Re: [TLS] Multiple records in record limit (was: Secdir review)

Eric Rescorla <ekr@rtfm.com> Mon, 26 February 2018 02:13 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Sun, 25 Feb 2018 18:12:32 -0800
Message-ID: <CABcZeBNxU3GTeek7V50W_Cbva=zAQwgRaL=VQAjSGDegTT1QFA@mail.gmail.com>
To: Martin Thomson <martin.thomson@gmail.com>
Cc: "<tls@ietf.org>" <tls@ietf.org>, Benjamin Kaduk <kaduk@mit.edu>, Alan DeKok <aland@deployingradius.com>
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Subject: Re: [TLS] Multiple records in record limit (was: Secdir review)
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I think this is the right answer.

-Ekr


On Sun, Feb 25, 2018 at 5:39 PM, Martin Thomson <martin.thomson@gmail.com>
wrote:

> Out of the secdir review (thanks again Alan!), I realized that the
> draft never actually said this:
>
>    PMTU governs the size of UDP datagrams, which limits the size of
> records, but
>    does not prevent records from being smaller.  An endpoint that sends
> small
>    records is still able to send multiple records in a single UDP datagram.
>
> I think that I should add that explanation.
>
> Does anyone think that this should go further and advise against
> putting multiple records in the same datagram?
>
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