| 摘要 |
The present invention relates to communication between a master device and a slave device. An intermediate third party receives a batch of secure commands generated in advance from a master, and plays the commands to be transmitted to a slave in order. The batch includes an initial command displaying establishment of a channel protected by a session key depending on a sequence counter and a second command protected by an MAC code as a session key function. At a time of each new secure channel establishment, sequence counter update in a non-volatile memory of the slave causes the pre-generated batch to be redundant by the new session key. For replay of the batch, the present invention provides respective update values of a counter to be temporarily stored in the non-volatile memory, and provides a current value to be re-entered into a volatile memory in the case of a pre-defined event including a test counter reaching a maximum number of the replays. |
