Subject: [tsvwg] Shepherd Write-Up for draft-ietf-tsvwg-sctp-failover

From: Gorry Fairhurst <[email-masked]>
Date: Mon, 21 Sep 2015 12:01:31 +0100

As a WG Chair, I am pleased to note the support of the TSV WG in 
progressing this document towards standards publication as a PS, and 
enclose here the writeup to our AD requesting publication.

Gorry Fairhurst
(tsvwg co-chair)

---

draft-ietf-tsvwg-sctp-failover

As required by RFC4858, this is the current template for the Document 
Shepherd Write-Up.

Changes are expected over time. This version is dated 24 February 2012.

(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?

PS

(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:

This describes a standards-track procedure for SCTP to support of 
failover when working with a multi-homed SCTP end-point:

    SCTP supports multi-homing.  However, when the failover operation
    specified in RFC4960 is followed, there can be significant delay and
    performance degradation in the data transfer path failover.  To
    overcome this problem this document specifies a quick failover
    algorithm (SCTP-PF) based on the introduction of a Potentially Failed
    (PF) state in SCTP Path Management.

    The document also specifies a dormant state operation of SCTP.  This
    dormant state operation is required to be followed by an SCTP-PF
    implementation, but it may equally well be applied by a standard
    RFC4960 SCTP implementation.

    Additionally, the document introduces an alternative switchback
    operation mode called Primary Path Switchover that will be beneficial
    in certain situations.  This mode of operation applies to both a
    standard RFC4960 SCTP implementation as well as to a SCTP-PF
    implementation.

    The procedures defined in the document require only minimal
    modifications to the RFC4960 specification.  The procedures are
    sender-side only and do not impact the SCTP receiver.

Working Group Summary:

Document Quality:
The document is thought ready to publish.

Personnel:

Who is the Document Shepherd?
G Fairhurst (TSVWG Co-Chair)

Who is the Responsible Area Director?
Spencer Dawkins (TSV 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.

I have reviewed this document a number of times, and the requested 
improvements in quality and readability have been incorporated. I am 
happy the final document is ready to publish.

The feature specified by this document is implemented by multiple SCTP 
SW implementations and furthermore that various variants of the solution 
have been deployed in Telco signaling environments for several years 
with good results.

PF has been coded into FreeBSD, and plans to update to this spec.
Ericsson SW (supported in various forms for 5 years)
This feature is supported in Ericsson in-house SCTP SW implementation, 
and available for use in other stacks.

It is partially implemented in Linux SCTP SW (July 2014) with the intent 
to implement.

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

No.

(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.

(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.

(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?

OK - Yoshifumi Nishida <[email-masked]>
OK - Preethi Natarajan <[email-masked]>
OK - Armando Caro <[email-masked]>
OK - P. Amer <[email-masked]>
OK - K. Nielsen <[email-masked]>

(OK means the authors have confirmed that they comply withe provisions).

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

None known.

(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 document received support from TSVWG.

This document has received appropriate review by the TSV WG: The 
document was adopted by WG 26/6/2012. It has been reviewed by principal 
SCTP maintainers. A WGLC concluded 19th November, 2014 and was followed 
by significant work to improve the quality of the document and 
specification of the protocol. At the end of this updates  the authors 
worked with people raising comments to confirm the set of changes and a 
final 2 week WGLC in Sept 2015 confirmed acceptance of the final 
document by the TSVWG.

(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.)

No

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

None

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

None

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

Yes

(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?

OK

(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.

No

(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.

No

It was considered whether this updates the SCTP base specification RFC, 
but after consideration by the WG it was concluded this is an optional 
extension that should not update this spec. This seems in line with the 
update policy for SCTP RFCs.

(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).

This document requires no actions from IANA.

(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.

None

(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.

None