基于中间点划分无冲突哈希的高速包处理  

High-speed packet processing by non-collision hash functions based on middle-point partition

作　　者：张墨华[1] 李戈[2] 

机构地区：[1]河南财经政法大学计算机与信息工程学院,郑州450000 [2]华北水利水电学院水利职业学院信息工程系,郑州450000

出　　处：《计算机应用》2012年第4期999-1002,1016,共5页journal of Computer Applications

摘　　要：通过在高速片上存储器上存储所有的攻击特征,实现对数据包的高速检测。针对有限的片上存储器空间,提出一种新的基于中间点划分无冲突哈希函数的trie树结构,将攻击特征串平均分配到trie树每层的多个组中,实现对片上存储器有效的控制。通过在同一个芯片中采用流水并行方式执行查询操作,获得更高的吞吐量。存储中间点的空间复杂度为O(n),哈希表的构建时间随攻击特征数量线性增长。实验结果表明:该方法降低了片上存储空间需求,在片上存储器只需执行一次即可完成特征匹配操作。High-speed packet inspection can be achieved through storing attack signatures on the high-speed on-chip memory.Concerning the limited on-chip memory,this paper proposed a new trie structure with non-collision hash functions based on middle-point partition.The algorithm evenly partitioned attack signatures into multiple groups at each layer in trie tree to achieve the effective control of memory.The trie-tree structure can be implemented on a single chip and perform query operations by pipelining and parallelism,thus achieving higher throughput.The space complex of storing middle-point is O（n） and the construction time of hash table is linearly growing with the number of attack signatures.The experimental results show that the new structure decreases the demand of on-chip memory and can facilitate access to the attack signature on the on-chip memory while allowing to perform the signatures matching operations only once.

关 键 词：高速包处理 无冲突哈希 中间点划分 TRIE树 片上存储 

分 类 号：TP393.06[自动化与计算机技术—计算机应用技术] TP311.12[自动化与计算机技术—计算机科学与技术]