Write-up for draft-ietf-dhc-relay-server-security-02
(1) What type of RFC is being requested (BCP, Proposed Standard,
Internet Standard, Informational, Experimental, or Historic)? Why
is this the proper type of RFC? Is this type of RFC indicated in the
title page header?
Standards track. This I-D clarifies how DHCPv4 and DHCPv6 traffic between
servers and relays should be protected and uses normative language.
Therefore this is the right type. The intended type is clearly
indicated in the page header.
(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:
DHCPv4 has no guidance for how to secure messages exchanged between
servers and relay agents. The DHCPv6 states that IPsec should be
used to secure messages exchanged between servers and relay agents,
but does not require encryption. And, with recent concerns about
pervasive monitoring and other attacks, it is appropriate to
require securing relay to relay and relay to server communication
for DHCPv4 and DHCPv6. This draft codifies how to use IPsec with
encryption to secure that communication.
Working Group Summary
This draft was created as a result of a concern raised by during
IESG review of draft-ietf-dhc-access-network-identifier (https://
The issue was the DHCP options could reveal user identifying
information when a client communicates with a server via
relay(s). This was a generic DHCP issue, so the decision was made to
write a separate draft. Using IPsec for that purpose seems to be an
obvious choice and that is what the draft proposes.
This draft was first presented in Buenos Aires (April 2016) and
later in Berlin (July 2016) and got unanimous support in the room on
both occasions. It was adopted in Sep. 2016. The draft is very short
(a bit over 2 pages of actual content) and changed very little
between its first individual revision and the rev that passed
WGLC. That is understandable, as it codifies the obvious solution
implied by RFC3315 and was written by two experienced engineers (one
of them being DHC co-chair). This is also the reason why this draft
received fewer comments than average. In total, there were 37
messages related to this draft posted to DHC list and a handful more
circulated off the list.
This document is of high quality. The reviews it received my seem
like not too thorough, but that's because of the draft's shortness
and a high quality of its initial version. The authors are two
experienced DHCP engineers working for Cisco. I have personally
reviewed -01 rev of this draft had some minor comments. They were
addressed in -02.
Who is the Document Shepherd? Who is the Responsible Area
Tomek Mrugalski is the shepherd. Suresh Krishnan is the responsible 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
I reviewed the document before its adoption. I thoroughly reviewed
this document second time during WGLC (-01):
The minor issues I pointed out were addressed properly. This
document is ready for publication in my opinion.
(4) Does the document Shepherd have any concerns about the depth or
breadth of the reviews that have been performed?
No, at least not from the DHCP perspective. An extra review from
security experts would be welcome. Ops-dir feedback would be
probably be useful, too.
(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
This I-D is DHCP-centric, so DHC is the proper WG for this work. It
would be useful to have sec-dir review of it. This draft was
reviewed by Stephen Farrell on Oct. 14, 2016, but sadly his (brief)
comments were sent off the list, so the review is not well
documented. I was part of that discussion. I confirmed that
Stephen's comment was addressed in -01.
(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
I have no such concerns, except asking for a sec-dir review and
optionally ops-dir review.
(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, both authors confirmed in writing. There are no IPRs, existing or
(8) Has an IPR disclosure been filed that references this document?
If so, summarize any WG discussion and conclusion regarding the IPR
(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 consensus is pretty solid. There was an unanimous nod of
approval in the room when it was presented. Usage of IPsec with
encryption is the obvious choice and some deployments are already
doing it. Sadly, not a lot of people thought it is important enough
to confirm their approval on the ML. That's probably because RFC3315
indicated that already and that's what people typically do when they
need to secure their relay-server communication.
(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.)
(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
There are 3 idnit comments and all of them are not a problem. First,
the draft uses pre-RFC5378 disclaimer, because it contains text from
RFC3315 (which we know some of the authors are not reachable).
Second is the publication year not matching current. Yes, it was
published in 2016 and that is stated correctly.
The third nit is for outdated reference (sedhcpv6-18, with -20 being
available). This will be fixed by RFC Editor. Sedhcpv6 authors are
eager to update their draft as soon as any comments arrive (11
revisions in the last 13 months), so trying to keep up would be a
waste of time.
(12) Describe how the document meets any required formal review
criteria, such as the MIB Doctor, media type, and URI type reviews.
No such review is required.
(13) Have all references within this document been identified as
either normative or informative?
(14) Are there normative references to documents that are not ready for
advancement or are otherwise in an unclear state? If such normative
references exist, what is the plan for their completion?
No. All normative references are to published RFCs only.
(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. There are no such 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.
No. Even though this I-D introduces changes to RFC3315, the WG doesn't
want to enforce IPsec encryption on every DHCPv6 server. Therefore
it does not update RFC3315.
(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).
This document does not require any IANA actions. That is clearly
stated 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.
There are no such registries defined.
(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.
There are no such sections, so automated checks are not necessary.