Code change:
interaction models in general, the following set of prerequisites MUST be in place to support the implementation of interaction models: <del> A statement about a distinguishable Attester made by an Endorser without accompanying evidence about its validity, used as proof of identity. </del> <ins> An Authentication Secret MUST be available exclusively to an Attesting Environment of an Attester. The Attester MUST protect Claims with that Authentication Secret, thereby proving the authenticity of the Claims included in Evidence.  The Authentication Secret MUST be established before RATS can take place. A statement about a distinguishable Attester made by an Endorser. </ins> The provenance of Evidence with respect to a distinguishable Attesting Environment MUST be correct and unambiguous. <del> An Attester Identity MAY be a unique identity, MAY be included in a zero-knowledge proof (ZKP), MAY be part of a group signature, or it MAY be a randomized DAA credential DAA. </del> <ins> An Attester Identity MAY be an Authentication Secret which is available exclusively to one of the Attesting Environments of an Attester.  It MAY be a unique identity, MAY be included in a zero- knowledge proof (ZKP), MAY be part of a group signature, or it MAY be a randomized DAA credential DAA. </ins> Attestation Evidence MUST be authentic. In order to provide proofs of authenticity, Attestation Evidence SHOULD be cryptographically associated with an identity document <del> (e.g. an PKIX certificate or trusted key material, or a randomized DAA credential DAA), or SHOULD include a correct and unambiguous and stable reference to an accessible identity document. An Authentication Secret MUST be available exclusively to an Attester's Attesting Environment. The Attester MUST protect Claims with that Authentication Secret, thereby proving the authenticity of the Claims included in Evidence.  The Authentication Secret MUST be established before RATS can take place. </del> <ins> (e.g., a PKIX certificate or trusted key material, or a randomized DAA credential DAA), or SHOULD include a correct, unambiguous and stable reference to an accessible identity document. </ins> Evidence MUST include an indicator about its freshness that can be understood by a Verifier.  Analogously, interaction models MUST

Related discussion:
text: DAA doesn't introduce a new information elements, and only augments the scope/definition of Attester Identity and Authentication Secret IDs, describing it after the introduction of all the 3 basic interaction models would be better. Putting DAA in the middle makes me feel the basic interaction models rely upon DAA, but actually it's not. This document extends the duties of the Endorser role as defined by the RATS architecture with respect to the provision of these Attester Identity documents to Attesters. The existing duties of the Endorser role and the duties of a DAA Issuer are quite similar as illustrated in the following subsections. Comment > Without DAA, I think the Endorser also needs to provision the Attester Identity to Attesters. And as I understand, the DAA Issuer is a supply chain entity before the Attester being shipped, so it is the Endorser when DAA is used, right? If yes, then in the next sentence, the comparison between Endorser and DAA Issuer doesn't make sense to me. Section 5.1 Endorsers Comment > Does this section have difference with the definition of Endorser in architecture draft? If not, is it necessary to keep this section? Comment > This section only describes the Layered Attestation, but the scope of Endorsement is more than what's described here. Endorsement indicates the Attester's various capabilities such as Claims collection and Evidence signing. For other situations than Layered Attestation, the Endorser and Endorsement are also needed. So why only mention Layered Attestation here? I don't see any special relationship between DAA and Layered Attestation. Section 5.2 Endorsers for Direct Anonymous Attestation In order to enable the use of DAA, an Endorser role takes on the duties of a DAA Issuer in addition to its already defined duties. DAA Issuers offer zero-knowledge proofs based on public key certificates used for a group of Attesters [DAA]. Effectively, these certificates share the semantics of Endorsements, with the following exceptions: Comment > In the first sentence, I suggest saying that "a DAA Issuer takes on the role of an Endorser".