US Patent 9886571 Security enhancement of customer replaceable unit monitor (CRUM)

A component subsystem and a method for authenticating the component subsystem. The component subsystem may be installed in a host device. The method can include an authentication protocol, wherein the host device sends a test voltage value to the component subsystem which, in turn, generates a test voltage based on the test voltage value. The test voltage is applied to a test cell that includes a wordline, a bitline, and a memory film. A response voltage is read from the bitline and compared to an expected value. If the response voltage matches the expected value, host device and/or component subsystem functionality is enabled. If the response voltage does not match the expected value, the host device and/or component subsystem functionality is disabled.