| 摘要: |
| 现有互联网基于目的IP地址实施报文转发，传输过程没有关注源IP地址，转发策略不够灵活.基于目的IP地址与源IP地址的二维路由，支持网络提供更灵活的转发服务.但是，源IP地址的引入会急剧增加转发表（forward information base，简称FIB)的存储空间，大幅增加硬件成本.提出了一种二维转发表分解存储模型（decomposition storage model of two-dimensional FIB，简称DSTF)，基于目的IP前缀对转发表进行分解存储.它把归属于同一个簇头IP前缀（cluster-head IP prefix，简称CP)的二维转发项集合作为一个子二维块（sub two-dimensional block，简称STB)，并根据STB所属CP的不同，将转发项存储到不同的线卡（line card，简称LC).报文转发时，系统可根据CP与LC间的对应关系，快速定位报文的宿主线卡（LChost)，并在宿主线卡中实施转发处理.实验结果表明，该模型能将二维转发表均衡存储在不同线卡上，有效地减少了二维转发表在路由系统中的存储空间. |
| 关键词: 二维路由 转发表 分解存储 目的前缀 源前缀 |
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| 基金项目:国家自然科学基金（61373161，61502320)；北京市教委科技计划面上项目（KM201410028015)；北京市优秀人才培养资助青年骨干个人项目（2014000020124G133) |
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| Decomposition Storage Model of Two-Dimensional FIB |
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LAN Li-Jing, CHEN Wen-Long, TANG Xiao-Lan
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College of Information Engineering, Capital Normal University, Beijing 100048, China
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| Abstract: |
| The existing network, which implements the packets forwarding based on the destination IP address, ignores the source IP address in the transmission process, hence its forwarding strategy is not flexible. Based on the destination IP address and the source IP address, the two-dimensional routing supports the network to provide a more flexible forwarding service. But the introduction of the source IP address dramatically increases the storage space of the Forward Information Base (FIB), in addition, it significantly increases the cost of the hardware. This paper presents a decomposition and storage model of two-dimensional FIB (DSTF). According to the destination IP prefixes, DSTF divides the two-dimensional FIB into blocks. And the collection of the two-dimensional routing entries (REs) that are included in the same Cluster-head IP Prefix (CP) is treated as a sub two-dimension block (STB). Then, depending on the different CPs that the STBs belong to, every STB is stored in the different line cards (LC). Meanwhile, in the process of the packets forwarding, according to the corresponding relationship between the CPs and the LCs, the forwarding mechanism can quickly locate the host LC (LChost) of this packet, and implement the packets forwarding in the LChost. Experimental results show that DSTF can decompose and store the two-dimensional FIB in different LCs averagely. Furthermore, it is effective to reduce the storage space of the two-dimensional FIB in the routing system. |
| Key words: two-dimensional routing FIB decomposition storage destination prefix source prefix |
