(6bone) Ingress filtering (was: asymmetric routing)

[Dave Wilson]

> The point I am trying to make is: unless you can give me a
> legitimate reason why ISP Y should accept ISP X' PA prefix PX as
> the source, there is no reason NOT to have access-lists that deny
> customer's traffic that has a source address that not belong to the
> ISP's PA address space and is not a PI address. There are no IPv6
> PI addresses as of today. Please prove me wrong.


I agree with the above, and most of your post. One question, is it 
necessary to enumerate these reasons now, or is it sufficient to say that:

(1) There are some ISPs who do not care about asymmetric traffic
(2) There are some ISPs who may negotiate with the customer to allow it, 
as a service?

I do not propose that we require ISPs to carry asymmetric traffic. Is it 
still worthwhile to develop multihoming solutions that are available to 
those that do?

Dave