Research And Implementation On User Equipment Of Light-Weighted Voip System

With the rapid development of Internet technology, the solutions for traditional VoIP applications have been very mature on both signaling and media part, but still can not get rid of the performance bottleneck and other problems caused by the centralized deployment server. The P2P technology has the capacities like strong self-organization, self-disaster recovery and dynamic load balancing which can solve the problems caused by the centralized deployment server. In order to have a better integration for VoIP and P2P technology, IETF P2P-SIP working group proposed the RELOAD protocol for resources location and discovery in P2P overlay. Compared with the traditional telecommunication VoIP system, the RELOAD protocol based light-weighted VoIP system is much stronger in self-organization and local dynamic load balancing capabilities, and have higher requirements on its user quipments. For this demand, this paper researches and implements one RELOAD protocol based light-weighted VoIP system user equipment. Compared with the traditional VoIP terminal, the light-weighted VoIP system user equipment not only supports all the basic functions like users management, instant message, friends management and audio/video multimedia session, but also supports the capacities of NAT traversal, core network dynamic perception and upgraded to the super nodes of P2P overlay.In order to enable the user equipment access the light-weighted VoIP system normally, this paper researches the IETF RELOAD protocol to ensure the terminals have the function of resources location and discovery, includes the NAT traversal accomoplished by IETF ICE.Because the light-weighted VoIP system user quipment has the requirements of dynamic core network awareness and upgrading to the core network nodes,this paper focuses on the design and implementation of terminals upgrading strategies and basic flows, summed up the basic functional requirements and business processes of user equipments.Finally implements one user equipment for the RELOAD protocol based light-weighted VoIP system with the function of NAT traversal and client upgrading to super node,and the functional tests have been done in the laboratory.The implementation of light-weighted VoIP system user equipment based on the open source SIP terminal called Jitsi,using Java OSGi as its service framework, completing the RELOAD protocol stack access by using JNI technology, making the service and implementation separated completely, reducing the coupling between the functional modules to ensure the stability and scalability of the user terminal and system.The user equipment of light-weighted VoIP system represents the development direction for the terminal of future P2P technology based VoIP system.