Students complete a scheduling challenge three times to explore the need for addressing messages online. Students first complete a challenge where they are allowed to talk to one another to fill out a weekly schedule. They then complete the challenge again, but this time they can only communicate using messages which are "broadcasted" or sent to everyone in the same group. This challenge forces students to develop shared rules for communicating to complete the scheduling activity a second and then third time. The wrap up helps students connect their experiences to real-life rules, or protocols, used on the Internet for addressing messages.
Students will be able to:
Now that students have explored what it takes to link devices on a network, they are ready to learn how devices communicate with each other. Prior to this lesson, students have only interacted with point-to-point communication. In this lesson, students will instead "broadcast" every message to every person in the same group. This closely mimics a real life problem that computer scientists had to solve: With all the bits passing through many computers on a network, how would a computer know if it was the intended recipient? Which computer should get a reply? Internet Protocol (IP) solves a portion of this problem by assigning a unique IP address to each device and standardizing how sender and recipient are identified.
Prompt: Imagine you were in a room with 5 other people, all with the same name as you. What might happen when you start communicating? How could you solve these problems?
Discuss: Have students brainstorm silently, then discuss with a neighbor, and finally share with the whole class.
Discussion Goal: This prompt is meant to foreshadow some of the issues students will face when they use the Internet Simulator. Key points to draw out:
Group: This activity works best with groups of 6, though groups of 5 and 4 are also possible. Rather than a group of 6 and a group of 4, make two groups 5.
Distribute: The Need For Addressing (Activity Guide)
Running Each Week: This lesson has students completing the same activity three times. Each time students need to create a schedule for the week that allows them to see every other member of their group on one of the days. Each time this activity should take roughly 3 - 5 minutes.
Running The First Week: This first run of the activity gives students a feel for how it runs. This will make sure that any confusion when they do the later weeks is caused by the lack of identifying information in the messages and not simply misunderstanding what to do.
Do This: With your group follow the directions given in the box for Week 1
Run Week 1: Have students work on filling out their schedules, agreeing with one another on the days when they will meet. This should take 3 - 5 minutes for all groups to finish. When they're done ask students to quickly check that their schedules actually line up.
Prompt: With your group check that everyone's schedules match. Then discuss what worked well, what made this tricky, if there's anything you want to try differently in Week 2.
Discuss: Students do not need to share out their conversations with the class but circulate the room and listen as they discuss.
Do This: Have students set up their boards for week two in the same way as last time:
Do This: Complete Week 2 without talking! Instead, messages need to be "broadcasted" to the entire group.
Broadcasting Messages: The important part of the challenge is making sure that any information students try to convey must be conveyed to the entire group simultaneously, and it isn't obvious who the sender and recipient are by the method of broadcasting. There are many ways to do this, and we've included a few examples below. Choose a way that works best for your classroom and tell your students what method they'll be using. Here are some example methods:
Week 4: A fourth week is included on the activity guide in case your classroom wants to run the activitiy another time at some point in the lesson. If not feel free to ignore it.
Prompt: Fill out the table on the back side of your sheet. What problems did you have when communicating this time around? What solutions did you create or would you like to try for Week 3?
Discuss: Have students share out some of the challenges they encountered and ways they're going to try to address them the second time around.
Do This: Agree with your group on the set of rules you'd like to try this time around for how to communicate. Then complete Week 3 like the previous two weeks. No talking!
Do This: Based on your experience, take 5 minutes to write down in the rules section the collective rules you and your team would advise using going forward.
Discuss: Have a few volunteers share the rules that their group developed.
Discussion Goal: Use the share out to highlight common features across multiple sets of rules. Namely that:
The goal of this discussion should be to set up the wrap up discussion where students connect their experiences in this lesson to computer science concepts that will be introduced.
Display: The Internet: IP Addresses and DNS (Video). You can stop the video at the 3:23 mark. We watch the second half of this video in a later lesson on DNS.
Prompt: What are the similarities and differences between Internet Protocol (IP) and the addressing rules our class made? Would rules like ours or IP work if they were secret?
Discuss: Have students share their responses with a neighbor before discussing with the whole class.
Discussion Goal: Students should walk away with an understanding that both the class rules and IP are shared, open protocols. Key points:
Journal: Add the following vocab words and definitions to your journal: protocol, IP address, Internet Protocol.
Question: Pick the two statements that are true about the Internet Protocol (IP):
Question: Describe how the Internet Protocol (IP) allows devices to easily connect and communicate on the Internet.