Multihoming Deployment Considerations for DDoS Open Threat Signaling (DOTS)
draft-ietf-dots-multihoming-13

[Ballot comment]
Understood that the multihoming is talking about the edge router itself and not hosts within the next.

Agreed this is simpler and not necessary to complicate the document.

Thanks.

[Ballot comment]
DISCUSS item and comments resolved

[1]
  The DOTS client SHOULD use the certificate
  provided by a provisioning domain to authenticate itself to the DOTS
  server(s) provided by the same provisioning domain.

This sentence suggests there is either another authentication method, or it allows for unauthenticated DOTS clients. If the latter, than I would expect a significant Security Considerations section on how to avoid/reduce malicious clients impact of such a setup. eg I could envision a compromised device from falsely reporting a DDOS attack from a certain network to block the compromised device/network from receiving traffic from certain remote networks.


Some links seem broken in the rendering of the htmlized version in the datatracker, for example "[RFC8174]" in Section 2.

It talks about DOTS clients, DOTS servers, and then suddenly DOTS agents. Are those clients or servers or something else? "agents" are not mentioned in the Introduction or Terminology sections. (Unfortunately, looking at RFC 8811 did not help me as it has the exact same problem of only defining DOTS clients and DOTS servers and then mentioning DOTS agents.

Similarly, the term "DOTS Gateway" appears without explanation. Is this a proxy like DOTS server for clients and a DOTS client to the real DOTS server?

I'm a bit confused about the applicability of the enduser CPE case. Wouldn't a lot of deployments have the CPE in bridging mode so that the customers own favourite device gets the actual IP address on it instead of being behind the CPE with NAT? Is there a deployment scenario possible for that?

I would move Figure 5 up to the start of the section. I now had to scroll down a lot and then back up again, and then when done reading had to skip the figure 5.

  If PI addresses/prefixes are in use, the DOTS client MUST send a
  mitigation request to all the DOTS servers.  The use of anycast
  addresses to reach these DOTS servers is NOT RECOMMENDED.

Why is the recommendation about anycast addresses limited to PI space? Couldn't there by multicast addresses in both PA and PI space?

  a prefix filter that will be against DDoS detection alarms

I don't quite parse/understand "will be against" ?

[Ballot comment]
DISCUSS item resolved:

[1]
  The DOTS client SHOULD use the certificate
  provided by a provisioning domain to authenticate itself to the DOTS
  server(s) provided by the same provisioning domain.

This sentence suggests there is either another authentication method, or it allows for unauthenticated DOTS clients. If the latter, than I would expect a significant Security Considerations section on how to avoid/reduce malicious clients impact of such a setup. eg I could envision a compromised device from falsely reporting a DDOS attack from a certain network to block the compromised device/network from receiving traffic from certain remote networks.


Some links seem broken in the rendering of the htmlized version in the datatracker, for example "[RFC8174]" in Section 2.

It talks about DOTS clients, DOTS servers, and then suddenly DOTS agents. Are those clients or servers or something else? "agents" are not mentioned in the Introduction or Terminology sections. (Unfortunately, looking at RFC 8811 did not help me as it has the exact same problem of only defining DOTS clients and DOTS servers and then mentioning DOTS agents.

Similarly, the term "DOTS Gateway" appears without explanation. Is this a proxy like DOTS server for clients and a DOTS client to the real DOTS server?

I'm a bit confused about the applicability of the enduser CPE case. Wouldn't a lot of deployments have the CPE in bridging mode so that the customers own favourite device gets the actual IP address on it instead of being behind the CPE with NAT? Is there a deployment scenario possible for that?

I would move Figure 5 up to the start of the section. I now had to scroll down a lot and then back up again, and then when done reading had to skip the figure 5.

  If PI addresses/prefixes are in use, the DOTS client MUST send a
  mitigation request to all the DOTS servers.  The use of anycast
  addresses to reach these DOTS servers is NOT RECOMMENDED.

Why is the recommendation about anycast addresses limited to PI space? Couldn't there by multicast addresses in both PA and PI space?

  a prefix filter that will be against DDoS detection alarms

I don't quite parse/understand "will be against" ?

[Ballot comment]
Thank you for the work put into this document: it is short, easy to read.

Please find below some non-blocking COMMENT points (but replies would be appreciated even if only for my own education).

Special thanks to Valery Smyslov for the shepherd's write-up including the WG consensus (including "not too many reviews") *BUT* it lacks the justification of the intended status.

Authors may also expect an internet directorate review by Dave Thaler, the delay in the review (caused by late addition of this document to the telechat agenda) should not hinder the publication process though.

I also second Erik Kline's DISCUSS about source address selection.

I hope that this helps to improve the document,

Regards,

-éric

Note for the shepherding AD: missing consensus boilerplate.

## Section 4.2

Suggest to state the obvious in bullet 2, i.e., that addresses from one PvD is used when communicating over this PvD (to be symmetric with bullet 1). This is purely cosmetic.

## Section 4.3

Another cosmetic suggestion: please use CPE1 and CPE2, again for symmetry.

## Section 5.1

I am always uneasy when I read normative MUST / SHOULD in an informational document but the authors may ignore this comment.

There is a "SHOULD use the certificate" without specifying when the SHOULD does not apply.

## Section 5.2

Another cosmetic comment, the graphical convention of figures 7 & 8 (i.e., having the DOTS clients in a central dotted box) should also be used in figure 6.

[Ballot discuss]
## Discuss

### S5.1

* RFC 6724 source address selection is not sufficient.  Many complexities
  are captured in RFC 8678.  As RFC 8475 notes, what's really required to
  make this work for some nodes is proper next-hop selection in conjunction
  with source address selection.  Either that, or some kind of source-aware
  routing for forwarding nodes.

  For originating packets, depending on the topology, the following options
  can in theory be made to work:

    * implementing RFC 6724 rule 5.5, but it's not currently mandatory

    * implementing RFC 6724 section 4 recommendation "that the candidate
      source addresses be the set of unicast addresses assigned to the
      interface that will be used to send to the destination (the "outgoing"
      interface)" -- but this is highly dependent upon interface config

    * use of PVD Options (RFC 8801) throughout the interior (and, ideally, an
      IETF-defined PVD End System model)

  I'm don't think that it's worth going into all this detail in this document,
  necessarily.  You might see if a mix of references to and/or quotations from
  8678, 8475, and/or mention of the issue of next-hop selection in conjunction
  with source address selection yields sufficiently concise text to warn the
  IPv6-multihoming-unfamiliar reader: "here be dragons (hic sunt dracones)".

[Ballot discuss]
Thanks for a clear document and thanks to Kathleen for the SecDir review. I have one minor DISCUSS item that can probably be resolved easily by adding a sentence or two.


[1]
  The DOTS client SHOULD use the certificate
  provided by a provisioning domain to authenticate itself to the DOTS
  server(s) provided by the same provisioning domain.

This sentence suggests there is either another authentication method, or it allows for unauthenticated DOTS clients. If the latter, than I would expect a significant Security Considerations section on how to avoid/reduce malicious clients impact of such a setup. eg I could envision a compromised device from falsely reporting a DDOS attack from a certain network to block the compromised device/network from receiving traffic from certain remote networks.

[Ballot comment]
Some links seem broken in the rendering of the htmlized version in the datatracker, for example "[RFC8174]" in Section 2.

It talks about DOTS clients, DOTS servers, and then suddenly DOTS agents. Are those clients or servers or something else? "agents" are not mentioned in the Introduction or Terminology sections. (Unfortunately, looking at RFC 8811 did not help me as it has the exact same problem of only defining DOTS clients and DOTS servers and then mentioning DOTS agents.

Similarly, the term "DOTS Gateway" appears without explanation. Is this a proxy like DOTS server for clients and a DOTS client to the real DOTS server?

I'm a bit confused about the applicability of the enduser CPE case. Wouldn't a lot of deployments have the CPE in bridging mode so that the customers own favourite device gets the actual IP address on it instead of being behind the CPE with NAT? Is there a deployment scenario possible for that?

I would move Figure 5 up to the start of the section. I now had to scroll down a lot and then back up again, and then when done reading had to skip the figure 5.

  If PI addresses/prefixes are in use, the DOTS client MUST send a
  mitigation request to all the DOTS servers.  The use of anycast
  addresses to reach these DOTS servers is NOT RECOMMENDED.

Why is the recommendation about anycast addresses limited to PI space? Couldn't there by multicast addresses in both PA and PI space?

  a prefix filter that will be against DDoS detection alarms

I don't quite parse/understand "will be against" ?

[Ballot comment]
Hi,

Thanks for this document.

Two comments on section 5.1:

1.
  The DOTS client MUST resolve the DOTS server's name provided by each
  provisioning domain using either the DNS servers learned from the
  respective provisioning domain or from the DNS servers associated
  with the interface(s) for which a DOTS server was explicitly
  configured (Section 4).

It wasn't clear to me why the DNS lookup MUST be done relative to each provisioning domain?

2.
  DOTS signaling
  session to a given DOTS server must be established using the
  interface from which the DOTS server was provisioned.

If I have read and understood the draft correctly that it also seems that requests to ask a DOTS server to mitigate an attack must also be done on the same interface on which that attack is occurring.  Is my understanding correct, and if so, why is this a requirement?  I.e., communicating to a DOTS server via a separate link that isn't under attack would seem to be beneficial (when that is possible).  Is the reasoning here that these are stub networks and hence will only be routable via the interface provided by the ISP's gateway?

Regards,
Rob

[Ballot comment]
Section 4, paragraph 1, comment:
> 4.  Multi-Homing Scenarios

I'm surprised to not see this section referring to any of the MULTI6 documents.
It's been a while since I read them, but IIRC, they dealt with many of these
scenarios and gave similar recommendations.

The datatracker state does not indicate whether the consensus boilerplate
should be included in this document.

Found terminology that should be reviewed for inclusivity; see
https://www.rfc-editor.org/part2/#inclusive_language for background and more
guidance:

* Term "blindly"; alternatives might be "visually impaired", "unmindful of",
  "unconcerned about", "negligent of", "unaware", "uncomprehending",
  "unaware", "uncritical", "unthinking", "hasty", "blocked", "opaque"

[Ballot comment]
Thanks for working on this specification. Thanks to Mirja Kuhlewind for the TSVART review.

I agree with the my fellow TSV AD and TSVART reviewer that no TSV related issue is found in this specification.

[Ballot comment]
Thanks to Mirja Kuhlewind for the TSVART review.

There is nothing at all wrong with this document, but it is not what I expected. IIUC DOTS will often have different interfaces for its DOTS channel and the "data plane" where DoS attacks come in. I had thought the multihoming reference would refer to that, but it does not.

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

The IANA Functions Operator has reviewed draft-ietf-dots-multihoming-11, which is currently in Last Call, and has the following comments:

We understand that this document doesn't require any registry actions.

While it's often helpful for a document's IANA Considerations section to remain in place upon publication even if there are no actions, if the authors strongly prefer to remove it, we do not object.

If this assessment is not accurate, please respond as soon as possible.

Thank you,

Michelle Thangtamsatid
IANA Services Specialist

The following Last Call announcement was sent out (ends 2022-04-04):

From: The IESG
To: IETF-Announce
CC: dots-chairs@ietf.org, dots@ietf.org, draft-ietf-dots-multihoming@ietf.org, rdd@cert.org, valery@smyslov.net
Reply-To: last-call@ietf.org
Sender:
Subject: Last Call:  (Multi-homing Deployment Considerations for Distributed-Denial-of-Service Open Threat Signaling (DOTS)) to Informational RFC


The IESG has received a request from the DDoS Open Threat Signaling WG (dots)
to consider the following document: - 'Multi-homing Deployment Considerations
for Distributed-Denial-of-
  Service Open Threat Signaling (DOTS)'
  as Informational RFC

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
last-call@ietf.org mailing lists by 2022-04-04. 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


  This document discusses multi-homing considerations for Distributed-
  Denial-of-Service Open Threat Signaling (DOTS).  The goal is to
  provide some guidance for DOTS clients and client-domain DOTS
  gateways when multihomed.




The file can be obtained via
https://datatracker.ietf.org/doc/draft-ietf-dots-multihoming/



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

(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? 

  Informational as indicated on the title page header and in the datatracker.

(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 discusses multi-homing considerations for Distributed-
  Denial-of-Service Open Threat Signaling (DOTS). The goal is to
  provide some guidance for DOTS clients and client-domain DOTS
  gateways when multihomed.

Working Group Summary:

  The first version of the document was published as individual draft in June 2017.
  The draft was adopted as WG document in January 2019, but received little
  attention from WG members until the fall of 2021, since the WG was busy with more urgent
  documents. The situation started changing after the WGLC for the document was issued
  and early reviews were requested, so that afterall the draft has been sufficiently discussed
  (with some definition of "sufficiently").

Document Quality:

  Document authors are also co-authors of core DOTS documents (signal channel, data channel etc.)
  To my best knowledge there is at least one implementation that follows guidelines from the document.

Personnel:

  Valery Smyslov (shepherd)
  Benjamin Kaduk (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 the document and found it ready.

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

  No. The document was a subject of reviews in the WG and by external experts (OPSDIR, SECDIR).

(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. 

  Early Reviews have been performed by Ops and Security Directorates.
  I personally don't think that more reviews are needed.

(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. 

  None.

(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?

  All authors and contributors confirmed that they are not aware of any IPR related to this draft.

  ** Mohamed Boucadair -- https://mailarchive.ietf.org/arch/msg/dots/snqL2m4aFISAk9ttDDqiGNCy2T8/
  ** Tirumaleswar Reddy -- https://mailarchive.ietf.org/arch/msg/dots/xx9dPak-0dX9SuR1QqlPbeJlZSQ/
  ** Pan Wei -- https://mailarchive.ietf.org/arch/msg/dots/uqndoqiklmiG_wMInsESm9H7UGc/

(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 that reference 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? 

  The WG consensus is solid.

(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. 

  No ID nits were found by idnits tool.

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

  None are applicable.

(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 8126). 

  The document contains no requests to 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. 

  No new registries are defined by this document.

(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.

  No automated checks are applicable.

(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?

  The document contains no YANG module.

(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? 

  Informational as indicated on the title page header and in the datatracker.

(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 discusses multi-homing considerations for Distributed-
  Denial-of-Service Open Threat Signaling (DOTS). The goal is to
  provide some guidance for DOTS clients and client-domain DOTS
  gateways when multihomed.

Working Group Summary:

  The first version of the document was published as individual draft in June 2017.
  The draft was adopted as WG document in January 2019, but received little
  attention from WG members until the fall of 2021, since the WG was busy with more urgent
  documents. The situation started changing after the WGLC for the document was issued
  and early reviews were requested, so that afterall the draft has been sufficiently discussed
  (with some definition of "sufficiently").

Document Quality:

  Document authors are also co-authors of core DOTS documents (signal channel, data channel etc.)
  To my best knowledge there is at least one implementation that follows guidelines from the document.

Personnel:

  Valery Smyslov (shepherd)
  Benjamin Kaduk (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 the document and found it ready.

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

  No. The document was a subject of reviews in the WG and by external experts (OPSDIR, SECDIR).

(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. 

  Early Reviews have been performed by Ops and Security Directorates.
  I personally don't think that more reviews are needed.

(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. 

  None.

(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?

  All authors and contributors confirmed that they are not aware of any IPR related to this draft.

  ** Mohamed Boucadair -- https://mailarchive.ietf.org/arch/msg/dots/snqL2m4aFISAk9ttDDqiGNCy2T8/
  ** Tirumaleswar Reddy -- https://mailarchive.ietf.org/arch/msg/dots/xx9dPak-0dX9SuR1QqlPbeJlZSQ/
  ** Pan Wei -- https://mailarchive.ietf.org/arch/msg/dots/uqndoqiklmiG_wMInsESm9H7UGc/

(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 that reference 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? 

  The WG consensus is solid.

(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. 

  No ID nits were found by idnits tool.

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

  None are applicable.

(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 8126). 

  The document contains no requests to 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. 

  No new registries are defined by this document.

(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.

  No automated checks are applicable.

(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?

  The document contains no YANG module.

(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? 

  Informational as indicated on the title page header and in the datatracker.

(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 discusses multi-homing considerations for Distributed-
  Denial-of-Service Open Threat Signaling (DOTS). The goal is to
  provide some guidance for DOTS clients and client-domain DOTS
  gateways when multihomed.

Working Group Summary:

  The first version of the document was published as individual draft in June 2017.
  The draft was adopted as WG document in January 2019, but received very little
  WG attention until the fall of 2021, since the WG was busy with more urgent
  documents. The situation started changing after the WGLC for the document was issued
  and early reviews were requested, so that afterall the draft has been sufficiently discussed
  (with some definition of "sufficiently").

Document Quality:

  Document authors are also co-authors of core DOTS documents (signal channel, data channel etc.)
  To my best knowledge there is at least one implementation that follows guidelines from the document.

Personnel:

  Valery Smyslov (shepherd)
  Benjamin Kaduk (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 the document and found it ready.

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

  No. The document was a subject of reviews in the WG and by external experts (OPSDIR, SECDIR).

(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. 

  Early Reviews have been performed by Ops and Security Directorates.
  I personally don't think that more reviews are needed.

(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. 

  None.

(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?

  All authors and contributors confirmed that they are not aware of any IPR related to this draft.

  ** Mohamed Boucadair -- https://mailarchive.ietf.org/arch/msg/dots/snqL2m4aFISAk9ttDDqiGNCy2T8/
  ** Tirumaleswar Reddy -- https://mailarchive.ietf.org/arch/msg/dots/xx9dPak-0dX9SuR1QqlPbeJlZSQ/
  ** Pan Wei -- https://mailarchive.ietf.org/arch/msg/dots/uqndoqiklmiG_wMInsESm9H7UGc/

(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 that reference 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? 

  The WG consensus is solid.

(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. 

  No ID nits were found by idnits tool.

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

  None are applicable.

(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 8126). 

  The document contains no requests to 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. 

  No new registries are defined by this document.

(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.

  No automated checks are applicable.

(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?

  The document contains no YANG module.

(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? 

  Informational as indicated on the title page header and in the datatracker.

(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 discusses multi-homing considerations for Distributed-
  Denial-of-Service Open Threat Signaling (DOTS). The goal is to
  provide some guidance for DOTS clients and client-domain DOTS
  gateways when multihomed.

Working Group Summary:

  The first version of the document was published as individual draft in June 2017.
  The draft was adopted as WG document in January 2019, but received very little
  WG attention until the fall of 2021, since the WG was busy with more urgent
  documents. The situation was changes after the WGLC for the document was issued
  and early OPSDIR review was requested, so that the draft has been sufficiently discussed.

Document Quality:

  Document authors are also co-authors of core DOTS documents (signal channel, data channel etc.)
  To my best knowledge there is at least one implementation that follows guidelines from the document.

Personnel:

  Valery Smyslov (shepherd)
  Benjamin Kaduk (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 the document and found it ready.

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

  No. The document was a subject of reviews in the WG and by external experts (OPSDIR, SECDIR).

(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. 

  Early Reviews have been performed by Ops and Security Directorates.
  I personally don't think that more reviews are needed.

(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. 

  None.

(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?

  All authors and contributors confirmed that they are not aware of any IPR related to this draft.

  ** Mohamed Boucadair -- https://mailarchive.ietf.org/arch/msg/dots/snqL2m4aFISAk9ttDDqiGNCy2T8/
  ** Tirumaleswar Reddy -- https://mailarchive.ietf.org/arch/msg/dots/xx9dPak-0dX9SuR1QqlPbeJlZSQ/
  ** Pan Wei -- https://mailarchive.ietf.org/arch/msg/dots/uqndoqiklmiG_wMInsESm9H7UGc/

(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 that reference 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? 

  The WG consensus is solid.

(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. 

  No ID nits were found by idnits tool.

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

  None are applicable.

(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 8126). 

  The document contains no requests to 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. 

  No new registries are defined by this document.

(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.

  No automated checks are applicable.

(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?

  The document contains no YANG module.