高速路由器中一种实现QoS保证的分组转发方案

Packet forwarding scheme to enforce the quality of service in high-speed routers

针对入出随机早期检测(RIO)算法对支持区分服务的带宽分配产生偏移问题,提出了一种在边界路由器采用漏桶标记算法,核心路由器采用改进的In和Out随机提前检测算法IRIO,支持区分服务的分组转发方案。用ns2仿真器对方案的带宽使用效率、分组转发时延进行了仿真实验,实验结果证明了该方案可为业务提供跳到跳(HopbyHop)的QoS保证;同时仿真结果显示,IRIO与原RIO相比能个别地控制Out队列长度,表明它能够保护TCP流特性,防备突发分组丢失。

The use of an RIO (random rarly detection with in and out) queue management policies was analyzed to develop an improved RIO algorithm. A packet forwarding scheme was proposed to support differentiated services when a token bucket tagged algorithm is employed in edge routers and a random early detection with in and out (IRIO) algorithm in core routers. Tests of the broadband efficiency and delay of packet forwarding using the ns2 network simulator shows that this scheme can guarantee the hop by hop QoS of different services. The improved IRIO appears to be more effective than the original RIO in controlling the each individual out queue length and can protect TCP performance against burst packet loss. 