摘要 |
A communication protocol between a master device, such as a mobile phone, and a peripheral device facilitates authentication of the peripheral device. When a peripheral device is detected, the master device initiates a wake-up command to the peripheral device, transmits an authentication request command followed by challenge data to the peripheral device, and awaits responses from the peripheral device. The accessory receives the challenge data, performs a hash function on the challenge data, and generates response data. An authentication response type byte is sent to the handset followed by the response data. The handset compares the response data to pre-stored data that is associated with the challenge data. A match indicates that the accessory is authentic. The challenge/response data, also referred to as a plaintext/cyphertext pair, is pre-generated external to the handset using the hash function, then pre-stored in the handset. |