Service Control Layer (SCL): Enabling Rule-based Control and Enrichment in Next-Generation Telecom Service Delivery

Telecom operators have started to make significant investments towards evolving their Service Delivery Platforms (SDPs) to a next-generation architecture, based on IP technologies and standards such as Session Initiation Protocol (SIP), Service Oriented Architecture (SOA) and increasingly, Web 2.0. These investments are tightly coupled with demands for network middleware infrastructures that allow for rapid service creation and execution, efficient service orchestration and management, and flexible exposure of core network capabilities as services. A key service management functionality of integrated SDP is IP-based service control. Traditionally, service control functionalities have been vertically integrated with service logic and hence, are inflexible and costly to maintain and upgrade. IP Multimedia Subsystem (IMS), which defines the overlay service architecture for next generation networks, stopped short in designing a flexible service control component. In this paper, we present the design and implementation of a service control layer (SCL) for IMS networks, which is flexible on two fronts, viz., the SIP based service modeling for fine grained service control and the programmability of the controlling action implemented by external business services. We present the detailed description of the design and implementation of SCL followed by the results obtained from a performance evaluation exercise that evaluates the scalability of SCL.