Patent ID: 8913747

Claim:
A sensor system, comprising: a first wireless sensor operatively connected to a wireless sensor network and configured to: generate a first sensor public key and a first sensor private key; a second wireless sensor configured to: generate a second sensor public key and a second sensor private key; and send a request to join the wireless sensor network, wherein the request comprises an identification of the second wireless sensor; a storage medium storing a list of authorized sensors including the second wireless sensor; a sensor controller operatively connected to the storage medium and the sensor network, and configured to: generate a first pair of keys comprising a first controller public key and a first controller private key; receive the first sensor public key from the first wireless sensor and send the first controller public key to the first wireless sensor; generate a second pair of keys comprising a second controller public key and a second controller private key; receive the second sensor public key from the second wireless sensor and send the second controller public key to the second wireless sensor; receive the request and confirm the second wireless sensor is authorized to join the wireless sensor network by comparing the identification of the second wireless sensor received by the sensor controller with the list of authorized sensors in the storage medium, wherein the list of authorized sensors exists prior to receiving the request; generate, in response to confirming the second wireless sensor is authorized to join, a group key using a hash function inputting at least the first sensor public key and the second sensor public key; generate a first encrypted group key by encrypting the group key using the first controller private key; sending the first encrypted group key to the first wireless sensor; generate a second encrypted group key by encrypting the group key using the second controller private key; and send the second encrypted group key to the second wireless sensor, wherein the first wireless sensor decrypts the first encrypted group key using the first controller public key, wherein the second wireless sensor decrypts the second encrypted group key using the second controller public key; wherein the first wireless sensor and the second wireless sensor transmit data encrypted using the group key, wherein the first wireless sensor is wirelessly coupled to the sensor controller through an intermediate device, wherein the intermediate device is a third wireless sensor.