MCB desired to level the load over their various server farms and links to
NSP-1. They had fixated on BGP as the way to do what they thought they
wanted to do, which was to affect the MED passed to peers of NSP-1 based on
loading of their servers. They also wanted to affect NSP-1's interior
routing so they could advertise more specific routes to each of their
server farms, again based on _their_ load. Several million a year in
revenues were involved.
We went through that phase with senior management in one or two of our
divisions. It's surprising how some folks interpret "It doesn't do that"
to mean "Ask me again".
IMHO, on looking at what they were trying to do, it wasn't even a routing
problem. What they wanted was probably best done with DNS load control.
Distributed Director is looking better all the time, if only they'd drop
the price down to semi-managable. *sigh*
They simply did not realize that what they wanted in routing would have
marginal effect on the direct peers of NSP-1, and none on non-adjacent AS.
Their fundamental mental model was an enterprise network where they were in
control. And their next level of detail assumed everything could be
controlled with IP routing.
Bwaahahahah but I *do* control the Internet
The concept that other traffic flowed in NSP-1, and that they could not
control the routing of other AS with whom they had no business
relationship, simply didn't penetrate.
So if the ISP has to set general policies,they need to protect themselves
against the NCBs of the world. Paranoid filtering isn't enough if the
customer is demanding something not possible. A part of making multihoming
practical is managing customer expectations and educating enterprise
network designers (or encouraging them to _have_ designers).
Good point. I really just wanted to get a combination of things across,
firstly that it's doable, and I think we probably are doing it in the most
logical way, second of all, the routing infrastructure needs to change or
routing aggragation will break, and lastly that even though it isn't
always true, it is possible that the ISP is the least "victimized" in an
But then, I think you've all got the easy jobs, since I have to deal with
most of the same issues (over 130 business units will do that), as well
as Appletalk, IPX and all the st00pid MS network garbage 
Paul "Arcserve backup is killing one of my internal 7513s" Robertson
 Yes, it's a troll, save the list follow-ups and flame directly