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Re: [TLS] Record header size?

Daniel Kahn Gillmor <dkg@fifthhorseman.net> Tue, 17 November 2015 20:46 UTC

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From: Daniel Kahn Gillmor <dkg@fifthhorseman.net>
To: Eric Rescorla <ekr@rtfm.com>, "Short, Todd" <tshort@akamai.com>
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Date: Tue, 17 Nov 2015 15:45:53 -0500
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Subject: Re: [TLS] Record header size?
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On Tue 2015-11-17 12:09:30 -0500, Eric Rescorla wrote:
> The concern here is backward compatibility with inspection middleboxes which
> expect the length field to be in a particular place. We agreed in Seattle to
> wait for early deployment experience before modifying the header to move
> the length.

In particular, if we're going to make a change to the TLS record header,
the change would be to remove the version and the type entirely, leaving
only two octets of length on each record.  Is a two-octet offset going
to be problematic?

         --dkg

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