[Sidrops] Re: Mike Bishop's No Objection on draft-ietf-sidrops-manifest-numbers-08: (with COMMENT)

[Tom Harrison <[e-mail]>]

Hi Mike,

Thanks for your review.

On Wed, Aug 20, 2025 at 01:21:01PM -0700, Mike Bishop via Datatracker wrote:
> With regard to the SHOULD NOT change filenames, I will note that one
> common versioning approach in some areas is to give every version a
> unique filename which will never change (immutable), such that all
> prior versions can be retrieved if needed. Thus, I can conceive of a
> CA that chooses to change the filename with each new manifest, such
> that the old manifests remain available for comparison purposes. If
> the filename is no longer considered a security mechanism, it's
> unclear that this deployment pattern needs to be discouraged.

On this topic, all known CA implementations use stable filenames for
manifests, and most follow the guidance in
https://www.rfc-editor.org/rfc/rfc6481.html#section-2.2 about using a
value derived from the public key of the CA.  We think that the chance
of there being a CA using an alternative approach is sufficiently low
that it's not necessary to expand on this point in the document.

-Tom