Some of the bigger, well-funded ISPs started making architectural changes in their networks a few years ago to minimize the bottlenecks that exist at the network exchange points where Internet traffic is handed off from one carrier to another. Packet loss, not bandwidth, is the big enemy of Internet performance, says PSINet's Chuck Davin, chief technology officer. Routers that send packets from one network to another are in no man's land, he says, a little piece of the network that no one is responsible for. The trick is to reduce the number of routers the data goes through. Fewer router transfers means fewer chances of losing a packet.
PSI says other services have followed suit since then.
But many providers hooked up to the network exchange points don't understand the packet loss problem, Davin says. For example, telephone companies are used to engineering voice networks, where adding a bigger pipe is generally the way to fix a problem. But bandwidth has nothing to do with packet loss, he says. The biggest Internet backbone providers have started exchanging traffic directly with each other to avoid the crowded peering points altogether. By exchanging traffic directly, the biggest carriers free up the peering points for the smaller carriers.