From its beginnings in the 1960s, SCADA—Supervisory Control and Data Acquisition—has been evolving along with the computer industry. From monolithic systems running on mainframes, SCADA moved to distributed processing on mini computers linked over a LAN, and more recently to PCs and open standards such as TCP/IP. Now what? Everyone in the IT world is talking about cloud computing as the next big thing. What does that mean for SCADA? Will it evolve to the cloud?
At first glance, it doesn't seem likely. Most industry experts agree it would be foolish to put the primary control of a power plant, water treatment system, or rail yard switching system on the cloud. These kinds of mission-critical control tasks require rugged, reliable data networks and extremely fast response times. Advocates of cloud computing may hope that Internet speed, reliability, and security will eventually support this level of SCADA, but we have no guarantees of that right now.
That said, there is a growing demand for process data beyond the shop floor. Although the primary functionality of a SCADA system is to acquire process data and relay supervisory control messages, it is not difficult to envision secondary uses for the data. Why not provide the process data to those key people in the company or along the supply chain who might find it valuable?
A number of SCADA vendors already offer web-based HMI connections to their systems to give operators, engineers, and managers a view of live process data in a web browser. A properly designed cloud system could provide these decision-makers with broader access to the data at significantly less cost than traditional SCADA expansion options.
Managers, analysts, and other specialists are best able to examine the workings of a process in real-time. This gives them faster insight into the process, and the ability to work with and react to the true behavior of the system. A cloud system, properly implemented, can provide data rate and latencies in milliseconds. This can be crucial to a remote engineer when trying to study high-speed transients and process dynamics, or reduce downtime.
Providing this kind of access to process data naturally raises questions about security. Fundamental to the discussion is the need to keep critical processes completely secure from hackers and unwanted intruders prowling the Internet. At the very least, any cloud-based SCADA enhancement must be able to operate without opening any ports in a firewall. This requires a substantial rethinking of the traditional client/server roles in a typical SCADA system, but it can be done.
The benefits of cloud-based connectivity will continue to entice decision-makers who are looking for a competitive edge. The increased globalization of production is making it necessary to gain access to process control systems from remote locations. A company may be eager to off-shore their production, but not so willing to off-shore their technical expertise. Remote monitoring systems allow companies to take advantage of the low costs of production in other countries (often with lower standards of legal and IP protection) without exposing their corporate expertise and trade secrets to those countries.
As the IT world accelerates its move towards cloud computing, and plant engineers get more comfortable with the idea, the benefits of enhancing SCADA with cloud-based capabilities will become more apparent. The advantages of providing key people with controlled access to critical real-time data in a secure, reliable, and affordable way will put forward-thinking companies one step ahead of the competition.
For more information about Cogent Real-Time Systems, visit http://www.cogentdatahub.com/.
