Re: Routescience?

[Vadim Antonov <avg () exigengroup com>]

On Wed, 22 Aug 2001, Mike Lloyd wrote:
> The goes-inta's and goes-outa's from PathControl are all well understood
> protocols: HTTP in, BGP out.

Sounds quite dangerous.

Controlling (or zealously filtering) sources of routing information is a
necessity for any ISP which wants to offer dependable service and not live
in permanent fire-fighting mode. 

> > It's a route server whose adverts are
> > derived from empirical measurements.  No?
>
> That's a fair way to visualize what it does, yes.  
 
> How precisely we've done it, what kinds of controls we offer, how the
> reporting looks, and ultimately how much it pays off are all things we
> love to talk about, but I'm not sure this is the forum for brick by
> brick architectural inspection.  We have collected a large amount of
> data on the relevant networking effects, and come up with analyses of
> it; some of that might be appropriate at a NANOG meeting, perhaps.

My guess is that most network operations folks would be quite interested
in learning what kind of operational impact to expect from the deployment
of your boxes (and, frankly, what kind of defensive measures they have to
take to minimise the impact).

In this respect, giving the straight tecnical description is the best
thing you can do (if you believe that your technology is benigh). I hope
you understand that multihoming is always a special arrangement for ISPs,
dealt with on case-by-case basis, and many ISPs will simply refuse taking
any routes from customers unless they're convinced that customer has a
configuration which is highly unlikely to inject invalid or flapping
routes into provider's BGP.

> No doubt some folks reading this are implementing similar stuff; for
> their benefit, I'll agree with Eddy that this is indeed quite hard to do
> correctly! ;-)

What is your definition of "correctly"?  Providing benefit to this
particular customer?  Providing benefit to the entire network?  At what
cost to other customers and ISPs?  Is stable operation guaranteed or
only highly probable? Etc.

--vadim