Packet dissection

A packet

0000  00 00 50 43 c2 32 00 1f  5b c0 70 ce 08 00 45 00   ..PC.2.. [.p...E.
0010  00 30 3e a4 00 00 40 11  0d f8 0a dd 12 e9 0a dd   .0>...@. ........
0020  05 7f f5 9b 00 45 00 1c  ce 3b 00 01 66 69 6c 65   .....E.. .;..file
0030  2e 74 78 74 00 6e 65 74  61 73 63 69 69 00         .txt.net ascii.  

Packet dissection

Datalink layer: Ethernet
00 00 50 43 c2 32 00 1f 5b c0 70 ce 08 00

destination ethernet address, source ethernet address, type of payload, IP

Network layer: IP
45 00 00 30 3e a4 00 00 40 11 0d f8 0a dd 12 e9 0a dd 05 7f

version number (4 bits), header length (4 bits), TOS packet length identification flags (4 bits) and fragments TTL protocol (next) checksum source address destination address

Transport layer: UDP
f5 9b 00 45 00 1c ce 3b

source port destination port length checksum

Appication layers: TFTP
00 01 66 69 6c 65 2e 74 78 74 00 6e 65 74 61 73 63 69 69 00

operation (read request) file name format