Patent ID: 7069445
Filing Date: 2006-06-27
Classification: G06F

Abstract:
1. A method for booting a computer system with first and second versions of a bootable program comprising the steps of: loading said first and second versions of said bootable program into first and second partitions of a storage device coupled to said computer system; hashing a boot record (BR) of said first and second versions of said bootable program producing respective first and second digests; signing said first and second digests using a cryptographic signature engine and a private installation key producing first and second signatures; storing said first and second signatures with additional data defining said first and second versions of said bootable program in first and second entries in a non-volatile memory coupled to said computer system; assigning said first partition as an active partition of said storage device by updating an active partition entry of a partition table of a master boot record (MBR) of said storage device, said active partition entry indicating which version of said BP is booted on a power up of said computer system; assigning said first entry corresponding to said first version of said bootable program as an active entry in said non-volatile memory; and assigning said second entry corresponding to said second version of said bootable program as an alternate entry in said non-volatile memory.