Subject: Re: [MOBILE-IP] Fast Handoff v4 archives available

From: Roberts Philip-qa3445 <[email-masked]>
Date: Tue, 3 Oct 2000 08:42:29 -0500

Hi Luca,

> ----------
> From:         Luca Salgarelli
> Reply To:     Luca Salgarelli
> Sent:         Tuesday, October 3, 2000 4:46 AM
> To:   [email-masked]
> Subject:      Re: [MOBILE-IP] Fast Handoff v4 archives available
>
> Basavaraj, Andrew,
>
> I would like to add some comments to what Andrew wrote.
>
> > Regards the process: I thought the idea was to come up with a set of
> > requirements, then a strawman proposal that sort consensus and met the
> > requirements?
> >
> > It looks like the starting point was too narrow?
> >
> > It looks like the output from the design team resulted in deltas to
> > existing IDs? (Why are these two IDs technically superior to others?).
> >
> > In addition, weeding out some IDs because they didn't support tunneling
> > (e.g., Hawaii) or MIP messaging (e.g., CIP), etc.  was a bad call in a
> > process that should have been open and inclusive and now looks like on
> > the surface to have preselected two IDs (i.e., fast handoff/ proactive
> > IDs) that have not been proven "better" than others.
>
> I completely agree with Andrew. Several weeks ago I wrote a message to the
> WG asking clarifications about this process, but those questions were left
> unanswered. I too thought that the goal of this sub-WG (?) was to come up
> with a set of requirements. While I do not question the technical
> soundness
> of the proposals (not requirements) that this sub-WG has defined, I still
> do not understand the process through which the goals for the sub-WG were
> set, and how the sub-WG was formed.
>
> I also do not understand how the WG can benefit in the long run from this
> seemingly closed process where no real discussion has taken place on the
> technical merits (or lack of thereof, for what matters) of the IDs that
> were left out.
>
> Would someone please comment on this?
>
Of course!

There were enough drafts dealing with the problem presented at the last
IETF.   The authors of all of those drafts got together and came up with
some agreements about what we wanted to do about fast handoff in a meeting
outside the MIP working group meeting.  The outcome of those authors
discussions were presented to the working group and the entire working group
was asked for comment.   This is recorded in the minutes of the working
group meeting.  You can review those if you weren't at the meeting in
Pittsburgh.

Among the conclusions reached were that the WG would like to see two drafts
for fast handover - one for IPv4 and one for IPv6 - and that a design team
was being formed to look at each.

The IPv4 design team has pretty much concluded its work and is coming back
to the working group with two drafts.  (A previous post pointed to the
archive of the minutes for you to review the discussions that went on in
these meetings.)   In brief the outcome was that 3 drafts were merged into a
single draft (Calhoun, et. al.) and another draft was revised (Soliman and
El Malki).  The design team could not reach consensus on selecting just one
of these.  So it is now up to the working group to pick a single draft.   If
there are aspects of the problem that are not covered by either of the
existing drafts it is time for members of the working group to speak up.
The latest versions of both drafts have been posted.

The IPv6 design team is just about to begin its work.

It seems to me that the problem is fairly well understood, but if it becomes
apparent from the WG discussion that there is something that is being missed
it will be taken into consideration.

Hope this helps,
Phil

> Thanks
> Luca

---

From: Luca Salgarelli <[email-masked]>
Date: Tue, 3 Oct 2000 10:37:20 -0400

Hi Phil.

I was not in Pittsburgh, so your explanation is most welcome. Still, I
don't see why the sub-WG, as a basis for its work, completely ignored other
possible starting points for fast-handoffs, namely the ones based on host
based routing. In particular, I don't think there has been any technical
discussion on the WG mailing-list to justify such weeding.

Again, I asked questions about this lack of technical discussion when the
re-chartering was being discussed a few weeks ago. Apart from a message
from Charlie who said that he was not very comfortable "about disallowing
host-route based approaches for Mobile IP", there was no other reply.

And now we see that even lacking such technical discussion, we already have
selected some solutions. I would be happy to see a sub-WG working to
specify requirements, or to evaluate proposals about fast-handoffs (along
the lines of what has been done in the AAA WG). But in this case the sub-WG
was from the start ignoring solutions based on host-based routing, without
any evaluation on the technical merits of such approach.

I don't think that such a seemingly closed approach is what I would expect
from the IETF.

Thanks
Luca