Homework 5
Due Tuesday, December 2

Directions for submission: Place your C source code and makefile, and a README file reporting your findings, in a .tar.gz.uu file.

Write a program to input the Ethernet records in

   ~matloff/Pub/PktTrc01.dat

The program will determine the following:

• average received length of all Ethernet frames

• the total number of Ethernet frames in the data set

• the total number of TCP frames

• the total number of UDP frames

• the most frequently-appearing Ethernet destination address

• the number of ftp control frames (destination port 21, TCP)

• IP addresses (xxx.xxx.xxx.xxx format) and host names (use gethostbyaddr() for the latter) for source and destination in the first TCP frame, plus source and destination Ethernet board numbers (in hex) for that frame (note to yourself which machines we are talking about!)

The relevant header formats are shown on pages 123, 221 and 291 of Peterson and Davie. Note that the Type code in an Ethernet frame for IP is 0x0800.

Read the data documentation starting. Make sure to browse through the data file (using the Unix od command) "by hand" a bit first to get a feeling for the layout of the data, checking to see, for example, that there is always an 0x0800 code where it ought to be in the first two or three frames.