[c-nsp] load balance with resiliency

[Nick Kraal]

Dear all,

To verify some thoughts. Anyone have a good idea on how to load balance 
with resiliency between multiple circuits to 2 customer managed routers 
(CMR) and to one single ISP router (ISPR):


   4x STM4
      |
     ???
  CMR1  CMR2
   |     |
  --------
  | ISPR |
  --------

Between CMR1/2 with the ISPR, eBGP local preference would be used over 
STM16 links. Traffic would be one the subscribed STM16 port, and 
automagically switch to the other STM16 link if say, CMR1 crashed big time.

So then what would be the best way then to load balance the single STM4 
circuits, maintain resiliency, and have maximum throughput if either the 
STM4 circuits are down or any one of the CMRs is out of action.

Any ideas? I am thinking of 1 pair of STM4 on each CMR. What sort of BGP 
advertised/received policies should be employed?

Thanks in advance!

-nick/