Method and device for measuring regular expression state complexity

Abstract

The invention relates to a method and device for measuring regular expression state complexity. The method for the measuring regular expression state complexity comprises the steps that firstly, the curly relationship between any two states p and q in a given non-deterministic type finite automation M is judged, and the curly relationship is one of the five kinds of relationships: the mutual-exclusion relationship, the equivalence relationship, the included relationship, the including relationship and the independent relationship, M = (Q, sigma, delta, q0, F), the Q is a finite set, each element of the Q is called as a state, the sigma is a finite alphabet, each element of the sigma is called as an input character, the delta is a state transition function, and the q0 belongs to the Q, the q0 is the unique starting state, and the F is a terminal state set; two, the regular expression state complexity is estimated according to the judging result of the step one, the state complexity is the state number/Q'/of the deterministic type finite automation M'obtained by determining the M, and the M'=( Q', sigma, delta', q0', F'). The method and device for measuring regular expression state complexity can obtain the reasonable estimating value rapidly, and improve measuring efficiency.

Description

technical field [0001] The invention relates to the field of information technology, in particular to a method and device for measuring the state complexity of a regular expression. Background technique [0002] The complexity and scale of regular expressions in the deep packet inspection system make the classic NFA (Non-deterministic Finite Automaton, non-deterministic finite automaton) and DFA (Deterministic Finite Automaton, deterministic finite automaton) matching methods unable To achieve line speed matching requirements. At present, relevant researchers have proposed a large number of algorithms, architectures and data structures to match the problems of low efficiency and huge memory overhead. However, these works generally have the following problems: 1) Regular expression matching can only be applied on a small scale (dozens or hundreds of lines). Problem; 2) It is only for some special types of regular expressions, and it cannot be solved correctly or even solved...

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Problems solved by technology

[0002] The complexity and scale of regular expressions in the deep packet inspection system make the classic NFA (Non-deterministic Finite Automaton, non-deterministic finite automaton) and DFA (Deterministic Finite Automaton, deterministic finite automaton) matching methods unable Achieving Line Speed ​​Matching Requirements

At present, relevant researchers have proposed a large number of algorithms, architectures and data structures to match the problems of low efficiency and huge memory overhead

However, these works generally have the following problems: 1) Regular expression matching can only be applied on a small scale (dozens or hundreds of lines). Problem; 2) It is only for some special types of regular expressions, and it cannot be solved correctly or even solved for more complex regular expression matching, and it is not universal; 3) Through a large number of tests and comparisons in

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