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I HISTORY OF 9-1-1 The concept of a three -digit uniform emergency telephone number has existed for decades in the United States and for even longer in Great Britain and other European countries. In 1957, the National Association of Fire Chiefs recommended the use of a single number for reporting fires. While no action was taken at the time, the concern of the firefighting community set the groundwork for future governmental action. In 1967, a Presidential Advisory Commission recommended establishment of a common nationwide telephone number for public use in an emergency. In November 1967, the FCC met with the American Telephone and Telegraph Company (AT&T) to find a means of establishing a universal emergency number that could be implemented quickly. In 1968 the digits 9-1-1 were reserved for this purpose. Later that same year, the first 9-1- 1 call was placed from the Haleyville City Hall in Alabama to the city's police station. In the early 1970's technological advances in communications led to the establishment of Enhanced 9-1-1 (E911) services that originally included 9-1-1 selective routing, automatic location information (ALI) and automatic number identification (ANI). By the end of 1976, 9-1-1 was serving about 17 percent of the population of the United States. In 1979, approximately 26 percent of the population of the United States had 9-1-1 service, and nine states had enacted 9-1-1 legislation. At this time, 9-1-1 service was growing at the rate of 70 new systems per year. By 1987, those figures had grown to indicate that 50 percent of the US population had access to 9-1-1 emergency service numbers. E911 eventually evolved to include selective transfer, fixed transfer, alternate routing, default routing, PSAP evacuation (abandonment) routing and call detail record. The ability to automatically identify the location of the telephone from which the call originated made 9-1-1 an even more attractive system for urban, multi jurisdictional areas. At the end of the 20th century, nearly 93 percent of the population of the United States was covered by some type of 9-1-1 service. Ninety-five percent of that coverage was Enhanced 9-1-1 (E9- 1-1). Currently, 96 percent of the geographic US is currently covered by some type of 9- 1-1. Location -based functionality remains at the center of our legacy 9-1-1 system today. When a 9-1-1 call is made, it arrives at the appropriate PSAP after it is routed across the Public Switched Telephone Network (PSTN) to a special, often dedicated, telephony switching platform called a selective router. To determine routing, the tandem office 9-1- 1 selective router queries the selective routing database (SRDB) using the ANI to match the location of the caller to the emergency service number (ESN), which defines the appropriate PSAP. The ESN is predetermined for each possible originating telephone number using master street address guide (MSAG). When the voice call with its associated ANI is delivered to the PSAP, another query is made from the PSAP's equipment to the ALI database, again using the ANI as a search key. The associated ALI record is then returned to the PSAP where the customer premise equipment (CPE) displays the location on the call taker computer display. When wireless telephone service emerged and began to sweep the country in the early 1990s, the legacy 9-1-1 network faced another challenge. At that time, wireless phones were not usually used for wireline replacement but rather for mobile calling typically outside of a building. In the E9-1-1 system, location information was based on the fixed 13