rovide complementary services. Platform access that is available to any and all suppliers of complements constitutes open access. Interconnection access refers to recipro- cal connection agreements between networks that provide access to each other's facilities, forming a larger network in the process. Each type of access has a corresponding set of regulations. Retail access is governed by traditional regulation of retail service, including state regulation of retail service in telecommunications, natural gas, and electricity. Such regulations include control over prices, rates of return, and service quality. Retail access is targeted through common carrier regulations that include service requirements. Wholesale and unbundled access in telecommunications regulation are addressed extensively by the Telecommunications Act of 1996 and FCC regulations. Platform access is addressed by open access regulations and antitrust enforcement, includ- ing merger conditions in the cable television industry. Reciprocal access through The Structure and Functions of Networks Wholesale access Retail access (wholesaler B and final (final customer A) customer A) Interconnection access (Reciprocal connection of networks I and II) Platform access (for final customer A and supplier Unbundled access of complements B) (for competitor C) Figure 1.13. The five forms of access to networks. Solid nodes and links indicate facilities of proprietary networks. Dashed lines indicate links combined with market transactions necessary to provide access. interconnection is also addressed by the Telecommunications Act of 1996 and FCC rule making. 1. Retail Access We interpret retail access to networks simply as the supply of a network's services to customers, just as any other type of producer would use its facilities to provide a service. Thus, retail access to postal networks is the provision of mailing services to customers, both to those customers sending mail and to those customers receiving mail. Retail access to electric power networks is the p