Re: proposed text for charter

[Erik Nordmark <erik.nordmark@sun.com>]

Brian E Carpenter wrote:
> Well, I disagree. This may amount to asking for the
> impossible. We can properly require a shim6 implementation to
> co-exist with mobility implementations, but we cannot require it
> to operate simultaneously with them; that may turn out to be
> simply impossible. As I wrote a few days ago, it may be necessary
> to instruct shim6 to switch itelf off when some other functions
> are switched on.

While I don't have a problem with the charter not committing to solving 
this problem, I don't see it as being as hard as you think.

We have shim6, which says it will be transparent to what runs of top of 
it, be it TCP, UDP, ICMP, or anything else.

We have MIPv6, which is transparent to what runs on top of it the same way.

Thus both layering shim6 over mipv6, and layering mipv6 over shim6, 
should work in the sense that the protocol mechanisms continue to 
function. Whether either or both combinations provide a useful combined 
"service" is a different matter, but it seems to me that the shim6 
layered over mipv6 can be quite useful in the case of a mobile IPv6 node 
which has multiple home addresses, perhaps from independent home agents, 
where the shim6 overlay would could be used to create a system where a 
home agent (or the network in which the home agent resides) is not a 
single point of failure.

   Erik