I am the assigned Gen-ART reviewer for this draft. For background on Gen-ART, please see the FAQ at < http://wiki.tools.ietf.org/area/gen/trac/wiki/GenArtfaq>. Please resolve these comments along with any other Last Call comments you may receive. Document: draft-ietf-sipcore-rfc3265bis-07.txt Reviewer: Alexey Melnikov Review Date: 10-April-2012 IETF LC End Date: past IESG Telechat date: 26-April-2012 Summary: This documents is ready for publication as a Proposed Standard RFC (with nits). But please see a couple of questions below. 3.2.1. Identification of Reported Events, Event Classes, and Current State When present, the body of the NOTIFY request MUST be formatted into one of the body formats specified in the "Accept" header field of the corresponding SUBSCRIBE request. This body will contain either the state of the subscribed resource or a pointer to such state in the form of a URI (see Section 5.4.13). Nit: or the default according to the event package definition, if no Accept header field was specified. Also, it might be good to reference RFC 3986 for URIs here. 4.1.1. Detecting Support for SIP Events The extension described in this document does not make use of the use of "Require" or "Proxy-Require" header fields; similarly, there is no Nit: too many "use of". token defined for "Supported" header fields. Potential subscribers may probe for the support of SIP Events using the OPTIONS request defined in [RFC3261]. 4.1.3. Receiving and Processing State Information To prevent spoofing of events, NOTIFY requests SHOULD be authenticated, using any defined SIP authentication mechanism. Minor: How can this SHOULD be satisfied? Any reference which might be appropriate here? 4.2.1.3. Authentication/Authorization of SUBSCRIBE Requests SIP authentication mechanisms are discussed in [RFC3261]. Note that, even if the notifier node typically acts as a proxy, authentication for SUBSCRIBE requests will always be performed via a "401" response, not a "407;" notifiers always act as a user agents when accepting Nit: Is the ";" after "407" a typo? subscriptions and sending notifications. 4.4.4. Allow-Events header field usage The "Allow-Events" header field does not include a list of the etvent typo: event template packages supported by an implementation. If a subscriber wishes to determine which event template packages are supported by a notifier, it can probe for such support by attempting to subscribe to the event template packages it wishes to use. Can you clarify how such request would look like? An example would be nice. 5.4.3. SUBSCRIBE Request Bodies It is expected that most, but not all, event packages will define syntax and semantics for SUBSCRIBE request bodies; these bodies will typically modify, expand, filter, throttle, and/or set thresholds for the class of events being requested. Designers of event packages are strongly encouraged to re-use existing MIME types for message bodies where practical. Nit: MIME types are now called "media types" in more recent IETF RFCs. I would recommend pointing to the Media Type Registration Procedure document [RFC 4288] here, which points to the IANA registry. 5.4.5. NOTIFY Request Bodies Event packages also MUST define which MIME type is to be assumed if none are specified in the "Accept" header field of the SUBSCRIBE request. The same nit as above. 7.2. Reason Codes This document further defines "reason" codes for use in the "Subscription-State" header field (see Section 4.1.3). Following the policies outlined in "Guidelines for Writing an IANA Considerations Section in RFCs" [RFC5226], new reason codes require a Standards Action. Minor: This would prevent registration of new Reason Codes in an Experimental RFC (for example). I would like to double check that that is intentional. Registrations with the IANA include the reason code being registered and a reference to a published document which describes the event package. Insertion of such values takes place as part of the RFC publication process or as the result of inter-SDO liaison activity. I don't think Standards Action allows for "inter-SDO liaison activity", unless such documents from other SDOs are published as Standard Track RFCs. So I find your text confusing: either your registration procedure should also allow for direct IESG approvals (to allow registrations from other SDOs with no RFCs), or you should remove "as the result of inter-SDO liaison activity". New reason codes must conform to the syntax of the ABNF "token" element defined in [RFC3261]. 8.4. Augmented BNF Definitions event-type = event-package *( "." event-template ) Minor: Does this mean that multiple template packages can be applied? Is there any ordering for them? How would "foo.A.B" differ from "foo.B.A"? Nit: id-nits complains: -- Duplicate reference: RFC4660, mentioned in 'RFC4660', was also mentioned in 'RFC 4660'. "[RFC 4660]" reference is used in section 7.2.