Subject: [nemo] RE: About route aggregation in global HAHA

From: "Pascal Thubert \(pthubert\)" <[email-masked]>
Date: Tue, 11 Apr 2006 10:10:25 +0200

Hi:

We have seen a lot of great arguments in this list in the recent days
about whether and how global HAHA could / would be deployed. I need to
revisit it all and add things to the draft.

Nevertheless, here's what I gathered:

- Some assumptions lead to aggregation trouble at BGP level. Those
assumptions are based on the way the prefixes are distributed to the
Service providers today. Mobile prefixes might not necessarily be
distributed in that same fashion, though. They could be shared.

- We need to work out the conditions to make the protocol deployable. If
this involves revisiting some assumptions about IPv6 deployment, then
that part goes beyond the scope of NEMO and has to do with either IPv6
or IPv6 Ops. 

- The NEMO part for this discussion is enabling Route optimization
within the infrastructure. There are a number of use cases to sustain
the need. IP mobile telephony (4G?) is an example, where Service
Providers do not necessarily wish to have the phone perform the RO
themselves.

- Global HAHA introduce proxy HAs which enable this route optimization
with a trust model in place. I'd say that defining how that works is
enough work for NEMO; whereas proposing the deployment model should be a
request from us to other WGs.

Let me give you an example. Say that 3-4 ISPs from different continents
form a mobile ISP consortium. 

That consortium obtains a short prefix from one of the NICs, call it the
mobile prefix. Internally, the consortium shares that addressing space
between members, leaving big chunks free for new comers. The rule is
that only the big aggregation is redistributed over the Internet BGP,
from most POP of members ISPs. But internally, the consortium of service
providers runs a second BGP which deals with the subnetting of mobile
prefix, over a mesh of tunnels and private links. 

A similar mesh has formed already in the GPRS core network. On top of
that model, Global HAHA introduces a Route Optimization scheme that does
not exist between SGSNs, and integrates voice and data.

Pascal

---

From: marcelo bagnulo braun <[email-masked]>
Date: Tue, 11 Apr 2006 13:50:35 +0300

Hi Pascal,

I have two points that i would like to address as reply to your note:

First, a broader topic about RO and  global HAHA as a route 
optimization mechanism.

> request from us to other WGs.

IMHO, we should first decide on which forms of RO for nemo are we going 
to work on, and then move on to specific solutions.

I mean, as specified in the RO taxonomy draft there are several and 
very different approaches to RO. I think that in order to do the 
charter for future work, we need first to decide which one of the RO 
approaches are we going to work on.

However, the proposed charter only has Global HAHA as a RO solution for 
nemo, so it seems to imply that this is the RO that we have selected.
I would propose to open the general discussion about which RO 
approaches are we going to work on first rather than focussing in if we 
are going to work on global haha or not...

Second, a more focussed issue with respect to routing system 
scalability and business model

> prefix, over a mesh of tunnels and private links.

but this seems to be complettelly different that what other people have 
been claiming here on the list.
Past comments have strongly argued that global mobile network need PI 
addressing and global HAHA seemed a mechanisms to provide access to 
this PI prefix that the airline company gets.

This is completelly different than the mobile ISP model that you are 
suggesting.

What worries me is that i don't see any mobile ISP in the list claiming 
that they need global HAHA to deploy their business, but there are end 
users (air companies) that claim that want PI addressing for deploying 
this.

Regards, marcelo

---

From: Keiichi SHIMA <[email-masked]>
Date: Tue, 11 Apr 2006 20:56:18 +0900 (JST)

Hello,

From: marcelo bagnulo braun <[email-masked]>
Subject: About the proposed charter and global HAHA (was Re: [nemo] RE: About route aggregation in global HAHA
Date: Tue, 11 Apr 2006 13:50:35 +0300

> this PI prefix that the airline company gets.

I think, in the proposal from Pascal, "a short prefix from one of the NICs"
is the equivalent of the PI address.

I believe what they need is a network which has a fixed prefix and
provides low-latency communication to the rest of the Internet, not PI
addresses.  If the global HA-HA provides the same features, then there
will be no problem.  (Although I still don't understand the global
hA-HA completely)

I'm afraid many people don't understand what the global HA-HA can
provide (including me).
 
> users (air companies) that claim that want PI addressing for deploying 

That is because many people think only PI addresses can provide what
airline companies need.  If we understand the global HA-HA can provide
the same things, maybe we can compare them, I think.

Regards,
---
Keiichi SHIMA
IIJ Research Laboratory <[email-masked]>
WIDE Project <[email-masked]>

---

From: marcelo bagnulo braun <[email-masked]>
Date: Tue, 11 Apr 2006 15:06:40 +0300

El 11/04/2006, a las 14:56, Keiichi SHIMA escribió:

> Subject: About the proposed charter and global HAHA (was Re: [nemo] 
> RE: About route aggregation in global HAHA

not really, because PI means that is not related to the provider. So 
the number of PI prefixes that you need in the global table grows 
linearly with the number of end sites that are needing it
However, in the case of the PA or the mobile ISP that Pascal is 
suggesting, many end sites can use the services of a single mobile ISP 
and then the number of entries required in the global BGP table grows 
with the number of mobile ISP (in other words, it scales much better 
than the case of PI prefixes)

So, a mobile ISP could serve many airlines and still be announcing a 
single prefix in the DFZ, while if the PI approach is followed, then 
the number of prefixes announced in the dfz is proportional to the 
number of airlines.

regards, marcelo

---

From: Vijay Devarapalli <[email-masked]>
Date: Wed, 19 Apr 2006 14:59:22 -0700

hi Marcelo,

first, I apologize for disappearing from the list
for a while.

marcelo bagnulo braun wrote:
> I would propose to open the general discussion about which RO approaches 
> are we going to work on first rather than focussing in if we are going 
> to work on global haha or not...

there is some misunderstanding. there was never a
proposal to make Global HAHA as _the_ RO solution for
NEMO. there was going to be a separate work item on a
general RO solution for NEMO that does not involve
multiple home agents. perhaps TJ or Thierry could
comment on this.

Vijay

> 
> 
> Second, a more focussed issue with respect to routing system scalability 
> and business model
> 
> you stated that:
> 
> addressing and global HAHA seemed a mechanisms to provide access to this 
> PI prefix that the airline company gets.
>

---

From: Vijay Devarapalli <[email-masked]>
Date: Wed, 19 Apr 2006 15:03:54 -0700

> PI prefix that the airline company gets.

well, your home prefix, along with the set of mobile
network prefixes is a set of PI addresses. as long
as the distributed set of home agents let the mobile
network keep the same home address and mobile network
prefix while providing mobility, you have a solution.

Vijay

---

From: marcelo bagnulo braun <[email-masked]>
Date: Thu, 20 Apr 2006 09:32:19 +0300

El 20/04/2006, a las 1:03, Vijay Devarapalli escribió:

>> but this seems to be complettelly different that what other people 
>> have been claiming here on the list.

yes, so the contribution of this solution to the global routing table 
would be one entry per home prefix

Regards, marcelo

---

From: Vijay Devarapalli <[email-masked]>
Date: Thu, 20 Apr 2006 10:26:12 -0700

> would be one entry per home prefix

since global HAHA is not a generic route optimization
solution, and not many deployments can actually have
distributed home agents, it shouldn't be a concern for
now.

Vijay

---

From: marcelo bagnulo braun <[email-masked]>
Date: Fri, 21 Apr 2006 09:59:22 +0300

> distributed home agents, it shouldn't be a concern for

but if inflight internet access becomes a comodity (and i think it may) 
then all airlines and ships may want to have access to this technology, 
i am afraid, so i am not ready to dismiss the effect of this in the 
global routing table so easily...

I am more convinced by the argument that there are some deployment 
models that achieve route aggregation (Pascal's mobile ISP argument) 
than by the expected reduced number of users, but still, i am far from 
easy with this...

regards, marcelo

---

From: Alexandru Petrescu <[email-masked]>
Date: Fri, 21 Apr 2006 12:12:28 +0200

Vijay Devarapalli wrote:
>>>> Past comments have strongly argued that global mobile network need 
>>>> PI addressing and global HAHA seemed a mechanisms to provide access 
>>>> to this PI prefix that the airline company gets.
>>>
> solution,

What is global HAHA for if not for shortening paths?  Isn't its main 
goal to "use a HA that is closer to MR"?

Alex

---

From: Vijay Devarapalli <[email-masked]>
Date: Fri, 21 Apr 2006 12:02:13 -0700

> goal to "use a HA that is closer to MR"?

global HAHA can do some sort of route optimization.
but we didn't start working on it to solve the
route optimization problem. the history goes some
thing like this

1. we needed a solution where multiple home agents
on the same home link can share the binding cache.
this was first mentioned four years ago when the 'S'
bit in the binding update was being discussed in the
Mobile IP working group.
2. then there was a need for load balancing, HA
reliability, etc... so we came up with local HAHA
3. now that multiple home agents can serve the same
home prefix, we took the concept further and said
the home agents can actually be geographically
distributed
4. then we heard about the Boeing problem from Terry
Davis. thats when we extended HAHA to address mobile
networks on airplanes. I am not saying it addresses
it completely. its possible that global HAHA sucks
at solving the mobile networks on airplanes problem.
Pascal would know more about this.

so thats the history.

it can be used for route optimization, but can't be
standardized as _the_ route optimization solution
since it is not realistic to assume that every
operator would be able to deploy distributed home
agents.

Vijay

---

From: Alexandru Petrescu <[email-masked]>
Date: Sun, 23 Apr 2006 20:32:42 +0200

> bit in the binding update was being discussed in the

I agree with this need and DHAAD method.  The HAs stay on the same link.

> reliability, etc... so we came up with local HAHA

Any method to separate HAs to _different_ links, i.e. a router between 
two HAs serving same HoA, makes very little sense.  Be it local or 
global.  If one can do that (two different HAs separated by one or more 
routers, the HAs serving a unique Home Address) then one does not need 
Mobile IP.

> the home agents can actually be geographically

Which is not feasible.  Could be drawn on paper but not implemented.

> Pascal would know more about this.

Thanks for explaining the conceptual evolution of it.

> operator would be able to deploy distributed home

Ok,

Alex

---

From: Vijay Devarapalli <[email-masked]>
Date: Sun, 23 Apr 2006 15:21:50 -0700

> routers, the HAs serving a unique Home Address) then one does not need 

I would re-word to say "it can be done without
using Mobile IP". sure, I agree with that. consider
this as another approach.

> Which is not feasible.  Could be drawn on paper but not implemented.

disagree.

Vijay