From: Travis Pugh [mailto:tpugh@shore.net] Sent: Tuesday, April 03, 2001 10:34 AM
I'm at a multi-POP network in Boston. We've had great luck selling customers a Verizon circuit into one of our POPs and a Worldcom circuit into a different one. It costs more, but they don't have nearly the exposure of a single circuit customer. However, if you're not set up to do this, the appropriate level of paranoia calls for circuits to two different providers. Maybe if SPs really addressed availability requirements of their customers, it wouldn't be such an issue.
The problem with this, if done, is that we back right into the other problem of prefix filtering. If the customer has a /19 or /20, there is generally no problem. But, if it is the usual case (/24) then only one of the upstreams can aggragate the routes up. What is the other ISP to do? How would this be made to work? BTW, this is exactly the reason we weren't fully multi-homed yet. Yes, greg described a way where both interfaces (end point) were NAT'd. However, I have a concern with brittleness and tinker-factor there.