n Co., 419 U.S. 345, 353 (1974), applying the same reasoning in the context of a public utility's refusal to serve a customer. Antitrust as Applied to Network Industries The collapse of the conceptual foundation for the common law duty to serve essentially eviscerated it as a basis for judicial imposition of retail access to telecom- munications networks. 2. Wholesale Access Wholesale access is a right given to a network owner's competitors to resell the network's services to end users. As is the case with retail access, under wholesale access the network's elements are kept together and purchased as a whole except for certain retail merchant activities. The key distinction is that in retail access, access is provided to the customer, whereas in wholesale access, access is provided to a competitor. Wholesale access has two primary effects. First, it changes the overall demand of the network, which in turn changes its cost, capacity, reliability, and optimal config- uration. Wholesale access thus confronts network owners with the same quandary as retail access, complicated still further by the fact that market demand now depends on two prices - the price of wholesale access and the price of retail service - rather than just one. The existence of two prices makes the net impact on demand ambiguous. To the extent that wholesale access carries with it a nondiscrimination mandate, it can also prevent network owners from using price discrimination to minimize welfare losses. Second, wholesale access takes the marketing functions outside the boundaries of the firm. Forcing the externalization of functions is problematic from the stand- point of the theory of the firm because it forces the network to deviate from the configuration that minimizes its transaction costs. Forcing firms to externalize their marketing functions requires the creation of mechanisms to allow those invoking wholesale access to obtain the services of the network. Although the fact that the network owner already offers this service to its own custom