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Re: [TLS] Pre_shared_key Extension Question

Eric Rescorla <ekr@rtfm.com> Thu, 18 August 2016 15:30 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Thu, 18 Aug 2016 08:29:31 -0700
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To: Benjamin Kaduk <bkaduk@akamai.com>
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Cc: "<tls@ietf.org>" <tls@ietf.org>
Subject: Re: [TLS] Pre_shared_key Extension Question
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On Thu, Aug 18, 2016 at 8:18 AM, Benjamin Kaduk <bkaduk@akamai.com> wrote:

> On 08/17/2016 05:17 PM, Eric Rescorla wrote:
>
> It would be a fairly significant simplification to say you could only have
> one PSK, because then we could easily require the client to prove knowledge
> of the key, for instance by stuffing a MAC at the end of the ClientHello as
> we discussed in Berlin.
>
> So:
> Is there any demand for multiple identities? I do not believe there is any
> in the Web context. If not, we should remove this feature.
>
>
> Then at PSK rollover time, clients are expected to fall back to a new TLS
> connection using the other PSK?
>

I'm not sure I follow. Can you say more?

-Ekr




> -Ben
>

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