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.
Document:
Data Fields for In-situ OAM
draft-ietf-ippm-ioam-data-09
Note: This write-up may not be final: see Shepherd's comments at the end.
Date May 30, 2020
(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?
Standards Track, appropriate as a reference for additional RFCs that specify
encapsulations in a variety of protocols, such as Segment Routing, Geneve, or
IPv6. Standards Track is indicated on the title page >>>>>>(but the Datatracker
needs update).
(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 memo describes a specific type of OAM capability intended to operate
within a network domain, and complements traditional measurement tools for
connectivity and route discovery (such as ping and traceroute). This form is
called In-situ-OAM, and the techniques employed fall in the RFC 7799 category
of Hybrid Type I (as a combination of Active measurement using synthetic
traffic and pure Passive observations of user traffic, by adding
measurement-specific information to user traffic). Packets with In-situ OAM
encapsulation record information as they traverse nodes within a specific
network domain. This information includes timestamps, identification of
interfaces, and other details that can assist with OAM activities which include
new ones, such as proof of transit (exactly which nodes/interfaces were
visited). The IOAM encapsulation will be added/removed at domain
ingress/egress, may be added to all or a subset of packets, and updated at all
or a subset of transit nodes. IOAM Namespaces provide another dimension of
flexibility for actions. This memo will be used a as a reference for additional
RFCs that specify encapsulations in a variety of protocols, such as Segment
Routing, Geneve, or IPv6.
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?
This work topic & proposal was bounced-around a bit before finding an
appropriate home in Transport Area and IPPM WG.
Many of the details of IOAM data fields and operations were discussed at length
on e-mail and debated at side meetings. Further the development used GitHub's
capabilities to track issues and the discussion to resolve each item.
https://github.com/inband-oam/ietf/pulls?q=is%3Apr+is%3Aclosed
Note that at the present time (May 29), 2 relevant PRs are open:
https://github.com/inband-oam/ietf/pulls?q=is%3Aopen+is%3Apr
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?
Personnel:
Who is the Document Shepherd? Al Morton
Who is the Responsible Area Director? Martin Duke
(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 Shepherd has reviewed the present draft, and several previous version
dating back to the original proposals. Some of the reviews were prompted by
interaction between IOAM capabilities and the IPPM WG Draft on Route Metrics.
(4) Does the document Shepherd have any concerns about the depth or breadth of
the reviews that have been performed?
No concerns, the review in total has been extensive, with many detailed items
precipitating active discussions.
(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.
The usual Directorate Reviews should be sufficient.
OPS should ensure that Shepherd's comments appended to this form have been
resolved.
(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 concerns. There has been plenty of time for concerns to be expressed and for
consensus to emerge (since July 2016).
(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?
F. Brockners
S. Bhandari
C. Pignataro
H. Gredler
J. Leddy
S. Youell
T. Mizrahi
D. Mozes
P. Lapukhov
R. Chang
D. Bernier
J. Lemon
(8) Has an IPR disclosure been filed that references this document? If so,
summarize any WG discussion and conclusion regarding the IPR disclosures.
There is one IPR Disclosure:
OPERATIONS, ADMINISTRATION, AND MANAGEMENT FIELDS FOR PACKET TRANSPORT
https://datatracker.ietf.org/ipr/3526/
There appears to have been no discussion of this Disclosure when it appeared on
the ippm-list (20 May 2019) to the present.
https://mailarchive.ietf.org/arch/msg/ippm/cYK91eFWvLpaBiLynPFXRh6sKkA/
(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 in the end appears strong, after considerable review and negotiation.
(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 Appeals threatened.
(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.
No problems with nits, several comments on version 09 to check:
== Unused Reference: 'I-D.lapukhov-dataplane-probe' is defined on line
1815, but no explicit reference was found in the text
-- Possible downref: Non-RFC (?) normative reference: ref. 'IEEE1588v2'
-- Possible downref: Non-RFC (?) normative reference: ref. 'POSIX'
(12) Describe how the document meets any required formal review criteria, such
as the MIB Doctor, YANG Doctor, media type, and URI type reviews.
NA
(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?
All Normative References are complete/approved.
(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.
Possibly - see item (11) above.
(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 change of status for other docs.
(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).
This memo creates a new family of registries, and the initial contents have
been carefully provided.
(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.
Most of the Registries are RFC Required, however the IOAM Namespace-ID Registry
entries will be assigned after Expert Review.
(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.
None, NA.
(20) If the document contains a YANG module, has the module been checked with
any of the recommended validation tools
(https://trac.ietf.org/trac/ops/wiki/yang-review-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?
None, NA.
Doc Shepherd's Comments:
1. closed PR https://github.com/inband-oam/ietf/pull/96
Two Comments indicate the value of a Manageability Considerations section while
resolving issues in the discussion. However, the -09 version still does not
have this section a year later... The important topic discussed was congestion
management, but there are no instances of "congest" in the -09 text.
Section 3, Scope, etc. contains topic:
Deployment domain (or scope) of in-situ OAM deployment:, in which many
operational considerations are detailed that could be part of a Manageability
Considerations: section.
4.4 Trace Option types
...
...The maximum
number of hops and the minimum path MTU of the IOAM domain is assumed
to be known.
What are the consequences when they are not known?
Looks like the Flag Bit 0 O-bit handles this case for number of hops.
Or, is this knowledge highly likely, and expected to be violated only under the
most unexpected conditions (restoration from multiple failures)? See point
below on "minimum path MTU".
4.4.1
RemainingLen:
...
Given that the sender knows the minimum path MTU, the sender MAY
set the initial value of RemainingLen according to the number of
node data bytes allowed before exceeding the MTU.
"minimum path MTU" is the smallest Maximum Transmission Unit for all links in a
path, or simply the Path MTU, PMTU, right?
https://en.wikipedia.org/wiki/Path_MTU_Discovery
4.5 Proof of Transit
Is there a Reference for "Shamir's Secret Sharing Schema (SSSS)" ?
Or, is it a secret?
7. IANA Considerations
(apologies in advance for a long/recent/good experience with IANA, and the many
other folks who try to help) This section appears to define a set of related
registries. The Hierarchy could be named a bit more efficiently than:
7.1 In-Situ OAM Protocol Parameters Registry (IOAM) Protocol Parameters IANA
registry
Suggest:
In-Situ OAM (IOAM) Protocol Parameters Group
7.1 IOAM Protocol Parameters Registry
7.2 IOAM Option-Type Registry
7.3 IOAM Trace-Type Registry
...