应用层组播时延模型及出度优化算法

为了使应用层组播(ALM)的数据包转发时延能够满足组播应用的要求,根据ALM时延特性建立了ALM时延模型,提出并证明了ALM具有最小平均时延和最小最大时延的ALM最小时延定理,同时根据该定理设计了ALM节点主动调节出度的时延优化算法(AOLA)和被动调节出度的时延优化算法(POLA),两个算法在全局优化策略和局部优化策略下的复杂度分别为O(N)和O(logN).仿真实验表明:所提出的ALM时延模型和ALM最小时延定理是正确的,AOLA和POLA时延优化算法能够显著减小ALM时延,其优化效率最高可达58.76%.

Research on the model and algorithms based on out-degree optimization for application multicast layer

To satisfy latency requirements of multicast applications,a latency model of application layer multicast(ALM) is established according to its characteristics.The minimum latency theorem of ALM is proposed and proved.The active optimizing latency algorithm(AOLA) and the passive optimizing latency algorithm(POLA) based on modulating the average out-degrees of ALM groups,are designed with the complexities,O(N) and O(logN),under the conditions on global and partial optimization respectively according to the theorem mentioned above.The simulations results show that the latency model and the minimum latency theorem of ALM are correct,both AOLA and POLA can obviously reduce the ALM latency,and the maximum optimization efficiency reaches to 58.76?%.