Apple files for code signing, almost-symmetric multiprocessor patents
Patent number EP1695169 for a "method and apparatus for incremental code signing" is for a method for authenticating a large computer platform. The system operates by first sealing the computer program with a digital signature in an incremental manner. Specifically, the computer program is divided into a set of pages and a hash value is circulated for each page. The set of hash values is formed into a has value array, and then the hash value array is sealed with a digital signature. The computer program is then distributed along with the hash value array and the digital signature. To authenticate the program, a recipient first verifies the authenticity of the hash value array with the digital signature and a public key. Once the hash value array has been authenticated, the recipient can then verify the authenticity of each page of the computer program by calculating a hash of a page to be loaded and then comparing with an associated hash value in the authenticated hash value array. If the hash values don't match, the execution may be halted. The inventors are listed as Perry Kiehtreibert and Michael Brouwer.
Patent number EP1695216 for almost-symmetric multiprocessor that supports high-performance and energy-efficient execution" is for a system for controlling the execution of tasks in a multiprocessor system, which contains both a high-performance processor and an energy-efficient processor. Upon receiving a task to be executed on the multiprocessor system, the system determines whether to execute the task on the high-performance processor or the energy-efficient processor based on performance requirements for the task and/or energy usage considerations for the multiprocessor system. Next, the system executes the task on either the high-performance processor or the energy-efficient processor based on the determination. The inventors are listed as William C. Athas, Robert L. Mansfield, Lynn R. Youngs and Michael F. Culbert.