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Re: [TLS] Should we require compressed points

Martin Thomson <martin.thomson@gmail.com> Wed, 22 October 2014 18:47 UTC

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Date: Wed, 22 Oct 2014 11:47:08 -0700
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From: Martin Thomson <martin.thomson@gmail.com>
To: Eric Rescorla <ekr@rtfm.com>
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Subject: Re: [TLS] Should we require compressed points
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On 22 October 2014 11:26, Eric Rescorla <ekr@rtfm.com> wrote:
>> What are the reasons for getting rid of uncompressed points?
>
>
> Really what I want is to get rid of point negotiation, because it's yet
> another
> point of complexity and it's not universally implemented anyway. Given that
> people seem to think that compressed points are better, I figured that was
> the way to go. If people prefer to just require uncompressed points (at
> least for the existing X9.63 curves) I could certainly live with that.

Yep, and I'll note that 32 octets isn't a trivial amount of space in a
handshake.  We're particularly space constrained here.  If that's 32
octets more of application data I'd have available, I suspect that
another compressed HTTP/2 request - or a good proportion of one -
could fit in that space (for a 0 RTT mode in particular).

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