The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 11, 2007
Filed:
Jan. 10, 2003
Rina Panigrahy, Sunnyvale, CA (US);
William Nelson, Los Altos, CA (US);
Anh Tien Nguyen, Cupertino, CA (US);
Rina Panigrahy, Sunnyvale, CA (US);
William Nelson, Los Altos, CA (US);
Anh Tien Nguyen, Cupertino, CA (US);
Cisco Technology, Inc., San Jose, CA (US);
Abstract
Methods and apparatus are disclosed for regular expression matching, especially for, but not limited to high-speed applications such as in a packet switching system (e.g., a router). One implementation includes a matching mechanism for processing each character of a plurality of input characters to progressively generate keyword indications of matched keywords as matched keywords are identified, and for generating one or more matching indications of matched base expressions and non-keyword expressions. These indications are received by a matched regular expression detection mechanism which generates one or more matched regular expression indications based on said one or more keyword indications and said one or more matching indications. In one implementation, the matched regular expression detection mechanism maintains a keyword data structure, which is updated as matched keyword indications are received to ensure they are matched in a proper order. One implementation uses a bitmap to track the matched keywords and AND-SHIFT-OR operations to efficiently update the bitmap.