A framework of software-based PBX services over Internet

Although Internet is a powerful and economical communication vehicle, its poor quality-of-service (QoS) is still the major obstacle for multimedia transport over Internet. Basically, both the high-speed broadband network platform and the effective multimedia application platform are needed to gain and promote the benefit of multimedia services to end-users. The ATM-based broadband network would be an adequate inter-network platform for multimedia communication. In general, different application platforms will be needed for different traffic requirements. In multimedia applications, a hybrid service is essential for supporting real-time traffic and non-real-time traffic simultaneously, for example in a conference call, data and voice have to be transferred at the same time. The goal of this paper is to design a framework which can support PBX services with multicasting capability for TCP/IP running over Internet and provide portability to the upper-layer distributed applications. A model of the hierarchical service architecture is proposed to solve the problem of QoS for end-users. Finally, we build an agent-oriented framework for distributed switching agent with object caching mechanism to provide the capability of having a better deployment to clients