The Research Of Overload Control Algorithm Based On Parlay

Parlay is an Application Programming Interface (API) which makes IT developer quickly create the telecommunications business. It is mainly designed for using in the mobile network, fixed network and Next Generation Network based on IP. Developers can use a variety of languages such as C, C++ and Java to develop Parlay/OSA applications.As an important Open Application Programming Interface in next-generation network, large numbers of service demands and requisitions are easy to form bottlenecks. So applications based on Parlay needs efficiently overload control. But the features of future business including wide varieties of service, significant difference, high burstiness and different service strategy, cause business overload control is much more complex than traditional Intelligent Network. In order to prevent overload, there must be a corresponding overload control mechanisms. At the same time, in order to ensure good throughput and delay characteristics, a good scheduling algorithm is needed. Therefore, how to provide an effective overload control in the new generation networks has become a focus of current research.At first, this thesis introduces the overload control algorithm studied at home and abroad, as well as overloads control technique mainly used. Second, structure of Parlay and related overload control algorithm is introduced. Then the principle of the overload control on Parlay gateway, the overload control detection algorithm, and the evaluation standards of overload control etc.is briefly introduced.The main research in the thesis as follows:Firstly, Random Early Detection Algorithm is researched. The principle as well as the merit and demerit of RED algorithm are investigated. To overcome the difficulty in configuration parameters, an enhanced RED algorithm with adaptive parameters is proposed. The simulation results show that this enhanced RED algorithm can effectively reflect congestion degree of network. This algorithm has improved the adaptability of the RED algorithm.Secondly, in the light of the priority algorithm and leaky bucket algorithm' advantages and disadvantages, a priority and bucket algorithm-based overload control algorithm is presented in the thesis. On the one hand, the algorithm solves the priority of "starving to death"; On the other hand, it can resolve a waste of resources issues in the bucket algorithm. The simulation shows that this algorithm can effectively solve the Parlay Gateway overload problem, and easily to implement.At the end of the thesis, works have done is summed up, and the development in the future is also prospected.