From Your Phone to the Sea Floor: teacher key

The Internet, grade 7 edition, written for 7th grade. Follow a message from a browser through home boxes and cell towers to a network of networks and across the ocean in a glass fiber. Learn who coordinates names and numbers.

Read the book. Print this page for the key.

Questions and answers

1. How far does a phone's signal travel through the air?
   • To a satellite
   • As far as the nearest cell tower (answer)
   • All the way to the server
2. What does ICANN do?
   • Controls what is on the internet
   • Stops spam
   • Coordinates domain names and IP addresses (answer)
3. What can happen to the packets of one message?
   • They always take one path
   • They can travel along different paths to the same place (answer)
   • They are sent as one piece
4. How wide is a cable most of the way across an ocean?
   • About as wide as a garden hose (answer)
   • About as wide as a road
   • About as wide as a pencil case
5. Why do countries need more than one cable?
   • So they can sell more cables
   • So sharks cannot bite
   • So connections keep working if one is damaged (answer)

Words

• browser: page-getting program
• ICANN: names coordinator
• switch: forwards messages locally
• packets: small pieces