Re: [TLS] TLS Charter Revision

Eric Rescorla <> Fri, 13 December 2013 01:24 UTC

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From: Eric Rescorla <>
Date: Fri, 13 Dec 2013 09:23:49 +0800
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To: "Salz, Rich" <>
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Subject: Re: [TLS] TLS Charter Revision
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On Thu, Dec 12, 2013 at 11:22 PM, Salz, Rich <> wrote:
> I agree with Marsh that PFS should be included.

Can you elaborate more on this? TLS already supports PFS, so are you
arguing we should maintain that support or that we should strip out
all non-PFS cipher suites (see the thread on static RSA...)

> I am concerned about the 'political' emphasis on reducing round trips. One of the arguments heard I hear against 'https everywhere' is that the extra round-trips' cause too much latency and impact customer's web experience. If we can work to reduce RTT without sacrificing security, then that's great and I would like to see "while maintaining security features" or some such added.

I have no problem with that. I would have thought it went without saying
but I'm more than happy to have us say it.

> I would like to add a bullet that says backward compatibility with previous  versions is not a requirement. Given all that downgrade fallback issues that continually arise here, we should strongly consider if the right thing to do is just break the chain.

I think this is actually backwards: it's precisely having some sort of secure
backward negotiation that allows for clean deployment. The problem is
that people have screwed up those mechanisms. If we just do a clean
break there is no chance that secure version detection will work.


>         /r$
> --
> Principal Security Engineer
> Akamai Technology
> Cambridge, MA
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