Network Address Translation (NAT) Behavioral Requirements for the Datagram Congestion Control Protocol
draft-ietf-behave-dccp-05

Currently blocked in AUTH48 due to reference to draft-ietf-dccp-serv-codes that is blocked waiting for resolution on issues around license for code fragments. This should be resolved as soon as the new Trust Legal Provisions are published.

[Ballot comment]
The document completly lacks requirements or any manageability consideration for the NATs that support DCCP. I assume that a network operator should have means to understand what is the support provided by the NAT and what modes are implemented and can be configured on a given device. What is the minimal mode and status information that needs to be exposed to an operator by a NAT supporting DCCP and how is this information accessed and configured on a NAT device?

[Ballot comment]
Christian Vogt's review:

I was asked to review draft-ietf-behave-dccp-04 as input for IESG
evaluation, and I got three comments:

(1) On the abstract:

        Developing NATs that meet this set of requirements will greatly
        increase the likelihood that applications using DCCP will
        function properly.

    Sounds a bit like DCCP would work well only if we develop NATs. ;-)
    Better reword to:

        Ensuring that NATs meet this set of requirements will greatly
        increase the likelihood that applications using DCCP will
        function properly.

(2) On requirements 1 and 3:

        REQ-1: A NAT MUST have an "Endpoint-Independent Mapping"
        behavior for DCCP.

        REQ-3: If application transparency is most important, it is
        RECOMMENDED that a NAT have an "Endpoint-independent filtering"
        behavior for DCCP.  If a more stringent filtering behavior is
        most important, it is RECOMMENDED that a NAT have an
        "Address-dependent filtering" behavior.

    These requirements are general and not specific to DCCP.  Would it
    make sense to specify them in a separate RFC for NATs in general,
    independent of any specific transport protocol?

(3) On requirement 6:

        REQ-6: If a NAT includes ALGs, it MUST NOT affect DCCP.

    This requirement is not 100% clear.  I am assuming it means:  "If a
    NAT includes ALGs, the NAT MUST NOT affect DCCP packets that are
    processed by one of those ALGs."  Suggest to reword the requirement
    in this way.

[Ballot comment]
I recommend fixing this:

  "REQ-6: If a NAT includes ALGs, it MUST NOT affect DCCP."

Does "it" refer to the NAT or to the ALG?  I presume the latter but
that's not clear from the grammar.

[Ballot discuss]
The document completly lacks requirements or any manageability consideration for the NATs that support DCCP. I assume that a network operator should have means to understand what is the support provided by the NAT and what modes are implemented and can be configured on a given device. What is the minimal mode and status information that needs to be exposed to an operator by a NAT supporting DCCP and how is this information accessed and configured on a NAT device?

[Ballot comment]
Section 2., paragraph 2:
>    invidual DCCP flows, as uniquely identified by the quadruple (source
  Nit: s/invidual/individual/

Section 6., paragraph 1:
>    needed for an ALG to function.  Additionaly, there are no known DCCP-
  Nit: s/Additionaly,/Additionally,/

Section 7.2., paragraph 1:
>    REQ-8: A NAT MUST support "Hairpinning" for DCCP.  Futhermore, A
  Nit: s/Futhermore,/Furthermore,/

[Ballot discuss]
The text for REQ-5 covering timeouts for session abandonment in section 5 and the
corresponding security considerations seem in conflict.  Section 5 mandates minimum
timeouts of 124 minutes and 4 minutes for "established connection idle-timeout" and
'Transitory connection idle timeout" respectively.  These MUST requirements are followed
by a statement that the idle timeouts MAY be configurable.  I interpreted the section 5
text as permitting configuration with larger values only, since the minimums are given
as MUST statements.

The security considerations section implies that the configuration may result in values
smaller than the minimums specified in section 5.  This means the MAY overrides the
MUST statements?

To be clear, I am not asking for any particular resolution of this discrepancy, I am asking
for consistency only.

(1.a) Who is the Document Shepherd for this document?

Dan Wing, dwing@cisco.com

Has the
Document Shepherd personally reviewed this version of the
document and, in particular, does he or she believe this
version is ready for forwarding to the IESG for publication?

Yes.


(1.b) Has the document had adequate review both from key WG members
and from key non-WG members? Does the Document Shepherd have
any concerns about the depth or breadth of the reviews that
have been performed?

No concerns.


(1.c) Does the Document Shepherd have concerns that the document
needs more review from a particular or broader perspective,
e.g., security, operational complexity, someone familiar with
AAA, internationalization, or XML?

The WGLC was done in conunction with the DCCP working group.


(1.d) Does the Document Shepherd have any specific concerns or
issues 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. Has an IPR disclosure related to this document
been filed? If so, please include a reference to the
disclosure and summarize the WG discussion and conclusion on
this issue.

No concerns.



(1.e) 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?

There is solid WG consensus behind this document; many of its
recommendations are derived from BEHAVE's UDP document (RFC4787) and
TCP document (draft-ietf-behave-tcp).


(1.f) Has anyone threatened an appeal or otherwise indicated extreme
discontent? If so, please summarize the areas of conflict in
separate email messages to the Responsible Area Director. (It
should be in a separate email because this questionnaire is
entered into the ID Tracker.)

There has been no discontent.


(1.g) Has the Document Shepherd personally verified that the
document satisfies all ID nits? (See
http://www.ietf.org/ID-Checklist.html and
http://tools.ietf.org/tools/idnits/.) Boilerplate checks are
not enough; this check needs to be thorough.

Yes.

Has the document
met all formal review criteria it needs to, such as the MIB
Doctor, media type, and URI type reviews?

Yes.

If the document
does not already indicate its intended status at the top of
the first page, please indicate the intended status here.

intended status: Standards Track


(1.h) Has the document split its references into normative and
informative? 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
strategy for their completion? Are there normative references
that are downward references, as described in [RFC3967]? If
so, list these downward references to support the Area
Director in the Last Call procedure for them [RFC3967].

All references are verified by the document shepherd, and are good.


(1.i) Has the Document Shepherd verified that the document's IANA
Considerations section exists and is consistent with the body
of the document? If the document specifies protocol
extensions, are reservations requested in appropriate IANA
registries? Are the IANA registries clearly identified? If
the document creates a new registry, does it define the
proposed initial contents of the registry and an allocation
procedure for future registrations? Does it suggest a
reasonable name for the new registry? See [RFC2434]. If the
document describes an Expert Review process, has the Document
Shepherd conferred with the Responsible Area Director so that
the IESG can appoint the needed Expert during IESG Evaluation?

There are no IANA actions for this document.


(1.j) Has the Document Shepherd verified that sections of the
document that are written in a formal language, such as XML
code, BNF rules, MIB definitions, etc., validate correctly in
an automated checker?

The document contains no formal language.


(1.k) 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
Relevant content can frequently be found in the abstract
and/or introduction of the document. If not, this may be
an indication that there are deficiencies in the abstract
or introduction.


This document defines a set of requirements for DCCP-capable NATs
that would allow certain applications, such as streaming applications
to operate consistently.


Working Group Summary
Was there anything in the WG process that is worth noting?
For example, was there controversy about particular points
or were there decisions where the consensus was
particularly rough?

Nothing worth noting.


Document Quality
Are there existing implementations of the protocol? Have a
significant number of vendors indicated their plan to
implement the specification?

Unknown.


Are there any reviewers that
merit special mention as having done a thorough review,
e.g., one that resulted in important changes or a
conclusion that the document had no substantive issues?

They are listed in the acknowledgements section.

If
there was a MIB Doctor, Media Type, or other Expert Review,
what was its course (briefly)? In the case of a Media Type
Review, on what date was the request posted?

This document did not include such reviews, and doesn't need one.


Personnel
Who is the Document Shepherd for this document?

Dan Wing, dwing@cisco.com

Who is the
Responsible Area Director?

Magnus Westerlund, magnus.westerlund@ericsson.com

If the document requires IANA
experts(s), insert 'The IANA Expert(s) for the registries
in this document are .'

No experts are needed.