Impact of local and wide area networks on SCADA and SCADA/EMS systems

Local and wide area computer networks have provided the means for utility SCADA and SCADA/energy management systems to distribute functions over many interconnected processors. This has enabled users to avoid obstacles historically encountered when expanding capabilities in local control systems and when maintaining geographically dispersed data bases at remote control centers. These features also lead to improvements in processing performance, fault tolerance, maintenance and programming simplification and life cycle cost reduction. The authors review the improvements which are being, or have been, incorporated into recent utility installations. Specification suggestions are offered for achieving a truly distributed local area network (LAN) system