公开(公告)号：US06792423B1

公开(公告)日：2004-09-14

申请号：US09723717

申请日：2000-11-28

申请人： Clark Debs Jeffries ,  Anthony Matteo Gallo ,  Natarajan Vaidhyanathan ,  Colin Beaton Verrilli

发明人： Clark Debs Jeffries ,  Anthony Matteo Gallo ,  Natarajan Vaidhyanathan ,  Colin Beaton Verrilli

IPC分类号： G06T1730

CPC分类号： G06F17/30985 ,  H04L29/12801 ,  H04L61/6004 ,  Y10S707/99936

摘要： A method and system for finding a longest matching prefix for an input keyword from among multiple prefixes. The prefixes are data strings of varying lengths wherein prefixes of length n or greater are probabilistically a longest prefix match. The method of the present invention begins by mapping the prefixes of length greater than or equal to n1, that is, in the interval [n1, L], into a first lookup system. Remaining prefixes of length less than n1 but greater than or equal to n2, that is, in the interval [n2, n1−1], are mapped into a second index utilizing a second hash function, wherein n2 is less than n1. Further lookup systems on prefixes having lengths in the intervals [n3, n2−1], [n4, n3−1], and so on, may also be utilized, as determined by optimization studies and the statistics of routing tables.

摘要翻译： 一种用于从多个前缀中为输入关键字找到最长匹配前缀的方法和系统。 前缀是具有不同长度的数据串，其长度为n或更大的前缀概率地是最长前缀匹配。 本发明的方法首先将长度大于或等于n1的前缀，即间隔[n1，L]映射到第一查找系统中。 长度小于n1但大于或等于n2的剩余前缀，即在间隔[n2，n1-1]中，使用第二散列函数映射到第二索引，其中n2小于n1。 还可以利用在间隔[n3，n2-1]，[n4，n3-1]等中具有长度的前缀上的进一步查找系统，如通过优化研究和路由表的统计确定的。