基于MPLS区分服务的多路径综合方法研究

发布时间：2018-02-01 22:42

本文关键词： 服务质量 MPLS 多路径方法区分服务模型约束路由　出处：《东北大学》2014年硕士论文　论文类型：学位论文

【摘要】：随着Internet的迅猛增长及具有实时要求的新兴业务(如VoIP、视频会议、多媒体远程教学等)不断出现,用户对网络服务质量(Quality of Service, QoS)的要求也越来越高。多路径并行数据传输可以有效聚合使用多条路径的带宽,均衡网络流量,提高网络的可用性和生存性,从而有效提升网络的服务质量。区分服务可以为业务流提供不同的转发处理和执行特定的QoS,所以区分服务和多路径是实现QoS较好的方案。由于目前IP网络中大多数路由算法针对的是同类业务采取尽力而为,为了更好实现QoS,提出了基于MPTCP的粗粒度区分多路径路由算法CDMR。该算法的核心思想是当某条链路同时被两种业务选中时,CDMR算法将此路径分配给实时业务,尽力而为业务重新选择其他路径,目的在于保障实时业务的服务质量；考虑到MPLS与DiffServ具有相似的转发机制,但MPLS DiffServ在解决AF上存在分组顺序的问题,为此提出了一种保障分组顺序不变的多路径路由算法-基于编号的最小代价多路径路由算法NMCM。其核心思想是为每个到来的AF业务请求加上编号,用来表明此分组的顺序,具有惟一性。同时该算法为AF业务每个等级的三个丢弃优先级建立三条不同丢弃率的LSP,以区分业务的优先级；由于EF业务具有低延时和低抖动的最高服务质量的要求,而大多数算法都是寻找一条最佳路径传输,为此提出了基于链路关键度和饱和度的多路径路由算法CSMR,其核心思想是不仅优化路由策略,同时为EF业务传输建立多条LSP。 CSMR分为离线阶段和在线阶段两部分,离线阶段根据网络拓扑信息,确定源/目的节点之间链路的关键度值；在线阶段,根据网络资源利用率确定链路饱和度,然后兼顾链路关键度和链路饱和度得出链路代价函数,利用Dijkstra算法为业务选择代价和最小的路径。经NS2仿真实验表明,CDMR算法中多路径具有明显的优势,并且针对业务类型能够采取相应的选路方式,保证实时业务的QoS；NMCM算法综合考虑跳数、带宽和最小代价和,能够提高网络的吞吐量,减少时延,保证了AF业务的分组顺序；CSMR算法采用多路径传输EF业务,能够提高EF业务的吞吐量,降低业务的平均路径长度,很好保障了EF的QoS。
[Abstract]:With the rapid growth of Internet and the emergence of new business (such as VoIP, video conferencing, multimedia distance learning, etc.) with real-time requirements, etc. The quality of Service (QoS) is becoming more and more important for users. Multipath parallel data transmission can effectively aggregate the bandwidth of multiple paths. Balancing network traffic, improving the availability and survivability of the network, thus effectively improve the quality of service of the network. Differentiated services can provide different forwarding processing and execution of specific QoS for traffic flow. So differentiated service and multipath is a better way to implement QoS. Because most routing algorithms in IP network aim at the same kind of services to take best efforts to achieve better QoS. A coarse-grained differentiated multipath routing algorithm based on MPTCP is proposed. The core idea of the algorithm is when a link is selected by two services at the same time. The CDMR algorithm assigns this path to real-time services and reselects other paths to ensure the QoS of real-time services. Considering that MPLS and DiffServ have similar forwarding mechanism, but MPLS DiffServ has the problem of packet order on AF. In this paper, a new multipath routing algorithm, named NMCM-based minimum cost multipath routing algorithm, is proposed, which guarantees packet sequence invariance. The core idea of NMCM-based routing algorithm is to add numbers to each incoming AF traffic request. The algorithm is used to indicate the order of this packet and is unique. At the same time, the algorithm establishes three LSPs with different dropping rates for three dropping priorities of each level of AF traffic to distinguish the priority of traffic. Because EF traffic has the highest QoS requirement of low delay and low jitter, most algorithms are looking for an optimal path transmission. A multipath routing algorithm CSMRs based on link criticality and saturation is proposed. The core idea of CSMRs is not only to optimize the routing strategy. At the same time, a number of LSP. CSMR for EF traffic transmission are divided into two parts: off-line phase and on-line stage. According to the network topology information, the critical value of the link between the source and destination nodes is determined in the off-line phase. In the online stage, the link saturation is determined according to the network resource utilization ratio, and then the link cost function is obtained by taking into account the link criticality and the link saturation. The Dijkstra algorithm is used to select the cost and the minimum path for the service. The simulation results of NS2 show that the multipath algorithm has obvious advantages. The QoS of real-time service can be guaranteed by adopting the corresponding route selection method according to the service type. The NMCM algorithm can improve the throughput of the network, reduce the delay and ensure the packet order of AF services by considering the sum of hops, bandwidth and minimum cost. The CSMR algorithm uses multipath to transmit EF traffic, which can improve the throughput of EF services, reduce the average path length of service, and ensure the QoS of EF.
【学位授予单位】：东北大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TP393.09

【相似文献】