ard. As consumer preferences become increasingly heterogeneous, one would expect the optimal number of net- works to begin to exceed one. By artificially limiting nonstandardization, platform access can prevent the network from reaching the optimal level of standardization. Platform access is also subject to a number of practical problems. Once the gov- ernment designates a standard, network owners cannot implement any changes to that standard until the government has approved those changes. Imposing platform access thus inevitably causes a degree of delay in the speed with which the network can adapt to changes in technology. In addition, platform access requires the gov- ernment to designate particular locations within the network where platform access can occur. The logical course of action is for the government to choose locations at natural interfaces between different segments of the industry. The problem is that technological change can cause natural interfaces to shift or to collapse altogether. Such problems are likely to loom particularly large in industries such as broadband that are undergoing rapid technological change. Consider the transformation that occurs when end users shift from narrow- band, in which end users are reached through dial-up services, to broadband con- nections such as DSL or cable modem service. Long-haul transmission is provided by backbones, which provide high-speed connections among a dozen or SO network access points located at key locations throughout the country. Under a narrowband architecture, end users connected to the Internet through their local telephone system, which routed Internet-bound calls to locations in individual cities spread throughout the country in the same manner that it routed conventional telephone calls. The local telephone company did not need to maintain any packet-switching capability of its own. The only difference between Internet-bound calls and con- ventional calls was that the former consisted of data packets encoded in an analog format by the