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Re: [tcpm] SYN in SYN_RCVD state

"Vishal Study" <vishal.study@gmail.com> Sun, 21 October 2007 11:26 UTC

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Date: Sun, 21 Oct 2007 04:25:25 -0700
From: Vishal Study <vishal.study@gmail.com>
To: Marco Mellia <mellia@tlc.polito.it>
Subject: Re: [tcpm] SYN in SYN_RCVD state
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But RFC 793, pg 71 seem to say that the server should send out a RST
if SYN is rx in SYN-RCVD state (assuming SYN seq number is within the
window, which is true in the example I had mentioned).

Any thoughts on this?

Thanks!

On 10/20/07, Marco Mellia <mellia@tlc.polito.it> wrote:
> Vishal Study ha scritto:
> > Consider the following scenario:
> >
> > 1. TCP client sends SYN to server; server goes to SYN_SENT state
> >
> > 2. server responds with SYN+ACK;  server goes to SYN_RCVD state
> > but SYN+ACK sent to client is lost somewhere in the network.
> >
> > 3. client re-sends SYN on its timeout (couple of seconds later) to server
> >
> > What should be the server behavior? Should it retransmit SYN+ACK or
> > should it send a RST?
> >
> >
> Clearly the first case!
> Marco
>


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