Abstract: According to an embodiment, an information processing device is connected to a management apparatus via a network. The device includes a receiver, an acquisition unit, an MKB processor, and an authentication unit. The receiver is configured to receive communication information. The acquisition unit is configured to acquire a media key block from the management apparatus, in response to receipt of the communication information from a first external device not belonging to a group previously classified on a management unit basis by the management apparatus, the first external device and the information processing device being enabled to derive a first group key based on the media key block. The MKB processor is configured to generate the group key from a device key of the information processing device and the media key block. The authentication unit is configured to perform encrypted communication with the external device based on an authentication method using the group key.

Abstract: According to an embodiment, an information processing device includes: an extracting unit configured to extract a feature quantity of a content; a first detecting unit configured to detect a point in the content where variation of the feature quantity is a first predetermined amount or more; a second detecting unit configured to detect components of watermark information including components corresponding to respective intervals based on the point; a determining unit configured to determine a reliability of the watermark information that is detected; and a selecting unit configured to select a first watermark information from the watermark information based on a result of determination determined by the determining unit.

Abstract: An apparatus includes a first processing unit to judge, whether the route information storing unit stores a second next destination address; a second processing unit to judge whether a received packet includes an message authentication code, in the case where the route-information storing unit stores the second next destination address; a third processing unit to judge whether the key-information storing unit stores a second shared key, which is a first shared key shared between the information processing apparatus, in the case where the received packet does not include the message authentication code for the second next destination address; a third packet generating unit to generate a third packet, which includes a next destination and information indicating that the generation of an message authentication code is impossible, in the case where the key information storing unit does not store the second shared key.

Abstract: According to an aspect of the present invention, there is provided a data transmitting apparatus including an authenticator generating unit and a communicating unit. The authenticator generating unit generates a first authenticator by using a first encryption key and generates a second authenticator including a first to an n-th fragment information items by using a second encryption key. The communicating unit transmits a first packet including the first authenticator and the first fragment information item to a destination device and, after the first packet is transmitted, if a response indicating successful authentication is not received from the destination device within a certain period, sequentially transmits an i-th packet (i is an integer being 2 or more and n or less) including the i-th fragment information item to the destination device.

Abstract: According to an embodiment, a communication device includes a version storage unit, a receiving unit, a determining unit, and a command processing unit. The version storage unit is configured to store therein the first version information. The receiving unit is configured to receive a command including the second version information. The determining unit is configured to determine whether a version represented by the second version information is a next version after a version represented by the first version information. The command processing unit is configured to, based on a determination result of the determining unit and decision information that defines processes corresponding to a command and the determination result, execute processes corresponding to a received command.

Abstract: According to one embodiment, an authenticator which authenticates an authenticatee, which stores first key information (NKey) that is hidden, includes a memory configured to store second key information (HKey) which is hidden, a random number generation module configured to generate random number information, and a data generation module configured to generate a session key (SKey) by using the second key information (HKey) and the random number information. The authenticator is configured such that the second key information (HKey) is generated from the first key information (NKey) but the first key information (NKey) is not generated from the second key information (HKey).

Abstract: According to one embodiment, an authenticator which authenticates an authenticatee, which stores first key information (NKey) that is hidden, includes a memory configured to store second key information (HKey) which is hidden, a random number generation module configured to generate random number information, and a data generation module configured to generate a session key (SKey) by using the second key information (HKey) and the random number information. The authenticator is configured such that the second key information (HKey) is generated from the first key information (NKey) but the first key information (NKey) is not generated from the second key information (HKey).

Abstract: According to one embodiment, an authenticator which authenticates an authenticatee, which stores first key information (NKey) that is hidden, includes a memory configured to store second key information (HKey) which is hidden, a random number generation module configured to generate random number information, and a data generation module configured to generate a session key (SKey) by using the second key information (HKey) and the random number information. The authenticator is configured such that the second key information (HKey) is generated from the first key information (NKey) but the first key information (NKey) is not generated from the second key information (HKey).

Abstract: An apparatus includes a first processing unit to judge, whether the route information storing unit stores a second next destination address; a second processing unit to judge whether a received packet includes an message authentication code, in the case where the route-information storing unit stores the second next destination address; a third processing unit to judge whether the key-information storing unit stores a second shared key, which is a first shared key shared between the information processing apparatus, in the case where the received packet does not include the message authentication code for the second next destination address; a third packet generating unit to generate a third packet, which includes a next destination and information indicating that the generation of an message authentication code is impossible, in the case where the key information storing unit does not store the second shared key.

Abstract: According to an aspect of the present invention, there is provided a data transmitting apparatus including an authenticator generating unit and a communicating unit. The authenticator generating unit generates a first authenticator by using a first encryption key and generates a second authenticator including a first to an n-th fragment information items by using a second encryption key. The communicating unit transmits a first packet including the first authenticator and the first fragment information item to a destination device and, after the first packet is transmitted, if a response indicating successful authentication is not received from the destination device within a certain period, sequentially transmits an i-th packet (i is an integer being 2 or more and n or less) including the i-th fragment information item to the destination device.

Abstract: According to an embodiment, an information processing device includes: an extracting unit configured to extract a feature quantity of a content; a first detecting unit configured to detect a point in the content where variation of the feature quantity is a first predetermined amount or more; a second detecting unit configured to detect components of watermark information including components corresponding to respective intervals based on the point; a determining unit configured to determine a reliability of the watermark information that is detected; and a selecting unit configured to select a first watermark information from the watermark information based on a result of determination determined by the determining unit.