Subject: [MEXT] Some questions on draft-sarikaya-mext-multicastdmm

From: Romain KUNTZ <[email-masked]>
Date: Fri, 22 Jul 2011 16:02:09 -0700

Hello Behcet,

I'm currently updating draft-kuntz-dmm-summary and was considering including draft-sarikaya-mext-multicastdmm. However I have a few questions about your draft.

To me it seems that your proposal is not a DMM solution by itself but is built upon draft-kassi-mobileip-dmi. Am I right? Is the exact motivation of your proposal to support multicast on the mobile node when DMI is used?

About the solution itself:

* Section 3: 

  "MN starts to receive the packets over HA-MN link from
   CN and MN starts to send packets with a destination option containing
   the previous Care-of Address as MN's Home Address (HoA) to the CN."

I'm not sure why you are doing this? This sounds like route optimization to me.

* Section 6: 
 
  "Multicast state for the mobile node is usually established when
   mobile node was on the link and the state in Multicast State mobility
   option normally must match this state and the multicast state sent by
   the mobile node becomes the multicast state of the mobile node when
   communicating over MN-HA tunnel."

This sentence is quite hard to understand. Can you explain?

Thank you,
Romain

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From: Behcet Sarikaya <[email-masked]>
Date: Sat, 23 Jul 2011 09:36:25 -0700 (PDT)

Hi Romain,
  Thanks for your mail. My replies inline.

Regards,

Behcet

> Hello Behcet,
> 
> I'm currently updating draft-kuntz-dmm-summary and was  considering including 
>draft-sarikaya-mext-multicastdmm. However I have a few  questions about your 
>draft.
> 
> To me it seems that your proposal is not a  DMM solution by itself but is built 
>upon draft-kassi-mobileip-dmi. Am I right?  Is the exact motivation of your 
>proposal to support multicast on the mobile node  when DMI is used?
> 

My draft is intended to be a candidate for Mext WG charter item on dmm and it is 
inline with the discussions we had in the last Mext session on dmm, I don't 
remember where, was it Beijing, IETF 79?
.
If you are saying that  cellular network application is emphasized, yes, I think 
that cellular networks are of course the place where we should look for 
deployment possibilities.

I think multicast support is important and so far no other draft talks about 
multicast. That's why multicast is covered in my draft.

> I'm  not sure why you are doing this? This sounds like route optimization to  

Why not? This is the behaviour MN should have because HA keeps changing, right?

>    communicating over MN-HA  tunnel."

OK, let me clarify this in the next version.

---

From: Romain KUNTZ <[email-masked]>
Date: Tue, 26 Jul 2011 16:15:42 -0700

Hello Behcet, 

Comments inline:

> deployment possibilities.

I'm not sure what made you think I was talking about cellular network application? That was not my intent. 
I was stating that if we remove the multicast part, the underlying DMM solution exposed in your draft seems to be very similar to DMI (draft-kassi-mobileip-dmi) and was wondering if there were any differences that I failed to see.

> multicast. That's why multicast is covered in my draft.

Ok.

> Why not? This is the behaviour MN should have because HA keeps changing, right?

In section 5 you are stating "This protocol removes the need for route optimization.  Correspondent nodes do not need to maintain a binding cache of bindings for other  nodes.", so this does not sound coherent with the MN behavior exposed above. 

> OK, let me clarify this in the next version.

Thanks,
romain