Subject: RE: [mobile-ip] Re: HAO and BE processing will be mandated

From: [email-masked]
Date: Mon, 22 Jul 2002 12:16:12 -0500

>Michael Thomas wrote: 
>>    Frankly, I don't think that there is any evidence 
>>    that the net would be substantially harmed if RO 
>>    wasn't widely implemented and/or enabled. Indeed, 
>>    I think  there's good reason to believe that many/most 
>>    nodes will not enable RO even if their kernel 
>>    implements it. In some cases, it's likely to be 
>>    a nice and useful optimization, but I really 
>>    don't see it as a "if we don't do this the net 
>>    will fall apart". As such, SHOULD seems like it 
>>    strikes the right balance. 
>> 
>>              Mike 
>> 
>
>I could not agree more with this point. RO would be a required 
>functionality a number of years back, when the net was in it's 
>infancy and bandwidth availability in the backbone networks 
>(even transoceanic links) were severely limited. 
>We are in the age of OC-192/768s over DWDM. The delay that an IP 
>packet incurs in the core is almost negligible. 
>If bottleneck in the HA is the primary driver for RO, then it is 
>possible to solve the problem with load balancing with DHAAD. 
>
>My two cents. 
 
RO gives you the capability of having two end-points connected without
having to rely on intermediate nodes such as the HA being
involved. The HA is not the bottleneck. One of the benefits of RO is
lesser traffic in the backbone and to a certain degree reduced
latency. But these are some of the lesser motivations. 
 
Having a mobile anchored at some point in the network (HA) when it is
non-essential is just not the right approach. Mandating HAO processing
in all IPv6 nodes is the only way to accomplish this and reverse
tunnelling or having a node anchored at the HA is an option only for
backward compatibility to the nodes that already deployed (which is a
pretty small percentage of IP nodes).
 
>Regards, 
>Kuntal 
 
-Basavaraj

---

From: Jari Arkko <[email-masked]>
Date: Tue, 23 Jul 2002 11:44:47 +0300

> latency. But these are some of the lesser motivations.

Well, I think latency is still a very good motivation. Even if we
upgraded the backbone, someone forgot to upgrade speed of light ;-)

> non-essential is just not the right approach.

I agree.

> Mandating HAO processing

Please remember that the HAO processing is not sufficient by itself.
This whole debate is not really about RO and HAO processing -- currently
the spec is NOT mandating that with any keyword, we are expecting the
node requirements document to do that. However, we are mandating the
combination of IPsec, triangular routing, and HAO processing. So, when
you are saying "mandating HAO processing", do you IPsec+triangular+HAO
combination?

I would actually say that RR, RO, and HAO are really the main ingredients
for a successful mobility solution. The other combination is really just
a special case and I can't see it being used in the Internet for any
sizeable fraction of traffic. In fact, in my code I would always do RO
even if I had an IPsec SA, so the combination might not even be usable
by everyone.

Jari