Patent ID: 8161567

Claim:
An accessory device for a portable electronic device, comprising: an input/output port for interacting with the portable electronic device; an authentication controller operatively connected to said input/output port, the authentication controller being implemented within a single integrated circuit chip, wherein the authentication controller is configured to: receive a random number from the portable electronic device; encrypt the random number with a first key associated with the accessory device to generate an encrypted random number; communicate the encrypted random number to the portable electronic device; and receive indication from the portable electronic device of whether the accessory device is authenticated or not based at least in part on the encrypted random number; and accessory circuitry configured to: access a limited set of functions of the portable electronic device through the input/output port in response to a failed authentication; and access a full set of functions of the portable electronic device through the input/output port in response to a successful authentication, wherein the limited set of functions includes fewer functions than the full set of functions, and wherein the limited set of functions includes at least one function.