Patent ID: 8015614
Filing Date: 2011-09-06
Classification: G06F

Abstract:
1. An information security device which receives content information from a source device, uses the content information, and sends the content information to a destination device, said information security device comprising: a receiving unit which receives, from the source device, the content information and a usage rule of the content information; a content information storage unit which stores the content information and the usage rule; a sending unit which sends, to the destination device, the content information and the usage rule: a chain information generation unit which generates, as chain information of the content information, information including at least an identifier of the destination device to which the content information is sent; a determination unit which determines whether or not the usage rule of the content information is permitted to be changed; a rule change command generation unit which generates a rule change command for instructing to change the usage rule of the content information, the rule change command being issued for the destination device having the identifier indicated in the chain information, when said determination unit determines that the usage rule of the content information is permitted to be changed; and a control unit which changes the usage rule based on the rule change command, wherein said control unit deletes the content information stored in said content information storage unit, when said determination unit determines that the usage rule of the content information is permitted to be changed, and said sending unit sends the rule change command generated by said rule change command generation unit, to the destination device having the identifier indicated in the chain information.