Jonas, Jonas Luster wrote:
* Sean Finn sez:
The RouteScience PathControl product which was announced today
- supports active and/or passive measurements
What does that mean in 'non-buzzword' speak? In other words, if you'd talk to someone who's actually seen a router at one or two occassions, what would you tell him/her?
A quick description is that PathControl optimizes the BGP decisions for a multihomed organization. It passively measures performance over all egress paths, in a manner described below. If active measurement to selected destinations is required, it can be configured, but we view that as strictly a supplemental source of data. An organization would only actively probe endpoints who agree to such exchange; typically, that might involve remote offices or B2B partners. (Ideally, one PathControl would talk to another.) Bottom line: PathControl does not automatically send unsolicited test packets to anyone.
Is this YAPM (yeat another ping misuse), ROTEG (route optimization through esoteric guessing) or something completely new such as (cough) Gibsons 'nano-probes'?
IMHO, it's NOTA. (None Of The Above); but a more detailed description is called for ...
So, if I am, say, yBay, a large used panties and fake celebrity autograph auction house, how would I, given the diversity of my clients, do any optimization?
The details of the measurement method were written up in Network World yesterday; see http://www.nwfusion.com/edge/news/2001/0820routescience.html In short, the PathControl device serves a component of HTML content, and by watching the detailed TCP behavior, it gains information on the end to end latency and loss characteristics of every path out of the organization. The measurements are tailored to the NLRIs an organization actually uses. We find that this greatly cuts down the number of updates we must send to deliver effective results. Few "stub" organizations talk to even 10% or 20% of the full table at a time. PathControl then offers advice in the form of BGP updates to the edge routers. The prefixes, the rate of change and the factors to optimize can be constrained, between CLI commands on PathControl and the conventional filtering offered within BGP on the edge routers. (FWIW, PathControl marks any updates it sends with NO-EXPORT, as one more part of ensuring that the changes are not propagated outside the AS.) Obviously, I'd be more than happy to discuss this further; off-list may be a better context for any really detailed conversation. Mike Lloyd CTO, RouteScience