Research And Simulation Implementation Of NGN TISPAN RACS

NGN is based on IMS network technology to build the network structure.ETSI TISPAN NGN can support open architecture with multi-service,fixed-mobile convergence,control and bearer separation,managed broadband network,access interface.Besides it also supports PSTN/ISDN simulation service,IMS,streaming media and other services.TISPAN defines the Resource Admission Control Sub-system (RACS), to be responsible for policy control, resource reservation, and admission control for bearer network.At the same time,it is of Network Address Translation(NAT) and Firewall Traversal.RACS R1,R2 have been released.Now the R3 is being defined.RACS R1 mainly considered the fixed access network QoS control mechanism.RACS R2 mainly added the function of multicast resource control. It is still lack of good consideration for research and implementation of TISPAN RACS at present. So it has great meaning for research and implementation of TISPAN RACS in this paper.This paper is based on IMS to research the RACS and implement on the open source software platform. At first, this thesis explains background, functional parts and protocol of IMS. Then it focus on TISPAN RACS architecture, including function entities,interfaces and interactive process. The open source software, OSIMS and UCT PCF, is analyzed for the implementation of RACS. Then this paper focus on the design and implementation, including RACS overall architecture and resource request flow, access and aggregation segment network topology, M algorithm for achieving admission control. The design of RACS is investigated and verified in the sixth chapter. At last, the paper is reviewed and points out some issues that can be further researched in the future.