Subject: [mobile-ip] Fast Handover document revision

From: Rajeev Koodli <[email-masked]>
Date: Mon, 10 Feb 2003 18:24:47 -0800

Hello folks,

I wish to revise the document. Specifically, I would
like to address the following.

1. Securing the Fast Binding Update. I would like folks to provide
    input on this. What should we do ?

2. Regardless of whether FBack is received or not, the MN always sends
    the same message to the new router. This message
    - confirms new CoA
    - announces the MN's presence to the new router

    The message itself would be a refined FNA, as an option in the
Router
    Solicitation message. The response would be a NAAck option in the RA

    message.

    What do folks think about this ?

3. Based on the discussion prior to the last IETF and
     during the last IETF, I would like to allow PrRtSol and PrRtAdv
    exchange to be possible ahead of the handover. So, for instance,
    a MN may exchange these messages upon attaching to a router.
    This means fewer messages during handover, shorter time for
    which the handover state needs to be managed and better chances
    of anticipating a new CoA. Also, the binding at the old router is
created
     upon processing the FBU, and is more consistent with the base
     Mobile IPv6 spec.
    Please acquaint yourself with the discussion on the ML and the
    presentation slides before you comment :-)

Regards,

-Rajeev

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From: "James Kempf" <[email-masked]>
Date: Tue, 11 Feb 2003 15:01:57 -0800

>     input on this. What should we do ?

Sorry to sound like a broken record, but if the signaling is confined to being
just between the current AR and MN, security for IPv6 Neighbor Discovery as
outlined in RFC 2461 and RFC 2462 can be used.

Unless I'm missing something, if the signaling is sent back to the PAR, as the
current FBU proposal does, I don't see how the signaling can be secured without
introducing another mechanism. The two ways of securing BUs currently accepted
are a) Return Routability to CNs or b) a specialized IPsec security association
with the HA. Leaving aside the question of how the MN gets a global address for
PAR in the first place, neither of these are appropriate in this case IMHO.

>     What do folks think about this ?

I think this the RS/RA should be reused for this purpose, as it cuts down on the
signaling and accelerates the MN's configuration on the new link.

>     presentation slides before you comment :-)

There are issues with anticipated address configuration, as discussed in a
separate email.

            jak

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From: Alper Yegin <[email-masked]>
Date: Thu, 13 Feb 2003 14:33:15 -0800

Hi Rajeev,

Thanks for following up on these issues.

>   input on this. What should we do ?

A mechanism to create a trust relation between the MN and its
current AR is needed. This can be used to send FBU once MN
leaves the link. PANA might be a possible candidate for that.

>   presentation slides before you comment :-)

I think this is a good idea in general, and our eFWD proposal
already has that. Address allocation expect of PrRtSol/PrRtAdv
might create issues though.. This requires some consideration.

alper

---

From: Alper Yegin <[email-masked]>
Date: Thu, 13 Feb 2003 14:48:06 -0800

> outlined in RFC 2461 and RFC 2462 can be used.

If we know how to create a trust relation between a MN and its current AR,
this should be useful even after MN moves off-link, hence you get a trust
relation between MN and its previous AR.

And tying this trust relation to some other identifier than the link-local
address should make it portable.

alper

---

From: Rajeev Koodli <[email-masked]>
Date: Thu, 13 Feb 2003 16:18:51 -0800

Hello Alper,

> might create issues though.. This requires some consideration.

As I have described in a previous e-mail, PrRtSol/PrRtAdv
do not trigger HI and HAck. So, the MN learns of new CoA to
use, but is only confirmed when FBack is received or via
refined FNA on the new AR.

Thanks,

-Rajeev