Subject: RE: [mobile-ip] Binding Error Message and HAO

From: [email-masked]
Date: Fri, 7 Jun 2002 14:25:14 -0500

>I'm trying figure out if we have already closed this issue.
>(http://www.piuha.net./~jarkko/publications/mipv6/issues/issue33.txt)
>
>The original question was what to fill in when there is no HAO.
>In another discussion on the list we have noted that the HAO
>can be included in BUs to the CN. We then discussed whether we
>could simply drop packets that don't have a HAO, and not even
>respond with a BE. Arvind noted that if the MH type is unrecognized,
>it is hard to know if a HAO should have been present or not. He
>proposed that the home address be placed in an option that could
>be carried by the BE when necessary.
>
>Note that the HoT message goes via the home agent and
>does not have a home address option. The source of the
>packet is the home address. So, what happens if the CN does
>not support this message, or some similar future message? 

If the CN does not support this message and RR is mandated as the
baseline RO mechanism for MIPv6, then obviously the CN does not have
the functionality required for supporting RO. I believe emphasizing
the need for CNs to implement RO functionality should be strongly
recommended (in lieu of making it a MUST).

>If we are strict about the no-BE-if-no-HAO rule then we can't
>send an error.

Capability to send an error message is required.

>My suggestions is therefore that a new mobility option should
>be created, the "Home Address mobility option" (can this be
>mistaken for the HAO -- any ideas for a better name?). This
>new mobility option would be included when the BE is sent
>with Status 1.
>
>Another alternative is to allow the home address field to be
>zero in the BE message, if HAO was not present in the offending
>message.

I like Option 2 (home address zero). 

>Jari

-Basavaraj

---

From: Jari Arkko <[email-masked]>
Date: Fri, 07 Jun 2002 23:52:03 +0300

> recommended (in lieu of making it a MUST).

HoTI was a good example for showing a message that doesn't use HAO.
Perhaps it wasn't as good example for showing how the CN must be
able to refuse such a message. Still, there might be some future
message for some mobility related purpose that also doesn't use HAO.

> I like Option 2 (home address zero). 

It would be simpler, yes. I don't feel strongly either way.
Anyone else?

Jari