Re: [TLS] PR#28: Converting cTLS to QUIC-style varints

Nick Harper <nharper@google.com> Wed, 07 October 2020 00:33 UTC

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From: Nick Harper <nharper@google.com>
Date: Tue, 6 Oct 2020 17:33:32 -0700
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To: Eric Rescorla <ekr@rtfm.com>
Cc: Marten Seemann <martenseemann@gmail.com>, "<tls@ietf.org>" <tls@ietf.org>
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Subject: Re: [TLS] PR#28: Converting cTLS to QUIC-style varints
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I have no strong opinion on how this is formatted. I'd base my decision on
what the maximum value cTLS needs to encode: If 2^22-1 is sufficient, let's
keep it as is, otherwise let's change it to the QUIC format (or some other
change to increase the max value). I do like that the existing scheme,
compared to QUIC varints, is more efficient for values 64-127 and just as
efficient for the rest.

On Mon, Oct 5, 2020 at 8:09 PM Eric Rescorla <ekr@rtfm.com> wrote:

> I don't have a strong opinion on whether to require a minimal encoding,
> but if we're not going to use QUIC's encoding as-is, then I would rather
> stick with the existing scheme, which has twice as large a range for the 1
> byte encoding and is thus more compact for a range of common cases.
>
> -Ekr
>
>
> On Mon, Oct 5, 2020 at 7:31 PM Marten Seemann <martenseemann@gmail.com>
> wrote:
>
>> In that case, why use QUIC's encoding at all? It would just put the
>> burden on the receiver to check that the minimal encoding was used.
>> Would it instead make more sense to modify QUIC's encoding, such that the
>> 2-byte encoding doesn't encode the numbers from 0 to 16383, but the numbers
>> from 64 to (16383 + 64), and equivalently for 4 and 8-byte encodings?
>>
>> On Tue, Oct 6, 2020 at 9:22 AM Salz, Rich <rsalz@akamai.com> wrote:
>>
>>> Can you just say “QUIC rules but use the minimum possible length”?
>>>
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