Re: [TLS] AES-OCB in TLS [New Version Notification for draft-zauner-tls-aes-ocb-03.txt]

Jeffrey Walton <noloader@gmail.com> Mon, 01 June 2015 16:05 UTC

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Date: Mon, 1 Jun 2015 11:53:47 -0400
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From: Jeffrey Walton <noloader@gmail.com>
To: Aaron Zauner <azet@azet.org>
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Subject: Re: [TLS] AES-OCB in TLS [New Version Notification for draft-zauner-tls-aes-ocb-03.txt]
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On Mon, Jun 1, 2015 at 9:05 AM, Aaron Zauner <azet@azet.org> wrote:
> ...
> Ok. I won't touch ECDSA in my document for the time being.
>
> The PSK cipher-suites still bother me. I'm not sure I want to support
> them. While RFC6655 (CCM) specifies PSK cipher-suites, RFC5288 (GCM)
> does not. These are currently included in my draft because Nikos and
> Peter Gutmann suggested including them.
>
What do you suggest for resource constrained devices? What are the
remaining choices?

When the device cannot do public key, they often use PSK.

PSK also has two desirable properties: channel binding and mutual
authentication, and most other cipher suites don't provide them.

Jeff