通过对无线令牌环协议(WTRP)进行改进,提出了一种新的具有Qos保障且无竞争的分布式并行接入协议(DP—BSCP)。采用嵌入Markov链和概率母函数的分析方法,用限定服务规则进行系统建模,在系统模型的基础上得到了系统的平均排队队长以及平均等待时间的解析结果,同时也分析了不同优先级队列间的性能关系。理论分析和仿真结果是一致的,表明该协议的平均排队等待延迟和平均等待队列长度均比WTRP有很大降低;对不同优先级的数据包均有良好的适应性,满足不同优先级的性能需求且稳定性大大增强,更加适用于多业务的综合服务系统。
A new uncontested distributed parallel access protocol, which is called distributed parallel protocol based on buffer status control (DP-BSCP) and can provide QoS guarantees for Ad hoc network, is presented by improving the wireless token ring protocol (WTRP). The mathematical model is established using the imbedded Markov chain theory and the probability generating function method. Based on the model, the mean value of queue length and message waiting delay are explicitly obtained, as well as the relationship of varied PRI queues. The simulation results illuminate that it is in concordance with the established system, the average delay and average queue length in DP-BSCP system are much more lower than in WTRP system so can meet the demand of the performance asked by the varied PRI data packets, and the stability is enhanced highly and more fit for the integrated services system.