The multi-layered design diversity architecture: application of the design diversity approach to multiple system layers

The multi-layered design diversity (MLDD) architecture achieves fault tolerance to design faults of application programs, operatoring systems, and hardware components through applying the design diversity approach to these three system layers. The introduction of design diversity into multiple system layers improves system reliability. However, its enormous costs makes it impractical. The authors solve this problem through the fact that the TRON Project standardization approach to achieve compatibility among systems is same as that of the design diversity approach. In order for the MLDD architecture to be effective in improving system reliability, a probability of a coincident error, that is, two or more independently developed implementations failing on the same input, must be low. A low coincident error rate can be achieved by using sufficiently high quality development procedures for real-life applications and different testing methods for developing multiple implementations