A communication device employs a contactless secure communication interface to transmit and receive data with a computing device using close proximity extremely high frequency (EHF) communication. The communication device and the computing device periodically initiate a discovery operation mode, whereby the devices periodically transmit identifying information about the respective devices and listen for identifying information from the other device. Upon completion of the discovery mode operation, the devices enter a link-training operation mode and exchange capability information about the respective devices. During transport mode operation the communication device employs methods to manage access to data stored on the communication device by encrypting the data using one or a combination of training information or capability information as a basis for generating an encryption key.