流分类技术的研究

介绍了流分类算法的概念以及对流分类算法的要求；把目前存在的流分类算法分成三类：多维查找转换为一维查找算法、相关区域查找算法、独立区域查找算法，并对各类算法的性能进行了讨论；通过引入并行流分类算法说明了流分类算法的研究重点是减小存储空间和提高更新速度。
关 键 词 流分类; 多维查找转换为一维查找算法; 相关区域查找算法; 独立区域查找算法; 并行流分类

随着英特网的发展，流分类技术得到广泛地应用，如防火墙、基于策略的路由、流量控制、流量整形、计费等等。与流分类有关的策略和规则的集合称为流分类器或简称分类器。分类器中的每一条规则根据数据包头的某些域来定义数据包所属的流。常用的几个域有：目的IP地址、源IP地址、源端口、目的端口、协议类型等。

Abstract The conception of packet classification and request for it is introduced. The paper classifies the existed packet classification algorithms into three kinds: conversion into single-field search、dependent field search、independent field search, then compare their performance. The presentation of parallel packet classification indicates how to reduce the storage space and update time is the research importance.
Key words packet classification; conversion into single-field search; dependent field search; independent field search; parallel packet classification