Anchored patterns

Patent metadata

Field	Value
Publication number	US-9514246-B2
Application number	US-201514632448-A
Country	US
Kind code	B2
Filing date	Feb 26, 2015
Priority date	Jun 24, 2011
Publication date	Dec 6, 2016
Grant date	Dec 6, 2016

Abstract

A method and apparatus relate to recognizing anchored patterns from an input stream. Patterns from a plurality of given patterns are marked as anchored patterns. An anchored state tree for the anchored patterns of the plurality of given patterns is built, including nodes representing a state of the anchored state tree. For each node of the anchored state tree, a failure value equivalent to a node representing a state in an unanchored state tree representing unanchored patterns of the plurality of given patterns is determined.

First claim

What is claimed is:

1. A method comprising:
in a processor:
building an unanchored state graph for unanchored patterns of a plurality of given patterns, the unanchored state graph including nodes representing a state of the unanchored state graph;
building a separate anchored state graph for given patterns, of the plurality of given patterns, marked as anchored patterns, the anchored state graph including nodes representing a state of the anchored state graph;
for each node of the anchored state graph, determining a failure value equivalent to a node representing a state in an unanchored state graph representing unanchored patterns of the plurality of given patterns; and
including a failure value of a root node of the anchored state graph, the failure value being equivalent to a root node of the unanchored state graph.

2. The method of claim 1 , wherein the anchored state graph includes a root node that is set as a start node for processing anchored and unanchored patterns in an input payload.

3. The method of claim 1 , further comprising marking the given patterns, of the plurality of given patterns, as the anchored patterns.

4. The method of claim 3 , wherein marking includes adding a reference indicating a location within an input of a string of text to begin searching for the respective anchored pattern.

5. A method comprising:
in a processor:
building an unanchored state graph for unanchored patterns of a plurality of given patterns, the unanchored state graph including nodes representing a state of the unanchored state graph;
building a separate anchored state graph for given patterns, of the plurality of given patterns, marked as anchored patterns, the anchored state graph including nodes representing a state of the anchored state graph;
for each node of the anchored state graph, determining a failure value equivalent to a node representing a state in an unanchored state graph representing unanchored patterns of the plurality of given patterns;
wherein each node of the anchored state graph includes an output function, the output function of each node is calculated as a function of both the anchored patterns and unanchored patterns.

6. The method of claim 5 , further comprising marking the given patterns, of the plurality of given patterns, as the anchored patterns.

7. A method comprising:
in a processor:
building an unanchored state graph for unanchored patterns of a plurality of given patterns, the unanchored state graph including nodes representing a state of the unanchored state graph;
building a separate anchored state graph for given patterns, of the plurality of given patterns, marked as anchored patterns, the anchored state graph including nodes representing a state of the anchored state graph;
for each node of the anchored state graph, determining a failure value equivalent to a node representing a state in an unanchored state graph representing unanchored patterns of the plurality of given patterns;
wherein building the anchored state graph and building the separate unanchored state graph includes determining a number of states and transitions from one state to another.

8. The method of claim 7 , further comprising marking the given patterns, of the plurality of given patterns, as the anchored patterns.

9. A method comprising:
in a processor:
building an unanchored state graph for unanchored patterns of a plurality of given patterns, the unanchored state graph including nodes representing a state of the unanchored state graph;
building a separate anchored state graph for given patterns of the plurality of given patterns, marked as anchored patterns, the anchored state graph including nodes representing a state of the anchored state graph;
for each node of the anchored state graph, determining a failure value equivalent to a node representing a state in an unanchored state graph representing unanchored patterns of the plurality of given patterns;
upon receiving an input string of text, processing the input string of text through the anchored state graph; and
transitioning processing of the input string of text to a node of the unanchored state graph if a character of the input string of text results in one of the determined failure values on one of the nodes of the anchored state graph, the resulting failure value determining the node of the unanchored state graph to transition processing.

10. The method of claim 9 , further comprising marking the given patterns, of the plurality of given patterns, as the anchored patterns.

11. An apparatus comprising a processor configured to implement a compiler, the compiler configured to:
build an unanchored state graph for unanchored patterns of a plurality of given patterns, the unanchored state graph including nodes representing a state of the unanchored state graph;
build a separate anchored state graph for given patterns, of the plurality of given patterns, marked as anchored patterns, the anchored state graph including nodes representing a state of the anchored state graph;
for each node of the anchored state graph, determine a failure value equivalent to a node representing a state in an unanchored state graph representing unanchored patterns of the plurality of given patterns; and
determine a failure value of a root node of the anchored state graph, the failure value being equivalent to a root node of the unanchored state graph.

12. The apparatus of claim 11 , wherein the compiler is further configured to mark the given patterns, of the plurality of given patterns, as the anchored patterns.

13. The apparatus of claim 11 , wherein the anchored state graph includes a root node that is set as a start node for processing anchored and unanchored patterns in an input payload.

14. An apparatus comprising a processor configured to implement a compiler, the compiler configured to:
build an unanchored state graph for unanchored patterns of a plurality of given patterns, the unanchored state graph including nodes representing a state of the unanchored state graph;
build a separate anchored state graph for given patterns, of the plurality of given patterns, marked as anchored patterns, the anchored state graph including nodes representing a state of the anchored state graph;
for each node of the anchored state graph, determine a failure value equivalent to a node representing a state in an unanchored state graph representing unanchored patterns of the plurality of given patterns;
wherein each node of the anchored state graph includes an output function, the output function of each node is calculated as a function of both the anchored patterns and unanchored patterns.

15. The apparatus of claim 14 , wherein the compiler is further configured to mark the given patterns, of the plurality of given patterns, as the anchored patterns.

16. The apparatus of claim 14 , wherein the compiler is further configured to mark the given patterns by adding a reference indicating a location within an input of a string of text to begin searching for the respective anchored pattern.

17. An apparatus comprising a processor configured to implement a compiler, the compiler configured to:
build an unanchored state graph for unanchored patterns of a plurality of given patterns, the unanchored state graph including nodes representing a state of the unanchored state graph;
build a separate anchored state graph for given patterns, of the plurality of given patterns, marked as anchored patterns, the anchored state graph including nodes representing a state of the anchored state graph;
for each node of the anchored state grap

Assignees

• Cavium Inc

Inventors

• Billa Satyanarayana Lakshmipathi
• Goyal Rajan

Classifications

• G06F17/30424

  Physics · mapped topic

• G06F17/30961

  Physics · mapped topic

• G06F17/30958 Primary

  Physics · mapped topic

• G06F17/30327

  Physics · mapped topic

• H04L63/0245

  Filtering by information in the payload · CPC title