Patent ID: 11895251
Assignee: ASSA ABLOY AB
Field: Digital communication (Electrical engineering)
Classification: CPC H | IPC H

Claim 10:
11. A receiver device of an authentication system, the receiver device comprising:
physical layer circuitry; and
processing circuitry operatively coupled to the physical layer circuitry and configured to:
decode an authentication command received from a verifier device for authenticating the receiver device;
encode a response for sending to the verifier device in response to the authentication command, wherein the response includes a first random number determined by the receiver device in response to the authentication command using a counter value and by updating the counter value for each communication session between the verifier device and the receiver device;
determine receiver device keying material using a static encryption key specific to the receiver device and the first random number;
decrypt encrypted information received from the verifier device, wherein the encrypted information includes the first random number, the second random number, and verifier device keying material specific to the verifier device;
encrypt the first random number, the second random number and the receiver device keying material for sending to the verifier device according to a script included in the receiver device, wherein the receiver device keying material includes a third random number predictable by the verifier device using the first random number, the second random number and the verifier device keying material specific to the verifier device; and
calculate a session encryption key using the static encryption key, the verifier device keying material and the receiver device keying material.