For example, Internet traffic has grown from a mere 45 web connections in October 1992 to more than ten million last month, Paxson notes. One of the biggest problems with the Internet today is congestion. The net's worst problem, however, also reflects one of its main strengths. The myriad of data connections in the network all share the available capacity among them, rather than reserving capacity individually, as do telephone connections. This sharing makes for a much more efficient use of the network, but it also leads to traffic overload.
Links go down all the time and packets have to be re-routed, which happens automatically.
The underlying problem is that the web, a huge hypertext database, is poorly designed to run on the global Internet, Paxson says. As the popularity of the web grows, the problems loom ever larger. We can build systems with hundreds of things and they work fine, but when we scale them up to hundreds of thousands, they break down, and it's hard to predict where they will fail. Users may have the perception that something is overloaded when it's actually misengineered. Without measurement, it can be impossible to tell where the problem lies.