Subject: [mobile-ip] Conclusion and Recommendation for unverified HAO Processing

From: [email-masked]
Date: Fri, 8 Mar 2002 10:06:14 -0600

Hello,

The unverified home address option processing proposal has been
discussed on the mailing list over the last few days. 
The conclusion is that while the proposed tagging mechanism provides
traceability, filtering when tagging is used is not yet clearly
understood.
Hence the recommendation in order to make progress is as follows:

The base Mobile IPv6 specification will take the following approach:
- CNs must not process packets with Unverified HAO 
- A CN must send an error response to a MN sending packets with
  unverified HAO , indicating its inability to process such packets by
  sending an error message specified in the base draft.
   * This error mechanism should be extensible so that different types
     of error notification can be added e.g. when unvHAO support is
     specified.  

- With future extensions and specification, MNs may optimistically
  send packets with unverified HAO to a CN, but on receiving an error
  response, MNs  must resort to bidirectional tunnelling to send
  packets to the CN. 

With this approach triangle routing is not completely eliminated from
Mobile IPv6. It leaves the door open for a future specification that
can specify the rules for a CN to process packets with unverified HAO.
When such a specification is available and standardised by the Mobile
IP WG:

- CNs must/should process packets with unverified HAO (under the rules
  defined) 
- MNs  that send packets with unverified HAO to a CN will not receive
  an error response from such CNs 

-Basavaraj