From: Michael Dillon <michael@memra.com> It really is about time that some of the larger ISP's started following the lead of folks like netaxs.com and become aggregate providers for local ISP's in their cities. This way the aggregator can be doubly and triply homed and deal with all the BGP4 nastiness. The ISP's gain the benefit of that multihoming to their city and in addition can get some of the redundancy-in-case-of-failure by buying a T1 and frame relay, or a T1 and ISDN dialup to their aggregate provider.
Every ISP wants to have a backup connection and right now most assume that multi-homing is the only way to achieve this.
I believe that a middle-tier between the ISP and the NSP is the best way to achieve this and could very well decrease global routing table size.
These are often called Metropolitan Exchanges. They have been proposed repeatedly in the IETF context. Several of them are operational around the US, but there need to be hundreds of them. How about you? Have you created one in _your_ metro? WSimpson@UMich.edu Key fingerprint = 17 40 5E 67 15 6F 31 26 DD 0D B9 9B 6A 15 2C 32 BSimpson@MorningStar.com Key fingerprint = 2E 07 23 03 C5 62 70 D3 59 B1 4F 5E 1D C2 C1 A2