KEY ALLOCATING METHOD AND KEY ALLOCATION SYSTEM FOR ENCRYPTED COMMUNICATION

• US 20090055649A1
• Filed: 10/21/2008
• Published: 02/26/2009
• Est. Priority Date: 04/08/2004
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: TAKATA, Osamu, Hoshino, Kazuyoshi, Fujishiro, Takahiro, Kaji, Tadashi
• Granted Patent: US 8,238,555 B2
• Time in Patent Office: Days
• US Class Current: 713/171
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• CPC Class Codes: H04L 63/062 for key distribution, e.g. centrally by trusted party cryptographic mechanisms or cryptographic arrangements for key distribution involving a central third party H04L9/0819

Abstract

Both a management server and a validation server are installed. Both a terminal and a terminal register setting information which is usable in an encrypted communication in the management server. When carrying out the encrypted communication, the management server searches the registered setting information for coincident setting information. The management server generates keys for the encrypted communications which can be used by the terminals, and delivers these generated keys in combination with the coincident setting information. The management server authenticates both the terminals in conjunction with the validation server. Since the terminals trust such results that the management server has authenticated the terminals respectively, these terminals need not authenticate the respective communication counter terminals.

Claims

1. A communication system comprising:

a communication source terminal, a communication destination terminal, and a management server;

wherein;

said communication source terminal transmits a connection request between communication source terminal and communication destination terminal to the management server;

said management server searches the setting information for encrypted communications which have been previously registered thereinto by both said communication source terminal and said communication destination terminal for setting information, which of said communication source terminal is coincident with one of said communication destination terminal; and

in the case that the management server can search for the coincident setting information for the encrypted communication, both the communication source terminal and the communication destination terminal perform an encrypted communication by employing a key for the encrypted communication, which has been produced based upon said coincident setting information for the encrypted communication.

2-10. -10. (canceled)