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Re: [TLS] RFC 6066 - Max fragment length negotiation

Martin Thomson <martin.thomson@gmail.com> Fri, 17 March 2017 06:24 UTC

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From: Martin Thomson <martin.thomson@gmail.com>
Date: Fri, 17 Mar 2017 17:24:09 +1100
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To: Peter Gutmann <pgut001@cs.auckland.ac.nz>
Cc: Nitin Shrivastav <nitin.shrivastav@broadcom.com>, "tls@ietf.org" <tls@ietf.org>
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Subject: Re: [TLS] RFC 6066 - Max fragment length negotiation
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On 17 March 2017 at 14:49, Martin Thomson <martin.thomson@gmail.com> wrote:
> The design I would use is much simpler.  The extension would carry a
> two octet value that is the maximum size of the plaintext that the
> endpoint is willing to receive.  A client could say 2^14 and that
> would allow the server to send that much if it were able.  The same
> server could say 5 and the client would be forced to fragment like
> crazy (ok, that last might be too far, we'd probably want to set a
> lower bound on the value).
>
> I'd happily implement and advertise that extension.

I'd even go so far as to specify it:

https://martinthomson.github.io/tls-record-limit/

I'll submit an I-D once the blackout ends if people are interested in this.

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