Patent ID: 8652126

Claim:
A method for authenticating a physiological sensor, the method comprising: examining, in response to a sensor being connected to a patient monitor, whether a first sensor-specific usage count of the connected sensor is greater than or equal to a second sensor-specific usage count of the connected sensor, wherein the first and second sensor-specific usage counts are indicative of cumulative usage of the connected sensor and wherein the first sensor-specific usage count is stored in the connected sensor and the second sensor-specific usage count is stored in a host memory external to the connected sensor; allowing use of the connected sensor in the patient monitor when the examining indicates that the first sensor-specific usage count is greater than or equal to the second sensor-specific usage count for the connected sensor; rejecting the use of the connected sensor in the patient monitor when the examining indicates that the first sensor-specific usage count is less than the second sensor-specific usage count of the connected sensor; and updating the first and second usage counts for the connected sensor in response to the use of the connected sensor in the patient monitor, thereby to keep the first and second sensor-specific usage counts of the connected sensor consistent and updated for a subsequent use attempt of the connected sensor.