Subject: [mobile-ip] Multiple flows with single NAI

From: Madhavi Subbarao <[email-masked]>
Date: Mon, 30 Apr 2001 19:53:01 -0400

Hi All,

For viable deployment of MIP, it seems necessary to support single NAI
with multiple static IP flows.  For example, if a user opens a MIP
session on his laptop and then wants another MIP session on his phone,
he couldn't do that now with a single NAI .  Now when an HA receives
an RRQ with NAI and homeIP#2, but it already has a binding for NAI
and homeIP#1, the binding gets 'overwritten'.  Hence, only one MIP
flow can be supported per NAI.  Theoretically, we can say to use
multiple NAIs, but practically, it's not possible.  Many service providers
do not want to create multiple NAIs and user records for multiple
devices/applications or instances of the mobile user.

While it seems natural then to allow multiple static IPs for the same NAI 
(dynamic IPs also, but that needs another level of identification),
neither RFC2002 nor RFC2974 outline the behavior that should be
followed by the various entities.  The specs certainly do not preclude
the above, but clarity in behavior is needed.

We believe this is a simple, yet important issue for deployment and would
like feedback from the WG.

We've submitted a draft that addresses the above.
http://search.ietf.org/internet-drafts/draft-subbarao-mobileip-multipleip-00.txt

Thanks,
Madhavi