Open Control Systems integration issues

Security issue is one of the most important aspects in the current design of SIS. With the help of an open interface like Open Platform Communications (OPCs) (Fig. XI/4.0 1) it is possible to integrate not only BPCS and SIS but the entire en terprise network. Common and open communications protocol architecture stan dards are replacing the diverse and disparate proprietary systems of industrial control systems. This migration empowers users to access new and more efficient methods of communication as well as more robust data, quicker time to market, and... 

While the main thrust of these analyses are to provide a plant that exhibits satisfactory closed-loop performance, the assumptions regarding the control system vary considerably across the various methods proposed. The open-loop indicators are largely based on factors that limit achievable closed-loop performance independent of controller type, whereas most of the optimization based integrated design formulations assume a specific controller type such as multiloop PI, LQG and so forth. While this is not considered to be a problem per se, it is important that the implications of these assumptions are clear so that appropriate deductions may be drawn. This chapter attempts to at least in part address this issue. 

---