Mobile IPv6 (MIPv6) Bootstrapping for the Integrated Scenario
draft-ietf-mip6-bootstrapping-integrated-dhc-06

[Ballot comment]
The introduction says:

"In the integrated scenario, the bootstrapping of the home agent  information can be achieved via DHCPv6."

There is no motivation or reasoning why this is a good thing and whether DHCP is really the right mechanism for this problem. Also, it is not clear from the current text whether this is the only proposed mechanism as DHCP is certainly not used everywhere, especially in the mobile scenario and in the case of ipv6 connectivity bootstrapping.

[Ballot comment]
The introduction says:

"In the integrated scenario, the bootstrapping of the home agent  information can be achieved via DHCPv6."

There is no motivation or reasoning why this is a good thing and whether DHCP is really the right mechanism for this problem. Also, it is not clear to me whether this is the only proposed mechanism as DHCP is certainly not used everywhere, especially in the mobile scenario and in the case of ipv6 connectivity bootstrapping.

[Ballot discuss]
The DISCUSS is largely based on comments from OPS-DIR reviewer David Kessens:

1. The introduction says:

"In the integrated scenario, the bootstrapping of the home agent  information can be achieved via DHCPv6."

There is no motivation or reasoning why this is a good thing and whether DHCP is really the right mechanism for this problem. Also, it is not clear to me whether this is the only proposed mechanism as DHCP is certainly not used everywhere, especially in the mobile scenario and in the case of ipv6 connectivity bootstrapping.


2. In section "3.  Assumptions & Conformance":

"c. DHCP relay and NAS are collocated or there is a mechanism to
    transfer received AAA information from the NAS to the DHCP relay."

Does this really work? A DHCP relay is just a relay. Eg. the relay cannot really do anything it's function is to relay information to the DHCP server and it's behavior is standardized by dhc so 'some mechanism' means a change to the DHC relay protocol while doing this straight to the DHCP server can be done in a proprietary manner which can work, but is probably not desirable (note: I am not a DHCP expert so let me know if I am wrong!). In general, I am not sure whether it is intended that DHC relays are supposed to expose such active behavior as opposed to just relaying messages.

[Ballot comment]
1. The abstract contains a very obvious typo/grammar error (search for 'the the'). Not a big deal by itself but I always ask myself how well this document has been reviewed if there are already obvious issues in the abstract. Otherwise, the document seem to be well written and the pictures are easy to understand.

2. I will leave this to the security review but it seems that the security section is inadequate in the sense that it doesn't mention the security considerations that are inherent for DHC are obviously inherent for this solution as well as it uses DHCP.

[Ballot discuss]
The DISCUSS is largely based on comments from OPS-DIR reviewer David Kessens:

1. The introduction says:

"In the integrated scenario, the bootstrapping of the home agent  information can be achieved via DHCPv6."

There is no motivation or reasoning why this is a good thing and whether DHCP is really the right mechanism for this problem. Also, it is not clear to me whether this is the only proposed mechanism as DHCP is certainly not used everywhere, especially in the mobile scenario and in the case of ipv6 connectivity bootstrapping.

2. "The specification utilizes DHCP and AAA  options and AVPs that are defined in [HIOPT], [MIP6-Dime], and  [MIP6-RADIUS]."

I wonder how this document can be on the agenda if none of the above documents are approved yet and/or reviewed to the point where we are confident that these specifications are really stable.

3. It is not clear whether this document ever got reviewed by the dhc, radius and dime working group.

4. In section "3.  Assumptions & Conformance":

"c. DHCP relay and NAS are collocated or there is a mechanism to
    transfer received AAA information from the NAS to the DHCP relay."

Does this really work? A DHCP relay is just a relay. Eg. the relay cannot really do anything it's function is to relay information to the DHCP server and it's behavior is standardized by dhc so 'some mechanism' means a change to the DHC relay protocol while doing this straight to the DHCP server can be done in a proprietary manner which can work, but is probably not desirable (note: I am not a DHCP expert so let me know if I am wrong!). In general, I am not sure whether it is intended that DHC relays are supposed to expose such active behavior as opposed to just relaying messages.

[Ballot comment]
Section 4.3 is "DHCP Server Behavior" but the first sentence talks about tyhe mobile node
recieving a relay-forward message.  As I skimmed 3315, it appears the relay-forward
message is transmitted from the relay agent to the dhcp server.

[Ballot discuss]
The security considerations section notes that there is no impact
on DHCP security, but fails to describe the implications for mobile
IPv6.  RFC 3315 notes a number of issues that *could* be important:

The DHCP threat model does not consider the privacy of the contents of
DHCP messages to be important.  I would think that home network
information could be considered sensitive in cases, couldn't it?

However, communication between a server and a relay agent, and
communication between relay agents, can be secured through the use
of IPSec, as described in section 21.1.  Does the transmission of
home network information make IPSec more important to apply?

DHCP authentication provides for authentication of the identity of
DHCP clients and servers, and for the integrity of messages delivered
between DHCP clients and servers.  Is this service likely to be
available in the mobile case?

I would like to see a summary of the implications of this spec for
IPv6.  (Stating that there are none is okay if that is really the
case, although I am initially skeptical!)

[Ballot comment]
The security considerations say:
  >
  > No additional security considerations are imposed by the
  > usage of this document.
  >
  The security considerations ought to address any concerns that need
  to be handled by things that are not "imposed" by this document or its
  normative references.  Are there any here?

  The figures seem to have double captions.

DHC WG chair Ralph Droms: Looks like WG was OK to send integrated-dhc to IESG together with a fixed hiopt draft.  I think it's OK to go to IETF last call.

[Note]: 'Document Shepherd is Basavaraj Patil <basavaraj.patil@nokia.com>
Document waiting on mip6-hiopt resolutions before it can complete succesful WGLC in DHC WG' added by Jari Arkko

[Note]: 'Document Shepherd is Basavaraj Patil <basavaraj.patil@nokia.com>
Document waiting on mip6-hiopt before it can complete succesful WGLC in DHC WG' added by Jari Arkko

I have made my AD review on this document. It is generally
in good shape, but I would like to raise the following two
issues:

1. The document assumes that there is communication between
    the NAS and the DHCP server/relay parts in the visited
    network. From what I can see, such communication is
    only needed, however, if the assigned home agent information
    is going to differ between mobile nodes in a certain
    way. Specifically, if the assignment decision depends on
    local criteria (load in different home agents, round-robin
    status) and policy that does not differ between AAAHs
    or mobile nodes, then no such communication is needed.

    Not having to assume co-location or communication
    would simplify the implementation of this considerably.
    This would also cover one important use case that I
    can see, an access network that offers local home
    agents without any specific additional agreements
    or roaming services.

    Has such a case been considered in the discussion?
    Is it feasible to allow devices to implement
    such a simplified mode of operation?

2. A review in DHC WG needs to happen to ensure that
    the planned model is in line with what the DHCP experts
    feel is achievable. I will ask the chairs to arrange this
    before we go to IETF Last Call.

PROTO Write-up

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

Document shepherd: Basavaraj Patil
Yes, I have reviewed this version of the I-D and believe it is ready
for forwarding to IESG.


(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?

The document has been reviewed within the MIP6 WG. It was developed by
a design team and then subsequently discussed as an open WG document
on the mailing list. It has been reviewed by WG members as well as
non-WG members.

(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?

I believe the document has had sufficient review and by people who
understand various aspects other than Mobile IPv6. There is no need to
have further review from other areas.

(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.

I do not have any concerns or issues with the document. All issues
have been addressed in revisions of the document.


(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 WG consensus on this bootstrapping mechanism. Strong
consensus comes from a few active WG members as is the case for most
documents. The WG I believe understands this document and the need for
the solution specified in this I-D. There are no major objections at
least to the I-D.


(1.f) 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
entered into the ID Tracker.)

No.


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

Yes. I have verified the I-D for ID-nits via the tool provided in
tools.ietf.org. The I-D does not specify a MIB or media type. Hence no
formal review of such aspects in the I-D are required.


(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].

Yes.

(1.i) Has the Document Shepherd verified that the document IANA
consideration 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 Shepherd
conferred with the Responsible Area Director so that the IESG
can appoint the needed Expert during the IESG Evaluation?

No IANA action is required from 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?

Not applicable.


(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.

Mobile IPv6 bootstrapping can be categorized into two primary
scenarios, the split scenario and the integrated scenario. In the
split scenario, the mobile node's mobility service is authorized by a
different service authorizer than the network access authorizer. In
the the integrated scenario, the mobile node's mobility service is
authorized by the same service authorizer as the network access
service authorizer. This document defines a method for home agent
information discovery for the integrated scenario

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

The design team had some differences regarding the integrated
scenario and use of DHCP as a means for bootstrapping. However
these issues have subsequently been clarified. The current I-D in a
previous version included several DHCP options which are required
for bootstrapping. These have now been specified in a separate
I-D (draft-ietf-mip6-hiopt-03.txt). This I-D is dependent on the
DHCP options specified in the companion MIP6 WG Doc:
draft-ietf-mip6-hiopt-03.txt


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

No known implementations of this protocol exist at the current
time. However some vendors have indicated plans to implement this
specification. This specification is also of interest in other SDOs
such as 3GPP2 and WiMAX forum.

Acknowledgements to the key reviewers and contributors have been
noted.


-Raj