Shim6, was: Re: filtering /48 is going to be necessary

Thu Mar 15 23:31:07 UTC 2012

William Herrin wrote:

>> A difficulty to understand the end to end principle is to
>> properly recognize ends.
>>
>> Here, you failed to recognize home agents as the essential
>> ends to support reliable communication to mobile hosts.
> 
> A device which relays IP packets is not an endpoint, it's a router.

If you want to call something which may not participate in
routing protocol exchanges a router, that's fine, it's your
terminology.

But, as far as HA has "the knowledge" obtained through
control packet exchanges with MH, it is the end that can
give "the help" to make mobile IP correct and complete.

> It
> may or may not be a worthy part of a network architecture but it is
> unambiguously not an endpoint.

Even ordinary routers are ends w.r.t. routing protocols, though
they also behave as intermediate systems to other routers.

As LS requires less intelligence than DV, it converges faster.

> If that isn't clear to you then don't presume to lecture me about the
> end to end principle.

Here is an exercise for you insisting on DNS, an intermediate
system.

	What if DNS servers, including root ones, are mobile?

						Masataka Ohta