It has been envisioned that the next generation industrial controls should provide an open
architecture and a single software development environment ta. The trend will be to move away from
closed, proprietary systems I6] due to the advantages an open architecture provides fgl. It gives more
flexibility since users do have to "marry" to a particular supplier [1°]. There is easier access to the latest
technology since numerous independent developers are continuously advancing the functionality and ease
of use of PC-compatible hardware and software. Also, it provides cost effectiveness because its large
market ensures a competitive environment and economies of scale that drive prices to their lowest level.