Subject: [mobile-ip] Minutes of WG meeting at IETF51 (Draft version)

From: "Patil Basavaraj (NET/Dallas)" <[email-masked]>
Date: Tue, 28 Aug 2001 09:08:38 -0500

Hello,

Below are IETF51 WG meeting minutes. Please let me know if there
are any discrepancies. The minutes will be submitted to the IETF
secretary on Monday Sept 3rd (with any corrections if required).

Basavaraj 
Phil

Mobile IP WG meeting minutes for IETF51
---------------------------------------

/////////////////
//  Session 1  //
/////////////////

August 6th, 2001 (1930-2200)
Reported by : Jayshree Bharatia

Document Status :
- draft-ietf-mobileip-mier-07.txt (submitted)
- draft-ietf-mobileip-gnaie-04.txt (submitted)
- draft-ietf-mobileip-3g wireless-ext-06.txt (being updated based on
  IESG feedback)  
- draft-ietf-mobileip-rfc2002-bis-06.txt (being updated based on IESG
  feedback)  
- draft-ietf-mobileip-gen-key-00.txt (WG last call expired Friday 7/20
  hopefully submitted) 
- draft-ietf-mobileip-aaa-key-07.txt (to be submitted Friday 7/20)
- draft-ietf-mobileip-qos-requirements-00.txt (WG last call expired
7/25)
- draft-ietf-mobileip-reg-tunnel-04.txt (being updated)
- draft-ietf-mobileip-optim-10.txt (past WG last call, sitting on it
  until MIP v6 issues resolved) 

Moving MIPv4 to draft standard - Charles Perkins
================================================
Charlie Perkins provided current status and reasoning of why RFC2002
should move toward draft standards from its current status as proposed
standards. He mentioned that multiple interoperability tests have been
performed and there has been significant deployment exist today. The
following implemented options were pointed out: 
- 'R' bit in the agent advertisement => may be superseded by AAA work
- Prefix length extension in agent advertisement => never implemented
  and not interoperated 
- 'S' bit in registration request message => haven't shown
  interoperability, refers to simultaneous registration with separate
  COAs 
As per 2002Bis-o6 draft, Mobile IP implementations should include
HMAC-MD5 as one of the additional authentication algorithms. This
algorithm is used for producing and verifying the authentication data
in Mobile IP registration messages. If the requirement of using
HMAC-MD5 is mandated, it may take six more months before draft moves
for the last call. He insisted that the working group should influence
this decision. The alternative suggested was to remove this portion
from the 2002Bis draft and progress the draft for the proposed
standards. It was pointed out by Thomas Narten that it is not required
to have implementation of HMAC-MD5 in order to progress toward
proposed standards. In the end it was decided that the decision would
be taken based on the further WG mailing list discussion. 

Mobile IP v6 security update - Phil Roberts
===========================================

The discussion was based on MIPv6 protocol and the requirements for a
security solution discussed in draft
draft-team-mobileip-mipv6-sec-reqts-00.txt. It was mentioned by Raj
that the draft has an approval from security ADs and pointed out
a couple of outstanding items like implementation and usage of
IPSec. The current goal is to progress MIPv6 draft to PS by the end of
year
2001.  
The current proposals that specify alternative solutions for the
binding update problem are:
- draft-thomas-mobileip-ha-cookies-00.txt
- draft-perkins-bake-01.txt
- draft-montenegro-sucv-01.txt
The intent is to have an agreed upon solution that is acceptable to
the security area directors and meets the requirements specified in
the requirements I-D.

Further discussion lead to whether Routing Optimization should be a
part of this draft and its impact on 3GPP2 work. 

Mobile IP v6 other changes - Charles Perkins
============================================

Charlie brought up the issue related to authentication data passed with
a
binding update destination option. The working group comments received
on this topic were that it is currently unclear in the draft on how
IPSec can be used and how to handle potential IPSec problems. Also the
issue with piggybacking IPSec on binding update data is still
open. The further discussions on ESP vs AH may be continue on the
mailing list. It seems home agent discovery may need some more work
but other than this, the draft may be ready for the WG last call. 

Low Latency Handover - Karim El-Malki
=====================================

Short update of the draft-ietf-mobileip-lowlatency-handoffs-v4-01.txt
presented by Karim. It seems draft discusses mainly three handoff
techniques, pre-registration, post-registration and combined of the
above two. This draft is completed and may be ready for the last WG
call. The discussion lead toward using trigger defined from
mayfolks-l2-trigger draft rather than defining separate subset
specific to this work. Co-chair pointed out that by doing this, there
might be a problem of introducing dependency. No decision was made in
the meeting on this issue. 

Fast Handover - Gopal Dometty
=============================

Gopal presented updates on draft-ietf-mobileip-fast-mipv6-01.txt. As
per this draft, the mobile node can initiate a handover while it still
has L2 connectivity to the current access router and about to move to
a new access router. It seems there are some minor editorial changes
made to this draft. He claimed that L2 and L3 are decoupled. Pat
pointed out that access point is nothing but the foreign agent and
hence it will have L3 address. Gopal pointed out that L3 information
is generally obtained from L2. There is no agent advertisement
involved here and hence may reduce delay. Also old CoA is reused. 

BETH - James Kempf
===================

James provided brief overview of BETH. He mentioned that BETH defines
extension to the Fast Mobile IPv6 handover protocol described in
draft-ietf-mobileip-fastmipv6-01.txt that reduces the amount of L3
latency in Mobile IPv6 handover to zero. It also removes routing loop
problem. There were many questions raised by the group like how the
new AR detects when the MN has an operational new CoA and tunnel tear
down is started; bicasting is specified but the smoothing is not well
understood; this draft may be dealing with rare cases only; for
certain type of radio links the solution provided by this draft may
not work etc. 

The proposed plan is to incorporate BETH into the FMIPv6 specification
as another way for achieving fast handoff. The scheme currently
existing in the low-latency (v4) will also be aligned with the BETh
proposal. 

FMIPv6 Implementation experience report - Rajeev Koodli
=======================================================

Rajeev provided brief summery of FMIPv6 implementation
experience. Handovers are all network initiated using UNIX based
router, LINUX MN on 11 Mbps WLAN. The following issues were identified 

- What destination address to use in the F-BU? It was confirmed by
  group that global IP address should be used instead of local address
  as suggested by current specifications 
- Creating binding cache entry on previous access router (after
  receiving Hack and after sending F-Back to the old link). It was
  concluded that this is implementation specific and doesn't really have
  any protocol impact. 
- What source address to use when sending F-BU from newer AR?
- Issues may be related to sending of F-NA (including only one IP
  address suffices). The group provided comments that it is essential to
  know both Hack and F-Back. 
- When to change default router? There are two options proposed: after
  receiving proxy PA (may be not) or after actually attaching to the new
  link (the new AR). 

Handover Smoothing - Phil Roberts
=================================
 
Phil pointed out that smoothing is currently part of low latency draft
(draft-ietf-mobileip-lowlatency-handoffs-v4-01.txt) along with
simultaneous binding and currently it is not supported in FMIPv6. The
current proposal is to add handover smoothing to the FMIPv6 draft and
remove it from the low latency draft. The following comments/proposals
were received from the group 
- FMIPv6 and smoothing may be defined as optional
- Bicasting may be treated as implementation specific.
- Bicasting is a useful feature needed for handovers
- There may be lot more work involved in removing smoothing from the
  low latency draft 
- Bicasting is meant for achieving fast handovers and not necessarily
  for the handover smoothing 

Discussion on smoothing vs bicasting and buffering. It was determined
that smoothing has a larger scope than either bicasting and/or
buffering and should be considered as a separate work item. 
However for the fast handoff work a consensus call was done to
determine if bicasting should be included as part of the FMIPv6
specification. 
The final consensus was to move bicasting to a separate document for
both the v4 and v6 fast handoff drafts.

/////////////////
//  Session 2  //
/////////////////

August 7th, 2001 (1700-1800)
Reported by : Basavaraj Patil 

Consensus call for including bicasting in the fast handoff document
was not very clear at the previous meeting. Clarified the question
requiring consensus. The consensus call essentially was to see if
people wanted to see bicasting as another option within the fast
handoff specification. Consensus reached: Separate bicasting from fast
handoff. 

LMM Requirements - Carl Williams
================================
[draft-ietf-mobileip-lmm-requirements-00.txt]

Carl presented the major issues that have been raised on the Mobile IP
mailing list since the last IETF[50] w.r.t LMM. The draft with Carl as
the editor captures the requirements for an LMM solution. Discussion
focused around obtaining consensus on the requirements and also to
clarify the issues that have been previously discussed.
One major issue that continues to persist is the one dealing with the
levels of hierarchy. A long discussion on the pros and cons of single
vs multiple levels of hierarchy ensued.

Since there was no conclusion on levels of hierarchy, it was decided
that Carl would work with some of the interested people on this topic
to arrive at some consensus. This should be documented in the next
revision of the requirements document.

Mobile Network Suppport - Thierry Ernst
=======================================
[draft-ernst-mobileip-monetv6-00.txt]

Thierry Ernst presented the draft on support for mobile networks and
routers for IPv6 using Mobile IPv6. 
Obviously this topic needs to be investigated more as it raised more
questions than answers at this time. Basavaraj mentioned that the work
does
fit into the Mobile IP WG as the charter does not limit the scope to
just mobile hosts. There were some concerns about stepping into MANET
boundaries. 
Erik Nordmark mentioned that the issue of authorization for mobile
networks is a hard problem to solve and hence suggested that more work
needs to be done in this area. 
Opinions on the need for this work being done in the MIP WG were
expressed by many people. 
Conclusion was that more work needs to be done in this area. This
draft is a good starting point and could be used to investigate the
issues raised by Thierry in his presentation.

Nat Support in Mobile IPv4 - Henrik Levkowetz
=============================================

A small group of WG members who are interested in having MIPv4 work in
networks using NATs met the previous day. Conclusion reached at this
meeting was that Mobile iPv4 does not currently work very well in a
NAT world and scenarios where support for MIPv4 with NATs is required
were discussed.
Henrik presented the conclusions of the discussion and the need for
a solution for Mobile IPv4 over NATs.

Most WG members agreed that this work is important for MIPv4
deployment. A discussion list will be setup to discuss the scenarios
and requirements for NAT support in MIPv4. The WG will make a decision
regarding the inclusion of supporting NATs as a WG item at a later
time [i.e after the scenarios and requirements draft are done].

Mobile IP Component Redundancy - Gopal Dometty
==============================================
[draft-subbarao-mobileip-redundancy-00.txt] 

This could not be presented due to a lack of time.

Other MIP issues - Basavaraj Patil
==================================

Discussion item was skipped due to a lack of time.

The presentations used for the items above are available at:
http://people.nokia.net/~patil/MobileIP_IETF51

---

From: Alexandru Petrescu <[email-masked]>
Date: 28 Aug 2001 17:24:04 +0200

Basavaraj, thank you for the minutes, very useful.  Regarding
> Mobile IP v6 security update - Phil Roberts

the minutes mention three draft proposals:
 - draft-thomas-mobileip-ha-cookies-00.txt
 - draft-perkins-bake-01.txt
 - draft-montenegro-sucv-01.txt

IMHO, other drafts treat of same subject:

draft-le-mobileip-dh-00.txt
draft-mkhalil-mobileip-ipv6-sap-02.txt
draft-roe-mobileip-updateauth-00.txt

Alex