Re: [quicwg/base-drafts] Include epoch in the AAD or the nonce? (#3661)

Martin Thomson <> Tue, 19 May 2020 01:26 UTC

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Date: Mon, 18 May 2020 18:26:30 -0700
From: Martin Thomson <>
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Subject: Re: [quicwg/base-drafts] Include epoch in the AAD or the nonce? (#3661)
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Given the limits we have on usage, 2^32 would mean exhausting epochs before we exhaust packet numbers.  Both are pretty large values, and maybe we can avoid that limit for some future AEAD.  For AES, that means 2^56.5, which equates to roughly 1e20 bytes (100 exabytes) at a 1400 byte MTU, which seems like it would be tolerable.

That said, this is a fairly fundamental change with fairly thin rationale.  If people don't want to do this, then I'm not inclined to push very hard for a change.

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