TCP flags usage

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bravobritto
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TCP flags usage

Post by bravobritto »

I don't know wether this topic make sense in this class of forum. Can anyone explain what you mean by TCP flags ? What is SYN, FIN, etc. ? How the firewall reacts to such TCP flags ? I'm using a hardware firewall NSF 6416. This firewall is loaded with Linux based OS. I ran fwmonitor to view TCP flags.

Regards
Britto :o
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RobertGonzalez
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Post by RobertGonzalez »

Moved to Miscellaneous.
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volka
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Post by volka »

each tcp/ip packet has a header and there's space for some flags - fields that can either be "flagged" or not (i.e. containing 1 or 0).
Two of these flags are called SYN and FIN - and there's another one called ACK.
You can find an example of what they are used for at http://www.knowplace.org/pages/howtos/f ... erview.php
You might also find http://www.knowplace.org/pages/howtos/f ... tables.php interesting.
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