Your lab final is really simple. Your task is to go through one of the following pairs of tcpdump outputs (which includes the IP header and the transport level header but not the Ethernet header), determine where the server is running (IP address and port), whether it is running TCP or UDP, and what application level message you need to send to it to receive the corresponding output. Once you have identified the server, write a simple client program that sends the correct request to the server, receives the response, prints out the response, closes the socket, and exits.
The program doesn't need to be too fancy - you can hard-code the pertinent information (like the server's address and port number). You are free to use any resources; you will have access to the Web, all of your past programs and labs, and any of the class notes.
Once you are done, use script to capture a run of your program that demonstrates that you successfully communicate with the server and retrieve the correct response. Turn in your source code for the client and this script output. Just print them out and give them to Anthony.
If you are in the Thursday lab section and your student ID number is even, use the following tcpdump data:
Request:
0x0000: 4500 0038 5c27 4000 4006 1d67 995a c72f E..8\'@.@..g.Z./
0x0010: 995a c74d 9c43 9470 6b32 7865 de52 a631 .Z.M.C.pk2xe.R.1
0x0020: 8018 16d0 dbd9 0000 0101 080a 0158 10bd .............X..
0x0030: 0371 abd2 1234 5678 .q...4Vx
Response:
0x0000: 4500 0038 0de5 4000 4006 6ba9 995a c74d E..8..@.@.k..Z.M
0x0010: 995a c72f 9470 9c43 de52 a631 6b32 7869 .Z./.p.C.R.1k2xi
0x0020: 8018 05a8 c15c 0000 0101 080a 0371 abd3 .....\.......q..
0x0030: 0158 10bd 8765 4321 .X...eC!
If you are in the Thursday lab section and your student ID number is odd, use the following tcpdump data:
Request:
0x0000: 4500 004c 00ae 4000 4011 78c1 995a c72f E..L..@.@.x..Z./
0x0010: 995a c74d 9c42 9088 0038 3d3c 5768 6f20 .Z.M.B...8=<Who.
0x0020: 6b6e 6f77 7320 7768 6174 2065 7669 6c20 knows.what.evil.
0x0030: 6c75 726b 7320 696e 2074 6865 2068 6561 lurks.in.the.hea
0x0040: 7274 7320 6f66 206d 656e 3f00 rts.of.men?.
Response:
0x0000: 4500 002d 0001 4000 4011 798d 995a c74d E..-..@.@.y..Z.M
0x0010: 995a c72f 9088 9c42 0019 c15c 5468 6520 .Z./...B...\The.
0x0020: 5368 6164 6f77 206b 6e6f 7773 00 Shadow.knows.
Good luck!