Patent · US Expired

Method and apparatus for collaborative document control

US5787175A · kind A · utility

443Cited by
23References
70Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 23, 1995
Grant dateJul 28, 1998
Priority date
Expiry dateOct 23, 2015

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S707/99938
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A method and apparatus are disclosed for controlling collaborative access to a work group document by the users of a computer system. A combination of public-key cryptographic methods, symmetric cryptographic methods, and message digest generation methods are used. The document has a data portion and a prefix portion. A computer-implemented collaborative encryption method uses structures in the prefix portion to restrict access to the information stored in the data portion. Users who are currently members of a collaborative group can readily access the information, while users who are not currently members of the group cannot. Other structures in the prefix portion support collaborative signatures, such that members of the group can digitally sign a particular version of the data portion. These collaborative signatures can then be used to identify the signing member and to determine if changes in the data portion were made after the collaborative signature was linked to the document.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.