ABSTRACT
THE PAST FEW YEARS HAVE BEEN MARKED by unprecedented technological innovation in the communications field. Not only have new offerings such as frame relay and SMDS demonstrated their value, but older services such as X.25, T1/T3, and Integrated Services Digital Network are being revitalized. Making their debut are several new technologies that leverage the carrier’s existing local loop infrastructure in support of high-speed data, including asymmetric digital subscriber line (ADSL) and high-bit-rate digital subscriber line (HDSL). Also being deployed are new wireless technologies, including Cellular Digital Packet Data, that connect mobile computer users to each other as well as to the data center. In addition, the country’s entire communications infrastructure is poised for advancement with Synchronous Optical NETwork and Asynchronous Transfer Mode technologies for transmission and switching at multigigabit speeds. Long term, the combination of SONET and ATM paves the way for broadband ISDN (BISDN).
