tcpdump question

Olivier Nicole on at cs.ait.ac.th
Fri Aug 29 09:32:39 UTC 2008


Edward,

> I want to know what's meaning of 'S','.','P','F'? 

You should learn a bit about TCP protocol.

S is for SYN (synchronize)
P is for PUSH
F is for FIN
. is for nothing

Pakets are:

3 way hand shake initiate TCP connection
client > server SYN
sever > client SYN ACK
client > server ACK

client > server send data
server > client ACK and send data
client > server ACK

tTermination
client > server FIN
server > client ACK
server > cient FIN
client > server ACK

ACk means acknowledge.

Olivier


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