Modeling Prepaid Application Server of VoIP and Messaging Services for UMTS
Sok‐Ian Sou, Yi‐Bing Lin, Quincy Wu, Jeu‐Yih Jeng · IEEE Transactions on Vehicular Technology · 2007
Universal mobile-telecommunication system supports IP multimedia services through the IP multimedia core-network subsystem (IMS). This paper proposes a prepaid application server (PAS) to handle both the prepaid calls and messaging services in the IMS. When both voice and messaging are simultaneously offered, a potential problem is that the delivery of a message during a call may result in force-termination of that call due to credit depletion. To address this issue, we describe a strategy to determine if a prepaid message can be sent out during a call session. We propose an analytic model to investigate the performance of this strategy. This paper provides guidelines to select appropriate input parameters for the PAS.