A replaceable printer component comprising: a first memory device configured to store a first secret; and a communication link configured to communicatively link the first memory device to a printer controller when the replaceable printer component is installed in a printing system; wherein the first memory device is configured to: generate a session-key identifier and a first session-key based on the first secret and provide the session-key identifier to a second memory device of the printing system in response to a request, receive a read request to a data field storing a value indicating the authenticity of the replaceable printer component, the read request including a first message authentication code calculated using a second session-key, calculate a second message authentication code based on the read request and the first session-key, and perform the read request in response to the second message authentication code matching the first message authentication code, wherein the first memory device is configured to deny the read request and to mark the first session-key as invalid in response to the second message authentication code not matching the first message authentication code and the first memory device is configured to perform the read request by providing a response including the value indicating the authenticity of the replaceable printer component and a third message authentication code calculated over the value indicating the authenticity of the replaceable printer component using the first session-key. a first memory device configured to store a first secret; and a communication link configured to communicatively link the first memory device to a printer controller when the replaceable printer component is installed in a printing system; wherein the first memory device is configured to: generate a session-key identifier and a first session-key based on the first secret and provide the session-key identifier to a second memory device of the printing system in response to a request, receive a read request to a data field storing a value indicating the authenticity of the replaceable printer component, the read request including a first message authentication code calculated using a second session-key, calculate a second message authentication code based on the read request and the first session-key, and perform the read request in response to the second message authentication code matching the first message authentication code, wherein the first memory device is configured to deny the read request and to mark the first session-key as invalid in response to the second message authentication code not matching the first message authentication code and the first memory device is configured to perform the read request by providing a response including the value indicating the authenticity of the replaceable printer component and a third message authentication code calculated over the value indicating the authenticity of the replaceable printer component using the first session-key. generate a session-key identifier and a first session-key based on the first secret and provide the session-key identifier to a second memory device of the printing system in response to a request, receive a read request to a data field storing a value indicating the authenticity of the replaceable printer component, the read request including a first message authentication code calculated using a second session-key, calculate a second message authentication code based on the read request and the first session-key, and perform the read request in response to the second message authentication code matching the first message authentication code, wherein the first memory device is configured to deny the read request and to mark the first session-key as invalid in response to the second message authentication code not matching the first message authentication code and the first memory device is configured to perform the read request by providing a response including the value indicating the authenticity of the replaceable printer component and a third message authentication code calculated over the value indicating the authenticity of the replaceable printer component using the first session-key.