Research on Performance Evaluation of Multimedia Traffic towards Development of Next Generation Internet

1.为了对多媒体业务进行建模，提出并分析了单个服务台偶尔休假的批量到达随机调度排队模型。通信网络的服务质量高度依赖于丢包率，评价其性能通常采用M/G/1/K排队模型。关于分组的调度，到目前为止，在大多数情况下都假设FCFS。我们将该模型扩展到包括随机调度和LCFS调度，并推导出了该情况下的分析结果。提出了CSMA/DRC协议，改进了CSMA协议作为无线移动网络中多媒体业务的随机接入协议，并推导了其性能指标。提出了一种用小波变换来表示互联网上典型的自相似和/或长距离相关流量的数学方法，并验证了该方法的有效性。提出了一种在蜂窝移动网络中有效融合实时业务(如承载语音呼叫的业务)和非实时业务(如来自数据呼叫的业务)的方法，并对其性能进行了评估。提出了一种基于马尔可夫调制泊松过程(MMPP)的自相似流量建模方法，并验证了其有效性。提出并分析了一种在蜂窝网络中同时容纳语音呼叫和数据呼叫并在一定程度上搁置正在进行的数据呼叫的有效融合方案。通过使用FGN过程的仿真，评估了长相关性对MPEG2运动图像业务的影响。

1. A queueing model with batch arrivals and random scheduling of customers where a single server takes vacations occasionally is proposed and analyzed in order to model multimedia traffic.2. QoS of communication networks is highly dependent on the frequency of packet losses, and M/G/1/K queueing model was commonly used to evaluate its performance. Concerning the scheduling of packets, FCFS was assumed so far in most cases. We have extended the model to include random scheduling and LCFS scheduling and derived the analytical results for the case.3. We have proposed CSMA/DRC which improves CSMA as a random access protocol for a variety of traffic from multimedia sources in a wireless mobile networks, and derived its performance measures.4. A mathematical method to represent self-similar and/or long-range-dependent traffic which typically appears in the Internet in terms of Wavelet transform has been developed and its usefulness has been verified.5. A method to efficiently integrate real-time traffic such as that carrying voice calls and non-real-time traffic such as that from data calls in cellular mobile networks has been developed and its performance has been evaluated.6. We have proposed a modeling technique for a class of traffic of self-similarity in terms of MMPP(Markov Modulated Poisson Process) and verified its effectiveness.7. An efficient integration scheme which accommodates both voice calls and data calls in cellular networks and which puts aside on-going data calls to an extent has been proposed and analyzed.8. The effect of long-range dependency on MPEG2 moving image traffic has been evaluated through simulation by using FGN process.