Shepherd writeup

As required by RFC 4858, this is the current template for the Document 
Shepherd Write-Up. Changes are expected over time. 

This version is dated 1 November 2019.

(1) What type of RFC is being requested (BCP, Proposed Standard, Internet Standard, Informational, Experimental, or Historic)? Why is this the proper type of RFC? Is this type of RFC indicated in the title page header? 

Proposed Standard. The title page shows Standards Track as the Intended Status, which is appropriate given the impact on other standards track documents.

(2) The IESG approval announcement includes a Document Announcement Write-Up. Please provide such a Document Announcement Write-Up. Recent examples can be found in the "Action" announcements for approved documents. The approval announcement contains the following sections: 

Technical Summary:

Relevant content can frequently be found in the abstract and/or introduction of the document. If not, this may be an indication that there are deficiencies in the abstract or introduction. 

This specification defines a new Session Description Protocol (SDP) Grouping Framework extension called 'BUNDLE'.  The extension can be used with the SDP offer/answer mechanism to negotiate the usage of a single transport (5-tuple) for sending and receiving media described by multiple SDP media descriptions ("m=" sections).  Such transport is referred to as a BUNDLE transport, and the media is referred to as bundled media.  The "m=" sections that use the BUNDLE transport form a BUNDLE group.

This specification defines a new RTP Control Protocol (RTCP) Source Description (SDES) item and a new RTP header extension.

This specification updates RFCs 3264, 5888, and 7941.

This specification obsoletes RFC 8843.

Working Group Summary:

Was there anything in WG process that is worth noting? For example, was there controversy about particular points or were there decisions where the consensus was particularly rough? 

When RFC 8843 was published, there was a known inconsistency with JSEP (RFC 8829). This document corrects that inconsistency and incorporates two erratas as well. The nature of the update was agreed to beforehand with the RTCWeb WG and MMUSIC WG participants and the scope of the update was explicitly limited accordingly. There has been no subsequent disagreements or concerns raised. 

Document Quality:

Are there existing implementations of the protocol? Have a significant number of vendors indicated their plan to implement the specification? Are there any reviewers that merit special mention as having done a thorough review, e.g., one that resulted in important changes or a conclusion that the document had no substantive issues? If there was a MIB Doctor, YANG Doctor, Media Type or other expert review, what was its course (briefly)? In the case of a Media Type review, on what date was the request posted? 

The protocol is an important part of the RTCWeb suite of specifications and browser vendors have either implemented or are planning to implement the specification. 

Paul Kyzivat and Roman Shpount both provided good reviews. 


Who is the Document Shepherd? Who is the Responsible Area Director? 

Flemming Andreasen is the Document Shepherd
Murray Kucherawy is the Responsible Area Director

(3) Briefly describe the review of this document that was performed by the Document Shepherd. If this version of the document is not ready for publication, please explain why the document is being forwarded to the IESG. 

I have reviewed the current version of the document in detail. Several WG participans have done the same. The document is ready to proceed. 

(4) Does the document Shepherd have any concerns about the depth or breadth of the reviews that have been performed? 

No such concerns 

(5) Do portions of the document need review from a particular or from broader perspective, e.g., security, operational complexity, AAA, DNS, DHCP, XML, or internationalization? If so, describe the review that took place. 


(6) Describe any specific concerns or issues that the Document Shepherd has with this document that the Responsible Area Director and/or the IESG should be aware of? For example, perhaps he or she is uncomfortable with certain parts of the document, or has concerns whether there really is a need for it. In any event, if the WG has discussed those issues and has indicated that it still wishes to advance the document, detail those concerns here. 


(7) Has each author confirmed that any and all appropriate IPR disclosures required for full conformance with the provisions of BCP 78 and BCP 79 have already been filed. If not, explain why?

Each author has confirmed

(8) Has an IPR disclosure been filed that references this document? If so, summarize any WG discussion and conclusion regarding the IPR disclosures. 

No IPR disclosure

(9) How solid is the WG consensus behind this document? Does it represent the strong concurrence of a few individuals, with others being silent, or does the WG as a whole understand and agree with it? 

There is solid consensus behind the document, incl. overall alignment with the RTCWeb WG and the accompanying JSEP specification (RFC 8829). While the document has been formally reviewed by the MMUSIC group only, please note that there is substantial overlap between the WG participants in MMUSIC and RTCWeb and the document has been reviewed by known RTCWeb WG participants in MMUSIC. Also, the MMUSIC WG Last Call announcement was sent to the RTCWeb group mailing list. 

(10) Has anyone threatened an appeal or otherwise indicated extreme discontent? If so, please summarise the areas of conflict in separate email messages to the Responsible Area Director. (It should be in a separate email because this questionnaire is publicly available.) 


(11) Identify any ID nits the Document Shepherd has found in this document. (See and the Internet-Drafts Checklist). Boilerplate checks are not enough; this check needs to be thorough. 

No nits have been found. Remaining ID-nits check issues are all false positives, incl. the reference to the obsolete RFC 4566, which is retained on purpose (see below as well). 

(12) Describe how the document meets any required formal review criteria, such as the MIB Doctor, YANG Doctor, media type, and URI type reviews. 


(13) Have all references within this document been identified as either normative or informative? 


(14) Are there normative references to documents that are not ready for advancement or are otherwise in an unclear state? If such normative references exist, what is the plan for their completion? 


(15) Are there downward normative references references (see RFC 3967)? If so, list these downward references to support the Area Director in the Last Call procedure. 

The document contains a normative reference to RFC 4566, which has been obsoleted by RFC 8566. RFC 8843 (i.e. the previous version of this specification) contained this obsolete reference as well. Note that RFC 8843 was part of the so-called “Cluster 238” set of documents, where it was agreed to reference RFC 4566 rather than RFC 8566. Replacing the RFC 4566 reference with a reference to RFC 8566 is outside the scope of the agreed to updates in this 8843bis document and it may impact existing implementations and other “Cluster 238” documents as well. 

(16) Will publication of this document change the status of any existing RFCs? Are those RFCs listed on the title page header, listed in the abstract, and discussed in the introduction? If the RFCs are not listed in the Abstract and Introduction, explain why, and point to the part of the document where the relationship of this document to the other RFCs is discussed. If this information is not in the document, explain why the WG considers it unnecessary. 

The document obsoletes RFC 8843 and it updates RFCs 3264, 5888 and 7941, all of which is indicated on the title page and called out in the abstract and introduction. 

(17) Describe the Document Shepherd's review of the IANA considerations section, especially with regard to its consistency with the body of the document. Confirm that all protocol extensions that the document makes are associated with the appropriate reservations in IANA registries. Confirm that any referenced IANA registries have been clearly identified. Confirm that newly created IANA registries include a detailed specification of the initial contents for the registry, that allocations procedures for future registrations are defined, and a reasonable name for the new registry has been suggested (see RFC 8126). 

IANA considerations have been reviewed. Registrations are consistent with the main body of the document and the relevant registry requirements. 

(18) List any new IANA registries that require Expert Review for future allocations. Provide any public guidance that the IESG would find useful in selecting the IANA Experts for these new registries. 


(19) Describe reviews and automated checks performed by the Document Shepherd to validate sections of the document written in a formal language, such as XML code, BNF rules, MIB definitions, YANG modules, etc.


(20) If the document contains a YANG module, has the module been checked with any of the recommended validation tools ( for syntax and formatting validation? If there are any resulting errors or warnings, what is the justification for not fixing them at this time? Does the YANG module comply with the Network Management Datastore Architecture (NMDA) as specified in RFC8342?