Service architectures over session initiation protocol
Session Initiation Protocol (SIP) has gained wide acceptance in the Voice over IP community since its introduction, due to its resemblance to HTTP and SMTP. It has been mainly used for initiating, modifying, and terminating of sessions between communicating entities. Many communication services are built upon it, and different programming languages have been defined and used to ease implementation of these services. Range of services include traditional telephony, i.e. abbreviated dialing, call forwarding, call logging, call transfer and new services like click-to-dial, presence, messaging, and third party call control. Service technologies and scripting languages exist to provide these vast range of services.Although Call Processing Language (CPL) supports many services, it lacks the mechanisms to provide third party call control services. This work presents third party call control extensions to CPL. Extensions fulfill the requirement to initiate calls, thus extend capabilities of CPL to cover third party call control services like wake-up, click-to-dial, automatic call based presence services. Similarly, JAIN Architecture have capability to be an open service deployment framework over the Integrated Networks, nonetheless it does not have support for CPL. This work has another focus to develop a CPL adapter module to JAIN SIP by providing necessary interfaces. An architecture deploying the JAIN SIP CPL module has mechanisms to afford these vast services by bridging CPL with JAIN. JAIN SIP CPL service frameworks will posses a fine-grained control over SIP messaging components: SIP proxies, and SIP Back-to-Back-User-Agents (B2BUAs).