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Re: [tcpm] Re: RFC 1323: Timestamps option

Joe Touch <touch@ISI.EDU> Wed, 30 May 2007 17:42 UTC

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Date: Wed, 30 May 2007 10:41:38 -0700
From: Joe Touch <touch@ISI.EDU>
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To: David Borman <david.borman@windriver.com>
Subject: Re: [tcpm] Re: RFC 1323: Timestamps option
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David Borman wrote:
...
>> I'm wondering whether there's a case where you could have started
>> sending new TSvals, and you get a new data ACK (and start calculating
>> RTTs), and then a packet comes in out of order (e.g., duplicated or
>> SACK). Could this corrupt the RTT? Could this ever happen?
> 
> Besides being an ACK for new data, it also has to have a TSecr beyond
> the initial timestamp you sent.  By the time both of those things are
> true, you should be into normal RFC-1323 processing.

So two checks for every incoming packet, not just during 'sync', right?
(just checking; that's not obvious to me from the description)

Thanks, BTW,

Joe

-- 
----------------------------------------
Joe Touch
Sr. Network Engineer, USAF TSAT Space Segment


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