Abstract: A base portion of an electronic apparatus and a plurality of eligible smart interchangeable covers are provided with corresponding instructions for the base to authenticate an attached cover. The base operates the apparatus at a function/feature level in view of whether the base is able to authenticate the cover. In one embodiment, the authentication involves exchange of challenges and responses between the base and the cover, employment of session keys to facilitate the exchanges via encrypted communications, employment of private and public keys of the cover to facilitate provision of the session key(s) to the cover, and employment of a certificate to facilitate provision of the public key of the cover to the base. In one embodiment, the challenges/responses comprise at least a subset of the functions/features implementing instructions/data of the cover, and the certificate is signed by a common licensor of the vendors of the base and the covers.