Shepherd writeup

(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?

This document is a proposed standard. It defines a data model for logging SIP messages.

(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:

The Session Initiation Protocol does not have a common log
format, and as a result, each server supports a distinct log format
that makes it unnecessarily complex to produce tools to do trend
analysis and security detection.  This document provides motivation
for a common format and defines a framework and data model for such 
a log as well as a need to allow extensions.

Working Group Summary:

There were some issues with respect the choice of indexed-ascii versus binary 
representation. This stalled the WG progress for a number of meetings. 
There was significant discussion about whether to create this standalone format,
or build withing syslog or IPFix. The technical implications of working within IPFix
were explored and the data model documented here could be used with IPFix. 
The  working group decided to move ahead with the standalone format documented
in draft-ietf-sipclf-format, and this final product has good support in the WG.

A previous version of this document received IESG review. This review raised issues
about the scope of the document (it is more than a problem statement), and technical
concerns involving internationalization.

Document Quality:

There were sample implementations of the indexed ascii format written by 
Peter Musgrave and placed on the sipclf Wiki page 
Vijay Gurbani reports that three other implementations are known.


Peter Musgrave is the document shepherd. Robert Sparks in the responsible AD.

(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.

The post-IESG review document was reviewed by Peter Musgrave and Robert Sparks. Prior to IESG review it had several WG last-Calls.

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

No concerns about the reviews depth/breadth.

(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.

No broader review was deemed necessary.

(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.

No specific concerns.

(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?


(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 has been filed.

(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?

The consensus for the fields which any format solution needs to log have been uncontroversial. The minimal set of fields are basic to any SIP record keeping and an extension mechanism allows customization by those who need more.

The discussion of potential mechanisms and alignment with existing mechanism was more spirited. Syslogand Ipfix logging have had advocates at various times.

The IETF77 minutes record a discussion about a need to look seriously at IPFIX. Syslog was also discussed and a comment made that data was too much for syslog (and was concurred with by chair of syslog).

Some comments made (DaveH) - suggesting syslog needs further scrutiny ( Comments were made expressing concern about binary content in SIP messages (Hadriel Kaplan) and extreme sizes of some elements (Cullen Jennings). Syslog expert (Rainer Gerhards) indicated that the size issues should not be a major concern although there are parts of the syslog community that prefer small sizes. The final email in this chain is and after that no one "went to bat" for syslog and energy went into discussions of IPFIX versus Indexed ASCII.

The IPFIX vs indexed-ASCII discussion lasted for a number of meeting cycles with neither garnering complete support. Over time the group decided to proceed with indexed ascii. There is agreement that the data model defined by sipclf could be used as a basis for an IPFIX format should some future group wish to define one. 

(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.)

There have been no signs of extreme discontent.

(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.

There is one NIT:

== Outdated reference: A later version (-09) exists of


This document is moving to IESG approval in parallel with this document.

(12) Describe how the document meets any required formal review criteria, such as the MIB 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.

There are no down refs.

(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.


(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 5226).


(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, etc.