Patent ID: 8402272

Claim:
A master unit which manages registration of a slave unit, the master unit comprising: a first communication section which receives an input of identification information of the slave unit; a secret address generation and setup section including a processor which: selects a secret address generator having a value that varies every time the secret address generator is generated; and generates, based on the selected secret address generator and the identification information of the slave unit, a secret address of the slave unit to be used temporarily instead of a unique address of the slave unit; a second communication section which: transmits to and receives from the slave unit a notice relating to a registration process; transmits, to the slave unit, a registration start notice storing the secret address generator, the registration start notice being transmitted by a broadcast; and describes, when transmitting the notice relating to the registration process to the slave unit, the secret address of the slave unit and a unique address of the master unit as a destination address for the slave unit and a source address, respectively; a registration information storing section which stores registration information of the slave unit; a registration process section including a processor which: generates a registration authentication key to be used as an encryption key for encrypting communication with the slave unit; generates a unique key of the slave unit by transmitting to and receiving from the slave unit, unique key generation information encrypted using the generated registration authentication key; receives from the slave unit the unique address of the slave unit encrypted using one of the registration authentication key and the unique key of the slave unit; and stores the identification information of the slave unit, the unique address of the slave unit, and the unique key of the slave unit in association with one another in the registration information storing section.