Re: TCP sequence numbers

[Bob Braden <[e-mail]>]

  *> From [e-mail] Tue Sep 19 06:38:47 2000
  *> Date: Tue, 19 Sep 2000 17:56:41 +0530
  *> From: "T Srivathsa" <[e-mail]>
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  *> Subject: TCP sequence numbers
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  *> Hi,
  *> 
  *>     My understanding of the Initial Sequence Numbers in TCP is that they
  *> increment at a much faster rate (typically once every 4 usecs) than the
  *> subsequent sequence numbers (which depends on how fast TCP pumps that
  *> connection's data into the network).
  *> 

Please see the Appendix to RFC1185.

Bob Braden

  *>  This way, during a reincarnation (same src, dst ip addresses and same
  *> src, dst ports) of a connection, even if an old duplicate surfaces, it
  *> can be rejected because "it's sequence number will be WAY BEHIND".
  *> 
  *> Question 1:
  *>     Recently, there has been talk on the tcp-impl mailing list that ISN
  *> can be random. If so, how can it be guaranteed that an old duplicate
  *> will be rejected during a reincarnation?
  *> 
  *> Question 2:
  *>     Can circumstances arise such that TCP pumps the connection's data
  *> into the network at such a high rate, that subsequent sequence numbers
  *> increase at the same rate as ISNs?
  *>     For eg, an FTP between very fast machines, on a very fast LAN, with
  *> TCP WINDOW SCALING?
  *> 
  *> 
  *> Bye
  *> Srivathsa
  *>