ect different networks to pur- sue different pricing strategies. In addition, the data would need to be updated constantly in response to technological changes. The difficulties in determining the relative merits of various forms of access tiering and end user restrictions provide one of the most powerful arguments against mandating or foreclosing any particular institutional arrangement. The plausibility of economic benefits provides sufficient justification for permitting network owners to experiment 16 The most systematic review of these types of restrictions is Wu (2003). For less comprehensive surveys, see Saltzer (1999); Bar et al. (2000); Lessig (2002). Networks in Telecommunications with different pricing arrangements until actual harm to competition can be demonstrated. 1. Prohibitions on Reselling Bandwidth or Acting as an Internet Service Provider Consider first restrictions on reselling bandwidth, acting as an ISP, or attach- ing equipment that makes network service available to users residing outside the subscriber's premises. When analyzed under the framework laid out above, such restrictions make perfect sense. A last-mile provider who finds that transaction costs render deploying usage-based pricing uneconomical may find it beneficial to turn to a flat-rate price set equal to average congestion costs imposed by an average user. Even though such usage would be unmetered at the margin, the flat-rate price could be calibrated to lead to an equilibrium that approached efficient pricing. Reselling bandwidth or acting as an ISP would upset this balance by having a single connection serve multiple end users, despite the fact that the cost of service was calibrated to reflect the network demands imposed by a single user. This would in turn create economic inefficiency by allowing those end users to impose congestion costs that far exceed the amount that they pay for the service. Prohibiting end users reselling bandwidth or acting as ISPs would thus appear necessary to facilitate flat-rate pricing. 2. Rest