Patent · US Expired

Method and apparatus for digital content copy protection

US6711553B1 · kind B1 · utility

22Cited by
12References
30Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 6, 2000
Grant dateMar 23, 2004
Priority date
Expiry dateNov 29, 2021

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06Q20/3823
  • WIPO fieldIT methods for management
  • WIPO sectorElectrical engineering

Abstract

A method, apparatus and a computer program product are described for copy protecting encrypted documents in a client-server system using an unsecured communication channel. The client-server system has clients and a server for storing encrypted documents. Encrypted documents e(Ks, M) are received by a client from the server. Communications on a transmission channel between the client and the server are then authenticated. Such communications also include electronic payments initiated by a user using the client. Upon authenticating or payment, an encrypted document can then be decrypted. After decrypting, the unencrypted document is displayed but prevented from storage at any client unless re-encrypted using a host specific key KH associated with the client to thereby provide a re-encrypted document.

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