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TRILL (TRansparent Interconnection of Lots of Links): ECN (Explicit Congestion Notification) Support
draft-ietf-trill-ecn-support-07

Revision differences

Document history

Date Rev. By Action
2024-05-02
07 (System) RFC Editor state changed to RFC-EDITOR from REF
2023-12-14
07 (System) RFC Editor state changed to REF from EDIT
2023-12-06
07 (System) RFC Editor state changed to EDIT from MISSREF
2023-06-07
07 Robert Sparks Restored Martin as the responsible AD
2022-05-19
07 Andrew Alston Shepherding AD changed to Andrew Alston
2019-05-09
07 Alvaro Retana Shepherding AD changed to Martin Vigoureux
2018-03-14
07 (System) IANA Action state changed to RFC-Ed-Ack from Waiting on RFC Editor
2018-03-14
07 (System) IANA Action state changed to Waiting on RFC Editor from Waiting on Authors
2018-03-13
07 (System) IANA Action state changed to Waiting on Authors from In Progress
2018-03-13
07 (System) IANA Action state changed to In Progress from Waiting on Authors
2018-03-13
07 (System) IANA Action state changed to Waiting on Authors from In Progress
2018-03-12
07 (System) RFC Editor state changed to MISSREF
2018-03-12
07 (System) IESG state changed to RFC Ed Queue from Approved-announcement sent
2018-03-12
07 (System) Announcement was received by RFC Editor
2018-03-12
07 (System) IANA Action state changed to In Progress
2018-03-12
07 Amy Vezza IESG state changed to Approved-announcement sent from Approved-announcement to be sent
2018-03-12
07 Amy Vezza IESG has approved the document
2018-03-12
07 Amy Vezza Closed "Approve" ballot
2018-03-12
07 Amy Vezza Ballot approval text was generated
2018-03-09
07 Alia Atlas IESG state changed to Approved-announcement to be sent from IESG Evaluation::AD Followup
2018-02-25
07 Donald Eastlake New version available: draft-ietf-trill-ecn-support-07.txt
2018-02-25
07 (System) New version approved
2018-02-25
07 (System) Request for posting confirmation emailed to previous authors: Bob Briscoe , Donald Eastlake
2018-02-25
07 Donald Eastlake Uploaded new revision
2018-02-25
06 (System) Sub state has been changed to AD Followup from Revised ID Needed
2018-02-25
06 (System) IANA Review state changed to Version Changed - Review Needed from IANA OK - Actions Needed
2018-02-25
06 Donald Eastlake New version available: draft-ietf-trill-ecn-support-06.txt
2018-02-25
06 (System) New version approved
2018-02-25
06 (System) Request for posting confirmation emailed to previous authors: Bob Briscoe , Donald Eastlake
2018-02-25
06 Donald Eastlake Uploaded new revision
2018-02-20
05 Adam Roach
[Ballot comment]
I'm balloting "no objection" based on explanations from the author about
all three points raised in my original discuss. I have requested that …
[Ballot comment]
I'm balloting "no objection" based on explanations from the author about
all three points raised in my original discuss. I have requested that the
authors include a summary of these explanations in the document to
aid implementors in understanding why Table 3 is defined the way it is,
so they don't erroneously conclude that the table is incorrect.

My original discuss text and original comments appear below for posterity.

---------------------------------------------------------------------------

Thanks to the authors, chairs, shepherd, and working group for the effort that
has been put into this document.

I have concerns about some ambiguity and/or self-contradiction in this
specification, but I suspect these should be easy to fix. In particular, the
behavior defined in Table 3 doesn't seem to be consistent with the behavior
described in the prose.

For easy reference, I've copied Table 3 here:

>      +---------+----------------------------------------------+
>      | Inner  |  Arriving TRILL 3-bit ECN Codepoint Name    |
>      | Native  +---------+------------+------------+----------+
>      | Header  | Not-ECT | ECT(0)    | ECT(1)    |    CE  |
>      +---------+---------+------------+------------+----------+
>      | Not-ECT | Not-ECT | Not-ECT(*) | Not-ECT(*) |    |
>      |  ECT(0) |  ECT(0) |  ECT(0)    |  ECT(1)    |    CE  |
>      |  ECT(1) |  ECT(1) |  ECT(1)(*) |  ECT(1)    |    CE  |
>      |    CE  |      CE |      CE    |      CE(*) |    CE  |
>      +---------+---------+------------+------------+----------+
>
>                      Table 3. Egress ECN Behavior
>
>  An asterisk in the above table indicates a currently unused
>  combination that SHOULD be logged. In contrast to [RFC6040], in TRILL
>  the drop condition is the result of a valid combination of events and
>  need not be logged.

The prose in this document indicates:

1. Ingress gateway either copies the native header value to the TRILL ECN
    codepoint (resulting in any of the four values above) or doesn't insert
    any ECN information in the TRILL header.

2. Intermediate gateways can set the CCE flag, resulting in "CE" in the
    table above.

Based on the above, a packet arriving at an egress gateway can only be in one of
the following states:

A. TRILL header is Not-ECT because no TRILL node inserted ECN information.

B. TRILL header value == Native header value because the ingress gateway
    copied it from native to TRILL.

C. TRILL header is "CE" because an intermediate node indicated congestion.

If that's correct, I would think that any state other than those three needs
to be marked with an (*). In particular, these two states fall into that
classification, and seem to require an asterisk:

  - Native==CE && TRILL==ECT(0)

  - Native==ECT(0) && TRILL==ECT(1)

In addition, the behavior this table defines for Native==ECT(0) && TRILL==ECT(1)
is somewhat perplexing: for this case, the value in the TRILL header takes
precedence; however, when Native==ECT(1) && TRILL==ECT(0) the Native header
takes precedence. Or, put another way, this table defines ECT(1) to always
override ECT(0). I don't find any prose in here to indicate why this needs to be
treated differentially, so I'm left to conclude that this is a typographical
error. If that's not the case, please add motivating text to Table 3 explaining
why ECT(1) is treated differently than ECT(0) for baseline ECN behavior.

---------------------------------------------------------------------------

I also have a small handful of editorial suggestions and nits to propose.

Please expand "TRILL" upon first use and in the title; see
https://www.rfc-editor.org/materials/abbrev.expansion.txt for guidance.

---------------------------------------------------------------------------
§1:

>  In [RFC3168] it was recognized that tunnels and lower layer protocols

"In [RFC3168], it was..."
(insert comma)

---------------------------------------------------------------------------

§2:

>  These fields are show in Figure 2 as "ECN" and "CCE". The TRILL-ECN

"...are shown..."


>  The CRItE bit is the critical Ingress-to-Egress summary
>  bit and will be one if and only if any of the bits in the CItE range
>  (21-26) is one or there is a critical feature invoked in some further

"...if any of the bits... are one or..."
(replace "is" with "are")



>  The first three have the same meaning as the corresponding ECN field
>  codepoints in the IPv4 or IPv6 header as defined in [RFC3168].

Section 1.1 defines "IP" to mean both IPv4 and IPv6. It would seem cleaner and
easier to read if the document were to leverage that definition here.


>  However codepoint 0b11 is called Non-Critical Congestion Experienced

"However, codepoint..."
(insert comma)

---------------------------------------------------------------------------

§3.3.2:

>  If an RBridge supports ECN, for the two cases of an IP and a non-IPR

"...non-IP"

---------------------------------------------------------------------------

§4:

>  Section 3 specifies interworking between TRILL and the original
>  standardized form of ECN in IP [RFC3168].

Please indicate this at the top of Section 3. When I was puzzling over Table 3,
I spent some time trying to figure out whether the behavior I describe in my
DISCUSS above was due to behavior described in RFC 8311 or the experiments it
contemplates.

---------------------------------------------------------------------------

Appendix A:

>  o  the meaning of CE markings applied by an L4S queue is not the same
>    as the meaning of a drop by a "Classic" queue (contrary to the
>    original requirement for ECN [RFC3168]).

I think, when citing this exception, it makes much more sense to point to RFC
8311
(where the exception to RFC 3168's requirement is defined) than to RFC 3168
in a vacuum.

>    Instead the likelihood

Insert a comma after "Instead".

>    that the Classic queue drops packets is defined as the square of
>    the likelihood that the L4S queue marks packets (e.g. when there

Insert a comma after "e.g.,"
2018-02-20
05 Adam Roach [Ballot Position Update] Position for Adam Roach has been changed to No Objection from Discuss
2018-02-16
05 Tero Kivinen Closed request for Last Call review by SECDIR with state 'No Response'
2018-02-08
05 Cindy Morgan IESG state changed to IESG Evaluation::Revised I-D Needed from Waiting for Writeup
2018-02-08
05 Alexey Melnikov [Ballot Position Update] New position, No Objection, has been recorded for Alexey Melnikov
2018-02-07
05 Adam Roach
[Ballot discuss]
Thanks to the authors, chairs, shepherd, and working group for the effort that
has been put into this document.

I have concerns about …
[Ballot discuss]
Thanks to the authors, chairs, shepherd, and working group for the effort that
has been put into this document.

I have concerns about some ambiguity and/or self-contradiction in this
specification, but I suspect these should be easy to fix. In particular, the
behavior defined in Table 3 doesn't seem to be consistent with the behavior
described in the prose.

For easy reference, I've copied Table 3 here:

>      +---------+----------------------------------------------+
>      | Inner  |  Arriving TRILL 3-bit ECN Codepoint Name    |
>      | Native  +---------+------------+------------+----------+
>      | Header  | Not-ECT | ECT(0)    | ECT(1)    |    CE  |
>      +---------+---------+------------+------------+----------+
>      | Not-ECT | Not-ECT | Not-ECT(*) | Not-ECT(*) |    |
>      |  ECT(0) |  ECT(0) |  ECT(0)    |  ECT(1)    |    CE  |
>      |  ECT(1) |  ECT(1) |  ECT(1)(*) |  ECT(1)    |    CE  |
>      |    CE  |      CE |      CE    |      CE(*) |    CE  |
>      +---------+---------+------------+------------+----------+
>
>                      Table 3. Egress ECN Behavior
>
>  An asterisk in the above table indicates a currently unused
>  combination that SHOULD be logged. In contrast to [RFC6040], in TRILL
>  the drop condition is the result of a valid combination of events and
>  need not be logged.

The prose in this document indicates:

1. Ingress gateway either copies the native header value to the TRILL ECN
    codepoint (resulting in any of the four values above) or doesn't insert
    any ECN information in the TRILL header.

2. Intermediate gateways can set the CCE flag, resulting in "CE" in the
    table above.

Based on the above, a packet arriving at an egress gateway can only be in one of
the following states:

A. TRILL header is Not-ECT because no TRILL node inserted ECN information.

B. TRILL header value == Native header value because the ingress gateway
    copied it from native to TRILL.

C. TRILL header is "CE" because an intermediate node indicated congestion.

If that's correct, I would think that any state other than those three needs
to be marked with an (*). In particular, these two states fall into that
classification, and seem to require an asterisk:

  - Native==CE && TRILL==ECT(0)

  - Native==ECT(0) && TRILL==ECT(1)

In addition, the behavior this table defines for Native==ECT(0) && TRILL==ECT(1)
is somewhat perplexing: for this case, the value in the TRILL header takes
precedence; however, when Native==ECT(1) && TRILL==ECT(0) the Native header
takes precedence. Or, put another way, this table defines ECT(1) to always
override ECT(0). I don't find any prose in here to indicate why this needs to be
treated differentially, so I'm left to conclude that this is a typographical
error. If that's not the case, please add motivating text to Table 3 explaining
why ECT(1) is treated differently than ECT(0) for baseline ECN behavior.
2018-02-07
05 Adam Roach
[Ballot comment]
I also have a small handful of editorial suggestions and nits to propose.

Please expand "TRILL" upon first use and in the title; …
[Ballot comment]
I also have a small handful of editorial suggestions and nits to propose.

Please expand "TRILL" upon first use and in the title; see
https://www.rfc-editor.org/materials/abbrev.expansion.txt for guidance.

---------------------------------------------------------------------------
§1:

>  In [RFC3168] it was recognized that tunnels and lower layer protocols

"In [RFC3168], it was..."
(insert comma)

---------------------------------------------------------------------------

§2:

>  These fields are show in Figure 2 as "ECN" and "CCE". The TRILL-ECN

"...are shown..."


>  The CRItE bit is the critical Ingress-to-Egress summary
>  bit and will be one if and only if any of the bits in the CItE range
>  (21-26) is one or there is a critical feature invoked in some further

"...if any of the bits... are one or..."
(replace "is" with "are")



>  The first three have the same meaning as the corresponding ECN field
>  codepoints in the IPv4 or IPv6 header as defined in [RFC3168].

Section 1.1 defines "IP" to mean both IPv4 and IPv6. It would seem cleaner and
easier to read if the document were to leverage that definition here.


>  However codepoint 0b11 is called Non-Critical Congestion Experienced

"However, codepoint..."
(insert comma)

---------------------------------------------------------------------------

§3.3.2:

>  If an RBridge supports ECN, for the two cases of an IP and a non-IPR

"...non-IP"

---------------------------------------------------------------------------

§4:

>  Section 3 specifies interworking between TRILL and the original
>  standardized form of ECN in IP [RFC3168].

Please indicate this at the top of Section 3. When I was puzzling over Table 3,
I spent some time trying to figure out whether the behavior I describe in my
DISCUSS above was due to behavior described in RFC 8311 or the experiments it
contemplates.

---------------------------------------------------------------------------

Appendix A:

>  o  the meaning of CE markings applied by an L4S queue is not the same
>    as the meaning of a drop by a "Classic" queue (contrary to the
>    original requirement for ECN [RFC3168]).

I think, when citing this exception, it makes much more sense to point to RFC
8311
(where the exception to RFC 3168's requirement is defined) than to RFC 3168
in a vacuum.

>    Instead the likelihood

Insert a comma after "Instead".

>    that the Classic queue drops packets is defined as the square of
>    the likelihood that the L4S queue marks packets (e.g. when there

Insert a comma after "e.g.,"
2018-02-07
05 Adam Roach [Ballot Position Update] New position, Discuss, has been recorded for Adam Roach
2018-02-07
05 Suresh Krishnan [Ballot Position Update] New position, No Objection, has been recorded for Suresh Krishnan
2018-02-07
05 Terry Manderson [Ballot Position Update] New position, No Objection, has been recorded for Terry Manderson
2018-02-07
05 Amanda Baber IANA Review state changed to IANA OK - Actions Needed from Version Changed - Review Needed
2018-02-07
05 Ben Campbell [Ballot comment]
Just a typo in section 6: s/  significnat / significant

(And I see Spencer already caught it :-) )
2018-02-07
05 Ben Campbell Ballot comment text updated for Ben Campbell
2018-02-07
05 Ben Campbell [Ballot comment]
Just a typo in section 6: s/  significnat / significant
2018-02-07
05 Ben Campbell [Ballot Position Update] New position, No Objection, has been recorded for Ben Campbell
2018-02-07
05 Kathleen Moriarty [Ballot Position Update] New position, No Objection, has been recorded for Kathleen Moriarty
2018-02-07
05 Alissa Cooper [Ballot Position Update] New position, No Objection, has been recorded for Alissa Cooper
2018-02-07
05 Spencer Dawkins
[Ballot comment]
I agree with Mirja about the status of L4S, but would go even farther - L4S is only one of the ECN experiments …
[Ballot comment]
I agree with Mirja about the status of L4S, but would go even farther - L4S is only one of the ECN experiments that https://datatracker.ietf.org/doc/rfc8311/ was intended to accommodate, so you might want to capture that in the appendix (basically saying "L4S is one example of the ways TRILL ECN handling may evolve", or something like that).

Is

  If an RBridge supports ECN, for the two cases of an IP and a non-IPR
  inner packet, the egress behavior is as follows:

really "non-IPR"? I'm guessing it should be "non-IP".

s/significnat/significant/
2018-02-07
05 Spencer Dawkins [Ballot Position Update] New position, Yes, has been recorded for Spencer Dawkins
2018-02-07
05 Benoît Claise [Ballot Position Update] New position, No Objection, has been recorded for Benoit Claise
2018-02-07
05 Deborah Brungard [Ballot Position Update] New position, No Objection, has been recorded for Deborah Brungard
2018-02-07
05 Alvaro Retana [Ballot Position Update] New position, No Objection, has been recorded for Alvaro Retana
2018-02-07
05 Mirja Kühlewind
[Ballot comment]
Given L4S is not published yet and in any case experimental, I would recommend to remove section 4.2 entirely and just keep the …
[Ballot comment]
Given L4S is not published yet and in any case experimental, I would recommend to remove section 4.2 entirely and just keep the appendix as an informational documentation of the proposed alogrithm.
2018-02-07
05 Mirja Kühlewind [Ballot Position Update] New position, No Objection, has been recorded for Mirja Kühlewind
2018-02-06
05 Eric Rescorla [Ballot Position Update] New position, No Objection, has been recorded for Eric Rescorla
2018-02-06
05 Alia Atlas Ballot has been issued
2018-02-06
05 Alia Atlas [Ballot Position Update] New position, Yes, has been recorded for Alia Atlas
2018-02-06
05 Alia Atlas Created "Approve" ballot
2018-02-06
05 Alia Atlas Ballot writeup was changed
2018-02-05
05 Sarah Banks Request for Last Call review by OPSDIR Completed: Has Nits. Reviewer: Sarah Banks. Sent review to list.
2018-02-05
05 (System) IESG state changed to Waiting for Writeup from In Last Call
2018-02-04
05 (System) IANA Review state changed to Version Changed - Review Needed from IANA OK - Actions Needed
2018-02-04
05 Donald Eastlake New version available: draft-ietf-trill-ecn-support-05.txt
2018-02-04
05 (System) New version approved
2018-02-04
05 (System) Request for posting confirmation emailed to previous authors: Bob Briscoe , Donald Eastlake
2018-02-04
05 Donald Eastlake Uploaded new revision
2018-02-04
04 Michael Tüxen Request for Last Call review by TSVART Completed: Ready with Nits. Reviewer: Michael Tüxen. Sent review to list.
2018-02-04
04 Dan Romascanu Request for Last Call review by GENART Completed: Ready. Reviewer: Dan Romascanu. Sent review to list.
2018-01-31
04 (System) IANA Review state changed to IANA OK - Actions Needed from IANA - Review Needed
2018-01-31
04 Sabrina Tanamal
(Via drafts-lastcall@iana.org): IESG/Authors/WG Chairs:

The IANA Services Operator has completed its review of draft-ietf-trill-ecn-support-04. If any part of this review is inaccurate, please let …
(Via drafts-lastcall@iana.org): IESG/Authors/WG Chairs:

The IANA Services Operator has completed its review of draft-ietf-trill-ecn-support-04. If any part of this review is inaccurate, please let us know.

The IANA Services Operator understands that, upon approval of this document, there is a single action which we must complete.

In the TRILL Extended Header Flags registry on the Transparent Interconnection of Lots of Links (TRILL) Parameters registry page located at:

https://www.iana.org/assignments/trill-parameters/

The existing entry for bits 9-13 is currently:

Bits Purpose Reference
-------+---------------------------------------------+--------------
9-13 available non-critical hop-by-hop flags [RFC7179]

It will be changed to the following two lines:

Bits Purpose Reference
-------+---------------------------------------------+--------------
9-11 available non-critical hop-by-hop flags [RFC7179]
12-13 TRILL-ECN (Explicit Congestion Notification) [ RFC-to-be ]

The existing entry for bits 21-26 is currently:

Bits Purpose Reference
-------+---------------------------------------------+--------------
21-26 available critical ingress-to-egress flag [RFC7179]

This will be changed to:

Bits Purpose Reference
-------+---------------------------------------------+--------------
21-25 available critical ingress-to-egress flag [RFC7179]
26 Critical Congestion Experienced (CCE) [ RFC-to-be ]

The IANA Services Operator understands that this is the only action 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 the list of actions that will be performed.


Thank you,

Sabrina Tanamal
Senior IANA Services Specialist
2018-01-25
04 Tero Kivinen Request for Last Call review by SECDIR is assigned to Steve Hanna
2018-01-25
04 Tero Kivinen Request for Last Call review by SECDIR is assigned to Steve Hanna
2018-01-25
04 Jean Mahoney Request for Last Call review by GENART is assigned to Dan Romascanu
2018-01-25
04 Jean Mahoney Request for Last Call review by GENART is assigned to Dan Romascanu
2018-01-25
04 Gunter Van de Velde Request for Last Call review by OPSDIR is assigned to Sarah Banks
2018-01-25
04 Gunter Van de Velde Request for Last Call review by OPSDIR is assigned to Sarah Banks
2018-01-23
04 Martin Stiemerling Request for Last Call review by TSVART is assigned to Michael Tüxen
2018-01-23
04 Martin Stiemerling Request for Last Call review by TSVART is assigned to Michael Tüxen
2018-01-22
04 Cindy Morgan IANA Review state changed to IANA - Review Needed
2018-01-22
04 Cindy Morgan
The following Last Call announcement was sent out (ends 2018-02-05):

From: The IESG
To: IETF-Announce
CC: Susan Hares , akatlas@gmail.com, trill-chairs@ietf.org, trill@ietf.org, …
The following Last Call announcement was sent out (ends 2018-02-05):

From: The IESG
To: IETF-Announce
CC: Susan Hares , akatlas@gmail.com, trill-chairs@ietf.org, trill@ietf.org, draft-ietf-trill-ecn-support@ietf.org, shares@ndzh.com
Reply-To: ietf@ietf.org
Sender:
Subject: Last Call:  (TRILL: ECN (Explicit Congestion Notification) Support) to Proposed Standard


The IESG has received a request from the Transparent Interconnection of Lots
of Links WG (trill) to consider the following document: - 'TRILL: ECN
(Explicit Congestion Notification) Support'
  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 2018-02-05. 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


  Explicit congestion notification (ECN) allows a forwarding element to
  notify downstream devices, including the destination, of the onset of
  congestion without having to drop packets. This can improve network
  efficiency through better flow control without packet drops. This
  document extends ECN to TRILL switches, including integration with IP
  ECN, and provides for ECN marking in the TRILL Header Extension Flags
  Word (see RFC 7179).





The file can be obtained via
https://datatracker.ietf.org/doc/draft-ietf-trill-ecn-support/

IESG discussion can be tracked via
https://datatracker.ietf.org/doc/draft-ietf-trill-ecn-support/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-tsvwg-ecn-encap-guidelines: Guidelines for Adding Congestion Notification to Protocols that Encapsulate IP (None - IETF stream)



2018-01-22
04 Cindy Morgan IESG state changed to In Last Call from Last Call Requested
2018-01-22
04 Alia Atlas Placed on agenda for telechat - 2018-02-08
2018-01-22
04 Alia Atlas Last call was requested
2018-01-22
04 Alia Atlas Last call announcement was generated
2018-01-22
04 Alia Atlas Ballot approval text was generated
2018-01-22
04 Alia Atlas Ballot writeup was generated
2018-01-22
04 Alia Atlas IESG state changed to Last Call Requested from AD Evaluation
2018-01-22
04 Alia Atlas IESG state changed to AD Evaluation from Publication Requested
2018-01-22
04 Susan Hares
(1) What type of RFC is being requested (BCP, Proposed Standard,
    Internet Standard, Informational, Experimental, or Historic)? Why
    is this the …
(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 status is requested as indicated on the title
page. This document modifies the TRILL protocol by specifying, with
backward compatibility, the use of previously reserved TRILL Header
bits.

(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 specification provides for any Explicit Congestion Notification
(ECN) marking in traffic ingressed by TRILL to be copied into the
TRILL Extension Header Flags Word [RFC7179]. It also enables
congestion marking by a congested transit TRILL switch in the TRILL
Header Extension Flags Word.  At TRILL egress, it specifies how any
ECN markings in the TRILL Header Flags Word and in the encapsulated
traffic are combined so that subsequent forwarding elements can see if
congestion was experienced at any previous point in the path from the
Source.

  Working Group Summary:

There was no particular controversy about this document. Although some
minor technical refinements were made during the WG process, the WG
appears to have been favorably disposed towards this work from the
beginning.

  Document Quality:

No implementations of draft-ietf-trill-ecn-support-03.
Document has been reviewed by RTG-DIR (QA review).

  Personnel:
    Document Shepherd: Susan Hares
    Responsible Area Director: Alia Atlas
      RTG-DIR review: Loa Anderson
Review 1:
https://datatracker.ietf.org/doc/review-ietf-trill-ecn-support-01-rtgdir-early-andersson-2017-01-21/
Review 2:
https://datatracker.ietf.org/doc/review-ietf-trill-ecn-support-03-rtgdir-early-andersson-2017-06-19/

Shepherd's report
https://mailarchive.ietf.org/arch/msg/trill/8L-hgWSUw4zrWyAq3MbSOlg8iI8

(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.

  Document has been reviewed for technical content against normative references.
  (see shepherd's report email
https://mailarchive.ietf.org/arch/msg/trill/8L-hgWSUw4zrWyAq3MbSOlg8iI8).

  ID-NITS have been, and the only nits is that the copyright year is 2015.
  The shepherd has been backlogged with other work, and did not
  get this reviewed promptly in December.  The first editorial revision from the
  AD or the IESG will fix it.

(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 of this document.

(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.

Normal reviews for routing draft (rtg-dir, ops-dir, sec-dir)
and any reviews AD feels is necessary for INT ECN.

(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 particular concernts.

(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
  Bob Biscoe
https://www.ietf.org/mail-archive/web/trill/current/msg07790.html
  Donald Eastlake
https://www.ietf.org/mail-archive/web/trill/current/msg07789.html

(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 against this document.

(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?

WG had good initial discussions, and strong concurrent on technology.

(10) Has anyone threatened an appeal or otherwise indicated extreme
    discontent?

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.

Only ID nit complaint is that it noticed some pseudo-code and
suggested it might be bracketed with and
lines but this seems inappropriate for psuedo-code that is not
intended to be compiled.    will also
trigger YANG automatic review - which would be a mistake.

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

No such formal review 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?

There is a normative reference to
draft-ietf-tsvwg-ecn-encap-guidelines which is intended to be a Best
Current Practice.

(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 downward references.

(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.

This document does not change the status of any existing RFC.

(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.

The only IANA action required by this document is the allocation of
three bits in the TRILL Extended Header Flags for which a registry
already exists. This is clearly indicated in the IANA Considerations
section.

(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.

No new registries created.

(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.

Although there is a little pseudo-code, there is no mormal language
requiring validation in this document.
2018-01-22
04 Susan Hares Responsible AD changed to Alia Atlas
2018-01-22
04 Susan Hares IETF WG state changed to Submitted to IESG for Publication from WG Consensus: Waiting for Write-Up
2018-01-22
04 Susan Hares IESG state changed to Publication Requested
2018-01-22
04 Susan Hares IESG process started in state Publication Requested
2018-01-22
04 Susan Hares Changed document writeup
2018-01-14
04 Donald Eastlake Changed document writeup
2017-11-20
04 Donald Eastlake New version available: draft-ietf-trill-ecn-support-04.txt
2017-11-20
04 (System) New version approved
2017-11-20
04 (System) Request for posting confirmation emailed to previous authors: Bob Briscoe , Donald Eastlake
2017-11-20
04 Donald Eastlake Uploaded new revision
2017-11-11
03 Susan Hares Changed document writeup
2017-10-26
03 Donald Eastlake Changed document writeup
2017-09-27
03 Susan Hares IETF WG state changed to WG Consensus: Waiting for Write-Up from In WG Last Call
2017-06-19
03 Min Ye Request for Early review by RTGDIR Completed: Ready. Reviewer: Loa Andersson.
2017-05-31
03 Min Ye Request for Early review by RTGDIR is assigned to Loa Andersson
2017-05-31
03 Min Ye Request for Early review by RTGDIR is assigned to Loa Andersson
2017-05-31
03 Susan Hares IETF WG state changed to In WG Last Call from WG Document
2017-05-31
03 Susan Hares Requested Early review by RTGDIR
2017-05-28
03 Donald Eastlake New version available: draft-ietf-trill-ecn-support-03.txt
2017-05-28
03 (System) New version approved
2017-05-28
03 (System) Request for posting confirmation emailed to previous authors: trill-chairs@ietf.org, Bob Briscoe , Donald Eastlake
2017-05-28
03 Donald Eastlake Uploaded new revision
2017-03-12
02 Donald Eastlake New version available: draft-ietf-trill-ecn-support-02.txt
2017-03-12
02 (System) New version approved
2017-03-12
02 (System) Request for posting confirmation emailed to previous authors: trill-chairs@ietf.org, Bob Briscoe , Donald Eastlake
2017-03-12
02 Donald Eastlake Uploaded new revision
2017-01-21
01 Min Ye Request for Early review by RTGDIR Completed: Has Issues. Reviewer: Loa Andersson.
2017-01-15
01 Min Ye Request for Early review by RTGDIR is assigned to Loa Andersson
2017-01-15
01 Min Ye Request for Early review by RTGDIR is assigned to Loa Andersson
2017-01-14
01 Susan Hares Requested Early review by RTGDIR
2016-10-28
01 Donald Eastlake New version available: draft-ietf-trill-ecn-support-01.txt
2016-10-28
01 (System) New version approved
2016-10-28
00 (System) Request for posting confirmation emailed to previous authors: "Donald Eastlake" , trill-chairs@ietf.org, "Bob Briscoe"
2016-10-28
00 Donald Eastlake Uploaded new revision
2016-10-21
00 Donald Eastlake Notification list changed to "Susan Hares" <shares@ndzh.com>
2016-10-21
00 Donald Eastlake Document shepherd changed to Susan Hares
2016-10-21
00 Donald Eastlake Changed consensus to Yes from Unknown
2016-10-21
00 Donald Eastlake Intended Status changed to Proposed Standard from None
2016-10-21
00 Donald Eastlake This document now replaces draft-eastlake-trill-ecn-support instead of None
2016-10-19
00 Donald Eastlake New version available: draft-ietf-trill-ecn-support-00.txt
2016-10-19
00 (System) New version approved
2016-10-19
00 Donald Eastlake Request for posting confirmation emailed  to submitter and authors: "Donald E. Eastlake" , "Bob Briscoe"
2016-10-19
00 Donald Eastlake Uploaded new revision