A method of determining trust in a supply item in an imaging device for verifying other supply items installed in the imaging device via an algorithm, wherein the imaging device has a plurality of installed supply items. The method comprises: sending challenge data and an indication of the algorithm to a candidate supply item, receiving a challenge response from the candidate supply item, and determining, by the controller, a status of the challenge response, the status being verified or unverified. When the controller determines that the received challenge response is a correct output of the algorithm when the challenge data is input to the algorithm, the status is determined as verified. Further, an imaging device configured to determine trust in a supply item installed in the imaging device for verifying other supply items installed in the imaging device via an algorithm.

An image obtaining device includes a communication interface configured to communicate with a terminal and a controller in communication with the communication interface. The controller configured to: generate encrypted image data using an encryption key and image data received by the controller, transmit the encrypted image data to the terminal via the communication interface; and transmit the encryption key to the terminal via the communication interface in a first situation, wherein the encryption key is not transmitted to the terminal in a second situation different from the first situation.