Reqt. 3.1.1 [was Re: (multi6) requirements draft comments]

[Brian E Carpenter <brian@hursley.ibm.com>]

Tony Hain wrote:
...
> We also know how to
> implement a scalable metro approach, but ISPs refuse to do that. Since
> the end sites are the holders of the money, the ISPs will eventually
> loose this battle, and lacking any revolutionary technology will have to
> implement some degree of metro. My suggestion is that they do this as an
> overlay to the PA system so they get the best of both worlds.

OK, we don't discuss business models in the IETF, but this is the key
issue in moving to any kind of *fixed* address alocation other than ISP
based PA.

["fixed" is a relative term - I mean one that isn't automatically
generated on the Noel model, not one that is fixed for all time.]

The reason I've railed against Tony's PI proposal is because I have
serious doubts whether market forces will lead to the adoption
of metro (or metro-like) addressing and the consequent creation
of ISP-neutral metro exchanges. But in any case, it's something
totally outside the IETF's control. It's also completely compatible
with PA addresses, simple by giving PA blocks to the metro exchanges
if and when they appear.

However, returning to our topic, that would make the metro exchanges
key failure points in the multihoming system. That breaks
requirement 3.1.1 in the draft. Do we want to insist that the
solution MUST accommodate failure of metro exchanges?

  Brian