Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Regular expression matching equipment and method on basis of deterministic finite automaton

A technology of expression matching and finite state, which is applied in the fields of instrumentation, computing, and electrical digital data processing, etc., can solve the problems of DFA space explosion and difficulty in supporting regular expressions, and achieve the effect of fast matching speed and reduced storage space

Active Publication Date: 2015-04-01
DAWNING INFORMATION IND BEIJING +1
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Various state machines are mainly used to achieve regular expression matching, but DFA has the problem of space explosion, and it is difficult to support more regular expressions

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Regular expression matching equipment and method on basis of deterministic finite automaton
  • Regular expression matching equipment and method on basis of deterministic finite automaton
  • Regular expression matching equipment and method on basis of deterministic finite automaton

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0028] The key steps are illustrated through an example of a regular expression and its DFA. Suppose the regular expression is: \$[0-9]+(\.[0-9][0-9])? .

[0029] The role of this expression is to identify the number of dollars (beginning with $, followed by multiple numbers, if there is a ".", it must be followed by two numbers, such as "$12" and "$12.34" can be successfully matched). figure 1 is a state transition diagram, figure 2 is the state transition table. The transfer table has 256 columns (the character set of this paper is example with the ASCII character table, so there are 256 next states, but the applicable character set of the present invention is not limited to the ASCII table), corresponding to 256 values ​​of a byte respectively; The ~... in the last column in the figure represents all letters except 0~9, ., $. The jump process is as follows. Assuming you are in state C, if you enter "$", you will enter state B; if you enter a value between 0 and 9, you...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention provides regular expression matching equipment and a method on the basis of a deterministic finite automaton. The regular expression matching equipment comprises a packet dispatcher and a result collecting module. A regular expression matching system comprises a matching unit and a storage unit connected with the matching unit, the matching unit is respectively connected with the packet dispatcher and the result collecting module. In the method, each status transfer table is disintegrated into a character substitution table and a simplified status table, many statuses have identical character substitution tables and can be shared after disintegration, and furthermore, many statuses have identical character substitution tables, and can share the identical character substitution tables after minority skips are extracted. By the regular expression matching equipment and the method on the basis of the deterministic finite automaton, storage space for the DFA (deterministic finite automaton) is greatly reduced, and more regular expressions can be stored in a limited space.

Description

technical field [0001] The invention relates to the field of regular expressions belonging to network information processing, in particular to a regular expression matching device and method based on a definite finite state automaton. Background technique [0002] Regular expressions are widely used in the field of network information processing, such as protocol identification, intrusion detection, etc. Various state machines are mainly used to achieve regular expression matching, but DFA has the problem of space explosion, and it is difficult to support more regular expressions. There are several regular expression matching schemes using DFA at present. One is to appropriately rewrite regular expressions to improve storage efficiency; the second is to mine the characteristics of state transitions. For example, the next state of most states has only a few different values. Delayed transfer and other methods can be used to reduce the cost of matching speed. Save storage sp...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): G06F17/30
Inventor 刘兴奎张英文李静李锋伟窦晓光
Owner DAWNING INFORMATION IND BEIJING
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com