Patent attributes
A re-programmable wireless cryptographic device can store data securely and use near field communication (NFC) to exchange functionality data and/or program code from a central server system through a mobile device. A user requests a new cryptographic device or a new device function via an application on the mobile device. The central server system transmits program code and a public key used to identify the cryptographic device to the mobile device, which functions as a pass-through conduit for the information, storing it until the devices are synced. A NFC communication channel is created, and the mobile device authenticates the cryptographic device by cross-referencing the public key received from the central server system with the public key transmitted by the cryptographic device once the communication channel is established. Upon authentication, the cryptographic device is synced with the mobile device, and the mobile device passes the program code to the cryptographic device.