A barcode reader and an accessory are disclosed. A barcode reader may include an interface for communication with a host computer via a wireless or wired link and an authentication system to establish mutual authentication with the host computer. The barcode reader may include a connector for connecting the barcode reader to the external power source or the host computer. The connector may be a combined power and data connector. An accessory may provide operating power to a barcode reader and provide decoded data of an image of a barcode received from the barcode reader to a host computer. The accessory may include connectors and an interface system. The interface system may include a processor configured to send the decoded data to the host computer, an authentication system, and a power interface. The accessory may include RF circuits for communicating with the host computer via a wireless link.