Subject: [MOBILE-IP] Appendix

From: "Charles E. Perkins" <[email-masked]>
Date: Thu, 9 Nov 2000 13:37:46 -0800

Hello folks,

Here is a stab at an appendix.  It needs proofreading, but
I have to go for now and I thought it would be better to
send something defective for now and touch it up more later.

My opinion is that a Binding Update is needed, and if it takes
another few hundred milliseconds, that's O.K.  So, I retained
that step for the part after the Router Advertisement was
received by the mobile node.  However, this is of course up
for discussion.

I reckon the hard part will be to manage the identification
for the mobile node.  As Hesham mentions, NAI could be used
for this.  However, I am sure that everyone agrees that right
now is not the time for trying to complete that discussion.

Regards,
Charlie P.

=====================================================================

A. Remote Home Address Configuration

   The method for initializing a mobile node's home addresses on
   power-up or after an extended period of being disconnected from
   the network is beyond the scope of this specification.  Whatever
   procedure is used should result in the mobile node having the same
   stateless or stateful (e.g., DHCPv6) home address autoconfiguration
   information it would have if it were attached to the home network.
   Due to the possibility that the home network could be renumbered
   while the mobile node is disconnected, a robust mobile node would not
   rely solely on storing these addresses locally.

   A mobile node MAY generate a temporary home address using the
   following information:

    -  the subnet prefix from the home network's mobile agent anycast
       address, and

    -  the globally unique interface identifier that would have been
       used to generate the link local address if the mobile node were
       attached directly to the home network.

   Such a temporary address could be used to establish a binding with
   a home agent in the absence of any other known home addresses.  It
   could be created with short valid lifetime and a preferred lifetime
   of zero to ensure a quick transition to other addresses generated
   when stateless or stateful (DHCPv6) address autoconfiguration runs.

   Such a mobile node could initialize by using the following procedure:

    1. Query DNS for the home network's mobile agent anycast address.

    2. Generate a care-of address using stateless or stateful
       autoconfiguration.

    3. Send a Home Agent Address Discovery Request message to the home
       network.

    4. Receive Home Agent Address Discovery Reply message.

    5. MN picks one Home Agent and tunnels an Router Solicitation to it.

          Outer src = care-of address
          Outer dst = Home Agent's global address
          Inner src = 0:0:0:0:0:0:0:0 (unspecified address)
          Inner dst = Home Agent's global address

    6. Home Agent returns a Router Advertisement, covered by AH. An SA
       has to be set up between MN's CoA and the HA. How this is done
       is out of scope, but MN and HA have some shared secret or can be
       verified by some agent.

       The Router Advertisement is returned by tunneling, as follows:

          Outer src = HA's global address
          Outer dst = care-of address
          Outer src = HA's home subnet link-local address
          Inner dst = all-nodes multicast address

    7. Mobile node parses Router Advertisement and configures all
       prefixes and addresses according to the method stated there.  If
       the the M or O flags are set in the router advertisement, follow
       the stateful (DHCPv6) configuration procedures.

    8. Send binding update option(s) to establish bindings for the new
       home addresses.

---

From: Mattias Pettersson <[email-masked]>
Date: Fri, 10 Nov 2000 10:49:23 +0100

Hi,

> now is not the time for trying to complete that discussion.

I think such a protocol is all above Mobile IPv6 and can without problem
be left out of this draft.

>     2. Generate a care-of address using stateless or stateful

In order to query the DNS the MN should probably need a care-of address,
so please swap 1 and 2.

>        the stateful (DHCPv6) configuration procedures.

Currently, as I said earlier, DHCPv6 won't really support such off-link
and off-site configuration, at least to my knowledge. This is out of
scope (an easy escape... someone has to fix this later, though).

>     8. Send binding update option(s) to establish bindings for the new

/Mattias

---

From: Francis Dupont <[email-masked]>
Date: Mon, 13 Nov 2000 09:09:05 +0100

In your previous mail you wrote:

=> this is out of scope but this is not easy... If you'd like to have
interoperability then you have to give more details about the AH
(is it an transport mode AH protecting the whole Router Advertisement
but not the encapsulation, ie. something produced by a "home link
security" as proposed by McDonald at a past IETF meeting?)

Thanks

[email-masked]