Decoding a partially encrypted data stream may include receiving and scanning the partially encrypted data stream. Scanning the partially encrypted data stream may include identifying an encrypted portion sentinel in the partially encrypted data stream subsequent to a first portion, identifying an encrypted portion in the partially encrypted data stream subsequent to the encrypted portion sentinel, and generating a decrypted data portion by decrypting the encrypted portion. Decrypting the encrypted portion may include identifying an encrypted data portion in the encrypted portion, the encrypted data portion omitting an end encrypted portion sentinel, decrypting the encrypted data portion, and identifying an end encrypted portion sentinel in the encrypted portion subsequent to the encrypted data portion. Decoding the partially encrypted data stream may include including the decrypted data portion in the decrypted output data stream, and outputting the decrypted output data stream to a client device in the second network domain.

Decoding a partially encrypted data stream may include receiving and scanning the partially encrypted data stream. Scanning the partially encrypted data stream may include identifying an encrypted portion sentinel in the partially encrypted data stream subsequent to a first portion, identifying an encrypted portion in the partially encrypted data stream subsequent to the encrypted portion sentinel, and generating a decrypted data portion by decrypting the encrypted portion. Decrypting the encrypted portion may include identifying an encrypted data portion in the encrypted portion, the encrypted data portion omitting an end encrypted portion sentinel, decrypting the encrypted data portion, and identifying an end encrypted portion sentinel in the encrypted portion subsequent to the encrypted data portion. Decoding the partially encrypted data stream may include including the decrypted data portion in the decrypted output data stream, and outputting the decrypted output data stream to a client device in the second network domain.

An extraction device includes: at least one memory configured to store instructions; and at least one processor configured to execute the instructions to: sort each set of frames that have the same identifier associated with a node, into frames maintaining a cycle and frames out of the cycle; and extract, as an event rule, a feature of a bit change in a data field related to an event occurrence, from the frames that have the same identifier and are out of the cycle.

An extraction device includes: at least one memory configured to store instructions; and at least one processor configured to execute the instructions to: sort each set of frames that have the same identifier associated with a node, into frames maintaining a cycle and frames out of the cycle; and extract, as an event rule, a feature of a bit change in a data field related to an event occurrence, from the frames that have the same identifier and are out of the cycle.

Decoding a partially encrypted data stream may include receiving and scanning the partially encrypted data stream. Scanning the partially encrypted data stream may include identifying an encrypted portion sentinel in the partially encrypted data stream subsequent to a first portion, identifying an encrypted portion in the partially encrypted data stream subsequent to the encrypted portion sentinel, and generating a decrypted data portion by decrypting the encrypted portion. Decrypting the encrypted portion may include identifying an encrypted data portion in the encrypted portion, the encrypted data portion omitting an end encrypted portion sentinel, decrypting the encrypted data portion, and identifying an end encrypted portion sentinel in the encrypted portion subsequent to the encrypted data portion. Decoding the partially encrypted data stream may include including the decrypted data portion in the decrypted output data stream, and outputting the decrypted output data stream to a client device in the second network domain.

Decoding a partially encrypted data stream may include receiving and scanning the partially encrypted data stream. Scanning the partially encrypted data stream may include identifying an encrypted portion sentinel in the partially encrypted data stream subsequent to a first portion, identifying an encrypted portion in the partially encrypted data stream subsequent to the encrypted portion sentinel, and generating a decrypted data portion by decrypting the encrypted portion. Decrypting the encrypted portion may include identifying an encrypted data portion in the encrypted portion, the encrypted data portion omitting an end encrypted portion sentinel, decrypting the encrypted data portion, and identifying an end encrypted portion sentinel in the encrypted portion subsequent to the encrypted data portion. Decoding the partially encrypted data stream may include including the decrypted data portion in the decrypted output data stream, and outputting the decrypted output data stream to a client device in the second network domain.

Information processing apparatus, mobile apparatus, and communication systems are disclosed. In one example, an information processing apparatus performs high-speed data transmission of data of a frame including image data, transmits an extended packet including an extended packet header and packet data to a different information processing apparatus. F first protected data of the packet data is generated with use of a session key, and a nonce value for the session key is updated every time the first protected data is generated. Further, the image data is stored in the packet data, the high-speed data transmission includes transmission of part or a whole of the nonce value, and the part or the whole of the nonce value is stored outside the extended packet header and transmitted. As an example, the information processing can be applied to communication systems compliant with the MIPI standard.

A communication device according to the present invention aims to restart data transmission/reception between communication devices in a short amount of time, without performing key sharing again, even when a communication device of a transmitting side is rebooted. The communication device includes a volatile memory storing a count value, a generator generating data including a count value, a communicator transmitting data to another communication device, a storage instructor, each time the communicator transmits data, updating the volatile memory with a count value, and a nonvolatile memory. A count value is incremented each time the communicator transmits data, the storage instructor causes the nonvolatile memory to store a count value at certain intervals, and the generator, when the communication device is rebooted, includes in data a sum of a certain value and a count value stored in the nonvolatile memory.

A communication device according to the present invention aims to restart data transmission/reception between communication devices in a short amount of time, without performing key sharing again, even when a communication device of a transmitting side is rebooted. The communication device includes a volatile memory storing a count value, a generator generating data including a count value, a communicator transmitting data to another communication device, a storage instructor, each time the communicator transmits data, updating the volatile memory with a count value, and a nonvolatile memory. A count value is incremented each time the communicator transmits data, the storage instructor causes the nonvolatile memory to store a count value at certain intervals, and the generator, when the communication device is rebooted, includes in data a sum of a certain value and a count value stored in the nonvolatile memory.

To make high-level copyright protection of transmission audio data possible. Audio data is sequentially transmitted to a reception side via a predetermined transmission channel for each unit audio data. Audio data to be transmitted is encrypted, and encryption information indicating that the audio data has been encrypted is added to the audio data. For example, the encryption information is added using a predetermined bit area of a channel status of each block that is configured every predetermined number of unit audio data pieces.