Sampled deterministic finite automata for deep packet inspection

摘要

In one embodiment, a method includes sampling text in a received packet at a network device and analyzing the sampled text using a sampled deterministic finite automata (DFA) to identify matches between a set of regular expressions and the text. The sampled DFA is created with the regular expressions sampled at a sampling rate calculated for the regular expressions using operations including selecting a minimum sampling rate from sampling rates computed for each of the regular expressions based on a minimum length of the text that can match the regular expression. An apparatus and logic are also disclosed herein.

主权项

1. A method comprising:
sampling text in a received packet at a network device; and analyzing the sampled text using a sampled deterministic finite automata (DFA) to identify matches between a set of regular expressions and the text, the sampled DFA created with said regular expressions sampled at a sampling rate, the sampling rate calculated for said regular expressions using operations comprising selecting a minimum sampling rate from sampling rates computed for each of said regular expressions based on a minimum length of the text that can match said regular expression; wherein the minimum length comprises a sum of lengths of substrings in said regular expression.