ABSTRACT
The system architecture primarily designates the system structure, namely, how the system is organized, how its elements and the communication links are related to each other, etc. It also designates the system hardware and software configuration, that is leveraged to solve complex automation problems, based on a specific design philosophy. Decentralized, hierarchically organized automation systems, although being conceptually very sophisticated and structurally transparent, have to be seen as systems whose original implementation has been relatively involved. This chapter focuses on the organisation and allocation of system functions at different hierarchical levels. It considers the organisation of data within a hierarchically structured system and discusses problems of its generation, access, up-dating, protection, and transfer between different hierarchical level of the system. Application of a process control computer requires a series of interfaces for interaction between the computer system and the experts preparing, testing, integrating, operating, and maintaining its software and hardware.
