An apparatus for providing link layer security in a Physical Layer Transceiver (PHY) is disclosed. In one embodiment, the apparatus may comprise analog circuitry configured to interface with a data transmission medium, digital circuitry configured to interface with a Media Access Controller (MAC); and a crypto engine coupled to the digital circuitry. Single interface and multiple interface schemes are provided to control both PHY and crypto functions. Embodiments are disclosed where the PHY controls the crypto device, and where the crypto device controls the PHY.