This is the first lab assignment. The assignment requires that you use some of the UNIX-based network tools available. The tools you will be using include:

1. arp
2. traceroute
3. netstat
4. nslookup
5. whois

All of these tools should be available for any version of Solaris. You want to make extensive use of the man pages for each. If you have problems running any of these commands or accessing the WWW pages, please let me know as soon as possible.

• arp
• What is the arp table for your local machine. Include a printout.

 
• What is the option to manually add entries to the arp table? Create a hypothetical new table entry. What would the command look like to add this entry? What happens when you try to add an entry to the arp table? Why do you suppose you get the result that you do?

 
• Determine a mechanism, by whatever ``legal'' means possible to have additional host entries appear in the arp table. Use this mechanism to add at least one new host to the arp table and include a printout that is different from Part (A).

 
• By any legal means, can you add an entry to arp table for any host you want? If yes, how; if no, why?

 
• Arp cache entries obviously timeout after some amount of time. How could you figure out what the timeout value actually is? (Anyone care to figure out what the actual value is?)

 

 
 
 

• traceroute
• Explain in detail how traceroute works.

 
• Perform a traceroute from your machine to ftp.ietf.org. Include a copy of the output and explain what happened including a description of what each of the fields means.

 
• What happens if you traceroute to a non-existent machine? Include a copy of the traceroute. How do you know the machine that you traced to was non-existent instead of just down or not responding? If you traceroute to another non-existent machine, how are the results similar/different?

 

 
 
 

• netstat
• What is netstat and what is it used for?

 
• How is netstat -p different from arp -a?

 
• What parameters should you use to show all the TCP connections established? Include a printout of this list.

 
• What does netstat -r show? What is noteworthy about the output?

 
• netstat can be used to display network interface status. What option of netstat does that? By using netstat, figure out the number of interfaces on your machine.  In the output you will find an interface named lo0 as a loopback interface. Can you say anything about this interface, about its function?

 

 
 
 

• nslookup
• What is the IP address for the machine lennon.cc.gatech.edu?

 
• What local machine is this information coming from? Why is it coming from this machine?

 
• Here is the problem: I want to find the IP address of where my email to friend@aol.com goes. What happens when I do an nslookup of aol.com?

 
• What you really need to do is find the ``mail exchanger'' for aol.com. There is an option in nslookup that tells you what the mail exchanger is for aol.com. Figure out the exact syntax of the format of this command, and execute it. Now what is the IP address of where my email to friend@aol.com goes?

 

 
 
 

• whois
HINT: You will need to use a different server than the default whois server. One to try is: whois.arin.net.
• What class of IP address is my machine (jackson.cs.ucsb.edu)? What subnet does my address belong to? Who is the coordinator for this network?

 
• Who is the coordinator for the network that morticia.cc.gatech.edu is on?

 
• Who is the coordinator for the e-mail network at Microsoft, and what is his e-mail address? Include information about the steps you took and the results of the queries you made to figure out this information.

 
• Ever send mail to president@whitehouse.gov? Tell me something about the White House e-mail network? Also, how is the network address for this particular network different from the other networks?