Research On The Key Technology Of P-NNI Protocol

ATM is the key technology of broadband network, the P-NM protocol is the standard of ATM Forum on NNI. Therefore, the study of P-N7NI protocol has practical value and theory value. This paper presents the general function framework of P-NNI protocol, which may be the basis of further designing P-NNI product. Besides, studies of some key problems of ATM network are made, creative achievements are acquired as follows. Based on the Waxman network model, the Efficient-Controllable network model is presented, which is more similar to practical network, more controllable, and can improve the simulation efficiency, providing a good experiment environment for routing algorithm simulation; Study of communication network QoS routing is made, the Improved Multi-label algorithm is presented, which can improve the performance of algorithm according to the velocity parameter presented by the user .We can get the balance between the convergence velocity of the algorithm and the cost freely. A new path filtrating method is also presented which can delete the worst paths on time when routing, so we can route more freely and efficiently. Furthermore, we prove that paths routed using the improved algorithm are loopless, which further prove that the improved Multi-label algorithm has good performance. Many simulations are done on my network model, which prove that the new algorithm improve the performance of routing to a certain extent. The new algorithm solves the difficult problem of minimal cost routing with multiple constraints more flexibly and efficiently. Researches on the bandwidth requirement of different level key nodes and the reliability of network are done. Some typical kinds of calls are taken into account. Analysis and comparison among them are made. Simulations are made as well as mathematical analysis. The results of analysis and simulation show that the higher the level of key node (physical border node), the heavier service load the node should shoulder, so the bandwidth requirement of the key node is higher, the influence on the reliability of network is heavier, which makes important role to avoiding the arisen of bottleneck link and bottleneck node, improve the QoS and the performance of ATM hierarchical network. The algorithm and theory analysis are also applicable to other communication networks. Because the P-NNI protocol is very complex and need further standardized, implementing the P-NNI protocol still has many difficulty to deal with and many practical work to do. For example, the routing with inaccurate information under the hierarchical structure has no uniform standard, which is the hotspot and the difficulty of network technology research, is one of the bottlenecks that constrain the development of communication technology. After given the framework of P-NNI, we implementing the protocol still have many problems to resolve and much work to do.