Patent ID: 8230412

Claim:
A computer implemented method for establishing an operating environment of a device, the method comprising: executing a first executable code image in a memory of a device in an attempt to establish an operating environment of the device, the first executable code image being associated with a first version number; the first executable code image, which when executed from the memory, authenticating a second executable code image, which when successful, to retrieve a second version number from the second executable code image; and the first and second executable code images mutually verifying compatibility between the first and second code images, wherein the mutual verification is capable of preventing the second executable code image from being loaded by the first executable code image if the first version number and the second version number do not satisfy a predetermined relationship and wherein the mutual verification interrupts execution of the second executable code image if the first and second version numbers do not satisfy the predetermined relationship and the second executable code image is loaded by the first executable code image.