U2Ch1L6_HTTP_DNS
Purpose: Students will understand the role of DNS and HTTP on the Internet.
Vocabulary: HTTP, DNS, Scalable

Journal: Review...1. What is a Packet and what is the role of a Router.

Activity: DNS Slips of Paper

• Hand the students a slip of paper with an IP address on it.
• State: “For the next 5 minutes, your goal is to complete an accurate list of IP addresses and names for all students in the room. You may only talk to one person at a time, but you may exchange as much information with that person as you want.”

Go!
Teacher: As students are working, circulate quietly through the room.

• Approach a student and silently take their IP address slip away from them.
• Give that person a new IP address slip (or a re-used IP address).
• Repeat the above two steps as many times as you can, as you circulate the room.

Journal - Ask Students: Why did I keep taking your IP addresses?
This simulates the fact that a computer’s IP address does not stay the same. For example, a person’s IP address on their phone changes quite frequently as they move around throughout their day and their phone tries to connect to the Internet from different locations.
Ask Students: Can you think up a more efficient way of collecting IP addresses?

Handout – Cheat Sheet “Layers Of the Internet” (Summary of the major concepts that support the internet.).

Video: The Internet: IP Addresses and DNS (4:15 - 5:12) - Question: What is the importance of DNS?

Activity: Go To the DNS – Internet Simulator
When you go to the Internet Simulator now, you will see a “DNS server” attached to the router. In order to communicate with someone else, you must first find their IP address by asking the DNS.
!You may not ask any of the other students for their IP address – you must request it from the DNS!

• The DNS server responds to a text protocol that will give you someone’s IP address. The protocol is:
• GET <hostnameOfPerson>
• For example:
• GET madeline4
• After the DNS has returned an IP address, you can type that IP address into the “To” field, enter a message, and then press “send.”
• Ask each student at least one question (favorite color?) and write it down.

Video: HTTP: - Question: What is the importance of HTTP & Certificates?