The paper presents the simulation results of the comparison of three Queuing Mechanisms, First in First out (FIFO), Priority Queuing (PQ), and Weighted Fair Queuing (WFQ). Depending on their effects on the network’s ...The paper presents the simulation results of the comparison of three Queuing Mechanisms, First in First out (FIFO), Priority Queuing (PQ), and Weighted Fair Queuing (WFQ). Depending on their effects on the network’s Routers, the load of any algorithm of them over Router’s CPUs and memory usage, the delay occurred between routers when any algorithm has been used and the network application throughput. This comparison explains that, PQ doesn’t need high specification hardware (memory and CPU) but when used it is not fair, because it serves one application and ignore the other application and FIFO mechanism has smaller queuing delay, otherwise PQ has bigger delay.展开更多
Services provided by internet need guaranteed network performance. Efficient packet queuing and scheduling schemes play key role in achieving this. Internet engineering task force(IETF) has proposed Differentiated Ser...Services provided by internet need guaranteed network performance. Efficient packet queuing and scheduling schemes play key role in achieving this. Internet engineering task force(IETF) has proposed Differentiated Services(Diff Serv) architecture for IP network which is based on classifying packets in to different service classes and scheduling them. Scheduling schemes of today's wireless broadband networks work on service differentiation. In this paper, we present a novel packet queue scheduling algorithm called dynamically weighted low complexity fair queuing(DWLC-FQ) which is an improvement over weighted fair queuing(WFQ) and worstcase fair weighted fair queuing+(WF2Q+). The proposed algorithm incorporates dynamic weight adjustment mechanism to cope with dynamics of data traffic such as burst and overload. It also reduces complexity associated with virtual time update and hence makes it suitable for high speed networks. Simulation results of proposed packet scheduling scheme demonstrate improvement in delay and drop rate performance for constant bit rate and video applications with very little or negligible impact on fairness.展开更多
在现有的无线Mesh网络中,高优先级业务过多地占用信道资源,影响了不同业务之间占用资源的公平性。针对此问题,基于802. 11e EDCA协议,提出一种有限优先权的无线Mesh网络信道分配算法。该算法将信道占用时间比作为调整每个优先级业务优...在现有的无线Mesh网络中,高优先级业务过多地占用信道资源,影响了不同业务之间占用资源的公平性。针对此问题,基于802. 11e EDCA协议,提出一种有限优先权的无线Mesh网络信道分配算法。该算法将信道占用时间比作为调整每个优先级业务优先数的标准,根据网络当前状态和各个优先级业务占用信道资源的情况,通过动态调整低优先级业务的优先权,适当地限制高优先级业务过多地占用信道资源,确保低优先级业务在网络负载较大时也能够占用一定的信道资源。网络仿真实验结果表明,该算法能有效地提高系统吞吐量和资源综合利用率,保证了高、低优先级业务间占用信道资源的公平性。展开更多
文摘The paper presents the simulation results of the comparison of three Queuing Mechanisms, First in First out (FIFO), Priority Queuing (PQ), and Weighted Fair Queuing (WFQ). Depending on their effects on the network’s Routers, the load of any algorithm of them over Router’s CPUs and memory usage, the delay occurred between routers when any algorithm has been used and the network application throughput. This comparison explains that, PQ doesn’t need high specification hardware (memory and CPU) but when used it is not fair, because it serves one application and ignore the other application and FIFO mechanism has smaller queuing delay, otherwise PQ has bigger delay.
文摘Services provided by internet need guaranteed network performance. Efficient packet queuing and scheduling schemes play key role in achieving this. Internet engineering task force(IETF) has proposed Differentiated Services(Diff Serv) architecture for IP network which is based on classifying packets in to different service classes and scheduling them. Scheduling schemes of today's wireless broadband networks work on service differentiation. In this paper, we present a novel packet queue scheduling algorithm called dynamically weighted low complexity fair queuing(DWLC-FQ) which is an improvement over weighted fair queuing(WFQ) and worstcase fair weighted fair queuing+(WF2Q+). The proposed algorithm incorporates dynamic weight adjustment mechanism to cope with dynamics of data traffic such as burst and overload. It also reduces complexity associated with virtual time update and hence makes it suitable for high speed networks. Simulation results of proposed packet scheduling scheme demonstrate improvement in delay and drop rate performance for constant bit rate and video applications with very little or negligible impact on fairness.
基金Supported by the National Natural Science Foundation of China （61071096, 61003233, 61073103 ） and the Research Fund for the Doctoral Program of Higher Education （20100162110012）.
文摘在现有的无线Mesh网络中,高优先级业务过多地占用信道资源,影响了不同业务之间占用资源的公平性。针对此问题,基于802. 11e EDCA协议,提出一种有限优先权的无线Mesh网络信道分配算法。该算法将信道占用时间比作为调整每个优先级业务优先数的标准,根据网络当前状态和各个优先级业务占用信道资源的情况,通过动态调整低优先级业务的优先权,适当地限制高优先级业务过多地占用信道资源,确保低优先级业务在网络负载较大时也能够占用一定的信道资源。网络仿真实验结果表明,该算法能有效地提高系统吞吐量和资源综合利用率,保证了高、低优先级业务间占用信道资源的公平性。
