reaching limit that would, if applied literally, have broken local telephone service for most Ameri- cans. An exchange is a geographic area in which calls to and from are charged at a uniform rate. Nowadays the term rate center is more widely used; more precisely, a rate center is the single geographic point within an exchange that is used for measuring mileage. The United States has almost 20,000 exchanges. Sometimes an exchange is served by a single central office building, also known as a wire center. Sometimes there is more than one wire center in an exchange; sometimes Divestiture: Equal Access and Chinese Walls a wire center serves more than one exchange. The boundaries of an exchange are filed in a state tariff. For instance, all of New York City is technically one exchange, but the much smaller city of Boston is split among 12 exchanges. It was not rational to expect calls within Boston to be carried by a long distance provider. So by the time Judge Greene announced his modifications to the set- tlement, a new term had entered the lexicon, the LATA, or local access and transport area. This was to be the scope of the RBOCs' activities. They could carry traffic within the LATA on a monopoly basis but could not carry traffic across the LATA boundary [12]. LATA boundaries were, in general, based on metropolitan areas and state lines, the former sometimes taking precedence. The FCC drew the lines before divestiture, in a process that involved some jockeying between AT&T and the still-gestating RBOCs. Small or sparsely populated states could be a single LATA, whereas larger states were divided into multiple LATAs. So, for instance, Pennsylvania was divided into six LATAs, one of which, metropolitan Philadelphia, included all of adjacent Delaware. Five of the six New England states became single LATAs. But larger New York was divided into seven LATAs, California into 11, and Texas into 17. The LATA boundary was, in effect, a Chinese Wall, a clear boundary with only limited, tightly controlled crossing points. If