Content protection system

• US 20030041262A1
• Filed: 08/22/2002
• Published: 02/27/2003
• Est. Priority Date: 08/23/2001
• Status: Abandoned Application

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Kon, Masashi
• Application Number:
  US10/226,516
• Publication Number:
  US 20030041262A1
• Time in Patent Office: Days
• US Class Current: 713/200
• CPC Class Codes: H04L 63/06 for supporting key management in a packet data network cryptographic mechanisms or cryptographic arrangements for key management H04L9/08
• CPC Class Codes: H04L 63/0823 using certificates cryptographic mechanisms or cryptographic arrangements for entity authentication involving certificates H04L9/3263

Abstract

A content distributing server refers to user authenticating open key certificates transmitted from user equipment to authenticate users. Further, it inserts an electronic watermark into a content in which any electronic watermark has not yet been inserted. A check server checks contents stocked in the content distributing servers, and if unjustness is detected, it requests an authentication organization server to rescind the user authenticating open key certificate of the content distributing server. The authentication organization server issues the open key certificates for authentication of users and content distributing servers and a rescission list in which only rescinded open key certificates are described. Further, the rescission list is renewed on the basis of a notification from the check server.

Claims

1. A content protection system for content distributing servers for accumulating contents to be transmitted in response to requests for use, comprising:

at least one content distributing server including a user equipment authenticator for referring to an open key certificate of user equipment making a request for use to authenticate the user equipment, an electronic watermark processor for inserting electronic watermarks into the contents, and a transmitter for transmitting the contents;

a check server including a first content distributing server authenticator for authenticating the content distributing server based on an open key certificate for authenticating the content distributing server, and determination unit for checking the contents held in said content distributing server;

an authentication organization server including an issuing unit for issuing the open key certificate for authenticating the user equipment and the open key certificate for authenticating the content distributing server, and a rescission list indicating rescinded open key certificates, and a renewing unit for renewing the rescission list on the basis of a notification from the check server; and

at least one user equipment including a second content distributing server authenticator for referring to an open key certificate for authenticating the content distributing server to authenticate the content distributing server, and an executor for executing content received from the content distributing server.

2. A content protection system as claimed in claim 1, wherein the open key certificate is an open key certificate for authentication that is commonly used by content distributing servers.

3. A content protection system as claimed in claim 1, wherein the executor equipped to the user equipment removes an electronic watermark from the content.

4. A content protection system, comprising:

a check server including a first content distributing server authenticator for authenticating a content distributing server based on an open key certificate for authenticating the content distributing server which transmits content to be distributed in response to a request from user equipment, and determination unit for checking contents held in the content distributing server; and

an authentication organization server including a rescission list issuing unit for issuing a rescission list that specifies rescinded open key certificates out of the open key certificates for authenticating the user equipment and the content distributing server, and a renewing unit for renewing a rescission list in response to an addition request

of rescinded open key certificates into the rescission list from the check server, wherein the authentication of the content distributing server is carried out by referring to the open key certificate for authenticating the content distributing server, and the user equipment is allowed to reproduce the content.

5. A content protection method for content distributing servers for accumulating contents to be transmitted in response to requests for use, the method comprising the steps of:

referring to an open key certificate of user equipment making a request for use to authenticate the user equipment;

inserting electronic watermarks into the contents;

transmitting the contents;

authenticating the content distributing server based on an open key certificate for authenticating the content distributing server;

checking the contents held in the content distributing server;

issuing the open key certificate for authenticating the user equipment and the open key certificate for authenticating the content distributing server, and a rescission list indicating rescinded open key certificates;

renewing the rescission list;

referring to an open key certificate for authenticating the content distributing server to authenticate the content distributing server; and

executing content received from the content distributing server in the user equipment.

6. A content protection method, the method comprising the steps of:

authenticating a content distributing server based on an open key certificate for authenticating the content distributing server which transmits a content to be distributed in response to a request for use;

checking contents held in the content distributing server;

issuing a rescission list that specifies rescinded open key certificates out of the open key certificates for authenticating the user equipment and the content distributing server; and

renewing a rescission list in response to an addition request of rescinded open key certificates into the rescission list from a check server, wherein the authentication of the content distributing server is carried out by referring to the open key certificate for authenticating the content distributing server, and the user equipment is allowed to reproduce the content.