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Can anyone explain this tcpdump question?

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Special Forums IP Networking Can anyone explain this tcpdump question?
# 1  
Old 08-24-2011
Can anyone explain this tcpdump question?
Please look at the third line that the windows size is 257, but in the fourth line it sends 992 bytes. Can anyone tell me why?

Thanks in advance!!!

Image
# 2  
Old 08-24-2011
Where are you seeing 992 bytes? [edit] I think you mean fourth line.

As I understand it, the window size doesn't fragment individual packets, that's what MTU's for... 992 bytes is small enough to fit in one packet, so...
# 3  
Old 08-24-2011
Window scaling. Look at the opening tcp handshake for the wscale options. You then have to multiply the window sizes by 2^n where n is the wscale value.

Regards,
Alister
This User Gave Thanks to alister For This Post:
cateran
# 4  
Old 08-26-2011
Quote:
Originally Posted by alister
Window scaling. Look at the opening tcp handshake for the wscale options. You then have to multiply the window sizes by 2^n where n is the wscale value.

Regards,
Alister
Brillant!!!!!

How come I forget that Smilie
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