(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.
This is the appropriate RFC type given the protocol extensions defined within
the document.
(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 document extends Automatic Multicast Tunnelling (AMT, RFC 7450) to allow
the relay discovery process to use a new AMTRELAY DNS resource record for
discovering source-specific multicast channels. This allows a set of AMT
relays that can receive and forward multicast traffic from a sender to be
advertised via reverse IP entries in DNS, hence the DNS Reverse IP AMT
Discovery or DRIAD name.
Working Group Summary:
There was no particular controversy in the WG process, and consensus was good.
Document Quality:
The document is well written, explaining the basic mode of operation clearly,
and including many example use cases.
Personnel:
The document shepherd is Tim Chown (tim.chown@jisc.ac.uk), and the responsible
AD is Warren Kumari.
(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 read the draft, reviewed recent WG list discussion, and am happy that it
is ready overall to be advanced to the IESG.
(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.
I am happy overall with the document.
I would suggest that the text in 2.3.1 on applying a Happy Eyeballs algorithm
where there are multiple choices for the relay be expanded; it is very vague at
present. I presume that this may result in multiple unicast AMT streams coming
in to a given gateway, and all but one of these would be pruned back, but some
specifics on that, and how the preferred stream is retained, would be useful.
This also needs to be set against the proposed active/active failover mode
described in 2.4.3.
While maximising the multicast portion of the path will avoid data duplication
over unicast tunnels, using a relay close to the source (and known to the
source such that it can be added to the DNS reverse zone) has some management
benefits. It’s an interesting trade-off. The document proposes mechanism(s)
to discover topologically close relays; with hindsight perhaps this, and
aspects such as handling active/active failover, should have been covered in a
separate document to a basic DNS RR specification that assumes a single gateway
and single relay near the source.
(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?
Yes. See
https://mailarchive.ietf.org/arch/msg/mboned/Y2xm-oXRFhzKmSXgdu7MrmvaTKc
(8) Has an IPR disclosure been filed that references this document? If so,
summarize any WG discussion and conclusion regarding the IPR disclosures.
No.
(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?
Consensus is good, with no opposition to publication, but mboned is a
relatively small WG with a generally low attendance at meetings. The WGLC in
June passed but needed a prod from the WG chairs and another poke from Warren
as the AD to get additional responses - see
https://mailarchive.ietf.org/arch/msg/mboned/5OzJMfSfWvWq6Nu-SPqdxCMLjSw
Those who did comment were favourable, for example - “This is a very useful
addition to the AMT toolkit, which should encourage the deployment of multicast
services. I therefore support its adoption enthusiastically.” - William Atwood.
(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.
I ran a nits check on the -08 version. See
https://tools.ietf.org/idnits?url=https://tools.ietf.org/id/draft-ietf-mboned-driad-amt-discovery-08.txt
The two warnings about IPv4 literal and multicast addresses appear to be
spurious. This was discussed by the author at
https://mailarchive.ietf.org/arch/msg/mboned/G6rBrnc9u4YCBniAOnZf1-iTQqw It
looks like the nit checker needs a tweak for SSM? Otherwise, the document
passes all nit checks.
(12) Describe how the document meets any required formal review criteria, such
as the MIB Doctor, media type, and URI type reviews.
No such reviews are required.
(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?
No, all references are at RFC status.
(15) Are there downward normative references (see RFC 3967)? If so, list these
downward references to support the Area Director in the Last Call procedure.
None apparent.
(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. Though it does update RFC 7450 by providing a specific DNS-based mechanism
for AMT relay discovery.
(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).
The IANA Considerations are covered in Section 5.
The document requests a new DNS Resource Record Type of type 260.
This type is already listed at
https://www.iana.org/assignments/dns-parameters/dns-parameters.xml, the
reservation of which appears consistent with the document. There is a
sub-registry for the Relay Type field, for which four of 256 possible values
are defined.
(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.
The Relay Type field may potentially have additional values assigned in the
future; as above four of 256 values are defined, the rest (4-255) are
unassigned. The document states that Expert Review would be required for
these, as per Section 4.6 (policy of Specification Required) of RFC 8126.
(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.
N/A.