计算机工程与应用 ›› 2008, Vol. 44 ›› Issue (19): 100-103.

• 网络、通信、安全 • 上一篇    下一篇

一种基于分段式存储的组播路由查找方案

张 军,程东年,黄慧群,张 鹏   

  1. 国家数字交换系统工程技术研究中心,郑州 450002
  • 收稿日期:2007-12-25 修回日期:2008-03-18 出版日期:2008-07-01 发布日期:2008-07-01
  • 通讯作者: 张 军

Multicast IP-routing lookup scheme based on sectional storage

ZHANG Jun,CHENG Dong-nian,HUANG Hui-qun,ZHANG Peng   

  1. National Digital Switching System Engineering & Technological Research Center,Zhengzhou 450002,China
  • Received:2007-12-25 Revised:2008-03-18 Online:2008-07-01 Published:2008-07-01
  • Contact: ZHANG Jun

摘要: 在高端路由器基于硬件的路由查找设计方案中,TCAM(Ternary Content Addressable Memory)因其性能优良而被普遍采用。但通常的TCAM路由查找方式因组播报文路由查找的特殊性,会导致更多的TCAM存储空间被占用以及查找功效的降低。又因其无法流水线操作,限制了组播报文路由查找速度,从而使得该方法将不再适用。提出一种基于分段式存储的解决方案,该方案支持流水线操作,能够实现线速查找组播报文,而且节约了存储空间从而提高了功效。该方案在863重大课题“大规模接入汇聚路由器(Access Convergence Router,ACR)”中得以验证。

关键词: 大规模接入汇聚路由器, 组播路由查找, 三态内容可寻址存储器, 流水线, 分段式存储

Abstract: Using Ternary Content Addressable Memory(TCAM) for the hardware method of IP-routing lookup in high-class router has been gaining popularity due to its deterministic high performance.However,traditional TCAM method will become unfeasible for the multicast IP-routing lookup,because,the specialty of multicast IP-routing lookup make more TCAM memory spaces are occupied and power efficiency is reduced.Also be restricted by its unable to implement pipeline operation,the speed of multicast IP-routing lookup is slow down.In this paper,a scheme based on sectional storage is proposed.Pipeline operation is implemented by this scheme can not only support multicast IP-routing lookup at line-rate,but also the power efficiency is well controlled by decreasing the number of TCAM entries triggered in each lookup operation.Finally the authors have verified this scheme in ACR.

Key words: Access Convergence Rate(ACR), multicast IP-routing lookup, Ternary Content Addressable Memory(TCAM), pipeline, sectional storage