Enabling program code on target data processing devices

A method of enabling program code stored on target data processing devices, the method comprising:

• receiving a smartcard on which are stored a value of a permitted number of target data processing devices that are permitted to have program code stored on them enabled and instructions for execution by the smartcard to generate a license key from a device identifier;
• and
• for each target data processing device, using the smartcard to:
• determine whether the value of the permitted number of target data processing devices is greater than zero;
• if so, obtain a device identifier from the target data processing device;
• generate a license key from the device identifier;
• store the license key on the target data processing device;
• and
• decrement the value of the permitted number of target data processing devices.

A security data processing device comprising a processor and a memory, the security data processing device configured to:

• receive an encrypted value of a permitted number of target data processing devices that are permitted to have program code stored on them enabled;
• decrypt the encrypted value and store the decrypted value in said memory;
• receive encrypted instructions for execution by the security data processing device;
• decrypt the encrypted instructions and store the decrypted instructions in said memory, and execute the decrypted instructions on said processor to:
• determine whether the value of the permitted number of target data processing devices is greater than zero;
• if so, obtain a device identifier from a target data processing device;
• generate a license key from the device identifier;
• store the license key on the target data processing device;
• and
• decrement the value of the permitted number of target data processing devices.