If we're talking about networks with that kind of MRC, is it really that far of a stretch to require PI space for this? Then again: If we're talking about that kind of MRC, then I'm assuming ISP A can be coaxed to allow explicit and well-defined exceptions on the customer's links.
Yes. A) Check the prices for PI space, if you can even get any. B) Our network works fine with PA space. If you claim otherwise, we know plenty of other operators who aren't as wedged as you are. Trying to solve technical problems with social solutions rarely works. See for example, the sad history of passwords. Regards, John Levine, johnl@iecc.com, Primary Perpetrator of "The Internet for Dummies", Please consider the environment before reading this e-mail. https://jl.ly