Authentication protocols for the broadband ISDN billing system

The broadband integrated services digital network (B-ISDN) offers a wide variety of services to its customers. From both provider's and user's perspective, a fair and flexible billing system is indispensable to the operation of B-ISDN. In this paper, we discuss different billing policies, and their corresponding authentication protocols, which can be used by the B-ISDN billing system. Flat rate and usage-based rate are two most frequently used billing policies. Because of the diversity of B-ISDN services, combining these two billing policies, along with priority pricing, is a feasible scheme for designing a B-ISDN billing system. The membership authentication protocol (MAP) and the personal authentication protocol (PAP) are proposed to support the authentication requirements of the flat rate and usage-based rate billing policies, respectively. The MAP applies the cipher block chaining (CBC) encryption in the two-party authentication protocol, while the PAP is a modified version of the station-to-station (STS) authentication protocol. Both protocols are designed in conjunction with a suggested key management method. Cryptanalysis shows that both the MAP and the PAP are very secure. Simulation results indicate that both protocols are efficient for providing mutual authentication. Together, these two protocols provide a good authentication mechanism to the B-ISDN billing system.