will likely need to complete as homework.)

## Summative Assessment

Possible question(s) to use for a future test:

• What is the relationship between bandwidth and latency?
• When using Internet tools to display data, what are some important factors that need to be considered to better understand the information being displayed?

## Lesson Summary

Summary

The Internet is growing to connect to everything we do in our lives. Over the years, it has grown from being a representation of static content to web 2.0: a place where users interact with a collection of users and "things." In this lesson, the students will conceptualize devices that collect data and send it through the Internet.

## CSP Objectives

• EU DAT-1 - The way a computer represents data internally is different from the way the data is interpreted and displayed for the user. Programs are used to translate data into a representation more easily understood by people.
• LO DAT-1.A - Explain how data can be represented using bits.
• EU DAT-2 - Programs can be used to process data, which allows users to discover information and create new knowledge.
• LO DAT-2.C: - Identify the challenges associated with processing data.
• EU CSN-1 - Computer systems and networks facilitate how data are transferred.
• LO CSN-1.A - Explain how computing devices work together in a network.
• LO CSN-1.B - Explain how the Internet works.
• EU IOC-1 - While computing innovations are typically designed to achieve a specific purpose, they may have unintended consequences.
• LO IOC-1.A - Explain how an effect of a computing innovation can be both beneficial and harmful.
• LO IOC-1.B - Explain how a computing innovation can have an impact beyond its intended purpose.
• EU IOC-2 - The use of computing innovations may involve risks to your personal safety and identity.
• LO IOC-2.A - Describe the risks to privacy from collecting and storing personal data on a computer system.

## Common Core ELA:

• RST 12.7 - Integrate and evaluate multiple sources of information presented in diverse formats and media
• WHST 12.1 - Write arguments on discipline specific content
• WHST 12.2 - Write informative/explanatory texts, including the narration of historical events, scientific procedures/experiments, or technical processes
• WHST 12.6 - Use technology, including the Internet, to produce, publish, and update writing products
• WHST 12.9 - Draw evidence from informational texts to support analysis, reflection, and research

## Key Concepts

The Internet is an ever-evolving system of increasing complexity. It has evolved from representing static information to providing interactivity of data between users and objects (things).

Outcomes

• Students will understand the development of the Internet.
• Students will understand how the digital divide is reflected in Internet access.
• Students will understand how devices communicate on the Internet.
• Students will imagine/design things (that don't yet exist) that could connect to the Internet.
• Students will identify how artificial intelligence has enabled innovation but also create additional causes of discrimination.

## Essential Questions

• How can computational models and simulations help generate new understanding and knowledge?
• What is the Internet, how is it built, and how does it function?
• What aspects of the Internet’s design and development have helped it scale and flourish?
• How does computing enhance human communication, interaction, and cognition?
• How does computing enable innovation?
• What are some potential beneficial and harmful effects of computing?
• How do economic, social, and cultural contexts influence innovation and the use of computing?

## Teacher Resources

Student computer usage for this lesson is: optional

Blown to Bits (Abelson, Ledeen, Lewis). Text is free as pdf: http://www.bitsbook.com/

In the Lesson Resources Folder:

• "Commercial Python Project" Project Description Document
• "Commercial Python Project Rubric" Rubric for the Commercial Project

## Getting Started (5 min) - Journal / Discussion

1. In their journals, ask students to identify as many objects in the school as they can that are connected to the Internet (or that would be more useful if they were connected to the Internet).
2. Have students share with a neighbor. Then, communicate through a whip-around or a large group discussion. Generate a list of devices.
3. Optional: Review investigations of Internet usage statistics that the students completed in Lesson 3-1 (particularly useful if the students completed the investigation as homework).

## Part 1 -  (15 min)

Say:  Devices connected to the Internet collect data.  Sometimes those devices and the programs that store and process the data can have applications that the developers did not intend and may be very significant.  For instance, consider this video from CNN about an app called Strava.  https://www.cnn.com/2018/01/28/politics/strava-military-bases-location/index.html  Play the video.(2:12). Have a brief discussion using the following questions as prompts.

• What was the intended purpose of the app?
• What purpose could the app have that the developers never intended.

Say: Data collection is not just from devices people knowingly use but increasingly from things connected to the internet they may not be aware of. Many computing innovations affect people in ways that were not anticipated.

Show the video (no audio except music) on how an average everyday person uses objects connected to the Internet in our current society: https://www.youtube.com/watch?v=ZgWbWCv0J5E  (3:58)

Summary: A day in the life of the Internet of things shows these things connected to the Internet: cell phone, thermostat in the house, car entry system and radio, car GPS intelligently looking for available parking, parking sensors on the ground using mesh networking (short-range connections to a larger deployment system in a central box), a heart rate monitor with results that can be viewed online in real-time, a watch that connects with a cash register/inventory system, a package pickup system that connects with a drone to take the package directly to the customer.

Say: The data collected today is too large to be processed by people.  Two strategies used to analyze large amounts of data are called data mining and artificial intelligence. While both tools regularly find useful results - useful in science and in business - the information obtained may result, in adverse decisions made against individuals or groups.

Students read the May 21, 2019 Guardian article, Facial recognition will soon be everywhere. Are we prepared? (https://www.theguardian.com/commentisfree/2019/may/21/facial-recognition-privacy-prepared-regulation).  As students read, have them prepare to respond to the following prompts.

• Identify an ethical concern or an ethical advantage of near-continuous surveillance supported by the Internet of Things.
• Identify a legal concern or advantage of near-continuous surveillance supported by the Internet of Things.
• Identify how information gathered and evaluated by computers has and can lead to discrimination.

## Part 2 - Internet of Things (10 min)

Say:  Originally people generated the traffic on the internet.  In the future, the vast majority of traffic on the internet will be generated by things.

Show this video about how data is generated by devices connected online:

Ask students if there were any objects that they did not think about earlier that are connected to the Internet. Adjust the list as needed. Analyze which devices would continue to be a high priority or useful if the ability to communicate on the Internet was suddenly diminished by an event like a hurricane or earthquake.

Journal. Pair and share.

1. What systems on the Internet are most critical today?
2. What systems will be the most important in the future?

## Part 3 (15 min)

With a partner, imagine a device that might someday be a part of the "Internet of Things," but currently does not exist. An example might be a shoe that has its own wireless acquired IP address and keeps track of how many steps one takes each day. (Note: This may already exist.)

As a small group, the students should create a document answering the following questions:

1. What is the purpose of this device?
2. What data will your device collect?
3. What sensors will it use?
4. What are the risks to the privacy of the data stored on the device?

This document should also include a sketch of the device.

## Wrap Up (5 min)

Students display a thumbs up or thumbs down to this question: Did this lesson help you comprehend the concept of the Internet as an entity that is comprised of both people (users) and objects or machines?

## Homework

Read Blown to Bits (Pg 303 - 306) -  IP Addresses - stop at "The Key to It All: Passing Packets."

## Getting Started (5 min) - Journal

Say:  Today we will think about the future of the internet. The internet was designed to be scalable or to be adaptable to serve increasing demands.  This ability to adapt to meet increases in demand, or scalability, was a design goal of the original internet.  It was not part of the internet's original design to serve commercial needs.
Ask students to respond to these questions about how commercial needs have impacted them.

1. How much advertising is imbedded in apps and web pages?
2. Does everyone see the same ads?

## Guided Activities (40 min)

Say:  Revenue from advertising is used to pay many of the expenses for content and services delivered by the internet.  Businesses use data they collect about individuals to put them in a group and to target them for ads.  Individuals and businesses both can benefit from seeing advertisements that most interest them.

Ask:  Think about how individuals and groups could be harmed by the targeting of ads.  Have a brief discussion about the possible harms.  Be sure to address the three bullet points below.

• How might an individual be harmed?
• What groups might be harmed?
• How might one or more of these groups be harmed?

## Creative Writing Project

Students create a story to summarize what they have learned about what the internet is and what they expect it to become in the future.  The summary should include what impact the internet has already had, what impacts they think it might be intended to have in the future and what unintended impacts it might have.

Say:  As you think about the future of the internet remember that the protocols it uses are open to everyone so technologies not yet developed can be adapted to use them.  In this project, you are asked to envision what one of these technologies might be.

Students may present the story in written or other formats.

## Guidance for Practice Questions - Question Set 11

Questions in the AP Classroom Question Bank may be used for summative purposes.

Sixty of the 80 questions are restricted to teacher access.  The remaining 20 questions are from public resources.

Questions are identified by their initial phrases.

Two computers are built by different manufactur...

Which of the following best explains what happens

### Optional - Python Programming Project

Using the document in the Lesson Resources folder called "Commercial Python Project", assign students the project to explore more about the "Internet of Things" and think about what the future of the "Internet of Things" might be.  In the project, students consider creating their own product commercial template. Consider adding the requirement that their program includes conditional statements. Extra time will be needed.

The rubric for this project can also be found in the Lesson Resources Folder

## Options for Differentiated Instruction

Ask students to think about and document how their selected device may have an impact on our daily lives. Could their be any controversy associated with their device or the use of their device? If so, what is that controversy? Students should document their opinions and/or findings.

When selecting the pairs, aim for diversity of background, so the students learn how others view technology.

## Formative Assessment

With a partner, imagine a device that might someday be part of the Internet of Things, but currently does not exist.

As a group, the students should submit a document answering the following questions:

• What is the purpose of this device?
• What data will your device collect?
• What sensors will it use?
• Who will make use of the data?
• What will be the range of values needed to store the data?

This document should also include a sketch of the device.

## Summative Assessment

How does the Internet effectively connect devices and networks?

How do devices and networks that make up the Internet communicate?

## Lesson Summary

Summary

This lesson delves deeper into the structure of the Internet and routing protocols.  Students will explore the necessity of redundancy by using packets to transmit sections of data.  They will then discuss standards for packets and routing.  The class will simulate a network in which each student is a node through which they will send email packages from one node to another.

Outcomes

• Students will explain how the Internet moves data from one place to another using routers.
• Students will understand how data is encoded on the Internet.
• Students will explain how large amounts of data are managed on the Internet.
• Students will be able to define protocol and TCP/IP

Overview

1. Getting Started (10 min)
2. Activity Pt A: Simulation of packet transfer (10 min)
3. Activity Pt B: Simulation including lost packets (10 min)
4. Discussion (15 min)
5. Wrap Up (5 min)

## CSP Objectives

• EU CSN-1 - Computer systems and networks facilitate how data are transferred.
• LO CSN-1.A - Explain how computing devices work together in a network.
• LO CSN-1.B - Explain how the Internet works.
• LO CSN-1.C - Explain how data are sent through the Internet via packets.
• LO CSN-1.D - Describe the differences between the Internet and the World Wide Web.
• LO CSN-1.E - For fault-tolerant systems, like the Internet: a. Describe the benefits of fault tolerance. b. Explain how a given system is fault-tolerant. c. Identify vulnerabilities to failure in a system.

## Math Common Core Practice:

• MP3: Construct viable arguments and critique the reasoning of others.
• MP6: Attend to precision.
• MP7: Look for and make use of structure.

## NGSS Practices:

• 1. Asking questions (for science) and defining problems (for engineering)
• 2. Developing and using models
• 3. Planning and carrying out investigations
• 8. Obtaining, evaluation, and communicating information

## Key Concepts

Students will be able to:

• Create a list of aspects of the Internet’s design that have helped it scale and flourish, and articulate how these aspects contribute to its growth.
• Diagram the path of an email as it travels from one Internet user to another.
• Explain why it makes sense to send data in multiple packets rather than all together.

## Essential Questions

• What is the Internet, how is it built, and how does it function?
• What aspects of the Internet’s design and development have helped it scale and flourish?
• How is redundancy built into the Internet?
• Who is in charge of the Internet?

## Teacher Resources

Student computer usage for this lesson is: none

1. Materials required

• Post-It Notes - each student needs 10-20 Post-Its
• Desks/Tables should be moved to form a grid such as a 6 by 6 grid.

2. Copies to make

• Teacher IP Address Locations - One for the teacher.
• Student IP worksheet - One per student. Either hand these out after students are seated, or put one at each desk prior to the start of class. Make sure that the layout of the worksheets matches the layout of the Teacher IP Address Locations.

3. Digital resources (check for access)

4. Required background knowledge

## Getting Started (10 min)

### Journal

Prompt students to respond in their journals to one or more of these questions:

• When you type the name of a website (URL) into your browser, how does the browser know how to find that website?
• How does data get from one point to another on the Internet?
• Who is in charge of the Internet.

Discussion: Invite students to share their journal entries.  The class should come to the general consensus that while their computer doesn’t know where to find everything on the Internet, it is able to pass information or requests from one location to another.

• As an analogy, describe the theory behind "six degrees of separation."  This theory states that if person A is told the name of one other person in the world (person B), then through no more than five individuals, one of whom is a personal acquaintance, person A will be able to contact person B. The choice of that personal acquaintance is key:  If you’re trying to find someone in France, it is better to ask a friend in France to find person B than to ask your neighbor (unless you already know that your neighbor has strong connections with the people in France near person B).  While the theory isn't precisely true, it is true that most real-world networks tend to have "hubs" (highly connected nodes (people who know many other people, or Internet nodes that are connected to many other nodes) and "spokes" (connections from hubs to individuals or nodes who are less well connected).
• The internet is not run by any government or business but rather is run by the IETF. https://www.ietf.org/ The IETF's mission is "to make the Internet work better," but it is the Internet Engineering Task Force, so this means: make the Internet work better from an engineering point of view, not politics or government.

## Activity Part A: Simulation of Packet Transfer (10 min)

Transition Remark:  Previously, we looked at the general structure of the Internet and how it works.  Today, we will look more closely at the process of sending information between two locations using the Internet.  Let's see what this looks like through a video(Code.org packets) or World of Science video. (After video) We are going to simulate this same action by sending packets of information to each other without leaving our seats.

Introduction:

• Tell students that they will use rules, just like the Internet, called protocols.  Compare the process followed by the Internet to get information from one place to another to the algorithms that they created previously (inputs of some type are given to the algorithm; it performs the same process on any information given; and then it produces a result).  The protocols are applied to every packet of information that is sent. For this simulation, our protocol will have the structure “Recipient IP:____, part # of total, Sender IP:_____ “
• On the Internet, the addresses are called Internet Protocol (IP) addresses.  These addresses are made up of three numbers, and often correlate to your geographical location.   Today, you will each be given an IP address consisting of three letters.  I have determined this address through your geographical location in the room. (As students participate in this activity, they will see the use of hierarchy.  Most of their packets that begin with the same letter will go to the same general region, although there are a few that break this pattern.)
• Display the definition of TCP/IP (http://www.computerhope.com/jargon/t/tcpip.htm). Explain that there are many layers of protocols on the Internet from those that control hardware up to those that interact with application programs. Show the table of protocol hierarchy. (https://www.iplocation.net/tcp-ip)
• Your goal is to send a letter that I will hand out to the correct IP address, but here is the catch:  Computers do not store the location of every IP address in the world.  They are given the IP addresses of other coputers that are connected to them.  Thus, you may only communicate with your neighbors to tell them your IP address. This must be done silently. (You may show them your IP address from your paper, or write it on a Post-It.)
• You can also ask your neighbors (via Post-It note) who they have access to, and your neighbors can ask the same question of their neighbors.  In this way, you may find that you have access to someone else, but not know the route that the package must go to get there.
• On the back of your IP card, you have a table, which you should use to record how to get messages between yourself and different students in the class.
• Example: We are going to attempt to transmit a package from B.B.A to C.B.D.
• Student B.B.A - ask neighbors if they are C.B.D, or can get there.
• This request should propagate through students until someone has found C.B.D.
• C.B.D responds to their neighbor, who tells the neighbor who asked.  This repetition should continue until the news has reached the original sender.  B.B.A gives their message to the neighbor with the connection, and records on their paper who they went through to make the connection.
• The message is passed on to C.B.D, who opens it, and reads it.
• Hand each student paper to serve as "packets," and allow them to send messages to one another.  Make sure that they use the correct protocol on each message.
• Allow students to send packets that request information (what is your favorite ice cream, do you have siblings, etc.), and make sure that return packets are addressed and sent.

## Activity Part B (10 min)

Transition Remark: Our simulation of the protocol system on the Internet has been relatively tame.  In reality, it doesn’t always work this nicely.  Sometimes packets are lost; not all the information you want to transmit fits in one packet; or some routers are unable to keep working.  Fortunately, the Internet is full of redundancy that allows it to keep working even if some parts fail to work, and we can send large data sets through multiple packets.  We’re going to run our simulation again, but this time living in the "real world."

• Allow students to send messages to one another, but this time, as students transmit packets, mix them up a bit to simulate lost packets or unreadable data.
• Require students to find information from one another, but give them a character limit (like a text or tweet) for each packet that requires them to use multiple requests to send the information.
• Give IP cards some identifiable characteristic (print them on different color paper, put a sticker in the corner, etc.), and tell students with a particular characteristic that they are unable to connect to the network.  Ask the remainder of the class to try to send messages without them.  This will simulate the power of redundancy.

Discussion: How does redundancy of routers contribute to Internet fault tolerance?

• Some of your packets are getting lost!  Sometimes this occurs in the middle of a multi-packet message. This is very frustrating, especially when we do not know whether all of our packets were received.  How could we make our protocol system better in order for our Internet to run more smoothly?
• This discussion should end with students deciding it would be nice to have a reply message such as "I got it!" with the number the packets that went together (1 of 3). The teacher should allow students to come to this conclusion on their own, but you may need to push them in this direction.

## Discussion (10 min)

Transition Remark: We just participated in a simulation that allowed us to become nodes within the Internet.  By filling out the back side of your IP worksheet, each of you was essentially becoming a router.  Each routers contains a configuration table with information that it can use to send packets to the correct location.

Discussion:

• What is the role of the IP address for each device on the Internet?
• How does redundancy of routers contribute to the Internet’s ability to scale to more connections?
• Students will need to extrapolate from their understanding of the simulation to answer this question.

Conclusion: This information should be written in the student's journal.

• We have simulated some protocols used to transfer information across the Internet.  However, there are other protocols that are necessary for sharing information and communicating between browsers and servers on the Web.  These include information exchange (HTTP protocols) and secure sockets layer/transportation layer security (SSL/TLS).

## Wrap Up (5 min)

Reflection: This may be completed as an exit ticket for formative assessment or in student journals.

• In the activity, what happened when you tried to send out packets of information?
• What worked in the activity and what did not work?
• Make comparisons between what happened in the activity and what actually happens as data moves on the Internet.

## Guidance for Practice Questions - Question Set 12

Questions in the AP Classroom Question Bank may be used for summative purposes.

Sixty of the 80 questions are restricted to teacher access.  The remaining 20 questions are from public resources.

Questions are identified by their initial phrases.

A user enters a Web address in a browser, and a...

What is the minimum number of connections that ...

## Options for Differentiated Instruction

### Routers

• Research how routers use IP addresses to know where to send packets of information. Write one paragraph, a poem or rap, or create a diagram to communicate what you learned on the topic.

### Traceroute

• Use a Traceroute utility to trace the path that a packet takes to get to your computer. Create a flowchart/path diagram to record what you learned.

## Formative Assessment

Assessment will occur informally through the discussion questions:

• What is the role of the IP address for each device on the Internet?
• How does redundancy of routers contribute to the Internet's ability to scale to more connections?

Reflection questions for journal:

• In the activity, what happened when you tried to send out packets of information?
• What worked in the activity and what did not?
• Make comparisons between what happened in the activity and what actually happens as data moves on the Internet.

## Summative Assessment

Assessment Questions:

Explain the role of the Internet Protocol address for each device on the Internet.

Why is the assignment of an IP address critical to connecting a device to the Internet?

How does Internet router redundancy contribute to Internet fault tolerance?

How does redundancy of routers contribute to the Internet's ability to scale to more connections?

Explain how relatively small packets are used to transmit large files on the Internet and identify what information each packet must possess.

Identify a standard protocol for Internet packet communication.

## Lesson Summary

Pre-lesson Preparation

Students must complete the pre-reading assignment: Blown to Bits (pages 303 - 306 in the PDF). They should read the sections about DNS, Protocols, and IP Addresses.

Summary

The purpose of the Domain Name System is to resolve domain names to IP address for computers on the Internet.

For the next two lessons, students will investigate the workings of the Domain Name System (DNS). They will then design and enact a simulation of DNS.  Students will use their simulation to request and receive web pages, implement DNS caching, and investigate DNS poisoning.

Outcomes

• Explain the abstractions in the Internet and how DNS supports Internet functions.
• Explain the hierarchical characteristics of DNS.
• Explain how IPv4 and IPv6 addressing are used to identify and connect computers on the Internet.

Overview

Session 1 - Introduce DNS

1. Lesson Introduction (5 min) - Introduce DNS.
2. Guided Activity (40 min) - Students investigate elements of DNS and sketch its components.
3. Closing (5 min) - Watch improvisation video.

Session 2 - Create DNS Improvisation

1. Introduce Simulation/Improvisation (5 min).
2. Guided Activity (40 min) - The roles and scripts for the next lesson’s activity are set up.
3. Closing (5 min) - Journaling about the characteristics of DNS and the Internet.

## CSP Objectives

• EU CRD-1 - Incorporating multiple perspectives through collaboration improves computing innovations as they are developed.
• LO CRD-1.A - Explain how computing innovations are improved through collaboration.
• EU CRD-2 - Developers create and innovate using an iterative design process that is user-focused, that incorporates implementation/feedback cycles, and that leaves ample room for experimentation and risk-taking.
• LO CRD-2.A - Describe the purpose of a computing innovation.
• EU CSN-1 - Computer systems and networks facilitate how data are transferred.
• LO CSN-1.A - Explain how computing devices work together in a network.
• LO CSN-1.B - Explain how the Internet works.
• LO CSN-1.C - Explain how data are sent through the Internet via packets.
• LO CSN-1.D - Describe the differences between the Internet and the World Wide Web.

## Math Common Core Practice:

• MP5: Use appropriate tools strategically.
• MP6: Attend to precision.
• MP7: Look for and make use of structure.

## Common Core ELA:

• RST 12.2 - Determine central ideas and conclusions in the text
• RST 12.4 - Determine the meaning of symbols, key terms, and other domain-specific words and phrases
• RST 12.10 - Read and comprehend science/technical texts
• WHST 12.6 - Use technology, including the Internet, to produce, publish, and update writing products
• WHST 12.9 - Draw evidence from informational texts to support analysis, reflection, and research

## NGSS Practices:

• 1. Asking questions (for science) and defining problems (for engineering)
• 2. Developing and using models
• 3. Planning and carrying out investigations

## Key Concepts

Students describe characteristics of the Internet that influence the systems built on it.

Students explain how computers can be used to get a web page from a new web server.

Students work as part of a collaborative group using effective communication to accomplish a task.

## Essential Questions

• What is the Internet, how is it built, and how does it function?
• What aspects of the Internet’s design and development have helped it scale and flourish?

## Teacher Resources

Student computer usage for this lesson is: required

Blown to Bits (either electronic or hard copy)

Excel or similar software

"DNSWorksheet" document and "Favorite Domains (Sample List)" spreadsheet in lesson resources folder

https://studio.code.org/s/netsim Code Studio Internet Simulator

Student friendly explanation of DNS  https://studio.code.org/s/netsim

# Getting Started (5 min) - Introduction of DNS

1. Students will watch this video https://www.youtube.com/watch?v=72snZctFFtA from 0:47 to 3:22 to introduce the function of DNS.
2. Students should consider the video and the pre-lesson reading to answer the following question: "What is the purpose of the Domain Name System?"
3. After the students have finished journaling, the teacher should give these explanations to clarify DNS and further set up the lesson:
• The purpose of DNS is to resolve domain names to IP address for computers on the Internet.
• Our purpose as a class is to understand what DNS means, how it works, what benefits it provides, and some challenges it faces.

# Guided Activity (40 min)

## Part 1 (30 min) - Investigation

Version 1 - If students have access to the system console window, use it to complete the following steps.

Directions for Host Configuration and DNS in Action Using the Console Window:

1. Console Based Use: (cmd prompt)
3. Find the IP address of the default gateway (ipconfig)
4. Find the physical address of the default gateway (arp –a)
5. Resolve domain names: (nslookup)
• umbc.edu
• domain.name
1. Domain names recently resolved: View the HOST DNS cache (ipconfig /displaydns)
2. Unknown domain names: Find the IP address of the local DNS server: (ipconfig /all)

Version 2 - If the Console is blocked for your students, you can still demonstrate most of the console commands on your computer.  If it is blocked for you as well, use a web site such as  http://pingtool.org  and the prompts below.

Note: If the Console is blocked, students will need a way to obtain unique IP addresses.  A document named "DHCP Simulator" (in the lesson folder) contains 30 unique IP formatted addresses.  Print and cut out the blocks and allow a student dubbed DHCP to give them out at random.

Directions for Host Configuration and DNS in Action Activity Without the Console Window:

1. Find your host’s IP address: (just search for get ip address).  Survey student results and explain that the values are the often the same because the network uses one computer to make connection outside the local network.
2. Watch the first 40 seconds of DNS Cache Poisoning (https://www.youtube.com/watch?v=1d1tUefYn4U)
3. Use traceroute to find the number of routers (hops) involved in getting to apcsprinciples.org.
4. Resolve domain names: (nslookup)
• umbc.edu
• domain.name
5. Domain names already resolved: Copy the IP addresses to a browser’s web address bar and visit two of the domains from number 4.
6. Unknown domain names: Review the traceroute results to each domain.  What is the IP address of the default gateway?

During the investigation, students should answer the following questions in their journal:

Journal Questions for Version 1:

Students should attempt to answer these questions based on the previous activity:

1. How do you access a command prompt?
2. What console command do we use to find our IP address and the IP address of the default gateway?
3. How can we find the physical address of the default gateway?
4. How do Internet bound packets get to the default gateway?
5. How can we look up (resolve) unknown IP addresses from the console?
6. How can we see a list of the domain names and IP address already resolved by our host computer?
7. How does your computer resolve unknown domain names into their addresses?
8. The number of devices that could use an IP address has grown so fast that a new protocol (IPv6) has been established to handle routing of many more devices. How do you think IP addresses have changed?

1. In Windows, click Start>run then type cmd.
2. At a console prompt, type ipconfig.
3. At a console prompt, arp -a.
4. IP packets are sent inside physically addressed frames.
5. Use nslookup followed by the domain name.
6. At a console prompt, ipconfig /displaydns
7. The computer obtains the IP address by requesting it from the local DNS server.
8. The world officially ran out of the 4.3 billion available IPv4 addresses in February 2011. Yet, hundreds of millions of people and devices are coming online. IPv6 is what will allow this, providing enough addresses (2128 to be exact) for everyone and all of their various devices. from the Internet Society http://www.internetsociety.org/what-we-do/internet-technology-matters/ipv6 )

Journal Questions for Version 2:

Students should attempt to answer these questions based on the previous activity:

1. The Console is just one tool that can be used to find a computer's actual IP address.  How is the Console accessed on your computer at home, if you have one?
2. Why does pingtool.org not give us our real IP address?
3. What is the role of the local DNS server?
4. What is the purpose of the routers on the Internet?
5. Why did domain.name not resolve to an IP address?
6. What do we call the list of domain names and IP addresses already resolved by our host computer?
7. How does a computer resolve unknown domain names into their addresses?

## Part 2 (5 min) - Video

1. Students will watch this video https://www.youtube.com/watch?v=72snZctFFtA  to show the function of DNS.
2. Give students a copy of the DNS worksheet.

## Closing Activity (5 min) - Journal

Have students pick one or more of the following questions to answer in their journals:

• Just as the original Internet developers did, we are using a trust model - assuming everyone is cooperating.  Why do you think we used a trust model?
• The Internet’s end-to-end architecture makes connecting to it simple.  Why do you think an end-to-end architecture encourages invention and innovation of Internet-based systems?

# Optional Activities:

## Diagram (10 min)

Put the following list of DNS and other devices on the board.  As a class, students are to create a diagram of the way devices 1 – 5 interact to resolve domain names (similar to the last picture in the overview.)  Have students draw the picture on the board and agree that it is correct before they write it in their journals.

1. Host
2. Local DNS
3. Root
4. Top Level Domain
5. Authoritative Name
6. Web Server
7. Router

## All the world is a stage, and all the men and women merely players (55 minutes)

Getting Started/Introducing Activity (5 min)

The teacher will explain the following activity to the students:

1. We are going to simulate the function of DNS as used to obtain web pages on the Internet, creating a sort of improvisational play.
2. Just as the original developers did, we will use a trust model:
• Assume everyone is cooperating.
• Use an “end-to-end architecture” that keeps the center of our network as simple as possible.
• (Have students record both of these characteristics of the Internet in their journals.)
3. Together with DNS, web servers, and Internet routers, students playing the role of each device will request, resolve, and deliver web pages.
4. Along the way, we will likely run into several problems and failures (learning opportunities).  As we do, we will resolve them together and record our insights in our journals.

Show DNS explained (https://www.youtube.com/watch?v=72snZctFFtA) 3:20 - 5:39.

# Guided Activity (40 min) - Improvisation Activity

## Part 1 (30 min) - DNS Device Roles

1. Have students watch "The Way of Improvisation" https://www.youtube.com/watch?v=MUO-pWJ0riQ
2. In small “author” groups, have students prepare scripts for students who will play a device.
• Each group creates a card or page for their device.
• One side of the page contains the device name and an explanation of its role.  (The explanation is to be brief – fewer than 25 words but enough to give a non-expert the general idea of the role of the device.)
• The other side of the paper contains a more detailed explanation of the service the device provides, including the devices with which it communicates, a list of the data required for the server to function, and an explanation of how the data is initially acquired.
3. Each group should print one draft copy of their scripts.  Students share (rotate) their device scripts with another group.
4. Each group makes constructive criticisms and returns scripts to their authors.  (If time permits, you may want to repeat this round.)  Review groupwork norms that encourage respect of multiple perspectives.
5. "Author" groups make revisions and print 4 copies of each device page.  (Use front and back of the paper if possible.)
6. Collect these and keep them sorted by device.

## Part 2 (10 min) - Web Servers

Teachers will explain that the Internet is much bigger than the Web, but for our simulation purposes, we will only be trying to access web pages from web servers.

1. Depending on the size of the class, pick two or three domain names to simulate, such as .com and .net. Select two domains from each top-level domain.  (For instance, for .com, you might select google.com and amazon.com.)
2. Divide the class into groups such as the "google group", the "amazon group", and the other subdomains selected.
3. Each student in each group finds a unique page from their second-level domain and prints two copies of the first page of the web page each student selects.
4. Have students write a one-word title for their page on the top of the paper and submit it to you, placing the pages in piles by subdomain.

## Guidance for Practice Questions - Question Set 13

Questions in the AP Classroom Question Bank may be used for summative purposes.

Sixty of the 80 questions are restricted to teacher access.  The remaining 20 questions are from public resources.

Questions are identified by their initial phrases.

According to the domain name system (DNS), whic...

What is the minimum number of connections that ...

Which of the following is a characteristic of the

## Options for Differentiated Instruction

When pairing up students in "Think - Pair - Share," use a random generator such as random.org (use list tool) to randomly pair students.

## Formative Assessment

Students create a list of things in their lives that are identified by unique numbers.

## Summative Assessment

1. End to End Architecture 6.1.1B
A. Describe the “end to end” architecture of the Internet.
B. Explain how the “end to end” architecture facilitates connection of new devices.

2. Internet Names and Address Rules 6.1.1 E
A. Describe how computers are uniquely identified and connected on the Internet.

3. DNS Function 6.1.1 G
A. Briefly explain the primary use of the Domain Name System made by users of the Internet.

4. DNS Hierarchy 6.2.1 B
A. Describe the hierarchy of the Domain Name System.

## Lesson Summary

Pre-lesson Preparation

This lesson will require some room setup or prep for best delivery of instruction. Some of the setup should have been done in the previous lesson.

Summary

In this lesson, students will expand their knowledge of how the Domain Name System (DNS) works by acting as a class to simulate the use of DNS to retrieve web pages.

Once the simulation is functioning students enhance its efficiency through the use of caching.

Poison the DNS cache by adding false DNS replies (DNS poisoning).

Students discuss with their groups how DNS works and how it supports Internet growth.

Then they explain in their journals how:

DNS works

Caching is both a benefit and a security risk.

DNS supports Internet growth.

In this lesson, students will expand their knowledge of how DNS works by acting out a simulation of DNS in action and using it to retrieve web pages. This is a two-session lesson. The first session is for students to get the simulation functioning, with the teacher serving as director.  As students realize they need to "fix" their implementation of the simulation (modify their scripts), they record the insights in their journals.

In Session Two, students take on different roles and conduct a dress rehearsal that is entirely student-led. Teachers then introduce DNS caching and DNS poisoning. Once the simulation is functioning, students will address both increased efficiency due to DNS caching, and cybersecurity concerns associated with DNS.

Outcomes

• Students will explore how the characteristics of the Internet influence the systems built on the Internet.
• Students will understand that Domain Name Servers (DNS) are essentially the "address book" of the Internet and store information to help Internet systems route requests and replies.
• Students will be able to explain how DNS hierarchy supports scaling on the Internet.
• Students will identify existing DNS cybersecurity concerns and potential options to address these issues.

Overview

Session 1 - Acting the Simulation

1. Lesson Introduction (5 min) - Students assign the cast and collect necessary data.
2. Guided Activity (40 min) - The teacher directs the first rehearsal of the play and introduces changes in IP and DNS.
3. Closing (5 min) - Think-Pair-Share

Session 2 - Round 2 of Simulations

1. Dress Rehearsal with Improvisation (15 min) - Practice Play
2. Rehearsal with Video (30 min) - Perform Play and Discuss DNS Caching and Poisoning
3. Closing (5 min) - Summary Report

## CSP Objectives

• EU DAT-2 - Programs can be used to process data, which allows users to discover information and create new knowledge.
• LO DAT-2.C: - Identify the challenges associated with processing data.
• EU AAP-3 - Programmers break down problems into smaller and more manageable pieces. By creating procedures and leveraging parameters, programmers generalize processes that can be reused. Procedures allow programmers to draw upon existing code that has already been tested, allowing them to write programs more quickly and with more confidence.
• LO AAP-3.F - For simulations: a. Explain how computers can be used to represent real-world phenomena or outcomes. b. Compare simulations with real-world contexts.
• EU CSN-1 - Computer systems and networks facilitate how data are transferred.
• LO CSN-1.B - Explain how the Internet works.
• LO CSN-1.C - Explain how data are sent through the Internet via packets.
• LO CSN-1.E - For fault-tolerant systems, like the Internet: a. Describe the benefits of fault tolerance. b. Explain how a given system is fault-tolerant. c. Identify vulnerabilities to failure in a system.
• EU IOC-2 - The use of computing innovations may involve risks to your personal safety and identity.
• LO IOC-2.C - Explain how unauthorized access to computing resources is gained.

## Math Common Core Practice:

• MP5: Use appropriate tools strategically.
• MP7: Look for and make use of structure.

## Common Core ELA:

• RST 12.3 - Precisely follow a complex multistep procedure
• RST 12.4 - Determine the meaning of symbols, key terms, and other domain-specific words and phrases
• WHST 12.6 - Use technology, including the Internet, to produce, publish, and update writing products
• WHST 12.7 - Conduct short as well as more sustained research projects to answer a question
• WHST 12.9 - Draw evidence from informational texts to support analysis, reflection, and research

## Key Concepts

The characteristics of the Internet influence the systems built on it.

Domain Name Servers are essentially the "address book" of the Internet and store information to help Internet systems route transmission requests and replies.

A list of character protocols is provided as a resource.  These may help students learn their roles.

## Essential Questions

• How are vastly different kinds of data, physical phenomena, and mathematical concepts represented on a computer?
• What is the Internet, how is it built, and how does it function?
• What aspects of the Internet’s design and development have helped it scale and flourish?

## Teacher Resources

Student computer usage for this lesson is: required

This lesson requires extensive preparation.

Acquire:

24 envelopes per class – one or two per host per rehearsal and production.

Post-it Notes

One color for students to use to self-select roles.

One color for students to use to record DNS information.

One color for students to use to initiate requests.

Print:

One copy of character protocols for each student.

One copy of Routing Table.docx for each student router.

One copy of DNS cache for each root, TLD, ANS and local DNS server and each host.

Four copies of each device/character role page (web, router,  root, TLD, ANS and local DNS and host).

Three or four copies of the first page web page, grouped by domain.

# Getting Started (5 min)

Warm Up:

Distribute post-it notes to each student.

• Students find their IP addresses and write their name and IP address on the post it note.
• Display the DNS device list on the board and use it to review the process by which DNS resolves domain names.

Casting Characters:

Beside each device listed on the board, there should be the number of students needed to play each role.  As soon as students complete their post it notes, have them choose their role by placing the post it notes next to the device name.

Below are suggested numbers of actors per role for two class sizes.  Students take their seats and add their name and IP address to their router table.

 Device List 16 Students 30 students Host 4 8 Local DNS 2 4 Root 1 1 Top Level Domain 2 3 Authoritative Name 4 6 Web Server 4 6 Router 1 2

Once students select a role, each device group should meet briefly to discuss what information they have to collect from the post-it notes on the board. They will go and obtain either a script that informs them what to do during the play, (how their device works) or all the printed web pages from their server.

Gathering Data:

Post this list of directions and allow devices to go to the board and obtain the required IP address information.

Before the play can start, these seven sets of data still have to be collected.

1. Web servers (students) need to "advertise" their web pages by making a list on the board of the web pages (one word per page) they have to offer.
2. Hosts and DNS servers complete a routing table for their table and give the routing table to their router.
3. Local DNS servers need to share their IP address with hosts.
4. Top-level domain servers need to share their domain names and IP addresses with the root server.
5. Authoritative name servers need to share their domain names and IP addresses with the top-level domain servers.
6. Web servers need to share their IP addresses with their authoritative name servers.
7. Routers need to complete the routing table for their group using the routing table (Routing Table.docx) provided.

# Guided Activity (40 min) - Guided Rehearsal

## Part 1 (30 min) - Rehearsal 1

Notes:

• During Round 1, the director can stop the action, provide direction, and restart the action.
• Actors should make notes in their journals of any stage directions, and make any changes or corrections to their scripts/role sheets as needed.

Steps to complete the play:

1. Select one Host to start. Hosts:
1. Select a web page to request.
2. To get the IP address of the web server, the HOST writes the domain of the page requested on a post it note, placing the request in an envelope, does not seal it, addresses the outside of the envelope (both from and to IP addresses), and sends the envelope via the Internet router.
2. Routers:
1. Verify the address are correctly formatted and forward the envelope using their routing tables.
2. Return envelopes not addressed properly – during dress rehearsal.
3. When the root server gets the request, it:
1. Opens the envelope.
3. Writes the IP address of the proper TLD server on the post-it note.
4. Uses the return address on the envelope to send it back to the local DNS server.
4. The local DNS server:
1. Opens the envelope.
2. Uses the IP address to readdress the question to the appropriate TLD.
5. The TLD server:
1. Repeats the process; writing the IP address of the proper ANS on the post it note.
2. Addresses the envelope back to the local DNS server.
6. The local DNS server:
1. Opens the envelope.
2. Uses the IP address to readdress the question to the appropriate ANS.
7. The ANS:
1. Writes the IP address of the desired web server on the post it note and circles it.
2. Sends the envelope back to the local DNS server.
8. The local DNS server:
1. Opens the envelope.
2. Upon finding a circled IP address, it sends the envelope back to the HOST.
9. The HOST:
1. Opens the envelope and replaces the post-it note with a request containing (only) the name of the web page desired.
10. The web server:
2. Opens it and replaces the post-it note with a printed version of the requested page.
3. Readdresses the envelope to the HOST.
4. Sends the page back.
11. Simulation completed! Celebrate when the requested web page arrives. Have everyone take a bow.

## Part 2 (10 min) - Changes in DNS

Explain:  Both domain names rules name and IP address rules have changed over time.

Have students watch these two videos:

Afterwards, they should record responses to these two prompts:

• How are naming rules changing and why?
• How are IP address numbers changing and why?

# Closing (5 min) - Think-Pair-Share

1. Before Round 2 (the dress rehearsal), have students make entries in their journals of any lessons learned. Have them share these lessons first with elbow partners, and then in groups.
2. Collect all scripts and web pages.
3. Present the DNS lesson summary project (DNS Summary).

# Dress Rehearsal with Improvisation (15 min)

Set the stage:

Distribute scripts, envelopes, and post-it notes.

• The rehearsal process repeats from the previous session; however, students are to select a different role and to work out on their own the simulation/improvisation.

Note: Use the character protocols from the previous session during the dress rehearsal, especially if the students are struggling.

• Select a host at random to start by requesting an available web page.  A little later, cue a second host.  If the system is working, cue a third host.  Go slower if needed.
• Return the web pages to the web servers. Before going live, give students a chance to ask any questions and to record any observations in their brain books.

# Rehearsal with Video (30 min)

## Part 1 (20 min) - Opening Night (If the show is ready)

This play is improvisational with Hosts requesting whichever pages they want.  Restart the system with all Hosts online.

1. Video the full DNS-based Web system in action.
2. Make a second video of the system acting slowly with only one Host.  In the second video, have students narrate their actions.
3. Introduce the use of DNS caching.
4. If time permits, add the use of DNS caching to the system. (Have students request a number of pages from the same domain, so pertinent cached values accumulate quickly.  If time is short, brainstorm benefits students anticipate for DNS caching.)
5. Have students record the benefits of DNS caching.

## Part 2 (10 min) - Attack

Introduce the security problems associated with plain text messages and with DNS poisoning:

Students will research this topic and report on security issues (among other aspects of DNS) in their summary report.

# Closing (5 min)

If the previous lesson has not been assessed, assign the entire summary in the document entitled "DNS Summary."

## Options for Differentiated Instruction

The simulation will be acted out at least three times.  Students should change to a new role each time.

Use the character protocols during the dress rehearsal.

## Formative Assessment

Students are to reopen their spreadsheets from the previous lesson.

Show the students how to create a simple "if statement" in a spreadsheet. The spreadsheet will become a tool where a user can type a domain name into a cell. If the respective IP address of that domain name is found, then that IP address is shown. If it is not then a "0" appears.

(See the sample spreadsheet in the Lesson Resources folder called "Sample Spreadsheet")

## Summative Assessment

A. Describe one rule change for names used on the Internet. Describe the rule before and after the change.

B. Describe one rule change for IP addresses used on the Internet. Describe the rule before and after the change.

C. Describe briefly the process by which the Domain Name System operates.

D. Briefly describe one way the Domain Name System was not designed to be completely secure.

E. Briefly describe one security concern and one coping strategy for the Domain Name System insecurity.

## Lesson Summary

Summary

This lesson investigates how the world wide web and search engines work.  Concepts of browsers and servers as well as he spiders that crawl the web in search of valuable information, the data farms that store the data, and the processes used to organize current and historical data. The search process starts before you ever type a query, by crawling and indexing trillions of documents. Students will create a concept map illustrating their understanding of the operations of a search engine. A concept map is an artifact that could be created as part of the Explore Performance Task at the end of Unit 3.

Outcomes

Students will be able to:

• Describe the processes used by modern search engines to index content on the Internet
• Arrange the order of operations used in creating an index.
• Define basic search engine terms: spider, bot, crawl, data farm,
• Compare category based searching with indexed searching.
• Use an online tool to create a knowledge diagram of related information.

Overview

1. Getting Started (5 min) - Think-Pair-Share on Internet Searches
2. Activities (40 min) - Students cultivate an understanding of searching and build concept maps.
3. Wrap-Up (5 min) - Share ideas

Source

The slides for the guided exploration of search methods were adapted from slides provided by Marie desJardins at the University of Maryland, Baltimore County.

## CSP Objectives

• EU CRD-2 - Developers create and innovate using an iterative design process that is user-focused, that incorporates implementation/feedback cycles, and that leaves ample room for experimentation and risk-taking.
• LO CRD-2.B - Explain how a program or code segment functions.
• LO CRD-2.C - Identify input(s) to a program.
• EU DAT-2 - Programs can be used to process data, which allows users to discover information and create new knowledge.
• LO DAT-2.B - Describe what information can be extracted from metadata.
• LO DAT-2.D - Extract information from data using a program.
• EU CSN-1 - Computer systems and networks facilitate how data are transferred.
• LO CSN-1.A - Explain how computing devices work together in a network.
• LO CSN-1.D - Describe the differences between the Internet and the World Wide Web.
• EU IOC-2 - The use of computing innovations may involve risks to your personal safety and identity.
• LO IOC-2.A - Describe the risks to privacy from collecting and storing personal data on a computer system.

## Math Common Core Practice:

• MP4: Model with mathematics.

## Key Concepts

Students will understand how the world wide web is structured and operates.

Students will understand the many processes that are required for an effective search engine.

Students will create diagrams and concept maps, do some investigations and discuss how search engines work, and then will individually use a computational tool to create an online diagram illustrating their understanding.

## Essential Questions

• How can computing extend traditional forms of human expression and experience?
• How are vastly different kinds of data, physical phenomena, and mathematical concepts represented on a computer?
• How can computation be employed to help people process data and information to gain insight and knowledge?
• How can computation be employed to facilitate exploration and discovery when working with data?
• What considerations and trade-offs arise in the computational manipulation of data?
• What opportunities do large data sets provide for solving problems and creating knowledge?
• How are algorithms implemented and executed on computers and computational devices?
• How are programs developed to help people, organizations or society solve problems?
• What is the Internet, how is it built, and how does it function?
• What aspects of the Internet’s design and development have helped it scale and flourish?
• How does computing enhance human communication, interaction, and cognition?
• What are some potential beneficial and harmful effects of computing?

## Teacher Resources

Student computer usage for this lesson is: required

# Getting Started (5 min)

Students should journal on the following question:

"How many searches do you think are done each day using the Google search engine?"

Pair and share, then show this amazing live counter of internet searches: http://www.internetlivestats.com/google-search-statistics/

## Activity 1 (25 min) - Understanding Search

Use the slide presentation "About Search Engines" (in Lesson Resources folder) to direct students through this lesson.

1. Students create a diagram of their best understanding of what happens when you type a query into a search engine. (Either provide the "Handout: You and the Search Engine Diagram" handout from the Lesson Resources folder or have students write on their own paper.)
2. Demonstrate how a search engine works with the video (first 2 minutes only) http://www.google.com/intl/en_us/insidesearch/howsearchworks/crawling-indexing.html  and diagram. Students can put a star next to each step in the process they thought of, then add to their diagrams to make them more complete.
3. Direct students to go to GoogleFight.com. [ for saving time just have the teacher demonstrate] Discuss what happens. Ask:
• Are all searches completed in the same amount of time?
• Why or why not?
• How does Google get the numbers to show on the results?
• Are the numbers really an indication of the popularity of one thing vs another?
4. Jigsaw into third’s and assign each third one of the following tasks.  Have students answer their assigned question based on the reading.

Read paragraphs 1 and 2 of Understanding Browser Tracking by Goodwill Community Foundation, Inc. What have you used online recently that is keeping a record – tacking – your usage?

Read paragraphs 1 and 2 of Locational Privacy – Issues by Electronic Privacy Information Center. What devices or systems are tracking your or your family’s location?

Read paragraphs 1 and 2 of HOW COMPANIES USE PERSONAL DATA AGAINST PEOPLE section 2.4 Key developments in recent years. How do companies individually identify us?

Share responses to each question with the class.

## Activity 2 (15 min) - Searching the Internet vs. Searching the Web

Describe at least three differences between the internet and the world wide web and identify which is searched by search enginges like Google or Bing.

## Homework - Optional Concept Map Creation

Have students create a concept map of ideas relating to search engines, doing additional research to round out their understanding. (See Teacher Resources for online tools that can be used to create concept maps.)

Share ideas from the students' concept maps. Point out that the concept map (if done online) is an artifact that was created using a computer to present information visually.

Optional Extension: (for fast moving classes who need more to do)

Google tracks everything that everyone queries. (Is this an invasion of your privacy?) The results are fascinating.

Look at www.google.com/trends. You can look at trends by region and limit them to a date and/or place. For example search for “Obama, McCain” limiting your search to 2008, and the United States. What conclusions do you draw?

Pick another topic of interest to explore in Google trends to reveal society’s interests.

## Options for Differentiated Instruction

Students can create diagrams and concept maps on paper by hand if that is helpful.

Be sure to assign roles to pairs when working together. Don't allow one partner to be passive while the other is active.

## Formative Assessment

Students create a concept map of what they learned with additional research on the topic.

## Summative Assessment

Students will develop a visual diagram of the processes involved in indexing the Internet by a search engine.

## Lesson Summary

Summary

This lesson has two main objectives.

The first focuses on search engine algorithms and the impact search engines have on our lives. Search engine page rank algorithms rely on many factors to predict what someone is looking for. The business advantage of appearing on the front page of a Google search is tremendous. However, as more information is tracked about our interests and preferences in order to customize the results of our searches, we have to ask whether or not the loss of privacy is worth the results.

The second objective is to introduce students to creating a visual artifact (knowledge required for performance tasks). Students will research a page ranking subtopic, prepare a one minute speech, and (if possible) create a video to accompany the speech.

Outcomes

• A presentation guides the discussion of how search engines work, what page rank is, and how results differ for a variety of reasons.
• Students will understand what metadata is, its relationship to data, and its uses.
• Students then do a quick research project to gather information on assigned, related topics
• Students create a 1-minute speech and presentation on their chosen research topic. If the classroom has the equipment, they will create a video artifact on their topic to share with the class either in the classroom or as homework posted online

### Overview

#### Session One

1. Getting Started (5 min) - Journaling on online search methodology
2. Activity (45 min) - Students discuss page rank and begin research for presentations

Session Two

1. Getting Started (5 min) - Journaling on search engine data mining and introduce presentation activity
2. Activity (35 min) - Create Presentations/Videos on previously researched topics.
3. Presentation of videos or talks (10 min)
4. Optional Homework: Have students watch the rest of the videos made and write about what they learned.

#### Session 3 New for 2020-2021

1. Getting Started (5 min) - Think-pair-share
2. Activity (35 min) - Metadata exploration
3. Wrap Up  (5 min) - Metadata and Privacy

## CSP Objectives

• EU DAT-2 - Programs can be used to process data, which allows users to discover information and create new knowledge.
• LO DAT-2.A - Describe what information can be extracted from data.
• LO DAT-2.B - Describe what information can be extracted from metadata.
• LO DAT-2.C: - Identify the challenges associated with processing data.
• LO DAT-2.D - Extract information from data using a program.
• LO DAT-2.E - Explain how programs can be used to gain insight and knowledge from data.
• EU AAP-2 - The way statements are sequenced and combined in a program determines the computed result. Programs incorporate iteration and selection constructs to represent repetition and make decisions to handle varied input values.
• LO AAP-2.A - Express an algorithm that uses sequencing without using a programming language.
• EU IOC-1 - While computing innovations are typically designed to achieve a specific purpose, they may have unintended consequences.
• LO IOC-1.B - Explain how a computing innovation can have an impact beyond its intended purpose.
• LO IOC-1.F - Explain how the use of computing can raise legal and ethical concerns.
• EU IOC-2 - The use of computing innovations may involve risks to your personal safety and identity.
• LO IOC-2.A - Describe the risks to privacy from collecting and storing personal data on a computer system.

## Key Concepts

Students will understand that the page rank algorithm depends on many factors, has changed over time, and has a large impact on the traffic that a site gets.

Students will give examples of how their activity online is tracked and how the knowledge of them is used to taylor the results and the possible repercussions.

Students will create an artifact using screen capture of themselves discussing and analyzing an aspect of searching.

## Essential Questions

• How can computing extend traditional forms of human expression and experience?
• How can computation be employed to help people process data and information to gain insight and knowledge?
• What is the Internet, how is it built, and how does it function?

How can computing extend traditional forms of human expression and enhance people’s ability to find information and solutions?

## Teacher Resources

Student computer usage for this lesson is: required

### In the Lesson Resources folder:

• "Search Engine Background" NOTE: This document explains the content of each slide in the presentation WITH answers to the questions in the presentation.
• "PageRank" - slide presentation
• Handouts for students (can be placed on the student's drives or printed out on paper):
• "PageRank Student Handout" (optional notes to go along with the PowerPoint - gives students a place to answer questions posed in the presentation)
• "1 minute talk directions.odt" (to help students organize their video)
• "Sample 1 minute script on keyword matching"
• "Sample 1 minute video artifact on keywords.swf" (1:15)

# Getting Started (5 min)

Students should take a few minutes to journal on the following question:

Which are you more likely to do if you don't see an answer to a search request on the first page: click forward to page 2 of the results or ask the question differently? Why?

(Encourage students to discover that it is very valuable to business to appear at the top of the search engine rankings and that often thousands or millions of results are returned in a single search.)

# Activity (45 min)

## Part 1 (25 min) - How Search Engines Work

(Use the PageRank presentation in the lesson folder to guide the discussion.)

Note: Guidelines for the teacher are in the "Teacher Notes on PageRank Presentation" document. This document also contains an answer key.  (Students can record their notes in the "PageRank Student Handout".)

1. Watch the three-minute video on Google search closely to pick up details. Pause, take notes, and discuss as needed.
2. Emphasize that results are found in the database, and then information filtering systems, which take large data sets and eliminate data that is not of interest, help find the most relevant information and identify patterns in the information to better organize it.
3. Allow students to generate ideas on why one webpage might have a higher PageRank than the other. [slide 3]
4. Look at the HTML code of the webpage in the PowerPoint to discover the frequency of keywords including synonyms, and occurrence in titles and metatags. [slide 4] (Student handout also has a printout of the HTML code for students to get a closer look.)

What concerns does the Navy have about the information posted online?

Do these same concerns apply to people not in the military?

6. Discuss possible reasons why two different people can get different results doing the same search.
7. Read the first three sections Internet is forever, except when it is not from Ask Leo.com.

How hard is it to permanently delete information once it is posted on the internet?

What advice would you give to a young person about posting their information online?

## Part 2 (20 min) Preliminary Research for creation of video artifacts/PowerPoints

1. Assign topics for research to student groups. (There are additional topics in the "Search Engine Background" information document if desired). Here are several suggestions:
• What are additional factors in page rank?
• What do people do to achieve SEO? (search engine optimization)
• What is Google bombing? How does it work?
• How much storage is needed to store Google’s index? How many server farms are needed to store it all? What is the design philosophy of server farms?
• What’s the environmental impact of server farms? How do they try to stay green?
• How does advertising affect search engines? Is it necessary? What is “pay per click” and “click fraud”?
• How is Google getting good at finding things like pictures, videos and other kinds of information beyond just words?
• How do directories work? Show some examples, such as https://dir.yahoo.com/ .
2. If you have video recording equipment: Demonstrate how to create a high-quality video artifact (the kind students might choose to create for their Performance Task).
• Student handout: 1 minute talk directions -- go over this handout with them.
• Show the Sample 1 minute video artifact on keyword matching (in the Lesson Resources folder).
3. With the remaining time, have students begin their research on their chosen topic.

# Getting Started (5 minutes)

## Journal (3 min)

Why could it be beneficial for a search engine to keep track of what people are searching for? In what ways do computers enhance our ability to solve problems? Discuss.

(Possible answer to lead students toward: Topics sporadically become popular, and knowing what results people like can make it easy to suggest sites to others looking for similar things. History data can also enable a search engine to suggest a search phrase when a single word or only a few letters are typed in. The better a search engine knows what you are looking for, the better it can filter results to include results relevant to your query.)

## Introduction (2 min)

Explain that students will be creating a presentation on the topic they researched in the last session. This presentation should be scripted, and make use of a PowerPoint and sources from the internet. They will have 30 minutes to make this presentation. (Slide 8 is made for video creation, but works well for general presentations too.)

For classes with enough video recording equipment for all groups:

Explain that students will create their own video explanations of how one feature of search engines works. Go over the "1 minute talk directions.odt" together to help students organize their video. The creative design process to develop such a short, focused product requires good teamwork, organization, and creativity. Plan out what the key message is, what visuals will add the most value, and then craft the wording to fit within the 1 minute time frame.

# Activity (35 minutes)

Students should split into their groups and begin work. Allow only 10 minutes for additional research as needed. They will take the remaining 25 minutes to:

1. Make a PowerPoint, gather search results to use as examples, create a rough script, and practice their presentation.
2. If they are making a video: Write a script, either create a PowerPoint to voiceover or choose some search results to analyze, and practice. The last 5-10 minutes should be used to record a 1 minute video clip of their presentation allowing for multiple retakes)

# Presentation of videos or talks (10 minutes)

Show as many videos/ group presentations as you can share with the class. If there are videos, assign the remainder to be watched as homework and have students bring in notes on the key points learned from each video.

Session 3 New for 2020-2021

Getting Started

Warmup:

1 What can we conclude from the following two statements?

• Computers store web pages.
• Everything stored in a computer is stored in bits.

2 How do you think the computer can tell which bits are for the title of a page and should be large and which bits represent plain text on the page and should be smaller?

## Introduction

Say: According to the  Dublin Core Metadata Initiative Metadata Basics page (), metadata is "data about data" -- specifically, descriptive metadata -- is structured data about anything that can be named, such as Web pages, books, journal articles, images, songs, products, processes, people (and their activities), research data, concepts, and services. Creative Commons Attribution 3.0 Unported License

In this session, we will investigate what metadata is, its relationship to data, and its uses.

## Activity

### Part 1

Watch the first 40 seconds of this video to complete these two sentences.

Metadata are pieces of information that make studies ______________ & ______________.

Metadata helps you make_________ of the ___________.

https://youtu.be/-4_MFhi4GpU

Watch the first 90 seconds of this video. After watching the Meta... What? Metadata! video, define metadata in your own words.

• What is it used for?
• What are the consequences of changing it?

.

Colin Hines www.ColinHinesPhotography.com [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0/)]

Think-pair-share: Discuss with your elbow partner

• What is it used for?
• What are the consequences of changing it?

### Part 2

Say:  If metadata tells us what data means - what information it contains - then what tells us what metadata means.?

Consider the XML for these messages.

<messages>

<note id="23">

<to>Marcus</to>

<from>Lin</from>

<body>Don't forget our appointment!</body>

</note>

<note id="24">

<to>Lin</to>

<from>Marcus</from>

<body>What meeting</body>

</note>

</messages>

Ask: How does the metadata make using the data itself more effective?

The metadata tells us what the data (in black) means.  To find out what XML, means we need to consult a standard.  Examine the standards recommended by the W3C for XML.

Say:  On a web page the data is what people need to see.  The metadata is what computer systems use to present the data in useful ways.  One large computer system is the internet. Every message/file transmitted on the internet is first broken into small fragments and each fragment packed in packets. These packets contain a lot of metadata that make delivery of the packets by the routers (computers) of the internet both possible and reliable.

### Part 3

Visit the IP packet structure web page and examine the metadata that is part of every packet transmitted on the internet and answer these questions.

• What two addresses are part of the metadata in every packet?
• What part of the metadata is used to put the fragments back in the order they were before the message/file was broken into fragments?

## Wrap up:

Watch this video from International Privacy.org then discuss these two questions with your elbow partner.

• What would happen if metadata was banned successfully?

## Options for Differentiated Instruction

For a shorter class, don't have students take notes, just discuss the slides.

For the Explore performance task, each student should be able to create their own artifact. You could have the students work on the presentations individually in this lesson, as a practice for the Explore task, if your class is fairly competent with the technology.  For students with less experience (or to save time during presentations), it could be beneficial to have students create these artifacts in pairs, with some pairs repeating topics for comparison.

## Formative Assessment

Students share best definitions of page rank related terms

Students analyze web pages for reasons for differences in page rank

## Summative Assessment

Students create a one-minute video clip on a topic related to the operation of search engines.

## Lesson Summary

Summary: This lesson is designed for students to review basic statistics, including calculations of the mean, median, mode, and standard deviation. It will also give the students some experience using spreadsheet software to calculate the statistics and to create histograms.  Note: This lesson is intended primarily as a review and a reminder of material that should already be familiar to the students. If your students have little familiarity or experience with using Excel to compute statistics or generate plots, you may wish to extend this lesson to two sessions, and provide more scaffolding and instruction on the basic mechanisms.

Outcomes:

• Students will review the basic statistical concepts of mean, median, mode, and standard deviation.
• Students will use spreadsheet software to calculate the statistics and to create histograms.

Overview:

1. Getting Started (5 min)
2. Introduction of Content (10 min) - Statistics Introduction and Review
3. Guided Activity (30 min) - Students Create Plots and Calculate Candy Statistics
4. Wrap Up (5 min) - Journal

Source: This lesson was adapted from Unit 2: The Engineering Design Process, Lesson 2: Collecting and Processing Information ©2013 International Technology and Engineering Educators Association Foundations of Technology, Third Edition/ Technology, Engineering, and Design

## CSP Objectives

• EU DAT-2 - Programs can be used to process data, which allows users to discover information and create new knowledge.
• LO DAT-2.D - Extract information from data using a program.
• LO DAT-2.E - Explain how programs can be used to gain insight and knowledge from data.

## Math Common Core Practice:

• MP5: Use appropriate tools strategically.

## Common Core Math:

• S-ID.1-4: Summarize, represent, and interpret data on a single count or measurement variable

## Common Core ELA:

• RST 12.10 - Read and comprehend science/technical texts

## NGSS Practices:

• 5. Using mathematics and computational thinking

## Key Concepts

The students must understand the basic statistical concepts of mean, median, mode, and standard deviation. They must also be able to use spreadsheet software to calculate the statistics and to create histograms.

Students often have some initial difficulty learning how to use formulas in the spreadsheet software to do the calculations.

## Essential Questions

• How can computation be employed to help people process data and information to gain insight and knowledge?
• How can computation be employed to facilitate exploration and discovery when working with data?

## Teacher Resources

Student computer usage for this lesson is: required

For Each Student:

• Package of colored candy. Alternatively, you can ask students at the end of the previous lesson to collect some distributional data to use for the exercise (ideas: colors of cars in the school parking lot, colors of shirts worn by students in the room, favorite sports teams or bands of the students), or you can simply provide some data for the students to use. This could be either representing colors of candy (using the test data in the lesson if you would like), or similar distributional statistics.
• Excel software or other spreadsheet software
• Web resource with information about measures of central tendency: https://statistics.laerd.com/statistical-guides/measures-central-tendency-mean-mode-median.php

# Getting Started (5 min)

• Students should describe what they know about statistics in their journals.
• Have students share what they know about statistics and introduce the lesson.

# Introduction of Content (10 min)

Review of Statistics:

Present a review of basic statistics (min, max, mean, median, mode, and range), and use the following board exercise to have the class review their understanding of these basic concepts:

• Ask eight or so randomly selected students for their birth date (day of the month).
• Write these numbers on the board.
• On the side of the board, list the key terms "min," "max," "mean," "median," "mode," and "range."
• Ask the class as a group to compute each of these values:
• Min: The smallest number (what if there is more than one? - no problem!)
• Max: The largest number (what if there is more than one? - no problem!)
• Mean: The average (sum of the numbers, divided by how many numbers there are)
• Median: The center value in a sorted list of numbers.
1. Have the students help you to rewrite the values from smallest to largest.
2. Which is the middle number?
3. Since there are 8 numbers, there is no middle number!
4. In this case, the median is the mean (average) of the two center numbers = 4th number + 5th number / 2.
• Range: The difference between the largest and smallest value (max - min).
• Mode: The most frequently appearing value.  In such a small set, there is likely to not be a mode, unless two students happen to share the same birth date.  You might wish to poll the students for another number (e.g., the students' grade) that's likely to have more repeated values, and then compute the mode (and, optionally, the other statistics).

Discussion:

Ask the class to come up with situations where it might be most useful to compute the mean, median, or mode of a set of values.  Encourage them to understand that each of these statistics can be useful in different situations, but may be misleading.  Have them generate sets of data that would give "misleading values" for mean (if there is an "outlier value"), median (if the values have a longer "tail" on one side than the other), or mode (if there is a frequent value that happens to occur at one end or the other of a wider range).

# Guided Activity (30 min) - Candy Statistics

Note: The teacher may want to do this activity along with the students, displaying the spreadsheet on a screen so that the students may ask questions and see how to do the statistical calculations using the spreadsheet software. Students who do not have much experience with spreadsheets may need more scaffolding and instruction. (If you have many such students, you may wish to spread this lesson out over two class sessions.)

Students will use spreadsheet software, such as Excel, to calculate the average number and standard deviation of candy color in an individual-sized bag of M&Ms, Skittles, or other colored candy. Optionally, students may compare their results to other online published statistics for each candy.

1. Have the students predict how many individual candy pieces are in their bag of candy and write their predictions in their journals.
2. Have the students open their bag of candy and sort the candy into categories based on color.
3. Have the students note the difference in the total number of candies predicted versus the actual number that was in the packet. They should note the difference in their journals.
4. Open an Excel program and create a spreadsheet like the following. Each Trial Number in the example below corresponds to a student or group in the class.  (Note: If you do not have candy to do the counting exercise, you may simply give the sample spreadsheet below to the students.)
 Candy Statistics Trial Number 1 2 3 4 5 6 Yellow 17 20 24 19 19 17 Red 21 13 19 21 15 18 Blue 10 18 16 18 21 20 Brown 7 12 5 12 12 14 Green 26 26 16 17 22 18 Orange 24 16 20 15 15 16 Package Total 105 105 100 102 104 103

The students will also need to create columns further to the right labeled Mean, Median, Mode, and Standard Deviation.

 Mean Median Mode Standard Deviation 19.375 19 19 2.199837656 18.125 19 19 2.799872446 17 17.5 18 3.338091842 9.5 10 12 3.380617019 21.125 22 22 3.833592124 18.25 17.5 16 3.284161124

1. Each student will enter their own data for each color and the data from another student or group into the table.
2. Using their data, students will:
1. Calculate the mean value for each color category within the experiment. They should use the Average function to do the calculation.
2. Calculate the median, mode, and standard deviation for all color categories. They should use the appropriate functions to do the calculations.
3. Calculate the package total for each trial by using the `SUM` function.
4. Create a ± 3ϭ histogram for each candy color.
5. Create a frequency distribution table for each candy color, as illustrated below.
6. Create a histogram for each candy color, using your bin and frequency data.
 Yellow Candy σ = 2.19984 Get on 3Cs 25.9745 2S 23.7747 1s 21.5748 Mean 19.375 -1s 17.1752 -2s 14.9753 -3s 12.7755

# Wrap Up (5 min)

Students will answer the following question in their journals:

• Why is it important to use statistics to understand large data sets? When are different measures of central tendency appropriate or inappropriate?

## Options for Differentiated Instruction

Learners may be paired to assist each other in the use of the spreadsheet software.

## Formative Assessment

The teacher should frequently check the students' work for accuracy as the lesson progresses so that misunderstandings may be quickly resolved.

## Summative Assessment

• Have the students calculate the mean, median, mode and standard deviation of a set of data.
• Have the students use a spreadsheet to do statistical calculations and create a histogram.

## Lesson Summary

Summary

This lesson provides the students with an opportunity to practice the AP CSP Explore Performance Task with a given set of tasks from which they may choose. Students will use a rubric to perform self-assessment of work generated for the Explore Performance Task.

Outcomes

• Students will practice the AP CSP Explore Performance Task.
• Students will use a rubric to grade the paper created in the previous class to evaluate their own work and make modifications where necessary.

Overview

Session 1

1. Getting Started (5 min)
2. Introduction of Content (10 min) Introduce the practice Explore Task and review the rubric.
3. Independent Activity (30 min) Write responses to questions posed on "Practice Explore Task Response Document" research and summarize results with a focus on using few words to convey a significant message.
4. Wrap Up (5 min)

Session 2

1. Getting Started (5 min)
2. Independent Activity (40 min) Work on artifacts (original digital artifact screencast or a knowledge map diagram) to express the effects of your chosen innovation.
3. Wrap Up (5 min)

Session 3

1. Getting Started (5 min)
2. Independent Activity (40 min) Collect written responses, continue to work on artifacts. Share exemplary features with the class as time allows.
3. Wrap Up (5 min)

Source: The lesson models the College Board AP CSP Explore Performance Task.

## Common Core ELA:

• RST 12.1 - Cite specific textual evidence to support analysis of science and technical texts, attending to important distinctions the author makes and to any gaps or inconsistencies in the account.
• RST 12.6 - Analyze the author's purpose in providing an explanation, describing a procedure
• WHST 12.1 - Write arguments on discipline specific content
• WHST 12.2 - Write informative/explanatory texts, including the narration of historical events, scientific procedures/experiments, or technical processes
• WHST 12.9 - Draw evidence from informational texts to support analysis, reflection, and research

## NGSS Practices:

• 7. Engaging in argument from evidence

## NGSS Content:

• HS-ETS1-3. Evaluate a solution to a complex real-world problem based on prioritized criteria and trade-offs that account for a range of constraints, including cost, safety, reliability, and aesthetics as well as possible social, cultural, and environmental impacts.

## Key Concepts

The students will be able to use reliable research findings to generate a computational artifact and respond to questions on that innovation.

## Essential Questions

• How can a creative development process affect the creation of computational artifacts?
• How can computing and the use of computational tools foster creative expression?
• How are vastly different kinds of data, physical phenomena, and mathematical concepts represented on a computer?
• How can computation be employed to help people process data and information to gain insight and knowledge?
• What considerations and trade-offs arise in the computational manipulation of data?
• What aspects of the Internet’s design and development have helped it scale and flourish?
• How does computing enhance human communication, interaction, and cognition?
• How does computing enable innovation?
• What are some potential beneficial and harmful effects of computing?
• How do economic, social, and cultural contexts influence innovation and the use of computing?

## Teacher Resources

Student computer usage for this lesson is: required

In the Lesson Resources folder:

• "Explore_Performance_Task_Rubric_Nov2015" : AP test rubric for the overall practice performance
• "Practice Explore Task Job Completion Check List" : check list for task jobs
• "Practice Explore Task Response Document November2015" : response document
• "CSMattersWritingRubric.docx" : detailed formative assessment writing-specific rubric for the practice Explore performance task

# Getting Started (5 min)

• Previous evening's homework was to complete the Practice Explore Performance Task worksheet.
• Group students by topic in groups of 3 – 4.  Have students share findings with each other and report any missing items.  Teacher will need to circulate to assist where needed.

# Introduction of Content (10 min)

Instruct the students that they are to use their findings to generate a computational artifact and a one-page paper on an innovation.

## Directions for artifact:

The artifact is an original digital artifact screencast or knowledge map diagram that you create to express the effects of your chosen innovation.

## Directions for the Paper:

Students are to generate a written document in which they respond directly to the following prompts.  Their document should be a one-page paper that may include illustrations.

• Describe the area of our lives (social, economic, or cultural) that has been most impacted by the innovation, and discuss the significance of the innovation to this area, using references to support your argument.
• Describe the population that is affected by the innovation and explain why that population is significant.
• Describe the connection between your artifact and the innovation you explored.
• Identify and describe how information sharing has affected this innovation.
• Discuss the extent to which this innovation is dependent on the Internet.
• Describe any security concerns and explain how they relate to the innovation.
• Describe the beneficial as well as any harmful effects of the innovation you explored.

# Independent Activity (30 min)

Writing responses to questions posed on "Practice Explore Task Response Document" and creating artifact.

Remind students that brevity is important for the performance tasks; it is a talent to be able to get a message across with real content succinctly.

I have made this letter longer than usual, only because I have not had time to make it shorter. ~Blaise Pascal (1623-1662).

# Wrap Up (5 min)

Have students complete the "Practice Explore Task Job Completion" form, indicating where they are in the process of the Practice Artifact.

## Homework

Complete any additional research needed to complete the document (if needed).

# Getting Started (5 min)

The previous evening's homework was to complete the paper that students were working on in the previous class.  Pass out the rubric and have students go through their paper to verify that they have all points covered.  Point out that most of the points awarded are based on the report (75% of the total score) and the artifact represents 25% of the score.  Teacher will need to circulate to assist where needed.

# Independent Activity (40 min)

• Students are to make any modifications necessary on their paper and work on the artifact.  The entire project will be collected next class.
• The artifact is an original digital artifact screencast or a knowledge map diagram that you create to express the effects of your chosen innovation.

# Wrap Up (5 min)

Have students complete a Job Progress form indicating where they are in the process of the Practice Artifact.

## Homework

Complete the paper using the rubric as a guide.  Complete the plan for the artifact; you will have one more class period to work on the artifact before the project is due.

# Getting Started (5 min)

The previous evening's homework was to complete responses to "Practice Explore Task Response Document" modifications as indicated using the rubric that students received in the previous class.  Using the artifact part of the rubric, have students go through their plans for the artifact to verify that they have all points covered.  Point out that most of the points awarded are based on the report (75% of the total score) and the artifact represents 25% of the score.  Teacher will need to circulate to assist where needed.

# Independent Activity (40 min)

The responses to "Practice Explore Task Response Document" for the Practice Explore Performance Task should be complete.  Students should be focused on the artifact.  The entire project will be collected next class.

# Wrap Up (5 min)

Have students complete a Job Progress form indicating where they are in the process of the Practice Artifact.

## Homework

Complete artifact using the rubric as a guide.  The Practice Explore Performance Task is due at the start of the next period.

## Options for Differentiated Instruction

SPED/LLD:  need to be frequently monitored and assisted as needed.

Teachers may choose to spread this activity out into multiple class sessions over a longer period of time, to give students some more time to work on the paper and artifacts at home (especially if the class meets every day, since "overnight homework" is often difficult for students to complete effectively when they are involved in other after-school activities and have assignments for other classes).

## Formative Assessment

Practice Explore Performance Task -- provide feedback, using College Board's rubric (Explore_Performance_Task_Rubric_Nov2015.pdf and the CSM detailed Explore Task writing rubric (CSMattersWritingRubric.docx and CSMattersWritingRubric.pdf) -- both can be found in the lesson folder

## Lesson Summary

This is the second of three lessons where students will research a computing innovation.

This lesson will focus on:

Identify data privacy, security, or storage concern

# Session 1

## Introduction

Say: In this lesson, we are going to work individually to investigate a computing innovation.  All computing innovations use data and to some degree expose the data to risk.  In this lesson, you will identify a computing innovation and describe a privacy, storage or cybersecurity concern.

All computing innovations have a purpose, a purpose that guided the developers in its production.  Some privacy, data security or data storage concerns about the innovations may have been known by the developers.  Others may have become known only after the innovation was in use.

With elbow partners, list five or so kinds of information that most people want to remain private.  Create a class list of these a list of these.

## Activity 1

Say.  Some personally identifiable information is protected by law is PII. Have students visit this website for a definition of PII. (https://github.com/ca-cwds/Information-Security/wiki/Definition-of-PII-(Personally-Identifiable-Information))

Provide the list below and ask students to identify what elements in our list are also listed as proteced by law.

Personally identifiable information (PII) is information about an individual that identifies, links, relates, or describes them. Examples of PII include:

• social security number
• age
• race
• phone number(s)
• medical information
• financial information
• biometric data

## Activity 2

Select one of the three concerns from activity 1 to focus upon.

Research and prepare a report assessing the risk and providing guidance on how to protect against that risk.  The report must include citations of at least two references assessing the concern and two reference for protecting against the risk.

# Session 2

## Activity 1

Prepare a one minute report about the concern you wrote about in the last sessions.

## Activity 2

Computing Innovation data concern presentations.

## Lesson Summary

Pre-lesson Preparation

Assigning some of the research as homework will allow more in-depth research.

Summary

Reflecting on the fact that the Internet was not designed with security in mind, students will examine the devastating impact of cyber attacks. Students will study types of cyber attacks and the vulnerabilities they exploit and identify the roles of software, hardware, people, and the Internet. Students will identify potential cybersecurity concerns in systems built on the Internet.

## CSP Objectives

• EU CRD-1 - Incorporating multiple perspectives through collaboration improves computing innovations as they are developed.
• LO CRD-1.C - Demonstrate effective interpersonal skills during collaboration.
• EU IOC-2 - The use of computing innovations may involve risks to your personal safety and identity.
• LO IOC-2.B - Explain how computing resources can be protected and can be misused.
• LO IOC-2.C - Explain how unauthorized access to computing resources is gained.

## Common Core Math:

• S-IC.1-2: Understand and evaluate random processes underlying statistical experiments

## Common Core ELA:

• RST 12.4 - Determine the meaning of symbols, key terms, and other domain-specific words and phrases
• RST 12.9 - Synthesize information from a range of sources
• RST 12.10 - Read and comprehend science/technical texts
• WHST 12.1 - Write arguments on discipline specific content

## Key Concepts

6.3 Cybersecurity is an important concern for the Internet and the systems built on it.

The Internet was not built with security in mind, leaving computers vulnerable to cyber attacks. This makes cybersecurity an extremely important concern when designing and implementing systems that are built on the Internet. Students need to be able to identify potential problems that could arise and potential options for protecting against these problems.

## Essential Questions

• How is cybersecurity impacting the ever increasing number of Internet users?
• How does computing enable innovation?
• What are some potential beneficial and harmful effects of computing?
• How do economic, social, and cultural contexts influence innovation and the use of computing?

Outcomes

• Students will understand types of security violations.
• Students will understand types of protections.
• Students will compare negative impacts of different types of attacks.

## Teacher Resources

Student computer usage for this lesson is: optional

In the Lesson Resources folder:

• "Cyber Security" : slides for instruction during the whole class
• "Cyber Attacks News Articles" : the list of news articles about real life cyber attacks for teachers (with instructions)
• The diagram for the sticky note activity is in this document
• "Cyber Attacks Notes WS" : worksheet for students to use in taking notes on different types of attacks
• Consider including the TED talk about the first virus (about 17 minutes long) by Mikko Hyponnen https://www.ted.com/talks/mikko_hypponen_fighting_viruses_defending_the_net

Journal Sample Response:

• "The Internet was originally designed to be used by a group of people who trusted each other. This means that it was not built with security in mind, but rather openness and sharing. Now that anybody can access the Internet, users cannot trust everybody else they are connected to. This means that security measures must be put in place to protect users and systems."

Example for Presentations:

Information to present about firewalls. (Included in the slides)

“You can protect against certain attacks. One way to protect against them is a firewall.”

1. Where did the name come from?
1. We have physical firewalls in school (and other buildings) that are designed to open to let people in and out, but close to keep fire contained (don’t let it through)
2. How does it work? Describe the process, making sure to note the role of each of the following: (not all will necessarily apply)
1. A firewall is installed to be a barrier between a computer (or local network) and the Internet. A person has to purchase / install the firewall to protect their system. Firewalls can be software or hardware and sometimes people use both. Firewalls examine the packets attempting to go in or out from the computer (or local network) to/from the Internet. It can keep attacks like viruses out, and keep sensitive or private data in.
3. Visual from https://mdilog.com/help/security

## Lesson Plan

(Note: There is a PowerPoint to be used with this entire lesson: "Cyber Security Lesson Slides" in the Lesson Resources folder.)

# Getting Started (5 min)

In their journals or as a class, students should discuss the following:

1. Describe the “trust model” that the Internet was originally designed upon.
• The "trust model" was introduced in Lessons 3-4, 3-5, and 3-6 that introduced the Internet.
2. List the problems with using the trust model, now that anybody can access the Internet.
3. Define cyber crime and cyber warfare. How are they different from everyday crime and warfare?
(cyber crime: https://us.norton.com/cybercrime-definition ; cyber warfare: http://time.com/3928086/these-5-facts-explain-the-threat-of-cyber-warfare/ )

# Guided Activities (40 min)

## Part 1 (10 min) - Readings

1. Each student will read a short article from the news about a specific attack that took place and identify the type of attack. Through their readings, the students will identify the negative effects of the attack. (A list of possible articles is in the "Cyber Attacks News Articles" document in the lesson folder.)
2. Students will use sticky notes to record the following information (at least one per student):
1. The student's name
2. The type of cyber attack
3. The impact of the cyber attack
3. On the board, the teacher will set up space with the types of attacks on the y-axis, and the level of impact on the x-axis (see teacher resources). Students will place the sticky notes on the diagram where they think it fits.

## Part 2

2a. Say: What can be done to protect our online security and privacy?  Institutions can implement Multifactor and 2-factor authentication.
Show the videos:  Multifactor and 2-factor authentication
Discuss: multifactor identification.  Be sure all four points below are discussed. (Suggestion, play it like Family Feud, keep getting ideas until all key points below have been revealed and add other ideas as they are suggested)

1. Authentication measures protect devices and information from unauthorized access. Examples of authentication measures include strong passwords and multifactor authentication.
2. Multifactor authentication is a method of computer access control in which a user is only granted access after successfully presenting several separate pieces of evidence to an authentication mechanism, typically in at least two of the following categories: knowledge (something they know); possession (something they have), and inherence (something they are).
3. Multifactor authentication requires at least two steps to unlock protected information; each step adds a new layer of security that must be broken to gain unauthorized access.

2b. Say:  What can we as users do?
Discuss with students what they think they can do.  Be sure all six points below about what users can do are discussed.

1. Use strong and unique passwords for internet sites.
2. Control permissions granted to software to collect information and regularly review permissions granted to the software.
3. Avoid the installation of software from unknown or unreliable sources.
4. Keep antivirus and antimalware software up to date and active.
5. Keep operating system and application patches up to date.
6. Use a VPN whenever connected to a public wireless network.

## Part 3

### Group Projects

Individuals can manage passwords, network and credit card use.

3. Use a password unique to each site.
4. When using a public network, use a VPN
5. Pay with Smartphones or smart cards
6. Use software data collection/privacy settings

Organize the class into seven groups and assign a topic above to each.  Ask students to think about what the technology is, why it is important and how it is used.

Allow students five minutes to research the topics. Allow 5 minutes to prepare a poster about each.  Present and answer questions about each.

## Part 4

### Survey of threats

4a. Say:  All real-world systems have errors or weaknesses that make the susceptible to attack.  One approach to making them safe is to detect and prevent these attacks.  We are going to investigate malware and virus attacks. Show the video Malware: Difference Between Computer Viruses, Worms and Trojans. Have a brief class discussion on computer viruses using the questions below as prompts.

• How is a computer virus like a human virus?
• Do free antivirus programs work?
• How much do commercial antivirus programs cost?

4b. Say:  Attacks come from unknown senders, or spoofed or compromised known senders. Show the What is Phishing video. Have a brief class discussion on phishing using the questions below as prompts.

• What type of bait might attackers use to trick high school students?
• How should you handle a suspect email?

4c. Say: Some attacks take advantage of keyloggers.  Show the Cyber Security Minute: Keyloggers video. Have a brief class discussion on keyloggers using the questions below as prompts.

• What do keyloggers do?
• What sort of information might they be used to obtain?
• How can you protect yourself from keyloggers?

4d. Ask:  Why is the danger of free downloads is a special risk to young people? Visit the site 7 Quick Sites That Let You Check If a Link Is Safe and identify two tools you could use to identify safe downloads.

4e. Ask: What is an access point to a network? (Ans: a point of connection that can communicate with the network)

Say: According to Wikipedia, A rogue access point is a wireless access point that has been installed on a secure network without explicit authorization from a local network administrator.  Rogue access points can give access to the network with authorization and can be used to intercept or modify network traffic that is traveling through it.

Solicit at least 3 examples of how this could be a problem on a secure network.

4f. Ask: What does it mean if something is malicious? (Ans: it has bad intentions)
Say: According to ZDnet,"85% of all malspam sent in Q2 2019 (April, May, and June) contained a link to a malicious file download, rather than the actual malicious file attached to the email." Have a brief class discussion on malicious email using the questions below as prompts.

• What makes a link malicious?
• Why do you think attackers may be using malicious links instead of email attachments?
• Do you think there are malicious links on web pages? (yes, for sure!)

4g. Say:  In addition to attachments and malicious links - whether in an email, message or on a web page, email from an unknown sender or a known sender whose computer has been compromised may contain active contents such as forms or videos that can be used to compromise your computer security, your privacy or both.  Discuss with students ways malicious software can be installed on their computers.  Be sure to address the points below.

• Active content in email or messages
• Malicious content isn't always from unknown sources, it can come from a known website (it could be hacked) or sender (their email could be spoofed, or they might unknowingly be sending something bad or have been hacked)

Optional programming activity.

Visit the PyPi website  keylogger 2.7.3 and read the Use cases.

• What are three legitimate uses for a key logger?
• What are three illegitimate uses for a key logger?

Optional research activity.

Students will be grouped by the type of attack they read about. They will conduct research to answer the following questions: (some resources will be provided, but students can also search for others. If no computers are provided, it will be up to the teacher to find these additional resources)

1. Where did the name come from?
2. How does the attack work? Describe the process, making sure to note the role of each of the following: (not all will necessarily apply)
1. The Internet
2. Software
3. Hardware
4. People
3. Find or create a visual that illustrates the attack OR act out the process.
1. Each group (or at least some, depending on time) will present their findings to the class in 2 minutes or less.
1. Students should use the "CyberSecurity Notes WS" document to take notes for use in studying for the Unit 3 assessment.

## Wrap Up (5 min)

Visit the Top 10 Malware January 2019 report.

Visit the us-cert.gov report on Ransomware.

What is ransomware?

How can you protect yourself?

• What security concerns does this raise?
• What can be done to protect student data?

## Guidance for Practice Questions - Question Set 14

Questions in the AP Classroom Question Bank may be used for summative purposes.

Sixty of the 80 questions are restricted to teacher access.  The remaining 20 questions are from public resources.

Questions are identified by their initial phrases.

A certain social media Web site allows users to...

A retailer that sells footwear maintains a single

When a cellular telephone user places a call, the

Many Web browsers allow users to open anonymous...

Which of the following has the greatest potential

Which of the following is considered an unethical

# Homework:

Real World Connection: Protecting your Computer

Choose one of the following articles to read, based on the operating system you have running on one of your home computers, or the computer you normally use.

1. Does the computer have anti-virus software installed?

If yes, answer the following questions:

1. What is the name of the anti-virus software installed on the computer?
2. Is the anti-virus software on the computer up to date?
3. What features does the anti-virus software provide?

If no, do the following:

1. Find at least two different anti-virus programs for your operating system (one that is free and one that you must purchase).
2. Compare and contrast the anti-virus programs based on the features that they offer.
3. Talk to an adult about installing anti-virus software on your computer if you own one.
4. Does the computer have a firewall enabled?
5. Is the operating system up to date? Which version of the operating system is the computer currently running?
6. What other security measures have been taken to protect the computer?

Optional: Use this extended checklist to enhance the security of your computer.

http://m.wikihow.com/Secure-Your-PC

## Formative Assessment

The teacher will see where the students place the cyber attacks as they read about them on the impact graph and give appropriate feedback.

The teacher will monitor the research on cyber attacks and check for accurate information.

The teacher will clarify misconceptions that become evident during the group presentations.

## Summative Assessment

Students will complete a journal entry by responding to questions about their personal and school related data being accessible through the Internet.

## Lesson Summary

Summary

Students are introduced to the topic of cryptography and learn to perform two encryption techniques. The students will identify the role of the algorithm and key in the encryption process. Students will use abstraction to see the general process used in symmetric encryption. The students will consider the strength of ciphers and the importance of keeping the key a secret.

Outcomes

• Students will understand how encryption is used to keep data secure.
• Students will learn how encrypting and decrypting data is accomplished using an algorithm and a key.
• Students will understand why the key must be kept a secret.

Overview

1. Getting Started (5 min) - Journal
2. Introduction to Content (15 min)
1. Lesson Motivation [5 min]
2. Presenting the Key Concepts [10 min]
3. Guided Activities (25 min)
1. Practice [15 min]
2. Follow Up: Analyzing the Strength of Ciphers [5 min]
3. Follow Up: Defining Symmetric Encryption and Seeing the Abstraction in Symmetric Encryption Systems [5 min]
4. Wrap Up (5 min) - Journal

## CSP Objectives

• EU AAP-2 - The way statements are sequenced and combined in a program determines the computed result. Programs incorporate iteration and selection constructs to represent repetition and make decisions to handle varied input values.
• LO AAP-2.A - Express an algorithm that uses sequencing without using a programming language.
• LO AAP-2.L - Compare multiple algorithms to determine if they yield the same side effect or result.
• LO AAP-2.M - For algorithms: a. Create algorithms. b. Combine and modify existing algorithms.
• LO AAP-2.O - For algorithms involving elements of a list: a. Write iteration statements to traverse a list. b. Determine the result of an algorithm that includes list traversals.
• EU IOC-2 - The use of computing innovations may involve risks to your personal safety and identity.
• LO IOC-2.B - Explain how computing resources can be protected and can be misused.

## Math Common Core Practice:

• MP1: Make sense of problems and persevere in solving them.
• MP2: Reason abstractly and quantitatively.
• MP8: Look for and express regularity in repeated reasoning.

## Common Core ELA:

• RST 12.4 - Determine the meaning of symbols, key terms, and other domain-specific words and phrases

## NGSS Practices:

• 5. Using mathematics and computational thinking

## Key Concepts

• Encryption is used to keep data secure as it is transmitted through the Internet.
• Symmetric encryption involves encrypting and decrypting data using an algorithm and a key.
• Encryption algorithms themselves are standardized (well known), so the key must be kept secret.

## Essential Questions

• How is cybersecurity impacting the ever increasing number of Internet users?

## Teacher Resources

Student computer usage for this lesson is: optional

In the Lesson Resources folder:

• "Cryptography Partner Practice": A worksheet for the students
• "Cipher Python Project": A worksheet with instructions for a simple Python project
• "Cipher Python Project Rubric": The rubric for the Cipher project

Optional: Lesson slides with the key questions, encryption demos, and diagrams (the teacher could simply read the questions and present demos and diagrams by writing on a board).

For examples, consider reviewing The Code Book by Simon Singh.

# Getting Started (5 min)

Journal:

• Why does the website require you to provide a username and password?

# Introduction to Content (15 min)

## Lesson Motivation  [5 min]

• Present the scenario: “Alice would like to send a message to her friend Li in China, but she wants to keep it secret from everybody else.”
• Ask the students: “If Alice sends the message to Li by email over the Internet, will her message remain secret?”
• Student responses should bring up the architecture and trust model of the Internet to show that Alice’s message could be intercepted along the way, since it will pass through many devices before it ends up at Li’s computer.

## Present the Key Concepts [10 min]

Tell the students, “This problem is not a new one. Throughout history, people, including government and military officials and personnel, business owners, and others, have wanted to send secret messages to someone but worried that the message could be intercepted along the way.”

There are two ways to try to keep the message secret: Steganography and Cryptography.

Explain the basic difference between the two.

• Steganography is when a message is "hiding in plain sight". Examples: Writing something in invisible ink that can be revealed with a special type of light.
• Cryptography is when a message is modified in a way that hides the meaning of the message. For example, the letters are replaced with symbols that someone else would not understand.

Present two different encryption techniques, showing one example of each.

An alternative to this lecture portion above is to have students independently study the same concepts using a reading, video, or online learning tool. Here are some suggested resources:

Summarize with this overview: "Each encryption scheme involves an algorithm and a key. The algorithm is the set of steps that you follow to accomplish the encryption. The key is the secret piece of information that is needed to know exactly how to apply the algorithm in this case. This allows you to securely send encoded information across the Internet and decode it when it arrives. Some codes are more secure than others."

# Guided Activities (25 min)

## Practice [15 min]

Have the students pair up and practice sending each other encrypted messages, then decrypting them to make sure they end up with the correct message.

A worksheet called "Cryptography Partner Practice" is provided in the Lesson Resources folder.

1. Each student gets to write two short messages that they will encrypt and send to their partner.
2. First message: Transposition: Use the rail fence algorithm. You must agree on the number of rails to use (this will be the “key”).
3. Second message: Substitution: Use the shift substitution cipher algorithm. You must agree on the amount to shift (this will be the “key”).
4. For each message, pass it to your partner and have them decrypt it using the agreed upon algorithm and key. Have them read back the decrypted message to make sure they decrypted it correctly.

## Follow Up: Analyzing the Strength of Ciphers [5 min]

Ask the students: “How difficult would it be to crack a message that was encrypted using the Caesar (shift) cipher if you didn’t know the key? How would you do it?” (Easy, try each of the 25 possible shifts.)

Present: There are two ways to increase the strength of encryption:

Option #1: Increase the number of possible keys.

A general substitution (not limiting to just a shift) dramatically increases the number of keys. The number of keys in this case is the number of permutations (different orderings) of the 26 letters in the alphabet. This can be computed by multiplying the 26 options for the first letter in the cipheralphabet, by the 25 remaining options for the 2nd letter, 24 remaining options for the 3rd letter, etc. (26! or 26 factorial).

The answer: 4.032914e x 1026 keys (Google will calculate it for you).

This analysis makes it seem as though a substitution cipher would be unbreakable, but clever people have invented tricks (e.g., frequency analysis) that can be used so you don't have to try all of the different keys.

Option #2: Use a better algorithm.

For example, use a polyalphabetic cipher that combines multiple cipher alphabets.

(If time allows, you can have students explore other ciphers. For further study, see Khan Academy or The Code Book by Simon Singh.)

## Follow Up: Defining Symmetric Encryption and Seeing the Abstraction in Symmetric Encryption Systems [5 min]

Present a diagram that shows high-level view of the encryption and decryption process (see The Code Book, p. 11).

1. Identify this as an example of abstraction. (You can ask the students to try to explain why.) Example: This is abstraction because it shows the general process of encryption and decryption using any key or algorithm. It omits the details of the specific algorithm and the type of key.
2. Tell the students, “The types of encryption you learned today are called “symmetric”. Why do you think they are called “symmetric”?  (The same key is used to encrypt and decrypt. You use the algorithm to encrypt, and then reverse it to decrypt.)
3. What do you think it would mean for encryption to be asymmetric (non-symmetric)? (foreshadowing the next lesson)

# Wrap Up (5 min)

Journal:

• What is the role of the algorithm in the encryption process? What is the role of the key?
• Which one of these, the algorithm or the key, is more important to keep secret? Why?

# Optional Project for additional Python Practice

Use the "Cipher Python Project" worksheet in the Lesson Resources folder. Students are tasked to create a simple Caesar cipher program that uses ASCII values to shift messages by a certain letter. The rubric for this project is also in the Lesson Resources folder.

# Homework (Optional): Choose one of the following or let each student choose which one to complete.

1. Computer Encryption: Use bitwise XOR to do substitution cipher (see The Code Book, p. 247)
2. Students read a historical account that involves encryption (Mary, Queen of Scots) http://www.nationalarchives.gov.uk/spies/ciphers/mary/ (After reading the introduction, click on the links below the picture for “Mary’s ciphers” and “The Babington Plot”)
3. Students read about cryptanalysis and learn about the frequency analysis technique. Try using it on an encryption puzzle..
1. An example of breaking a substitution cipher: http://www-math.ucdenver.edu/~wcherowi/courses/m5410/exsubcip.html
2. Try deciphering an encrypted message using the techniques you read about: http://cryptogram.org/solve_cipher.html#contents

## Formative Assessment

The teacher will evaluate student responses to the journal entries, class discussion questions, and the students performance during the encryption practice.

## Lesson Summary

Summary

In this lesson, students will learn two solutions to the key distribution problem and the mathematical foundations behind these solutions. They will make connections between encryption, the use of SSL/TLS in web browsers, and the use of digital certificates. Students will recognize the value of open standards used in modern cryptography.

Outcomes

• Students will understand the impact of the key distribution problem on secure communication.
• Students will understand that a carefully designed one-way mathematical function allows people to exchange keys or use public keys to solve the key distribution problem.
• Students will understand that digital certificates are used for authentication, and that these certificates rely on the trust model: the certificate authorities are being trusted to provide accurate information.

Overview

Session 1

1. Getting Started (5 min) - Students journal on the safety of transactions made online and the role of cryptography,
2. Introduction to Content (15 min) - The Key Distribution problem and mathematical modulus are presented and discussed.
3. Guided Activities (25 min) - Students learn about double encryption through analogies and a group activity.
4. Wrap Up (5 min) - Journaling on sharing secrets.

Session 2

1. Getting Started (5 min) - Students journal on how Diffie's solution benefits them.
2. Introduction to Content (5 min) - Students discuss Diffie's solution to the Key Distribution problem
3. Guided Activities (35 min) - Students Role Play and Journal about Public Key Encryption.
4. Wrap Up (5 min) - Journaling about the positive/negative aspects of Public Key Encryption

## CSP Objectives

• EU DAT-1 - The way a computer represents data internally is different from the way the data is interpreted and displayed for the user. Programs are used to translate data into a representation more easily understood by people.
• LO DAT-1.A - Explain how data can be represented using bits.
• EU AAP-2 - The way statements are sequenced and combined in a program determines the computed result. Programs incorporate iteration and selection constructs to represent repetition and make decisions to handle varied input values.
• LO AAP-2.C - Evaluate expressions that use arithmetic operators.
• EU AAP-4 - There exist problems that computers cannot solve, and even when a computer can solve a problem, it may not be able to do so in a reasonable amount of time.
• LO AAP-4.A - For determining the efficiency of an algorithm: a. Explain the difference between algorithms that run in reasonable time and those that do not. b. Identify situations where a heuristic solution may be more appropriate.
• EU IOC-2 - The use of computing innovations may involve risks to your personal safety and identity.
• LO IOC-2.B - Explain how computing resources can be protected and can be misused.

## Essential Questions

• How are programs developed to help people, organizations or society solve problems?
• How is cybersecurity impacting the ever increasing number of Internet users?

## Teacher Resources

Student computer usage for this lesson is: optional

In the Lesson Resources folder:

• Lesson slides
• Worksheet for Key Exchange Activity
• Script for Public Key Encryption 3 Act Play

# Session 1

## Getting Started (5 min)

Students should answer the following questions in their journals:

• What types of online activities require information to be kept secret when it is transmitted?
• How does cryptography allow for information to be kept secret when it is transmitted?

## Introduction to Content (15 min)

Suggested Review

• Have students present their solutions to the "Computer Encryption" homework from Lesson 2-12 and/or connect back to the previous lesson by posing the question: "Do you think computers actually use the encryption algorithms we learned last class?"
• This discussion should lead to the question of what algorithms computers actually use. In the 1970s, the US government chose DES as the standard encryption algorithm that everybody could use. It has been updated to AES, which is a stronger algorithm, but DES and AES are very similar.
• The teacher should make the point that at a high level, DES/AES are symmetric encryption algorithms that work on the same basic principle of the simple algorithms we looked at in the previous lesson.
• The teacher can leave it at that, or optionally present some brief details on DES/AES. One option is to show the first minute or two of this visualization video and talk over it: http://youtu.be/mlzxpkdXP58

Motivation: Present the Key Distribution Problem:

Introduce the following topic. Allow for discussion among the class about possible solutions to the problem presented.

• Alice wants to send Li some secret information over the Internet. We know that she can encrypt the information before sending it, but how will Li know what key Alice used to encrypt the message?
• This is called the Key Distribution Problem and it has been around as long as encryption has. A whole business was developed around this challenge: people were paid to go around the world delivering briefcases full of encryption keys. This distribution process obviously can be very expensive and is completely unpractical for the average person. For a long time, nobody thought that the key distribution problem could be solved algorithmically.

After the class has come up with some ideas, reveal a solution to the problem that was found using math.

Present Key Information: Dreamers to the Rescue – Two men, two solutions, one important mathematical idea.

• Despite everybody telling them they were crazy and hopeless, Martin Hellman and Whitfield Diffie teamed up to try to solve the Key Distribution Problem. Amazingly, they each came up with a solution, both of which can be used to solve the problem.
• Introduce One-Way Functions: Both solutions use a mathematical concept called “one-way functions”.  Most functions we are familiar with are “two-way": that is, they can easily be applied in either a forward or a reverse direction. For example, if f(x) = 2x, then it is easy to see that f(5) would be 2(5) or 10. It is also easy to see that if f(x) = 10, then 2x = 10, so x must be 5. One-way functions are different in that they are easy to use in one direction, but are very hard to reverse.
• Key Distribution – Solution #1 – Hellman’s Idea – Key Exchange Protocol

## Guided Activities (25 min)

### Analogy (10 min)

1. To help with the explanation of the topic, start with an analogy that uses different colors of paint.
2. The real system relies on a mathematical operation called modulus (or clock arithmetic), which is when you divide two numbers and find the remainder.
• Use a clock to visually demonstrate the operation. (The number mod 12 gives you the time)
• Show how to do modulus by using either long division, a calculator, or Google. (Consider this: If you know the number you divided by, and you know the remainder, can you easily figure out what the original number was? )
• Alternatively, show the next section of the video: https://www.youtube.com/watch?v=YEBfamv-_do  [4:20 - 6:18]

The system also uses powers (base/exponent). Very briefly review power notation.

### Group Activity (15 min)

1. Students are paired up, and then join another pair to form a group of four.
2. Using either a set of clear directions or an online widget, one pair performs the key exchange using the Yx(mod P) expression, while the other pair listens in.  They then switch roles. They should see that the key is established while sharing information publicly, but the key itself is kept secret.

## Wrap Up (5 min)

Students should answer this question in their journals:

• How can two people establish a shared secret in public?

## Suggested Homework:

Research Hellman and Diffie’s work on public-key exchange, identify the big ideas of CS Principles that show up, and provide specific examples of how they are related to what you find out about Hellman and Diffie's work.  Alternately, read about the British group that developed the same solution as Hellman and Diffie's to public key encryption in secrecy (http://cryptome.org/ukpk-alt.htm).

# Session 2

## Getting Started (5 min)

Students will read the following question and record their thoughts in their journals:

• Whitfield Diffie said that he wanted to solve the key distribution problem for benefit of "ordinary people," as opposed to just governments and corporations. How do you and I benefit from his team's solutions to the Key Distribution Problem?

Have students present ideas from their journal entries. Use this as a way to review the Key Distribution Problem, and the team that tackled the problem.

## Introduction to Content (5 min)

Present Diffie’s Solution - Public Key Cryptography

• The Idea: Encrypt with one key (public key), decrypt with a second key (private key)
• For further clarification, use this analogy:
• Analogy with Physical Locks – Person B gives out open padlocks (public key) to anybody who wants to send him or her something secret. Person A just puts the secret in a box, and shuts the padlock (easy to do!). When Person B receives the box, they use the combination (private key) to unlock it.
• This is called “Asymmetric Encryption” since it uses two different keys.
• Consider what happens when you go to a "secure" website to check out when you are finished shopping at an online store. Your browser says "https" and some show a picture of a lock. The system, called SSL (Secure Sockets Layer) or the updated version TLS (Transport Layer Security) takes advantage of Diffie's system.

## Guided Activities (35 min)

### Part 1 (20 min) - Role Play

Have students act out three short scenes (see "Public Key Encryption Plays") in order to illustrate how the system works. (It is advisable to select "dramatic" students to fill the four roles.)

Roles

• Customer
• Store
• Store Impersonator
• Certificate Authority

Overview

• Act 1: The customer and store use public key encryption to complete an online purchase using a credit card. (All seems well, but the next act will have a twist!)
• Act 2: The store impersonator distracts the store and jumps in, steals the credit card info. (After this, stop for a minute and ask the students to explain what the problem is)
• Act 3: Repeat Act 2, except that now the customer asks the Certificate Authority to verify the public key. The impersonator is revealed as a fraud, then the real store completes the transaction with the CA verifying.

Follow Up question to ask the students: Who do you have to trust for this system to work? (2 min)

• Sample Answer: The Certificate Authority. You are trusting that they are giving you valid information so you can verify the identity of others. (A student may ask how you know the certificate authority is not being impersonated. The answer is that the public key of the certificate authority is saved in your browser so you can verify their identify yourself. )

### Optional Section on Mathematical Foundation

What are the mathematical details that enable this idea of work? (Don't worry, we are not going to fully answer this!)

• Diffie didn’t actually figure out the math to make this actually work, he just had the key idea (Example of Abstraction!) He put the idea out there for others to figure out the details of the math that would make it work (Example of Collaboration!)
• One system (RSA) multiplies prime numbers as part of the one way function. It is easy to multiply two prime numbers, but it is very hard to determine the factors of the product (if you didn't already know them).
• Give the students a couple of problems to illustrate this.
• The two primes that you multiply are essentially the "private key". The product is the "public key".
• This works in practice because the numbers used are huge, making the factoring process extremely difficult and time consuming, even with a large amount of computational power.

Discussion: Do “Open Standards” make sense in the world of Cryptography?

The systems of encryption used on the web have been "standardized" (meaning that everyone agrees to use the same systems) so that computers all over the world can communicate with each other. These standardized systems could be "proprietary" (meaning the details are kept secret), or they can be "open" (meaning the details are shared for anybody to see).

### Part 2 (15 min) - Think-Pair-Share

Students will Think-Pair-Share about the following prompts:

• If cryptography is all about secrecy, then does it make sense to have open standards of encryption? List all the pros and cons that you can think of for open standards.
• Open standards fuel the growth of the Internet. Why? (consider both hardware and software)

Possible responses

Benefits of open encryption

• People can independently verify that the algorithm is strong, secure, and doesn’t have vulnerabilities.
• People can make sure there are no “back doors” in the algorithm that let certain people spy on them even without the key.

Benefits of open standards

- The bigger picture: Open Internet standards are the cornerstone of the Internet’s success. They enable its existence, facilitate its growth, and provide a platform that supports creativity, as well as social and economic opportunity for its billions of users. Open standards are implemented around the world in all kinds of Internet products and services. https://www.internetsociety.org/policybriefs/openstandards

Note: Heartbleed vulnerability is a good example of something that was eventually caught because of open standards. (This could be a homework assignment to read about it)

Drawbacks

• Any cyber-criminal can look at the algorithm and try to find a vulnerability to exploit.
• People may assume that because it is open, all the vulnerabilities have been found and plugged when that is not necessarily true.

## Wrap Up (5 min)

Students should read this question and record their thoughts in their journals:

•  "Open standards result in strong security". Do you agree or disagree with this statement? Give specific reasons to back up your position.

## Guidance for Practice Questions - Question Set 15

Questions in the AP Classroom Question Bank may be used for summative purposes.

Sixty of the 80 questions are restricted to teacher access.  The remaining 20 questions are from public resources.

Questions are identified by their initial phrases.

What is the minimum number of connections that ...

Which of the following are true statements abou...

Which of the following best describes a Distrib...

Which of the following is LEAST likely to indic...

Which of the following statements about securit...

## Optional Homework:

Read about Heartbleed vulnerability in SSL. Reflect on how open standards relate to this.

## Extensions:

RSA Encryption Algorithm Video: http://youtu.be/M7kEpw1tn50

## Formative Assessment

The teacher will observe and evaluate student responses to journal entries, class discussion questions, and class activities.

## Lesson Summary

Summary

This lesson will increase student awareness of the concept that there are dangers associated with Internet usage. It addresses Internet Security with issues inherent to Internet usage: viruses, worms, Trojan horses, and identity theft. The primary objective of this lesson is to equip students with knowledge that will enable them to make responsible choices regarding their Internet use, to prevent security risks. This lesson introduces key vocabulary, discusses Internet security and provides students the opportunity to explore the causes and effects of common security problems.

## CSP Objectives

• EU CSN-1 - Computer systems and networks facilitate how data are transferred.
• LO CSN-1.A - Explain how computing devices work together in a network.
• LO CSN-1.B - Explain how the Internet works.
• LO CSN-1.C - Explain how data are sent through the Internet via packets.
• EU IOC-2 - The use of computing innovations may involve risks to your personal safety and identity.
• LO IOC-2.B - Explain how computing resources can be protected and can be misused.
• LO IOC-2.C - Explain how unauthorized access to computing resources is gained.

## Key Concepts

Students will:

• Learn about the different types of malicious code and how to take prevention steps to safeguard systems, data, and identity.

• Give advice on secure cyber practices.

Outcomes

• Students will be able to identify key general attributes of the threats to the security of computers and information via the Internet such as viruses, worms, and Trojan Horses.
• Students will understand critical attributes of the sources, and consequences to individuals and society, of identity theft.
• Students will understand how to protect themselves and their computers from external threats.
• Students will develop a strategy to inform others of the security risks inherent to Internet usage.

## Essential Questions

• How is cybersecurity impacting the ever increasing number of Internet users?
• What are some potential beneficial and harmful effects of computing?
• What are different types of malicious code and what is the intention of each attack?
• How can internet users protect themselves from malicious code and prevent such cybercrime attacks?
• How can internet users follow secure practices to reduce the risk of identity theft?

## Teacher Resources

Student computer usage for this lesson is: required

Teacher's resources:

• NA SAIT Security Video - Malicious Code - Malware Video - https://www.youtube.com/watch?v=7wAHZLFiY-E
• What to do if you are a victim of Identity Theft: Possible Answers
• The FTC’s website is a one-stop resource to both learn about identity theft and walk you through the appropriate actions if your identity is stolen: http://www.ftc.gov/bcp/edu/microsites/idtheft/
• Some possible steps if your identity is stolen:
• Report the identity theft to the three major credit bureaus: Experian, TransUnion, and Equifax.
• File a police report with local law enforcement.
• Report the theft to the FTC online at www.ftc.gov/idtheft or by phoning 1-877-ID-THEFT (1-877-438-4338).
• Possible ways for Deterring Identity Theft:
• Shred financial documents that are not being kept for safeguarding. [This allows a teacher to cover the kind of information that should be held and for how long (in years). It also allows a teacher to cover what documents are best kept in a safe deposit box, a home safe, regular home files, etc.]
• Do not carry around your Social Security card in your wallet.
• Do not give out personal information over the phone or over the Internet unless you are absolutely sure who you are dealing with.
• Choose computer and electronic passwords with care by avoiding birth dates, your Social Security number, your mother’s last name, etc.
• Try not to have your postal mail pile up in your mailbox for several days; if you are going to be away for a few days, have your mail held at the post office until you return.
• Be suspicious about regular bills that do not arrive on time, denials of credit for no apparent reason, calls or letters about purchases you did not make, charges on your financial statements that you do not recognize.

Students' resources:

• writing journals
• blogs

# Session 1

## Getting Started (10 min)

1. Journal: How might malicious code be a threat to Internet security?
• Possible answers to bring up: identity theft, data theft, stealing money, breaking down other computers, turning other computers into bots to create more problems, etc.
2. Introduce the topic/Discussion: Inform the students that today they will be talking about Internet security and participating in discussions about the dangers of viruses and, identity theft and malware along with resources and prevention tips.
• Malicious code is a programming code designed with a harmful intent (to hack, cause damage, etc.). With Internet usage comes rights and responsibilities to protect your computer from malicious code. Malicious code causes millions of dollars in damage every year.
• How can malicious code spread across many computers so quickly?
• Examine the idea of interconnectedness.
• Look together at the Digital Attack Map which displays global DDoS activity on any given day. Attacks are displayed as dotted lines, scaled to size, and placed according to the source and destination countries of the attack traffic when known. Have students react to the histogram at the bottom of the map to explore historical data and select a country to view DDoS activity to or from that country at http://www.digitalattackmap.com/understanding-ddos/ .
3. Introduce key vocabulary - have students crowdsource definitions or look up separately and compare.
• Computer virus
• Spyware
• Ransomware
• Bot
• Hacker
• Malware

## Guided Activities (30 min) - Malicious Code and Identity Theft

1. Play the NA SAIT Security Video: "Malicious Code - Malware" at https://www.youtube.com/watch?v=7wAHZLFiY-E ( 3 minutes, from 2013)
• AnnMarie Keim, IT Specialist, discusses the concepts of Internet Security and introduces the different types of malicious code and how to protect from this type of cybercrime. Keep your system updated, use antivirus and firewall. Backup important files.
2. Review the following words from previous lessons:
• routers
• firewalls
3. Discuss: Is malicious code the only way to cause harm on the Internet? (no)
• https://vimeo.com/63422786 (0:30) Google mini-video to show what phishing is, using a brick through a glass window example to get attention.
• Talk about social hacking, using ordinary everyday life tricks to get information like looking over somebody’s shoulder when they type their password, sneaking inside of a locked door before it closes, etc. Point out that it is a combination of people, software and hardware that are both the problem and the solution to Internet security.
4. Students work in groups to explain how unauthorized access to computing resources is obtained and what can be done to protect against them in terms of human behavior, software, and computer hardware. Student groups could create a blog post about their topic to share at the end of class or report using another method. Suggested access methods to address include:
• Computer viruses
• Virus hoaxes
• Worms
• Trojan horses
• identity theft
• Phishing scams
• Cellphone and texting scams
• Ransomware

# Wrap Up (5 min)

Students will read the following prompt and respond in their journals:

• The only 100% way to prevent malicious code attacks and identity theft is to not go on the Internet. Do you see that as a viable solution for individuals? Corporations? Support your answer.

Consider the following questions and discuss answers as a class:

1. Have you or someone you’ve known experienced a virus or malware? What was the outcome? What did you take away from this experience?
• Cover the following:
• Time and Money spent – (by corporations and by an individual to protect computer assets)
• What were the consequences?
• What did the victim go through?
2. How can you avoid malicious code?
• Anti-virus software
• Anti-spyware software
• Restore points
• Careful use of email

# Homework (optional)

On your home computer, see how vulnerable you are to malware and identity theft:

• Carry out some remedies and prevention tips (minimum of three tasks) that you learned today.
• Be prepared to share in the next class

# Extensions/Differentiation:

If there is additional time, watch one of the TED talks

• James Lyne: Everyday cybercrime -- and what you can do about it (17:26)
• The Internet is on fire | Mikko Hypponen | TEDxBrussels (19:16)

Students can create an "Identity Theft Prevention Action Plan," including a purpose and list of ten guidelines, to share with family and friends after they have researched prevention tips on the FTC website.

• Students may use their choice of the following Web 2.0 websites to create their action plan:
• Students will embed their action plan to a blog post in order to share with teacher, classmates, friends, and family. Students should email friends and family (minimum of three people with the teacher cc'd) the link to this blog post on Identity Theft Prevention Action Plan (title of blog post and subject line of email).

## Formative Assessment

• Journal writings
• Introduction question prompts
• Wrap-up question prompt

• Class discussions - answers, input, and further inquiry by students

• Identity theft prevention plan

## Summative Assessment

Unit Assessment and Investigate/Explore Performance Project – at end of unit.

## Lesson Summary

Data is stored and transmitted online efficiently using many different kinds of hardware and software to send it quickly and accurately. Data can be compressed to take up less storage room and transmission time and, at the core, the entire system is made up of simple circuits that work with binary information that flows at an incredible speed all around the world. The security and privacy of this constant flow of data deserve understanding and attention. Students will investigate different areas of privacy and share with the class.

This flexible lesson includes additional material if the teacher would like the opportunity to reteach key concepts such as binary, abstraction, Internet functionality and also teachers the layers of hardware abstraction from transistors and logic gates up to computing devices.

The accompanying assessment can be used in class or as homework. (20 min) optional

## CSP Objectives

• EU DAT-1 - The way a computer represents data internally is different from the way the data is interpreted and displayed for the user. Programs are used to translate data into a representation more easily understood by people.
• LO DAT-1.A - Explain how data can be represented using bits.
• LO DAT-1.C - For binary numbers: a. Calculate the binary (base 2) equivalent of a positive integer (base 10) and vice versa. b. Compare and order binary numbers.
• LO DAT-1.D - Compare data compression algorithms to determine which is best in a particular context.
• EU CSN-1 - Computer systems and networks facilitate how data are transferred.
• LO CSN-1.B - Explain how the Internet works.
• LO CSN-1.C - Explain how data are sent through the Internet via packets.
• LO CSN-1.E - For fault-tolerant systems, like the Internet: a. Describe the benefits of fault tolerance. b. Explain how a given system is fault-tolerant. c. Identify vulnerabilities to failure in a system.

## Math Common Core Practice:

• MP2: Reason abstractly and quantitatively.
• MP6: Attend to precision.
• MP7: Look for and make use of structure.

## Common Core Math:

• N-Q.1-3: Reason quantitatively and use units to solve problems
• A-CED.1-4: Create equations that describe numbers or relationships

## Common Core ELA:

• RST 12.3 - Precisely follow a complex multistep procedure

## NGSS Practices:

• 4. Analyzing and interpreting data
• 5. Using mathematics and computational thinking

## NGSS Content:

• HS-ETS1-2. Design a solution to a complex real-world problem by breaking it down into smaller, more manageable problems that can be solved through engineering.

## Teacher Resources

Student computer usage for this lesson is: required

The Computer Science Field Guide http://csfieldguide.org.nz

Coding and compression: http://csfieldguide.org.nz/en/chapters/coding-compression.html

Data representation: http://csfieldguide.org.nz/en/chapters/data-representation.html

Use the binary number calculator to check conversion calculations

How computer memory works (5:05) http://ed.ted.com/lessons/how-computer-memory-works-kanawat-senanan

Presentations: Unit3Lesson14_InternetData_Presentation, Unit3Lesson14LogicGates_Presentation.

Worksheets: Accompanying student notes to be filled in. Unit3Lesson14_InternetData_StudentHandout, Unit3Lesson14LogicGates_Handout. Also Unit3Lesson14_InternetData_ReviewSection

## Journal (5 min)

How does information get from one computing device to another using the Internet? (also on Slide 1 of the Unit3 Lesson14_InternetData_Presentation)

Slides 2-3 review the basic steps to sending information online:

• Information is encoded in binary, then, (check to see if students remember how to do decimal to binary conversions)
• divided up into packets and sent
• decoded into words, pictures, etc when it arrives.

This is a review of unit 3. Pair, share and discuss. Identify weak areas of student understanding.

## Review Presentation on Binary and the Internet ( 20 min)

If students need additional review: provide the handout: Unit3Lesson14_InternetData_ReviewSection (to accompany slides 4-9) and continue with the presentation, otherwise use the handout as an assessment.

• SLIDE 4: Fill in the blanks using words on the handout to describe the important features of internet communication.
• SLIDE 5: define protocol and ISP
• SLIDE 6: each device has an IP address that is looked up using the DNS
• SLIDE 7: packets are routed, paths are redundant
• SLIDE 8: review binary codes and number conversion
• SLIDE 9: answers to binary questions from SLIDE 8

## Activity 1: Data compression (10 min)

Distribute Unit3Lesson14internetData_StudentHandout (slides 10-11) on data compression and abstractions from low level to high level with notes to accompany the video how computer memory works (5:05)

• SLIDE 10: compression saves time and storage. Look up lossy and lossless compressions (Lossless compression reduces the number of bits used and trasmitted, which can be reconstructed to the original data without any approximation; Lossy compression significantly reduces the number of bits at the cost of accurately reconstructing the original data)
• SLIDE 11: abstractions from low level to high level
• SLIDE 12: different file formats have characteristics for their intended uses and different media have advantages and disadvantages for their intended use (cost, stability, peformance, size, etc)

## Activity 2: Data Security and Privacy

Say:  To protect ourselves online we need to understand some facts about how data is collected and used.  Assign each of the following to a pair of students.  Each pair is to prepare and present a 30 second (2 or 3 sentences) explanation for why their fact is most important.  After two minutes give each pair a chance to present their explanation.

1. Devices like cell phones and IoT sensors collect user information including their locations, travel patterns, and the time spent in a location.
2. Data may be collected and used by governments, corporations or other institutions.
3. Information about users can be obtained by aggregating data from multiple sources building a multi-dimensional understanding of the person, their habits, their health, and more.
4. Information about a user including PII can be used to provide a better service on the internet such as simplified online purchases.
5. Governments have established laws requiring commercial and governmental organizations to protect user privacy.
6. User privacy is at greater risk when the protections offered by these laws are ignored.
7. Information placed online such as in social media may be reposted and disseminated in harmful ways the original user never intended.
8. Information placed online may be very difficult to control or delete.
9. Information about a person from different online sources might be combined in a way to identify the person and to determine additional facts about the person.
10. A person's PII can be used to steal that person's identity, their money or even to stalk or threaten them.

## Activity 3: Presentation on Logic gates and hardware abstractions (20 min)

Distribute Student handout: Unit3Lesson14LogicGatesHandout.docx

1. Prompt: Ask what really goes on inside of computers.
2. Computers are fast and accurate. To show how quickly they can do caclulations, demonstrate google search engine’s ability to instantly provide the answer to complicated calculations like 271839 to the 23rd power
3. All data is in binary so all calculations must be in binary
4. Inside each chip are circuits.
5. If you could see inside a chip you’d see the communication lines for the bits, like roadways, and the processing units like buildings
6. Abstractions: the CPU is made of circuits, circuits are made of logic gates.
7. Follow bits through a calculation. The number 7 is pressed on the keyboard sending 00000111 to the CPU to be processed
8. The algorithm for addition is invoked when the “+” sign is pressed and will start up when the 2nd number is entered.
9. 21 is pressed followed by = and the addition algorithm starts with the rightmost bits and adds up each column
10. addition is done with logic circuits. Logic circuits are made up of logic gates. There are picture symbols for each gate
11. looking at the AND gate, how many different input values can A have? How many different output values can Q have?
12. Use a truth table to show the inputs and outputs of a logic gate
13. The not gate, or inverter, changes a signal to its opposite
14. There are logic gates in an addition circuit
15. How logic gates add 2 digits
16. How logic gates add 3 digits
17. How the OR gate works
18. The deeper you look into what is happening the better you can understand what is really going on inside of a computing device.
19. Diagram of layers of abstraction from transistors up to computing devices.
20. Sample lotic questions
21. Sample AP ® type question
22. Career connections in circuit design

## Wrap Up (5 min)

Assessment (20 min) optional or can be used as homework.

Also available Logic Gates additional practice handout and informational article.

## Guidance for Practice Questions - Question Set 16

Questions in the AP Classroom Question Bank may be used for summative purposes.

Sixty of the 80 questions are restricted to teacher access.  The remaining 20 questions are from public resources.

Questions are identified by their initial phrases.

A new bank plans to make customer convenience a...

## Options for Differentiated Instruction

More than any other lesson so far, this lesson should be customized to meet the needs of the students. If they have a background in electronics and logic circuits from science or STEM classes, or have a firm grasp of binary number conversion and how the internet works, these sections of the lesson can serve as a very quick review skipping past the slides with extra detail.

For advanced students: Use the Unit 3 Lesson 14 assessment and the Unit 3 Lesson 14 Data on the Internet - Review Section as summative assessments after a brief review.

For students who do not have this background knowledge, use the presentations and notes.

## Formative Assessment

Notes and exercises for binary encoding, data compression, logic circuits, how the internet works and layers of hardware abstraction.

## Summative Assessment

Unit 3 Lesson 14 Summative Assessment

and

Unit 3 Lesson 14 Data on the Internet - Review Section

can be used as a formative or summative assessment.