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[Ssh] Re: Deprecation of Compression - Scope

Damien Miller <djm@mindrot.org> Tue, 13 October 2026 04:22 UTC

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Date: Tue, 13 Oct 2026 15:22:23 +1100
From: Damien Miller <djm@mindrot.org>
To: "Salz, Rich" <rsalz@akamai.com>
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Subject: [Ssh] Re: Deprecation of Compression - Scope
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On Mon, 12 Oct 2026, Salz, Rich via Ssh wrote:

> On 10/12/26, 4:59 PM, "Simon Josefsson via Ssh" <ssh@ietf.org> wrote:
>  *  Compression has more or less disappeared from TLS for somewhat similar
>  *  reasons, therefor I would lean towards the same conclusion for SSH.
>  *  Futher, option (2) allows implementer to remove more code, which reduces
>  *  overall complexity.
> 
> I agree, for the same reasons.

I also agree. I don't think transport layer compression can ever be
made simultaneously safe and effective and I support its deprecation.

AFAIK safer compression can be effectively added at the application
layer or with wrapper tools (for forwardings, etc).

I did do some prototyping towards channel-layer compression in SSH and
decided that it's not trivial.

-d

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