Subject: [nemo] RE: is global HAHA so complex?

From: "Pascal Thubert \(pthubert\)" <[email-masked]>
Date: Wed, 26 Apr 2006 09:38:47 +0200

>> [Pascal] I guess that the complexity you perceive is there because
>> global HAHA goes into deployment which bears its own difficulties. I
>> suppose that to make an honest comparison, one should have the
>> equivalent level of information on the SHIM 6 alternate.
>>
>> Doing that effort, you'd find things like:
>> - to deploy a MR, you need to get a prefix from various regions into
>> each Mobile Router. This multiplies the complexity of a deployment.
>>
>
>well, managing that each local ISP injects the gloabla HAHA prefix or
>deploying a global ISP consortium seems quite complex also
>
>> - You need to deploy SHIM6 in all LFN. I agree with you that there is
>> no
>> visible time-frame for getting this.
>
>right, but you still need this to support other features like
>multihoming.
>I mean, a multihomed nemo or a nemo which home network is multihomed
>will need to have shim6 in the LFN on order to benefit from
>multihoming,

[Pascal] I fail to see why a telephone needs to be multihomed? 

And there are other things you can do than SHIM6 to benefit from
multihoming. For instance you can use MIP/NEMO to get back to ISP-B via
ISP-A. While this is hardly a generic multihoming solution, this is
acceptable when you are already in the MIP/NEMO context.

>
>> - And that gives you a very limited RO since you still do not have
the
>> proxies, which are the real reason why global HAHA improves the path.
>>
>
>not sure about this one... i mean you can use the closest HA which is
>similar to what you achieve in global HAHA (you could also expose CoAs
>to the LFN, and you would achieve optimal path, but this is other
>discussion, i guess)

[Pascal] How many prefixes do you have in your MR in the SHIM6 approach?
If you do not get rid of the home link, then that is as many anchor
points for MR to reattach. Not even one per continent. I do not call
that RO. This is why global HAHA removes the geographical constraint of
the home link.

>
>> In terms of protocol, Global HAHA introduces one new component, the
>> proxy HA. This much is not very complex. Then it changes the ND based
>> exchanges in the Home Link by a routing protocol. Again, that
>> complexity
>> is manageable.
>>
>
>In terms of protocol, shim6 does not introduces any new component,
>since the shim6 protocol is needed to support multihoming
>
[Pascal] The proxy is added to be very distributed - sort of collocated
with SGSNs type of box. This is the component that gives RO to global
HAHA. Now you see why HAHA is built that way.

>Anyway, i still argue that we need to flesh out the requirements that
>gloablly moving networks have in order to figure out which solution are
>best suited for them
>
[Pascal] Well, you were not there all the time and I personally do
welcome you now. 

But there is a long long history in NEMO about requirements (ask
Thierry). After that, we went into a long and difficult work on Problem
Statement (RO-PS). And since people had worked on RO for years, we also
compiled the RO SA, solution space analysis. 

Global HAHA builds on all that and sorry, I do not wish to start over...

Pascal

---

From: marcelo bagnulo braun <[email-masked]>
Date: Wed, 26 Apr 2006 10:56:46 +0300

> [Pascal] I fail to see why a telephone needs to be multihomed?

4G telephones are multihomed by definition. besides, the end device 
itself does need to be multihomed in order to need ths shim6 support, 
just attaching it to a multihomed network will imply multiple HoAs and 
you need something like SHIM6 to support this...

> acceptable when you are already in the MIP/NEMO context.

no, this doesn't work
multihoming is about fault tolerance and mip relies in going through 
the HA, (i guess you know this already)

So mip and nemo is not enough... so need something else for this, shim6 
or global haha for instance :-)

> [Pascal] How many prefixes do you have in your MR in the SHIM6 

shim6 relies on PA addressing, so you need one prefix per ISP serving 
the home netowrk.
This is so becasue shim6 is gloabl routing table friendly and it does 
not requires additional bgp entries

> that RO. This is why global HAHA removes the geographical constraint of

not sure what your point is here...

> Global HAHA builds on all that and sorry, I do not wish to start 

I am sorry but we are discussing rechartering at this very moment
My point is that if we are going to work on a solution we need to agree 
on the requiremetns for that solution and then define the solution. I 
don't we are ready to accept a full fleshed solution like global haha 
that implies at least a liability to the gloabl routing health without 
proper assesment of the requirements that justify the need for that 
specific solution and that other alternatives need to be ruled out.

Regards, marcelo

---

From: Alexandru Petrescu <[email-masked]>
Date: Wed, 26 Apr 2006 12:31:51 +0200

marcelo bagnulo braun wrote:
>>>> [Pascal] I guess that the complexity you perceive is there
>>>> because global HAHA goes into deployment which bears its own
>>>> difficulties. I suppose that to make an honest comparison, one
>>>> should have the equivalent level of information on the SHIM 6
>>>> alternate.
>>>> 
>>>> Doing that effort, you'd find things like: - to deploy a MR,
>>>> you need to get a prefix from various regions into each Mobile
>>>> Router. This multiplies the complexity of a deployment.
>>>> 
>>> 
>>> well, managing that each local ISP injects the gloabla HAHA
>>> prefix or deploying a global ISP consortium seems quite complex
>>> also
>>> 
>>>> - You need to deploy SHIM6 in all LFN. I agree with you that
>>>> there is no visible time-frame for getting this.
>>> 
>>> multihoming. I mean, a multihomed nemo or a nemo which home
>>> network is multihomed will need to have shim6 in the LFN on order
>>> to benefit from multihoming,
>> 
> 4G telephones are multihomed by definition.

Not only 4G, there exist at least two mass-marketed high-end 2.5G
handsets with triple interfaces: GPRS, bluetooth, wifi.  I.e. they have
multiple interfaces.  But finding what are their needs to run them
simultaneously, or routing between them is still a matter of user
requirements.

Alex

---

From: Vijay Devarapalli <[email-masked]>
Date: Wed, 26 Apr 2006 10:21:25 -0700

now I think there is confusion between site multihoming
and host multihoming.

Vijay