The only feasible solution that I've been able to come up with is to stick customer X directly on the router that peers with NSP-A and employ the use of policy routing, which would enable me to set the next hop for company X's traffic to the peering address on NSP-A.
Our NSP-A peering router is a Cisco 12016, running IOS 12.0(16)S2 and it has 256MB of DRAM.
Additionally, it is configured with NetFlow and dCEF switching.
I've never employed policy routing in this type of environment and I am concerned about the overhead that it might place on the router or on the traffic traversing the interface.
We have found that at least one version of IOS (12.0(18)S) will policy route more than you expect. When running tests in our QA lab we found that this version with policy routing and dCEF would redirect packets NOT permitted in the acl. I suggest you check your netflow records to make sure that policy routing works correctly on your version. -Hank Nussbacher Consultant Wanwall Ltd.
Jeff
catesjl9394@yahoo.com