[Netext] Charter Scope and Work Items

[sgundave at cisco.com (Sri Gundavelli)]

IMHO, there are number of extensions to Proxy Mobile IPv6 that we need for 
successful deployment of the protocol in any system architecture. To most
part these are minor extensions that we need them for addressing a
deployment
problem, alignment with other protocols such as GTP, add a minor missing
feature useful in optimizations, or some thing that helps in
implementations.

I've identified some work items, that we discussed in the past. This is just
my opinion. Welcome to dispute. Also, Where ever we do this work, netext,
netlmm,
mext or mipshop, is not my interest, but we need these extensions. Thats the
only part I care. If this was discussed in the past, fine, but this is my 
list as I see it, bear with me.

All the items listed here do not require host stack changes, except the
following immediate list which may in some cases:

- Multi-homing Support, when sharing the same address on two interfaces
- Handoff triggers from the mobile node
- Flow Management, when not moved as a group associated to a prefix
- Prefix coloring via RA extensions

I really hope the charter will consider most of the work items listed
below.



1. Dynamic LMA Assignment

In blade architecture systems or in a load balancer configuration, the PDNGW
should have the ability to dynamically assign a LMA on the fly, along the 
lines of Mobile IPv4 Dynamic Home Agent Address Assignment support
[RFC-4433].
Currently, GTP provides such semantics and this is a important requirement
for deployment. Here the goal is to 

a.) Expose a single IP address to the SGW
b.) The exposed IP address should not be in path once the assignment is
done.



[LMA1]---
  |      |
[LMA2]--[LMA]==========[MAG]
  |      |
[LMA3]---


Along the lines of:

http://tools.ietf.org/html/draft-korhonen-netext-redirect-01



2. Multicast Support in Proxy Mobile IPv6

We need an informational specification on how multicast support can be
enabled in Proxy Mobile IPv6 environment. Behcet has done extensive analysis
on
this. This is required and critical for enabling any multicast services.
However,
Behcet may disagree with the scope of the work. 




3. Bulk Registration Support

This is a simple extension which helps in signaling optimization, along the
lines of:

http://tools.ietf.org/html/draft-premec-netlmm-bulk-re-registration-02




4. Partial Failover Support

We need a mechanism to notify the peer on revoke a partial set of bindings.

http://tools.ietf.org/id/draft-koodli-netlmm-path-and-session-management-00.
txt





5. Group Identifier Support for Proxy Mobile IPv6

This provides a simple and a generic semantic for assigning a group
identifier
to a mobile node's binding. GTP has very similar semantics, Connexion Set
Id.
Both #3 and #4 can leverage this. Additionally, in load balancer systems
where
the load balancer is in path for all signaling messages, it can use this as
a
tag for redirecting the message.

http://tools.ietf.org/html/draft-gundavelli-netext-mn-groupid-option-00



6. Virtual-Interface Support on IP host for supporting Inter-tech handoffs:


RFC-5213 supports handoff between two interfaces. The ability to move
prefixes between interfaces. In other words address continuity is assured
with any IPv6 host on the planet and with absolutely no changes. This meets
even Dave's comment, that "no changes to any IETF RFC's.". Now, what is
not assured is the aspect of session continuity. Which requires a virtual
interface implementation on the host, by binding the address/prefix to a
virtual interface and by not exposing the physical interface or by hiding
the handoff events from the layer-3 stack.

In essence, we need an informational specification which provides some
general guidance to how to leverage the feature support provided in
RFC-5213,
along the lines of:

http://tools.ietf.org/html/draft-yokota-netlmm-pmipv6-mn-itho-support-00



7. Route Optimization for Proxy Mobile IPv6

There were atleast 4 drafts in this area on Route Optimization. Marco
Liebsch
analyzed this exensively:


http://tools.ietf.org/html/draft-liebsch-netext-pmip6-ro-ps-00
http://www.ietf.org/internet-drafts/draft-koodli-netext-local-forwarding-00.
txt





8. Prefix Management in Proxy Mobile IPv6 support
 
Proxy Mobile IPv6 allows the assignment of multiple home network prefixes
to a given mobile node's interface. It might be useful to specify how the 
LMA manages this aspects. It can potentially use DHCP PD, Local Pools or
AAA to manage this aspect. Behcet has one draft on this.



9. Partial Handoff Support

We are missing some semantics in 5213 for moving a subset of the prefixes
between interfaces as part of the inter-tech handoff. This is about defining
a new handoff value. This allows partial flow management, but moving the
flows associated to a prefix, as a whole group.

http://tools.ietf.org/html/draft-jeyatharan-netext-pmip-partial-handoff-00




10. CMIPv4/PMIP Interworking

This is probably required to specify how an IPv4-only can move between 
CMIP and PMIP environments.

http://sunsite.mff.cuni.cz/MIRRORS/ftp.rfc-editor.org/internet-drafts/draft-
meghana-netlmm-pmipv6-mipv4-00.txt




11. NEMO/Prefix delegation to Mobile Node in Proxy Mobile IPv6