Method and system for command authentication to achieve a secure interface

A non-transitory machine-readable storage having stored thereon, a computer program having at least one code section for secure communication in a device, the at least one code section being executable by a machine for causing the machine to perform steps comprising:

• in a slave device:
• receiving from a host device, a host device key that is generated by said host device based on a host root key and at least one control word stored within said host device, wherein said host device is configured to generate said host device key only once;
• generating by said slave device, a slave device key based on said received host device key, a slave root key, and at least one control word stored within said slave device;
• and
• authenticating by said slave device, commands received from said host device utilizing said generated slave device key.

A system for secure communication in a device, the system comprising:

• a slave device that is communicatively coupled to a host device, said slave device enables generation of a slave device key based on a host device key received from said host device, a slave root key, and at least one control word stored within said slave device, wherein:
• said host device generates said host device key based on a host root key and at least one control word stored within said host device;
• and
• said host device is configured to generate said host device key only once;
• and
• said slave device enables authentication of commands received from said host device utilizing said generated slave device key.