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Re: [MLS] Substitute AES-128-GCM with AES-256-GCM for TreeKEM

"Salz, Rich" <rsalz@akamai.com> Thu, 20 September 2018 11:55 UTC

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From: "Salz, Rich" <rsalz@akamai.com>
To: Raphael Robert <raphael@wire.com>, "mls@ietf.org" <mls@ietf.org>
Thread-Topic: [MLS] Substitute AES-128-GCM with AES-256-GCM for TreeKEM
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Date: Thu, 20 Sep 2018 11:55:37 +0000
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Archived-At: <https://mailarchive.ietf.org/arch/msg/mls/Iumw5s4ZtlAIPM31PHgnuwv2gL8>
Subject: Re: [MLS] Substitute AES-128-GCM with AES-256-GCM for TreeKEM
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Is there a good rationale, perhaps a link, explaining why all parts of a cipher-suite need to be at the same strength? I tend to call those things “crypto numerology” but perhaps (not being a cryptographer) I’m just biased.  Yes, I understand that it might be no better than the weakest link.

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