There are two good reasons to peer only with backbones of comparable size: 1) technical -- this allows to do hot-potato routing with minimal resulting delay assymetry 2) economical -- peering at IXP is favouring smaller folks in cost/benefit game. For a large ISP the percentage of additional destinations the small ISP offers is smaller, and so is the benefit of peering. ANd extra peerings are far from "free". They produce extra paths which need to be processed by routers, and so translate in shorter lifetime of the equipment -- which means very real money. It also reduces effectiveness of aggregation and increases risk of catastrophic failures (large ISPs spend significant part of engineering resources and practice rather strict controls on configuration process to ensure sanity of routing; they also have to _trust_ each other. Most of garbadge in routing tables comes from small ISPs, and is usually hard to fix (no 24hr NOC etc). So the "three IXPs" limitation is specifically designed to ensure equality of sizes (to a some extent), other provisions of BLIAs ("blia" is a common profanity in Russian, btw :) include 24hr NOC etc. Thus, far from being anti-competitive restrictions those policies only serve to level the playing field -- as players who skip investment in infrastructure, engineering and operations would get unfair advantage otherwise. No sane NSP would refuse peering with a new nationwide DS-3 backbone -- providing that it is something more than hot air. The plank is going to be raised to OC-3 pretty soon, though.... --vadim