Re: [tcpm] TCP Long Options

Joe Touch <touch@ISI.EDU> Mon, 07 July 2008 21:53 UTC

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Date: Mon, 07 Jul 2008 14:52:09 -0700
From: Joe Touch <touch@ISI.EDU>
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Subject: Re: [tcpm] TCP Long Options
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Adam Langley wrote:
> On Mon, Jul 7, 2008 at 2:07 PM, Joe Touch <touch@isi.edu> wrote:
>> I'm recalling that no mechanism was ever developed that was backward
>> compatible with legacy TCP implementations, i.e., that "did the right thing"
>> for SYNs with long options. Doing well for other segments is somewhat moot
>> if SYNs cannot be extended, because space is most critical for them.
> 
> I don't believe that such a system is actually possible...

I believe that was the sticking point the last time we talked. If we 
give up on backward compatibility, the variants become overwhelming, 
including Mark Allman's "let's double all the fields" proposal, as I 
recall, and none is sufficiently motivated at this time AFAICT. I.e., it 
is when we give up on backward compatibility that Braden's observation, 
I believe, applies.

Joe

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