Extensions to the Path Computation Element Communication Protocol (PCEP) to Compute Service-Aware Label Switched Paths (LSPs)
draft-ietf-pce-pcep-service-aware-13

[Ballot comment]
I am concerned that the 24 bit values of microseconds are being represented in IEEE 32-bit floating point.
A quick look at conversions indicates that all integers will up to 6 significant figures can be converted without
loss of precision.  That implies that values of over 1 second may not be accurately sent.  It would be useful to
at least refer to the precision issue in the document.  I don't expect that the loss of precision at the microsecond
level is critical.

[Ballot comment]
The document should probably say more about how frequently information can be updated and recomputation can occur; there's a possibility that too frequent adjustment creates a flip flop effect where traffic moves to a new path, performance degrades, etc.

I was curious about the definition of the P2MP packet loss as being the highest among the individual path losses. Is there some basis in some measurement documents for instance for this definition? It would seem to me that other definitions would also be possible, e.g., ones that take the aggregate loss into account in some fashion.

[Ballot comment]
I have quite a few comments and some parts really need fixing as things seems wrong to me. However, all these things are no big issues in itself that do not justify a discuss. I strongly recommend to discuss these points and apply changes where appropriate to make these metrics useful by providing the right information.

- This doesn't seem right to mean:
"The link bandwidth utilization (the total
  bandwidth of a link in current use for the forwarding)"
Especially the word "current" is irritating as I strongly assume you'd be interested in something like the average utilization...?

- In general I would clarify that you always talk about averages and not the current values because those change too dynamically to use them for path computation.

- section 3 could be removed. It didn't really help me and the normative language here is actually a little bit confusing to me.

- section 4.2.1: This also doesn't seem to be fully correct:
"An implementation,
  therefore, MAY use the sum of the average delay variation of links
  along a path to derive the average delay variation of the Path."
I would assume that the average path delay variation is NOT the sum of the link variation.
What you get is the maximum variation of the average link delay variation... not sure if that's the best metric to provide for path computation.
Maybe it would be more useful to use the maximum of the average link delay variation as an extimate for the path delay variation?

Also not sure what exactly the next sentence should tell me:
"An implementation MAY also use some enhanced composition function for
  computing the average delay variation of a path."

- OLD:
"The value for the P2MP path delay metric type (T) = TBD8 is to be
  assigned by IANA."
NEW:
"The value for the P2MP path delay metric type (T) is TBD8."
Also in the next two sections...

- The term "Link Bandwidth Utilization (LBU)" is really confusing because I thought that utilization always is a value in percentage. I would propose to go inline with [RFC7471] and [RFC7810] and call it "Utilized Link Bandwidth"! (Similar for next section)

- section 4.2.2.: Really?
"The actual bandwidth by non-RSVP-TE
  traffic can be calculated by subtracting the available Bandwidth from
  the residual Bandwidth ([RFC7471] and [RFC7810]).  Once we have the
  actual bandwidth for non-RSVP TE traffic, subtracting this from LBU
  would result in LRBU."
Isn't the bandwidth utilization/ulilized bandwidth inculding the Link Reserved Bandwidth Utilization...? Not sure if I get this part correctly...

- section 4.2.3.1:
OLD
"A PCE that supports this object MUST ensure that no link on
  the computed path has bandwidth utilization (LBU or LRBU percentage)
  exceeding the given value."
NEW
"A PCE that supports this object MUST compute a path with LBU or LRBU percentage that does not
  exceed the given value."
I don't think the thing stated in the original sentence is possible based on the given information in the LBU/LRBU.

- "If, for a given request, two or more instances
  of a BU object with the same type are present, only the first
  instance MUST be considered and other instances MUST be ignored."
Maybe it's better to consider the lowest value instead of the first instance?

- "If a PCE receives a PCReq message containing a BU object, and the PCE
  does not understand or support the BU object, and the P bit is clear
  in the BU object header then the PCE SHOULD simply ignore the BU
  object."
  Isn't this the default behavior? How should a PCE that does support this draft/understand the BU object do any actions...?
Similar, the next part:
"If the PCE does not understand the BU object, and the P bit is set in
  the BU object header, then the PCE MUST send a PCErr message
  containing a PCEP-ERROR Object with Error-Type = 3 (Unknown object)
  and Error-value = 1 (Unrecognized object class) as per [RFC5440]."
Just remove those two paragraphs...?

- In general, had the feeling that the order of the document is a little up-side-down. However, I'm not sure if changing the order helps. Maybe double-check (also to avoid redunancy)!

[Ballot comment]
- This doesn't seem right to mean:
"The link bandwidth utilization (the total
  bandwidth of a link in current use for the forwarding)"
Especially the word "current" is irritating as I strongly assume you'd be interested in something like the average utilization...?

- In general I would clarify that you always talk about averages and not the current values because those change too dynamically to use them for path computation.

- section 3 could be removed. It didn't really help me and the normative language here is actually a little bit confusing to me.

- section 4.2.1: This also doesn't seem to be fully correct:
"An implementation,
  therefore, MAY use the sum of the average delay variation of links
  along a path to derive the average delay variation of the Path."
I would assume that the average path delay variation is NOT the sum of the link variation.
What you get is the maximum variation of the average link delay variation...
Maybe it would be more useful to use the maximum of the average link delay variation as an extimate for the path delay variation?

Also not sure what exactly the next sentence should tell me:
"An implementation MAY also use some enhanced composition function for
  computing the average delay variation of a path."

- OLD:
"The value for the P2MP path delay metric type (T) = TBD8 is to be
  assigned by IANA."
NEW:
"The value for the P2MP path delay metric type (T) is TBD8."
Also in the next two sections...

- The term "Link Bandwidth Utilization (LBU)" is really confusin because I thought that utilization always a value in percentage. I would propose to go inline with [RFC7471] and [RFC7810] and call it "Utilized Link Bandwidth"! (Similar for next section)

- section 4.2.2.: Really?
"The actual bandwidth by non-RSVP-TE
  traffic can be calculated by subtracting the available Bandwidth from
  the residual Bandwidth ([RFC7471] and [RFC7810]).  Once we have the
  actual bandwidth for non-RSVP TE traffic, subtracting this from LBU
  would result in LRBU."
Isn't the bandwidth utilization/ulilized bandwidth inculding the Link Reserved Bandwidth Utilization...?

- section 4.2.3.1:
OLD
"A PCE that supports this object MUST ensure that no link on
  the computed path has bandwidth utilization (LBU or LRBU percentage)
  exceeding the given value."
NEW
"A PCE that supports this object MUST compute a path with LBU or LRBU percentage that does not
  exceed the given value."
I don't the thing stated in the original sentence is possible based on the given information in the LBU/LRBU.

- "If, for a given request, two or more instances
  of a BU object with the same type are present, only the first
  instance MUST be considered and other instances MUST be ignored."
Maybe it's better to consider the lowesz value instead of the first instance?

- "If a PCE receives a PCReq message containing a BU object, and the PCE
  does not understand or support the BU object, and the P bit is clear
  in the BU object header then the PCE SHOULD simply ignore the BU
  object."
  Isn't this the default behavior? How should a PCE that does support this draft/understand the BU object do any actions...?
Similar, the next part:
"If the PCE does not understand the BU object, and the P bit is set in
  the BU object header, then the PCE MUST send a PCErr message
  containing a PCEP-ERROR Object with Error-Type = 3 (Unknown object)
  and Error-value = 1 (Unrecognized object class) as per [RFC5440]."

[Ballot comment]
- This doesn't seem right to mean:
"The link bandwidth utilization (the total
  bandwidth of a link in current use for the forwarding)"
Especially the word "current" is irritating as I strongly assume you'd be interested in something like the average utilization...?

- In general I would clarify that you always talk about averages and not the current values because those change too dynamically to use them for path computation.

- section 3 could be removed. It didn't really help me and the normative language here is actually a little bit confusing to me.

- section 4.2.1: This also doesn't seem to be fully correct:
"An implementation,
  therefore, MAY use the sum of the average delay variation of links
  along a path to derive the average delay variation of the Path."
I would assume that the average path delay variation is NOT the sum of the link variation.
What you get is the maximum variation of the average link delay variation...
Maybe it would be more useful to use the maximum of the average link delay variation as an extimate for the path delay variation?

Also not sure what exactly the next sentence should tell me:
"An implementation MAY also use some enhanced composition function for
  computing the average delay variation of a path."

- OLD:
"The value for the P2MP path delay metric type (T) = TBD8 is to be
  assigned by IANA."
NEW:
"The value for the P2MP path delay metric type (T) is TBD8."
Also in the next two sections...

- The term "Link Bandwidth Utilization (LBU)" is really confusin because I thought that utilization always a value in percentage. I would propose to go inline with [RFC7471] and [RFC7810] and call it "Utilized Link Bandwidth"! (Similar for next section)

- section 4.2.2.: Really?
"The actual bandwidth by non-RSVP-TE
  traffic can be calculated by subtracting the available Bandwidth from
  the residual Bandwidth ([RFC7471] and [RFC7810]).  Once we have the
  actual bandwidth for non-RSVP TE traffic, subtracting this from LBU
  would result in LRBU."
Isn't the bandwidth utilization/ulilized bandwidth inculding the Link Reserved Bandwidth Utilization...?

[Ballot comment]
The security sections of the referenced documents look very good.  The one thing I don't see mentioned is use of these metrics to perform network reconnaissance to perform other attacks.  I'm also interested to see the responses to Stephen's questions.

Thanks.

[Ballot comment]

- You're missing a reference for TCP-AO (RFC5925 I
guess)

- My understanding is that TCP-AO is not widely
deployed. If it is expected that PCEPS will be, then
it'd maybe be good to indicate that in section 9.

- I would have thought that these extensions would
provide new ways in which networks could lie about
things in order to influence what paths are chosen.
Is that new or was it already considered in the
referenced RFCs? (Sorry, didn't have time to check
right now.) If it is new, maybe it's worth a mention?
Note: I'm not suggesting that this document specify
the one true way to deal with that, just that it be
noted, if it's useful to do that, but given one
motivation offered is financial services, presumably
not everyone trusts everyone to be entirely honest;-)

[Ballot comment]
ALFRED MORTON  performed the opsdir review.

subject to the discussion on the caculation of the path delay variation metric coming to a close, I have no objections.

[Ballot comment]
A few minor, mostly editorial comments:

- Abstract: The abstract seems unnecessarily long.  The point is to describe very briefly what the document is about. The more “motivating” text could be left to the intro.

-3: Will this section have value to readers of the RFC, once the RFC is published?

- General:  A lot (if not most) of the instances of “MAY” would better serve as “can”. They seem to be saying that it is possible for an element to do something, rather than offering permission to do that thing.

(Via drafts-lastcall-comment@iana.org): IESG/Authors/WG Chairs:

IANA has completed its review of draft-ietf-pce-pcep-service-aware-12.txt. If any part of this review is inaccurate, please let us know.

IANA understands that, upon approval of this document, there are five actions which IANA must complete.

First, in the METRIC object T field subregistry of the Path Computation Element Protocol (PCEP) Numbers registry located at:

http://www.iana.org/assignments/pcep/

six new registrations are to be made as follows:

Value: [ TBD-at-registration ]
Description: Path Delay metric
Reference: [ RFC-to-be ]

Value: [ TBD-at-registration ]
Description: Path Delay Variation metric
Reference: [ RFC-to-be ]

Value: [ TBD-at-registration ]
Description: Path Loss metric
Reference: [ RFC-to-be ]

Value: [ TBD-at-registration ]
Description: P2MP Path Delay metric
Reference: [ RFC-to-be ]

Value: [ TBD-at-registration ]
Description: P2MP Path Delay variation metric
Reference: [ RFC-to-be ]

Value: [ TBD-at-registration ]
Description: P2MP Path Loss metric
Reference: [ RFC-to-be ]

Second, in the PCEP Objects subregistry also in the Path Computation Element Protocol (PCEP) Numbers registry located at:

http://www.iana.org/assignments/pcep/

a single, new object is to be registered as follows:

Object Class: [ TBD-at-registration ]
Object Type: 1
Name: BU
Reference: [ RFC-to-be ]

Third, a new registry called the BU Object Type Field registry is to be created in the Path Computation Element Protocol (PCEP) Numbers registry located at:

http://www.iana.org/assignments/pcep/

The registry will be managed via Standards Action as defined in RFC 5226. There are initial registrations in the new registry as follows:

Type Name Reference
-----------------------------------------------------
1 LBU (Link Bandwidth [ RFC-to-be ]
Utilization
2 LRBU (Link Residual [ RFC-to-be ]
Bandwidth Utilization

Fourth, in the Objective Funcation subregistry also in the Path Computation Element Protocol (PCEP) Numbers registry located at:

http://www.iana.org/assignments/pcep/

three new registrations are to be made as follows:

Code Point: [ TBD-at-registration ]
Name: Minimum Packet Loss Path (MPLP)
Reference: [ RFC-to-be ]

Code Point: [ TBD-at-registration ]
Name: Maximum Under-Utilized Path (MUP)
Reference: [ RFC-to-be ]

Code Point: [ TBD-at-registration ]
Name: Maximum Reserved Under-Utilized Path (MRUP)
Reference: [ RFC-to-be ]

Fifth, in the PCEP-ERROR Object Error Types and Values subregistry also in the Path Computation Element Protocol (PCEP) Numbers registry located at:

http://www.iana.org/assignments/pcep/

two new Error-values are defined for the Error-Type "Not supported object" (type 4) and "Policy violation" (type 5). A single, new error value is being added to two existing types as follows

Error-Type Meaning and error values Reference

added to Error-type:
4 Not supported object

Error-value=TBD11 Unsupported [ RFC-to-be ]
network performance constraint

added to Error-type:
5 Policy violation

Error-value=TBD12 Not allowed [ RFC-to-be ]
network performance constraint

IANA understands that the five actions above are the only ones required to be completed upon approval of this document.

Note:  The actions requested in this document will not be completed until the document has been approved for publication as an RFC. This message is only to confirm what actions will be performed. 

Thank you,

Sabrina Tanamal
IANA Specialist
ICANN

The following Last Call announcement was sent out:

From: The IESG
To: "IETF-Announce"
CC: draft-ietf-pce-pcep-service-aware@ietf.org, db3546@att.com, "Jonathan Hardwick" , pce@ietf.org, pce-chairs@ietf.org, jonathan.hardwick@metaswitch.com
Reply-To: ietf@ietf.org
Sender:
Subject: Last Call:  (Extensions to the Path Computation Element Communication Protocol (PCEP) to compute service aware Label Switched Path (LSP).) to Proposed Standard


The IESG has received a request from the Path Computation Element WG
(pce) to consider the following document:
- 'Extensions to the Path Computation Element Communication Protocol
  (PCEP) to compute service aware Label Switched Path (LSP).'
  as Proposed Standard

The IESG plans to make a decision in the next few weeks, and solicits
final comments on this action. Please send substantive comments to the
ietf@ietf.org mailing lists by 2016-09-06. Exceptionally, comments may be
sent to iesg@ietf.org instead. In either case, please retain the
beginning of the Subject line to allow automated sorting.

Abstract


  In certain networks, such as, but not limited to, financial
  information networks (e.g. stock market data providers), network
  performance criteria (e.g. latency) are becoming as critical to data
  path selection as other metrics and constraints.  These metrics are
  associated with the Service Level Agreement (SLA) between customers
  and service providers.  The link bandwidth utilization (the total
  bandwidth of a link in current use for the forwarding) is another
  important factor to consider during path computation.

  IGP Traffic Engineering (TE) Metric extensions describe mechanisms
  with which network performance information is distributed via OSPF
  and IS-IS respectively.  The Path Computation Element Communication
  Protocol (PCEP) provides mechanisms for Path Computation Elements
  (PCEs) to perform path computations in response to Path Computation
  Clients (PCCs) requests.  This document describes the extension to
  PCEP to carry latency, delay variation, packet loss and link
  bandwidth utilization as constraints for end to end path computation.




The file can be obtained via
https://datatracker.ietf.org/doc/draft-ietf-pce-pcep-service-aware/

IESG discussion can be tracked via
https://datatracker.ietf.org/doc/draft-ietf-pce-pcep-service-aware/ballot/


No IPR declarations have been submitted directly on this I-D.


The document contains these normative downward references.
See RFC 3967 for additional information:
    draft-ietf-pce-stateful-pce: PCEP Extensions for Stateful PCE (None - IETF stream)
Note that some of these references may already be listed in the acceptable Downref Registry.

(1) What type of RFC is being requested (BCP, Proposed Standard,
Internet Standard, Informational, Experimental, or Historic)?

  Proposed standard.

Why is this the proper type of RFC?

  It defines protocol extensions to Path Computation Element Protocol (PCEP).

Is this type of RFC indicated in the title page header?

  Yes.


(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 describes extensions to Path Computation Element Communication
  Protocol (PCEP) to carry latency, delay variation, packet loss and link
  bandwidth utilization as constraints for end to end path computation.

Working Group Summary

  There were no contentious issues while the working group worked on this
  document.

Document Quality

  At least one implementation of this protocol exists.
  The document did not receive many comments on-list in the
  PCE working group.  It received a Performance Metrics
  Directorate review.

Personnel

  Jonathan Hardwick is the Document Shepherd.  Deborah Brungard 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 reviewed the document during working group last call.  The
  protocol changes are straightforward.


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

  Besides mine, there were not many reviews of this document posted to
  the mailing list.  However, the document has a good range of authors and
  contributors, and support for this document from the WG does seems to
  be there.


(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.

  N/A.


(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.

  N/A.


(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, on the PCE mailing list.


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

  N/A.


(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 WG supports publication of the document.


(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 https://www.ietf.org/tools/idnits/ and the Internet-Drafts
Checklist). Boilerplate checks are not enough; this check needs to be
thorough.

  N/A.


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

  N/A.


(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?

  Yes.  It has a normative reference to draft-ietf-pce-stateful-pce, which is not quite ready for advancement, but which should advance soon.


(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.


(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).

  IANA actions are clearly specified, covering all protocol extensions.
  One new sub-registry is created and is fully specified.


(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.

  N/A.


(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.

(1) What type of RFC is being requested (BCP, Proposed Standard,
Internet Standard, Informational, Experimental, or Historic)?

  Proposed standard.

Why is this the proper type of RFC?

  It defines protocol extensions to Path Computation Element Protocol (PCEP).

Is this type of RFC indicated in the title page header?

  Yes.


(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 describes extensions to Path Computation Element Communication
  Protocol (PCEP) to carry latency, delay variation, packet loss and link
  bandwidth utilization as constraints for end to end path computation.

Working Group Summary

  There were no contentious issues while the working group worked on this
  document.

Document Quality

  At least one implementation of this protocol exists.
  The document did not receive many comments on-list in the
  PCE working group.  It received a Performance Metrics
  Directorate review.

Personnel

  Jonathan Hardwick is the Document Shepherd.  Deborah Brungard 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 reviewed the document during working group last call.  The
  protocol changes are straightforward.


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

  Besides mine, there were not many reviews of this document posted to
  the mailing list.  However, the document has a good range of authors and
  contributors, and support for this document from the WG does seems to
  be there.


(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.

  N/A.


(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.

  N/A.


(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, on the PCE mailing list.


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

  N/A.


(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 WG supports publication of the document.


(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 https://www.ietf.org/tools/idnits/ and the Internet-Drafts
Checklist). Boilerplate checks are not enough; this check needs to be
thorough.

  N/A.


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

  N/A.


(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.


(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.


(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).

  IANA actions are clearly specified, covering all protocol extensions.
  One new sub-registry is created and is fully specified.


(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.

  N/A.


(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.