Chapter 10 - The Internet

Quiz

1. Why does the NIC allocate very few Class A addresses?
Class A addresses only use 8 bits for the network number and the organization is free to use the remaining 24 bits as they wish. This uses up a large chunk of the 32-bit address space, so Class A addresses are only assigned to very large organizations.
2. What is the difference between the http and https protocols?
The https protocol is a secure version of http, it uses an encrypted channel to do its work.
3. If you were looking for Sun Microsystemsí web page, what address would you try first?
Most would probably guess http://www.sun.com, and theyíd be correct.
4. What are the two most significant differences between the TCP and UDP protocols?
  • TCP is reliable, UDP is not.
  • TCP creates a connection, UDP does not.

    • Exercises

    10.1 Pick some companies you know, and try to access their web pages with URLs you make up in the form of www.company.com. [level: easy]
    There is no answer here, the activity is the point. High-tech companies tend to be easier to guess than consumer products (and more often have web sites).
    10.2 Connect to the ìwww.internic.netî web site and explore it to find out what kinds of services the NIC provides. Look up information about your domain name (or your ISPís domain name). [level: medium]
    This activity should provide the students with some insight. Network Solutions, the company currently managing the Internet namespace, also has a web site at www.networksolutions.com.

    Project

    Pretend you want to buy the latest CD of your favorite group, but you donít know of an Internet site that sells them. (There are several.) Do a web search with several keywords (e.g., music, CD, purchase, and the name of the group). See if you can find a way to buy the CD and explore some of the other sites that come up to find out why they satisfied your search so that you know how to make a better search next time. [level: medium]
    Finding out why web searches find things you didnít want helps you specify better search criteria in future searches.