Re: [openpgp] AEAD Chunk Size

"brian m. carlson" <> Sat, 30 March 2019 00:19 UTC

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Date: Sat, 30 Mar 2019 00:19:49 +0000
From: "brian m. carlson" <>
To: Jon Callas <>
Cc: "Neal H. Walfield" <>,, Justus Winter <>, Jon Callas <>
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Subject: Re: [openpgp] AEAD Chunk Size
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On Thu, Mar 28, 2019 at 07:19:39PM -0700, Jon Callas wrote:
> I wrote a point-by-point reply and decided that that’s not productive. I’m going to try to cut to the chase on this, so forgive me if I have dodged an important point. I’m happy to come back to it later.
> Like some interim replies, particularly Bart Butler, I thought we had a rough consensus and that it was approximately:
> * MUST support 16KB chunks.
> * SHOULD support 256K chunks, as these are common (Protonmail).
> * MAY support larger up to the present very large size.
> * MAY reject or error out on chunks larger than 16KB, but repeating ourselves, SHOULD support 256K.

I think this is fine. It covers what's requires for interoperability, it
makes prudent suggestions, and it allows people leeway if they know
they're the only one consuming their data.

If people like my original proposal, that's also fine with me (as would
be expected).
brian m. carlson: Houston, Texas, US