Serial architecture for high assurance processing

A system for processing payload data comprising:

• an input interface configured to receive said payload data, compute a first digest using said payload data and a first parameter, and generate a first message that includes said payload data and said first digest;
• a first processor in communication with said input interface and configured to receive said first message from said input interface, process said payload data contained in said first message to produce first processed data, compute a second digest using said first digest, said first processed data, and a second parameter, and generate a second message that includes said payload data and said second digest;
• a second processor in communication with said first processor and configured to receive said second message from said first processor, process said payload data contained in said second message to produce second processed data, compute a third digest using said second digest, said second processed data, and a third parameter, and generate a third message that includes said second processed data and said third digest;
• and
• an output interface in communication with said second processor and configured to receive said third message, compute a validation digest using said third digest, said second processed data contained in said third message, and a fourth parameter, and output said second processed data when said validation digest matches a predetermined value.

A method of processing payload data comprising:

• serially arranging an input interface, a first processor, a second processor, and an output interface so that an output port of one of said input interface, said first processor, and said second processor is coupled with an input port of a successive one of said first processor, said second processor, and said output interface;
• at said input interface, computing a first digest using said payload data and a first parameter and generating a first message that includes said payload data and said first digest;
• at said first processor, receiving said first message from said input interface, processing said payload data contained in said first message to produce first processed data, computing a second digest using said first digest, said first processed data, and a second parameter, and generating a second message that includes said payload data and said second digest;
• at said second processor, receiving said second message from said first processor, processing said payload data contained in said second message to produce second processed data, computing a third digest using said second digest, said second processed data, and a third parameter, and generating a third message that includes said second processed data and said third digest;
• and
• at said output interface, receiving said third message from said second processor, computing a validation digest using said third digest, said second processed data contained in said third message, and a fourth parameter, validating redundant processing of said payload data at said first and second processors when said validation digest matches a predetermined value, and outputting said second processed data when said fourth digest matches said predetermined value.