> I've only dealt with a handful of the bigger networks, but every transit > BGP session I've ever been the customer role on has been filtered by the > provider. From memory and in no particular order, that's UUNet, Level3, > Digex, Intermedia, Global Crossing, Genuity, Sprint, Above.net, Time > Warner, C&W, MCI, XO, Broadwing, and a few smaller ones nobody's likely to > have heard of.
There's at least one reasonably big transit provider that does *not* do prefix filtering: TeliaSonera (AS 1299). They *do* perform as-path filtering, but the effectiveness is disputable... > As an ISP providing transit, all of our customers get prefix-filtered. Same here. Steinar Haug, Nethelp consulting, [EMAIL PROTECTED]