Security system for a moveable barrier operator

A method of pairing a first device and a second device to effect secure communication between the first device and the second device, the method comprising:

• transmitting, from the first device, a first encrypted message, the first encrypted message including a first fixed code and a first changing code;
• receiving, by the first device, a response from the second device based on the transmitted first encrypted message;
• decrypting, by the first device, the response;
• based on the decrypting of the response, determining, by the first device, a second fixed code associated with the second device;
• storing, by the first device, the second fixed code in a memory of the first device;
• transmitting, by the first device, a third encrypted message including the first fixed code and a changed version of the first changing code;
• based on the transmitted third encrypted message, receiving, at the first device, a fourth encrypted message from the second device;
• decrypting, by the first device, the fourth encrypted message:
• based on the decrypting of the fourth encrypted message, determining, by the first device, the second fixed code and a second changing code;
• validating, by the first device, the fourth encrypted message by confirming that the second fixed code determined from the response and stored in the memory of the first device matches the second fixed code determined from the fourth encrypted message;
• and
• storing, by the first device, the second changing code in the memory of the first device based on validating the fourth encrypted message.

A method of pairing a first device and a second device to effect secure communication between the first device and the second device, the method comprising:

• receiving, at the second device, while the second device is in a learn mode, a first encrypted message sent from the first device;
• decrypting, by the second device, the first encrypted message;
• based on the decrypting of the first encrypted message, determining by the second device, a first fixed code and a first changing code;
• storing, by the second device, the first fixed code and the first changing code in a memory of the second device;
• based at least on the first fixed code and the first changing code, transmitting, by the second device, a response including a second fixed code;
• based on the transmitted response, receiving, by the second device, a third encrypted message from the first device;
• decrypting, by the second device, the third encrypted message;
• based on the decrypting of the third encrypted message, determining, by the second device, the first fixed code and a changed version of the first changing code;
• validating, by the second device, the third encrypted message by confirming the first fixed code determined from the third encrypted message matches the stored first fixed code and the changed version of the first changing code determined from the third encrypted message matches an expected value of the stored first changing code;
• storing, by the second device, the changed version of the first changing code in the memory of the second device based on validating the third encrypted message;
• and
• in response to validating the third encrypted message, transmitting from the second device a fourth encrypted message including the second fixed code and a second changing code.

A first device configured to be paired to a second device to effect secure communication between the first device and the second device, the first device comprising:

• a controller circuit;
• a transmitter in operative communication with the controller circuit;
• a receiver in operative communication with the controller circuit;
• and
• a memory;
• wherein the controller circuit is configured to:
• cause the transmitter to transmit a first encrypted message including a first fixed code and a first changing code;
• cause the receiver to receive a response from the second device in response to the transmitted first encrypted message;
• decrypt the response received by the receiver;
• determine a second fixed code based on the decryption of the response;
• cause the second fixed code to be stored in the memory;
• cause the transmitter to transmit a third encrypted message including the first fixed code and a changed version of the first changing code;
• cause the receiver to receive a fourth encrypted message from the second device in response to the transmitted third encrypted message;
• decrypt the fourth encrypted message received by the receiver;
• determine the second fixed code and a second changing code based on the decryption of the fourth encrypted message;
• validate the fourth encrypted message by confirming that the second fixed code determined from the response and stored in the memory matches the second fixed code determined from the fourth encrypted message;
• and
• store the second changing code in the memory based on validating the fourth encrypted message.

A second device configured to be paired to a first device to effect secure communication between the first device and the second device, the second device comprising:

• a controller circuit;
• a transmitter in operative communication with the controller circuit;
• a receiver in operative communication with the controller circuit;
• and
• a memory;
• wherein, when the second device is set to a learn mode, the controller circuit is configured to:
• cause the receiver to receive a first encrypted message from the first device,
• decrypt the first encrypted message received by the receiver;
• based on the decryption of the first encrypted message, determine a first fixed code and a first changing code;
• store the first fixed code and the first changing code in the memory;
• cause the transmitter to transmit a response including a second fixed code;
• cause the receiver to receive a third encrypted message from the first device in response to the transmitted response;
• decrypt the third encrypted message received by the receiver to;
• based on the decryption of the third encrypted message, determine the first fixed code and a changed version of the first changing code;
• validate the third encrypted message by confirming the first fixed code determined from the third encrypted message matches the stored first fixed code and the changed version of the first changing code determined from the third encrypted message matches an expected value of the stored first changing code;
• store the changed version of the first changing code in the memory based on validating the third encrypted message;
• and
• cause the transmitter to transmit a fourth encrypted message that is receivable by the first device, the fourth encrypted message including the second fixed code and a second changing code in response to validating the third encrypted message.

The method of 31, further comprising:

• upon pairing the first device and the second device:
• receiving, by the second device, while the second device is in an operation mode, a
• request from the first device to perform an action;
• and
• effecting performance of the action by the second device.