[MEXT] Issue #18 ["Home Address Option & ICMP / Binding errors"], part 3 of 3: "Receiving Binding Errors"

["Charles E. Perkins" <charles.perkins at earthlink.net>]

Hello folks,

Last month, issue #18 showed up without any fanfare on the
issues tracker list:
   http://trac.tools.ietf.org/wg/mext/trac/ticket/18
I'd like to initiate discussion on the points raised as part
of issue #18.  There are three main points, which can be
discussed separately.  In this note, I transcribe the
discussion about the third of the three points.

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

Receiving Binding Errors

In Section 11.3.6. Receiving Binding Error Messages, it is not
considered that Binding Error Messages can also come from Home
Agents when acting as a Correspondent Node to its Mobile Nodes
[see also issue #12]. It is only defined that:
   "If the mobile node has no upper layer progress information,
   it MUST remove the (Binding Update List) entry (from the
   Correspondent Node) and route further communications through
   the home agent. It MAY also optionally start a return
   routability procedure (see Section 5.2)."

If the Correspondent Node is the Home Agent, it is likely that
there is also no tunnel to route communications through. This
case may happen if the Home Agent reboots without a persistent
storage of its Binding Cache.

Proposal: If the Binding Error Message was sent by the Home Agent,
the Mobile Node SHOULD send a Binding Update to the Home Agent
according to Section 11.7.1.


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

Please submit comments on the above discussion and proposal.
If consensus is reached soon, I will incorporate the consensus
text in a revision of rfc3775bis to be released before the next
IETF.

Regards,
Charlie P.