Assignment 2

                   CS594-ipp05  revised: 8/14/05

Assigned: 9/1/05
Due: 6:00pm 9/9/05 

Objective:  tcpdump/ethereal

Points: 15

Use tcpdump or ethereal on your personal machine for the following.

 1. do a ping  from your machine to a distant machine  (bout 3 packets)
    use tcpdump/ethereal to capture and examine the ping packets
   a) what IP fields are changing in packets from your machine?
   b) what ICMP fields are changing
   c) what data is carried in the ping packet
   d) from the packet trace, what is the ethernet address of your machine?
   e) what is the ethernet address of the reply packets?  what machine
           is that?  (maybe use "arp" command)

  2. do a traceroute from your machine to a distant machine (in another domain)
     (e.g. home machine to whisper.cs.utk.edu)
     capture and examine the traceroute packets
   a) what is the typical flow of packets in a traceroute
   b) what is the pattern of the TTL field of packets from your machine

  3.  use tcpdump or ethereal to read  ~dunigan/ipp05/what.dmp
   a) what are the IP addresses (dotted decimal) of two hosts?
   b) what is RTT between hosts?
   c) what protocol is being used?
   d) comment on IP flag bits in the packets.
   e) what is ether address of host sending the first packet?
   f) what is IP ID sequence (hex) for the packets from each host?
   g) in the 2nd packet, assume the initial ttl of the packet was (255,
            hex ff), how many hops away is this host?

  4. on one of the CS lab linux boxes (e.g. cetus1) do /sbin/ifconfig eth0
     a) what is ether address of the machine?
     b) what is broadcast address and   mask?
     c) what is  IP address? 
     d) what is global inet6 address? 
     e) what is value MTU ?
     f) what is value of txqueuelen?  (any idea what this affects?)
     g) any collisions or errors?

   5. Parse the following hex dump of an ip packet 
       4500 003c 93da 4000 4006 238a c0a8 0104 c0a8 0103
       a) what is IP version?
       b) what is IHL? 
       c) what is checksum (hex)?
       d) what is total packet length (decimal)?
       e) what is TTL? 
       f) what is ID (hex)?
       g) what is protocol? (decimal value and name)
       h) what are source and destination addresses (dotted decimal)

email your answers to dunigan@cs.utk.edu, with a subject of "ipp05 assignment 2"