I called Sprint. They said to multihome, load balance across to distinct backbones (i.e Sprint & UUNET), and accept the full routing table, I'd have to use a 7000 series. I didn't believe them, so I logged a call with the TAC. They said they knew of no technical reason why the 4500 wouldn't do the trick, but maybe I should call my sales engineer. My sales engineer said the 4500 would to the trick (of course they'd prefer to sell me a 7000), but I might have to accept reduced routes or perform some other kludge to reduce the load on the router; and no telling what the performance would be like 2 months from now. Note: Our primary interest is bypassing problems we're experiencing between Sprint and UUNET via MAE-E, but we'd like to offer the best connectivity to our web servers. I called Sprint back, and they said they could work out a 'Special Customer Arrangement' to deal with the 4500. Based on the e-mail addresses I see on this group, it seems like we should be able to come to some consensus about the viability/sensibility/performance related issues related to this topology.
I'm extremely suprised that this is their stance. I'm pressed to find a technical reason behind such a requirement. The 7000 is a Motorola 68XXX based system, and the 4500/4700 is a risc based system. There have been performance tests that have shown that the 45/47 boxes out perform the 7000 boxes. I'd be very interested in hearing Sprints' reasoning on this.