[Seat] Use-cases rewrite

[Ionut Mihalcea <[e-mail]>]

Hi all,

As previously promised, I have now opened a new PR against the use-cases draft [0], shaping the use-case definitions into a template, as described in my previous email [1].

For those interested in the full text, you can find that under section 5 here [2]. It's worth noting that this text attempts to include the previous deployment examples collected from industry as examples for the new templates. The industry use-cases described in the open PRs (left over from before adoption) have also been included.

The revised Use Cases section organizes SEAT deployments around two base attestation directions: server-as-Attester, where a client obtains assurance before releasing data or performing a sensitive operation, and client-as-Attester, where a service obtains assurance before admission or release of a protected asset. It also defines common behaviour across profiles, including the respective responsibilities of the Verifier and Relying Party, fail-closed handling when attestation is required, Attestation Result lifetime and reuse, and the need for fresh assurance following expiry, an identified state change, or invalidation of a connection binding.

Mutual attestation, re-evaluation on long-lived or resumed connections, and intermediary-aware deployment are described as overlays on those base directions rather than independent attestation models. These overlays preserve independent Evidence, Verifiers, trust anchors, policies, lifetimes, and authorization decisions unless a deployment explicitly coordinates them. The section includes examples covering confidential workloads and secret provisioning, network admission, high-assurance operations, multi-party computation, workload migration, runtime re-attestation, AI governance, TLS intermediaries, and service meshes.

This PR will be open for a while to allow reviews, feedback, and suggestions to arrive.

IMPORTANT NOTE: as previously with the attacker model, this PR addresses the use-cases section ONLY. It will be followed up by a similar PR reorganising the properties defined in the draft. Other clarifications or changes should be done in separate PRs.

Thank you,
Ionut


[0] https://github.com/ietf-wg-seat/draft-ietf-seat-use-cases/pull/61

[1] https://mailarchive.ietf.org/arch/msg/seat/5iQlAOciB2deQ6FukrLwoeX7zvk/

[2] https://raw.githubusercontent.com/ietf-wg-seat/draft-ietf-seat-use-cases/refs/heads/use-cases-refit/draft-ietf-seat-use-cases.txt