Subject: RE: [nemo] RE: splitting moving networks (was: DND test)

From: "Soliman Hesham" <[email-masked]>
Date: Thu, 25 Mar 2004 09:14:03 -0500

Alex, 

I was giving a scenario that purposely eliminates 
irrelevant information to focus on the key issue. 

 > Hesham, please just say how many MR's exactly (instead of 
 > "more than one
 > MR") 

=> It doesn't matter for my scenario. If you need
a number 2 is fine.

    and how many and what kinds of interfaces. 

=> Doesn't matter what kinds of interfaces, cellular/WLAN
pick one.

    Please say 
 > "with other
 > LFN's" instead of "with or without other MNN's/LFN's".  

=> The MR can move with an LFN (or more), with an MNN (or more),
or a mix of both.

 >  > => The scenarios draft can help.

=> We need a multihoming scenarios draft, I think
there is a number of people working on it. I don't 
know if it's published yet. But this :

http://www.mobilenetworks.org/nemo/drafts/draft-multihoming-generic-goals-and
-benefits-00.txt

is a start.

Hesham

 > 
 > Which scenarios draft?  Which of these:
 > 
 > http://www.mobilenetworks.org/nemo/drafts/draft-ietf-nemo-req
uirements-02.txt
http://www.mobilenetworks.org/nemo/drafts/draft-ietf-nemo-terminology-01.txt
http://www.mobilenetworks.org/nemo/drafts/draft-lach-nemo-experiments-overdri
ve-01.txt
http://www.mobilenetworks.org/nemo/drafts/draft-wakikawa-mip6-nemo-haha-01.tx
t
http://www.mobilenetworks.org/nemo/drafts/draft-charbon-nemo-multihoming-eval
uation-00.txt

Or is it a new draft that has not yet been published?

Alex

---

From: Alexandru Petrescu <[email-masked]>
Date: Thu, 25 Mar 2004 21:29:07 +0100

Soliman Hesham wrote:
> => It doesn't matter for my scenario. If you need a number 2 is fine.
 >
> => Doesn't matter what kinds of interfaces, cellular/WLAN pick one.
> 
> Please say
>> "with other LFN's" instead of "with or without other MNN's/LFN's".
>
> => The MR can move with an LFN (or more), with an MNN (or more), or a
> mix of both.

Thanks for the first two details. I've built a scenario with two MR's
and two HA's and two LFN's. First they are home, and then half of the
moving network moves outside the home link.

In the picture below, both MR1 and MR2 are connected to their home link,
which is a common link. MR1 is served by HA1 and MR2 by HA2 when they're
not at home. There are two MNP's on the same moving network link. LFN1
configures its default route to go to MR1 and LFN2 its default route to
go to MR2 (this could be done manually routes, or with some security
features, or with virtual VLAN or with other L2 technique, or otherwise,
but not NEMO stuff).

HA1 and HA2 are connected to the same home link but do not maintain a HA
list between them since they serve different MNP's;

     ----    ----
    | HA1|  | HA2|
     ----    ----
       |       |       ----
   -------------------| BR |------> Internet
       |       |       ----
     ----    -----
    | MR1|  | MR2 |
     ----    -----
       |       |
       ----------moving network
       |       |
     ----    -----
    |LFN1|  |LFN2 |
     ----    -----

Now the sub-segment made by MR2 and LFN2 physically splits from the
moving network and becomes a moving network on its own, and goes under
AR, in the picture below. After obtaining CoA, MR2 maintains a tunnel to
HA2.

     ----    ----
    | HA1|  | HA2|                        /
     ----    ----              ----------/
       |       |       ----   |          |
   -------------------| BR |--| Internet |
       |               ----   |          |
     ----                      ----------\
    | MR1|                                \
     ----                     		  \   ----  Visited link
       |                      		   --| AR |------
     -----half moving net        	      ----     |
       |                      		               |
     ----                     		             ----
    |LFN1|                    		            | MR2|
     ----                     		             ----
					               |
				     half moving net ----
                                                        |
                                                      -----
						    | LFN2|
						     -----

I think in this configuration all works fine from the NEMO standpoint. 
I think the potential problem may lie in how LFN's configure different 
default routes; this can be done at least manually and I think that how 
this is done is outside the scope of NEMO.

So, what do you think, am I missing something?  Is anything from the 
NEMO Base Support that forbids this kind of split moving networks 
configuration to work properly?

Alex

---

From: Alexandru Petrescu <[email-masked]>
Date: Thu, 25 Mar 2004 21:29:07 +0100

----    ----
    | HA1|  | HA2|
     ----    ----
       |       |       ----

     ----    ----
    | HA1|  | HA2|                        /
     ----    ----              ----------/
       |       |       ----   |          |

Alex

---

From: Thierry Ernst <[email-masked]>
Date: Fri, 26 Mar 2004 12:50:26 +0900

A precision.

> http://www.mobilenetworks.org/nemo/drafts/draft-multihoming-generic-goals-and

Version -00 has been plublished, version -01 is pending (sometimes in April). 

Well, this draft is, as its names stand for, "generic", i.e. not
relevant to particular NEMO issues.  So, I think the new WG
draft-ietf-nemo-multihoming-problem-statement under course (based on
draft-ng-nemo) would be the starting doc.

Thierry.

---

From: Thierry Ernst <[email-masked]>
Date: Fri, 26 Mar 2004 12:50:26 +0900

A precision.

Thierry.

---

From: "marcelo bagnulo" <[email-masked]>
Date: Fri, 26 Mar 2004 11:51:23 +0100

>    -------------------| BR |------> Internet

Question, does the MR2 and MR1 register the same prefix or different
prefixes?
Do the MNN have one or two prefixes?
If they have one, how do you know whether to forward packets to HA1 or to
HA2 when they are split?
If they have 2 prefixes, hpw does this works when the network is not split
but one of the MR is down? Note that if MNN only can use one MR with its
correspondent prefix, this is not really one NEMO, but two nemos moving
together, i guess.

Regards, marcelo

---

From: "marcelo bagnulo" <[email-masked]>
Date: Fri, 26 Mar 2004 11:51:23 +0100

Regards, marcelo

---

From: Alexandru Petrescu <[email-masked]>
Date: Fri, 26 Mar 2004 15:37:18 +0100

marcelo bagnulo wrote:
>> I think in this configuration all works fine from the NEMO
>> standpoint. I think the potential problem may lie in how LFN's
>> configure different default routes; this can be done at least
>> manually and I think that how this is done is outside the scope of
>> NEMO.
> 

MR1 and MR2 register different MNP's to their respective HA.

> Do the MNN have one or two prefixes?

In this scenario there's only LFN and each LFN autoconfigures an address 
from the respective MNP.

> If they have one, how do you know whether to forward packets to HA1
> or to HA2 when they are split?

I do not see why there should be one MNP.  If the goal is to support 
"split" moving networks then just use two MNP's.

> but one of the MR is down?

If one MR1 is down then LFN1 does not get packets.  If one wants to have 
LFN1 still get the packets when MR1 is down then there should be a means 
to do it.  Just tell me that means (keeping both MR's at home) and I'm 
going to try to see how it works when MR's leave the home.

> Note that if MNN only can use one MR with its correspondent prefix,
> this is not really one NEMO, but two nemos moving together, i guess.

Yes, there are two moving networks two MNP's two Mobile Routers; it is
configured in such a way to be able to be split, is there anything wrong
with this?

Alex

---

From: Alexandru Petrescu <[email-masked]>
Date: Fri, 26 Mar 2004 15:37:18 +0100

Alex

---

From: "marcelo bagnulo" <[email-masked]>
Date: Sun, 28 Mar 2004 14:14:18 +0200

> configured in such a way to be able to be split, is there anything wrong

No, there is nothing wrong, it is just that this configuration hardly
provides any multihoming benefit.

I guess that i was thinking in a network with multiple MRs, that provides
multihomed benefits and that can split.

Regards, marcelo

---

From: "marcelo bagnulo" <[email-masked]>
Date: Sun, 28 Mar 2004 14:14:18 +0200

Regards, marcelo