Change:
may be used to limit the exposure of keys in these cases. However, short-lived certificates need to be renewed more frequently <del> than long-lived certificates.  If an external CA is unable to issue a certificate in time to replace a deployed certificate, the server would no longer be able to present a valid certificate to clients. With short-lived certificates, there is a smaller window of time to renew a certificates and therefore a higher risk that an outage at a CA will negatively affect the uptime of the TLS-fronted service. </del> <ins> than long-lived certificates.  If an external Certification Authority (CA) is unable to issue a certificate in time to replace a deployed certificate, the server would no longer be able to present a valid certificate to clients.  With short-lived certificates, there is a smaller window of time to renew a certificates and therefore a higher risk that an outage at a CA will negatively affect the uptime of the TLS-fronted service. </ins> Typically, a (D)TLS server uses a certificate provided by some entity <del> other than the operator of the server (a "Certification Authority" or CA) RFC8446 RFC5280.  This organizational separation makes the (D)TLS server operator dependent on the CA for some aspects of its operations, for example: </del> <ins> other than the operator of the server (a CA) RFC8446 RFC5280.  This organizational separation makes the (D)TLS server operator dependent on the CA for some aspects of its operations, for example: </ins> Whenever the server operator wants to deploy a new certificate, it has to interact with the CA.

Discussion:
Need to address and directorate reviews.
Correction ARTART editorial are addressed via and .
and .
Looks good Reviewer: Christian Amsüss Review result: Ready with Nits Thanks for this well-written document ART topics: The document does not touch on any of the typical ART review issues; times are relative in well understood units, and versioning, formal language (ASN.1, which is outside of my experience to check) and encoding infrastructure (struct) follows TLS practices. General comments: The introduction of this mechanism gives the impression of a band-aid applied to a PKI ecosystem that has accumulated many limitations as outlined in section The present solution appears good, but if there is ongoing work on the underlying issues (even experimentally), I'd appreciate a careful reference to it. Section 7.6 hints at the front end querying the back-end for creation of new DCs -- other than that, DC distribution (neither push- nor pull-based) is discussed. If there are any mechanisms brewing, I'd appreciate a reference as well. Please check: The IANA considerations list "delegated_credential" for CH, CR and CT messages. I did not find a reference in the text for Ct, only for CH and CR. Editorial comments: (p5) "result for the peer.." -- extraneous period. (p9, p15, p16) The "7 days" are introduced as the default for a profilable prarameter, but later used without further comment.
Reviewer: Elwyn Davies Review result: Ready with Nits I am the assigned Gen-ART reviewer for this draft. The General Area Review Team (Gen-ART) reviews all IETF documents being processed by the IESG for the IETF Chair. Please treat these comments just like any other last call comments. For more information, please see the FAQ at . Document: draft-ietf-tls-subcerts-?? Reviewer: Elwyn Davies Review Date: 2022-04-08 IETF LC End Date: 2022-04-08 IESG Telechat date: Not scheduled for a telechat Summary: Ready with nits. Just a few editrial level nits. Major issues: None Minor issues: None. Nits/editorial comments: Abstract: The exact form of the abbreviation (D)TLS is not in the set of well-known abbreviations.

I assume it is supposed to mean DTLS or TLS - This ought to be expanded on first use. Abstract: s/mechanism to to/mechanism to/ s1, para 2: CA is used before its expansion in para 3. s1, next to last para: "this document proposes" Hopefully when it becomes an RFC it will do more than propose. Suggest "this document introduces". s1, next to last para: "to speak for names" sounds a bit anthropomorphic to me, but I can't think of a simple alternative word. s1, last para: s/We will refer/This document refers/ [Not an academic paper!] s3.1, 2nd bullet: s/provide are not necessary/provide is not necessary/ s4, definition of expectedcertverify_algorithm: " Only signature algorithms allowed for use in CertificateVerify message are allowed." Does this need a reference to the place where the list of such algorithms is recorded? s4.1.1 and s4.1.2: In s4.1.1: "the client SHOULD ignore delegated credentials sent as extensions to any other certificate." I would have though this ought to be a MUST. There is an equivalent in s4.1.2. I am not sure what the client/server might do if it doesn't ignore the DC. s4.1.3, para 1: s/same way that is done/same way that it is done/ s4.2, para 1: s/We define/This docuent defines/ sS/s5.1: RFC conventions prefer not to have sections empty of text: Add something like: "The following operational consideration should be taken into consideration when using Delegated Certificates:"