utilities for listing users and communicating with them
utilities for manipulating remote files
utilities for obtaining remote login shells and executing remote commands
the history of the Internet
protocols used on the Internet
applications that access the Internet
the Domain Name Service used on the Internet
the World Wide Web, web browsing, and web searching
Quiz
1.
What's the difference between a bridge, a router, and a gateway?
2.
What's a good way for a system administrator of a multi-user system to tell people about important events?
3.
Why is ftp more powerful than rcp?
4.
Why is rcp easier to use than ftp?
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5.
Describe some uses of common ports.
6.
What does machine equivalence mean and how can you make use of it?
7.
Why does the NIC allocate very few Class A addresses?
8.
What is the difference between the http and https protocols?
9.
If you were looking for Sun Microsystems' web page, what address would you try first?
10.
What are the two most significant differences between the TCP and UDP protocols?
Exercises
1.
Try out rcp and rsh as follows:
copy a single file from your local host to a remote host by using rcp
obtain a shell on the remote host using rsh and edit the file that you just copied
exit the remote shell using exit
copy the file from the remote host back to the local host using rcp
[level: easy]
2.
Use telnet to obtain the time of day at several remote host sites. Are the times accurate relative to each other? [level: medium]
3.
Connect to the www.internic.net web site and explore it to find out what kinds of services the NIC provides. Look up information about your domain name (or your ISP's domain name). [level: medium]
Projects
1.
Write a shell script that operates in the background on two machines and ensures that the contents of a named directory on one machine is always a mirror image of another named directory on the other machine. [level: hard]
2.
Pretend you want to buy the latest CD of your favorite group but you don't know of an Internet site that sells them (there are many). Do a web search with several keywords (like music, CD, purchase, and the name of the group). See if you find a way to buy the CD. Explore some of the unwanted 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]
