Subject: Re: [mobile-ip] Mobile IPv6 draft revision

From: "Peter Grimstrup (TED)" <[email-masked]>
Date: Thu, 23 Aug 2001 12:40:45 +0200

From draft-14:

8.5. Sending Binding Acknowledgements

                   and the packet MUST be sent using a Routing header
                                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   in the same way as any other packet sent to a mobile node using a
   care-of address (even if the binding was rejected), as described in
   Section 8.9.

8.9. Sending Packets to a Mobile Node

   Before sending any packet, the sending node SHOULD examine its
   Binding Cache for an entry for the destination address to which the
   packet is being sent.  If the sending node has a Binding Cache entry
   for this address, the sending node SHOULD use a Routing header

I find the 2 sections in conflict. Further sec. 5.2 also says
"The packet is sent using a routing header"

Comments to De-registration (not touching the questions raised by
Francis Dupont recently).

The deregistration may be sent from
 a) the Home Address (any Lifetime)
 b) the latest Care Of Address (Lifetime = 0)
 c) another address (Lifetime = 0)

First the Binding Cache Entry (BCE) is deleted (see sec. 8.4 and 9.2)
then the Binding Acknowledgement (BA) is sent.

As mentioned above, the BA must be sent with a routing header, but
we have no BCE anymore.

In case a) the BA should be sent to the Home Address (in this case a
routing header is not really needed, doesn't harm much either).
In case b) and c) the BA could reasonably be sent back to the source
address of the deregistration, which in case b) is the BCE just deleted.

This procedure is very much the same as described in sec. 5.2 when
*rejecting* a BU - in this case, however, the BU is not rejected and
the acceptance procedure is used.

Have I missed something or should this be added/clarified in the draft?

Peter

---

From: Brian Haley USG <[email-masked]>
Date: Tue, 28 Aug 2001 14:51:09 -0400

"Charlie Perkins" wrote:

> Following the recent discussion, I believe a new revision to the
> existing Mobile IPv6 draft ...-14 is needed.
> 
> Comments?

Hi Charlie,

Here are some comments I have on draft -14.

Section 6.4 (HA info option)

 The last paragraph starts:

  "If both the Home Agent Preference and Home Agent Lifetime are set
   to their default values specified above..."

 but a default value for Home Agent Lifetime is never discussed.
 Maybe it should be the same as the Router Lifetime value that
 would be sent in an RA?

Section 6.5 (Router advert changes)

 Why has the MinRtrADvInterval shrunk to 0.05 seconds from 0.5 seconds?

Section 8.2 (Recieving BUs)

 This still has the old wording in bullet #4 that:

  "The Sequence Number field in the Binding Update option is greater
   than the Sequence Number received in the previous Binding Update
   for this home address, if any. ..."

  "Any Binding Update not satisfying all of these tests MUST be
   silently ignored..."

 Section 5.2 has the correct wording that should be put here:

  "If the mobile node sends a sequence number which is not greater than
   the sequence number from the last successful Binding Update, then the
   home agent MUST send back a Binding Acknowledgement with status code
   141, and the last accepted sequence number in the Sequence Number
   field of the Binding Acknowledgement."

Section 8.5 (Sending BAs)

 The second paragraph mentions IPsec:

  "The packet in which the Binding Acknowledgement is returned MUST meet
   the specific IPsec requirements for Binding Acknowledgements..."
 
 it should maybe say "security".

Thanks,

-Brian