Subject: [multimob] re Adoption of HO drafts incl. draft-schmidt-multimob-fmipv6-pfmipv6-multicast

From: liu dapeng <[email-masked]>
Date: Mon, 6 Aug 2012 15:28:01 +0800

Hi Thomas, Behcet and all,

please my reply inline:

-------------------------------------------
Hi Behcet, hi all,

please see inline.

On 31.07.2012 13:31, Behcet Sarikaya wrote:

We did have, apart from
draft-schmidt-multimob-fmipv6-pfmipv6-multicast, several other
multicast handover solution drafts such as:
http://tools.ietf.org/html/draft-vonhugo-multimob-cxtp-extension-01

This draft basically uses the context transfer protocol (RFC4067) to
carry multicast state between ARs/MAGs. No full handover operations
have been specified. At the unicast side, RFC4067 is a predecessor of
the more advanced Fast Handover Protocols does not apply to unicast
handover management.... IMO it does not make much sense to consider
this rather elementary approach any further.

http://tools.ietf.org/html/draft-hui-multimob-fast-handover-04

This draft is - if you want so - a competitor to
draft-schmidt-multimob-fmipv6-pfmipv6-multicast, but has never been
worked out (as have several other attempts in the past). If this
document was to be advanced, it had to rewrite (or copy ??) 80 % of
our draft, which is not a proper way to treat authorship.

===>
I aggree draft-hui-multimob-fast-handover-04 is a competitor of
draft-schmidt-multimob-fmipv6-pfmipv6-multicast.  Further more,
draft-hui-multimob-fast-handover was written in June 2009 and after
this draft was submitted for more than half a year, other similar
draft was submitted and have a lot common idea of our draft. So I
really do not see why someone say if this document was to be advanced,
it will need to "COPY" 80% of
draft-schmidt-multimob-fmipv6-pfmipv6-multicast?

To Behcet:

1. First of all, may I ask why IETF need more than one solution for
one problem?
2. If the group have decided to allow more than one WG draft forthis
problem, I then also request the group to consider
draft-hui-multimob-fast-handover-04 as one basis of WG document.

Regards,
Dapeng Liu

If we decide to accept more than one handover solution then we
probably need to consider all of them for possible WG adoption.

I don't understand your thinking here: it is perfectly normal that
there are competing approaches and the idea of the IETF discussion is
to have the best solution win. From the performance side, and from
protocol systematics (cooperation with unicast),
draft-schmidt-multimob-fmipv6-pfmipv6-multicast is clearly the best
solution for fast handover operations - this comparison includes the
adopted draft "fast handover from transient binding".
Cheers,

Thomas

--

Prof. Dr. Thomas C. Schmidt
° Hamburg University of Applied Sciences                   Berliner Tor 7 °
° Dept. Informatik, Internet Technologies Group    20099 Hamburg, Germany °
° http://www.haw-hamburg.de/inet                   Fon: +49-40-42875-8452 °
° http://www.informatik.haw-hamburg.de/~schmidt    Fax: +49-40-42875-8409 °

---

From: "Thomas C. Schmidt" <[email-masked]>
Date: Mon, 06 Aug 2012 15:03:43 -0700

Hi Dapeng Liu,

> draft-hui-multimob-fast-handover-04 as one basis of WG document.

Two answers:

  1. There may be several solutions for different scenarios on the same 
problem scope, as the unicast-people worked out several solutions (i.e., 
MIPSHOP worked out the (P)FMIPv6 handover solution and the transient 
binding in parallel.

  2. draft-hui-multimob-fast-handover-04 has never been worked out. In 
fact, it merely repeats incomplete work that has been around for years, 
the first draft with incomplete sketches on fast handover has been 
http://tools.ietf.org/html/draft-suh-mipshop-fmcast-mip6-00 in 2004!

So the argument we were presenting is: there is reason and need for this 
fast handover solution, and we should adopt the document that is most 
mature, completely worked out and discussed many times in the WG.

Cheers,

Thomas
--

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From: liu dapeng <[email-masked]>
Date: Tue, 7 Aug 2012 18:24:22 +0800

Hello Thomas,

> MIPSHOP worked out the (P)FMIPv6 handover solution and the transient

===>
Then may I ask what is the different scenarios in the PMIPv6 multicast
fast handover case?

> http://tools.ietf.org/html/draft-suh-mipshop-fmcast-mip6-00 in 2004!

==>
draft-suh-mipshop-fmcast-mip6-00  is the solution for Mobile IPv6 and
draft-hui-multimob-fast-handover is the solution for PMIP. That is
different scenario.
The author of draft-hui-multimob-fast-handover even did not noticed
that there was a mipshop draft at that time so I do not see why using
the word "repeat". But I do notice that
draft-schmidt-multimob-fmipv6-pfmipv6-multicast has a lot similarity
with draft-suh-mipshop-fmcast-mip6-00.

regards,
Dapeng

-- 

------
Best Regards,
Dapeng Liu

---

From: Marco Liebsch <[email-masked]>
Date: Tue, 7 Aug 2012 12:18:14 +0000

Just a side note: As there was already some confusion during Vancouver
meeting and the reference to the transient binding extensions (RFC6058)
still shows up repeatedly, let me clarify one thing:

PFMIP6 and Transient Binding address different use cases, they
have been specified to address different problem spaces. It's 
not appropriate to refer to these two unicast protocol extensions
in the multicast space, in particular not in the context of the
current Multimob discussion whether or not to go for one
selected or 4 protocol specifications.

marco

>-----Original Message-----
>From: [email-masked] [mailto:[email-masked]] On
>Behalf Of Thomas C. Schmidt
>Sent: Dienstag, 7. August 2012 00:04
>To: liu dapeng
>Cc: [email-masked]
>Subject: Re: [multimob] re Adoption of HO drafts incl. draft-schmidt-
>multimob-fmipv6-pfmipv6-multicast
>
>Hi Dapeng Liu,
>
>  2. draft-hui-multimob-fast-handover-04 has never been worked out. In fact,
>it merely repeats incomplete work that has been around for years, the first
>draft with incomplete sketches on fast handover has been
>So the argument we were presenting is: there is reason and need for this fast
>handover solution, and we should adopt the document that is most mature,
>completely worked out and discussed many times in the WG.
>
>Cheers,
>
>Thomas
>--
>
>_______________________________________________
>multimob mailing list
>[email-masked]
>https://www.ietf.org/mailman/listinfo/multimob

---

From: "Thomas C. Schmidt" <[email-masked]>
Date: Tue, 07 Aug 2012 22:16:18 +0200

Hi Marco,

in general I agree: the discussion on fast handover solutions has 
somewhat gotten out of hand.

Regarding RFCs 6058 vers. 5568/5949: I didn't mean to say they do the 
same - still use cases appear very similar. More precisely from the 
documents:

   * 5568/5949: "improve handover latency"

   * 6058: "ensures optimized forwarding of [...] packets"

Maybe you can clarify the differences?

Otherwise, the subject of the debate is the adoption call of 
draft-schmidt-multimob-fmipv6-pfmipv6-multicast. In a previous, detailed 
offline discussion you were supporting the adoption of both drafts 
(draft-contreras-multimob-rams and 
draft-schmidt-multimob-fmipv6-pfmipv6-multicast).

Maybe you can clarify, as well?

Cheers,

Thomas

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