 when the aggregate traffic levels cause individual network elements to approach saturation. A properly calibrated usage-based pricing regime might therefore need to employ a complex version of peak-load pricing. In addition, usage-based pricing is further complicated by the fact that modern applications often access network resources autonomously, which limits end users' ability to exercise control over their total bandwidth usage. It is thus quite plausible that the transaction costs needed to establish and run a properly calibrated usage-based pricing regime would be sufficiently large to make alternative pricing arrangements economically desirable. Furthermore, even if metering is economical in the long run, the inevitable lag in creating such a metering system may lead Internet providers to rely on alternative institutional arrangements on a transitional basis. The significance of these transaction costs reveals why Internet providers might be interested in experimenting with alternative ways to manage the costs of con- gestion by forcing those who consume large amounts of bandwidth to bear the costs created their actions. 16 From this perspective, it would be quite sensible for providers to charge higher prices to those who engage in bandwidth-intensive activ- ities. If enforcement of these bandwidth limits proves too costly, it may prove more efficient to prohibit certain bandwidth-intensive applications altogether. Indeed, a close analysis of the specific provisions criticized by network neutrality propo- nents suggest that last-mile providers have experimented with tiered pricing and use restrictions in precisely the way that theory would suggest. In advancing this argument, we do not purport to draw any firm conclusions about the optimality of any particular form of tiered access or use restrictions. A determination of the most efficient institutional form would require detailed analysis of the relevant cost data and network flows and would likely vary from network to network. Indeed, one might well exp