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:
Sep. 27, 2011
Filed:
Jul. 26, 2006
Mark Henry Butler, Bristol, GB;
Scott Alan Stanley, Pleasanton, CA (US);
Mark Henry Butler, Bristol, GB;
Scott Alan Stanley, Pleasanton, CA (US);
Hewlett-Packard Development Company, L.P., Houston, TX (US);
Abstract
A hierarchical digital signature method is provided by which different levels of data elements of a data entry are processed in turn to derive function values (for example hash function values) for data elements in the level which are to form part of the digital signature. All function values for one level are combined in a further function to provide an additional function value, and the additional function value is used in the processing of data elements in the next level nearer to the root. This provides a digital signature which can use only selected data elements of a data entry, and which is not sensitive to the ordering of the data entry structure.