Peering versus Transit

  Hi Bill,

> I can see no justification under any circumstances why any provider
> would refuse to peer with another at an established exchange point for
> exchanging their _own_ customers' traffic!

  I can give you three:

     1/ LargeISP does not want to spend the X hours it takes to
    bring up a peering session for SmallISP's routes. The
    benefit gained to SmallISP's 5 routes is not great enough.


1a/ LargeISP realises adding another peer adds to router load,
  both in the sense of running more BGP sessions and increasing
  memory load as if LargeISP is already seeing these routes
  somehow he has to keep yet another path.

1b/ Large ISP does not want the administrative burden of keeping
  another peer active when they get little perceived benefit
  from the peering session (more people to contact if they
  change router config etc.)

Note that for most of Europe (not currently true in Demon's case)
the traffic would otherwise go through icp/icm and Sprint gets
paid in the end for this. So it is somewhat ironic that Sprints
larger competitors would rather pay Sprint than peer with
European providers.

Peter is thus quite right that it is not sensible (IMHO) to use
exactly the same peering criteria for US and international

Peter - Re Sprint - this may have something to do with the fact
it is not too long since Demon were a Sprint customer. Ditto AGIS.

Alex Bligh
Xara Networks