The notion that program design is an engineering task alleviating the software crisis has been with us for about a decade. With the recognized advantages of obeying to certain software design disciplines, we are approaching the era of enforced system development standards which will ensure that end products will meet rigorous design requirements. On the one hand, advances in system architecture fUrther the application of system development standards to software and firmware design and production. On the other hand, the growth in complexity of future system architectures, in particular distri...