Use of SS7 in D-AMPS-based PCS: orthodoxy vs. heterodoxy

D-AMPS, the digital version of the Advanced Mobile Phone System (AMPS), is among the key technologies for providing personal communications services (PCS). The bulk of signaling in D-AMPS-based PCS, as, in most modern telecommunication systems, is based on Signaling System No. 7 (SS7). SS7 is a general-purpose common channel signaling (CCS) system specified by the International Telecommunication Union Telecommunications Standardization Sector (ITU-T) and adapted to North American needs by the American National Standard Institute (ANSI). Besides the orthodox use for signaling, SS7 is used in D-AMPS-based PCS for operation, administration, maintenance, and provisioning (OAM&P) of the D-AMPS-based PCS network and for the short message service (SMS). This article reviews the use of SS7 in D-AMPS-based PCS. It motivates the need for a gradual return to orthodoxy where this use is confined to signaling. It also proposes alternatives to the current heterodox use. The alternatives the authors suggest are all rooted in orthodoxy.