Subject: Re: Simultaneous Open - Reg

From: Bob Braden <[email-masked]>
Date: Mon, 22 Apr 2002 17:53:06 GMT

*> From [email-masked]  Sun Apr 21 22:07:54 2002
  *> From: "Udaya kumar" <[email-masked]>
  *> To: <[email-masked]>
  *> Subject: Simultaneous Open - Reg
  *> Date: Mon, 22 Apr 2002 10:13:26 +0530
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  *> Hi
  *> 
  *>     I have a query regarding simultaneous open in TCP.
  *> 
  *>     The response to a SYN segment in the SYN_SENT state is to send a SYN,ACK carrying the old sequence number(i.e seq. no of the SYN segment sent earlier). Ref -> rfc793 &&  rfc1122. If the response is such,  then the SYN,ACK segment would be dropped at the receving side due to sequence number check. Hence connection cannot be established.

No.  It will be accepted and the "receiving" side will go from SYN_SENT
state to ESTABLISHED.

Bob Braden