高速路由器中一种有效的组播交换排队机制  

An Efficient Queuing and Switching Scheme for Multicast in High-Speed Routers

作　　者：宋美娜[1] 宋俊德[1] 战晓苏[1] 

机构地区：[1]北京邮电大学电子工程学院,北京100876

出　　处：《计算机研究与发展》2005年第5期810-817,共8页Journal of Computer Research and Development

摘　　要：许多Internet新业务产生的网络流量都属于组播类型.高速路由器中组播交换队列设计是解决组播数据在复杂网络中有效传输的关键问题之一.理想情况下,为保证服务的公平性及有效性,不应该在排队和调度时对组播和单播人为地进行区分.在二者共存的情况下,如何进行公平地排队、交换是亟待解决的问题.基于共享存储交换结构,提出了一种有效的组播交换队列设计方案,同时提供了相应的与组播比例和平均扇出相关的缓存管理机制和队列调度算法.仿真结果表明,与在Cisco高端路由器中广泛应用的ESLIP设计方案相比,在输入负载大于80%的重负载环境中,该系统能够获得更低的平均时延和更小的系统丢包率.Many emerging Internet applications are multicast traffic The queuing and switching scheme for multicast in high-speed routers is one of the key elements to enable the multicast traffic traverse the complex network environments Ideally in order to guarantee the fairness between the unicast and multicast traffic we should not differentiate them deliberately when queuing and scheduling Since the increase of multicast traffic will exhaust the resource, the service for unicast traffic will be influenced When the two types of traffic coexist, how to provide the fairness between them from the point of queuing view desiderates to be resolved Based on the shared memory switching architecture, an efficient queuing scheme for multicast packet switching routers is proposed And the corresponding buffer management and scheduling algorithm according to multicast ratio and fanout are also presented based on the proposed queuing scheme On three phases, which are the input buffer, the shared memory and the buffer of egress NP, the bandwidth and buffer allocation for multicast packets is decided according to the multicast traffic ratio and the mean fanout Performance evaluation of the proposed system shows that better average delay and loss performance can be achieved in comparison with the ESLIP system under heavy offered load, which is applied for high-end routers of Cisco

关 键 词：路由器 组播 队列 共享存储 缓存管理 

分 类 号：TN915.05[电子电信—通信与信息系统] TP393[电子电信—信息与通信工程]