Identification and authentication of multiple controllers

An identification and authentication system comprising:

• a plurality of controllers including a first controller having a first device certificate and a second controller having a second device certificate, the first device certificate having a first user identifier and a first set of device control privileges, and the second device certificate having a second user identifier and a second set of device control privileges that is different from the first set of device control privileges;
• and
• an embedded device including:
• an embedded device memory;
• and
• an embedded device processor configured to:
• obtain, from the first controller, the first device certificate;
• obtain, from the second controller, the second device certificate;
• extract, from the first device certificate, the first user identifier and the first set of device control privileges;
• extract, from the second device certificate, the second user identifier and the second set of device control privileges;
• compare the second user identifier with the first user identifier to authenticate access to the embedded device for the second controller without connectivity to a server;
• determine whether the second user identifier within the second device certificate is the same as the first user identifier within the first device certificate;
• and
• allow or prevent access to the embedded device by the second controller based on the determination and the extracted second set of device control privileges.