High speed fiber optics backbones

In late 1995, the data communications networks at the Fletcher Challenge Canada's Crofton pulp and paper mill had reached capacity and were suffering from overload. The large growth in process control information and personal computers over the past few years was straining the abilities of existing coaxial and fiber optic systems to reliably transfer data. In addition, increased network complexity made troubleshooting the networks extremely difficult and time-consuming. This article discusses the design methods used to create a new fiber optic backbone to provide the data carrying capacity and reliability needed for the pulp and paper mill's computers and control systems. High-speed network technologies such as ATM (asynchronous transfer mode), FDDI (fiber distributed data interface) and fast Ethernet were compared for their suitability in industrial environments. The design also incorporated Ethernet switches so that the existing Ethernet networks could attach at minimal cost. These switches subdivided the original single large network into approximately 24 sub-networks. This division greatly increased the network's allowable traffic capacity and prevented problems in any one area from propagating throughout the mill, and thereby reduced network and process downtime     

Designing secure networks for process control

In most industrial plants, there is a strong drive to provide business applications with some access to real-time data generated from process control systems. Often, this has been in the form of a process historian database server connected to both the distributed control systems/programmable logic controller (DCS/PLC) systems and the business users. It can also take many other forms such as remote X-Windows sessions from the DCS, or direct file transfers from PLCs to users spreadsheets. Regardless of the method, it involves a network connection to both the process and the business side. These network connections are increasingly Ethernet based on both sides, rather than proprietary industrial protocols. At the same time, most control systems now use Ethernet networking as a critical component of their system architecture. This can be for controller-to-controller communications, controller-to-operator console communications or even I/O-to-controller communications. Losing any of these links will directly impact production. The issue is that problems on the business network can be passed on to the process network through this process data link, seriously impacting production. Protecting that process system from external network problems is the focus of this article     

Process control using a fiber-optic unified cabling systems

In an ideal world, communications cabling for process control would be simple-buy all the computer, instrumentation, and electrical equipment from a single vendor, and connect it all together using a single cabling standard. But real life is never that simple; rarely are the programmable logic controllers (PLC), distributed control systems (DCS), drives, motor controls, field instrumentation, and computers all purchased from the same vendor. Supplying power to all this different equipment certainly doesn't require separate cabling structures, so why shouldn't the same be true for communications needs? Wouldn't a standard cabling infrastructure minimize the cabling infrastructure cost and complexity? The engineering group of a Canadian pulp and paper mill wondered about these two questions. They were designing a new steam plant and decided to investigate the possibility of making a single process communication cabling "utility" through the plant. The result was a design methodology that allowed a standardized cabling system to serve all communications needs throughout the process areas. Fiber-optic cable was chosen for all communications cabling outside of the control or electrical rooms. While the noise immunity and high data carrying capacity of fiber-optic cable was a factor, the primary reason was that fiber-optic cabling was the only system that could provide a single medium suitable for the very wide range of communications equipment in the mill     

Industrial cybersecurity for a power system and SCADA networks - Be secure

This article presented an overview of the security vulnerabilities of today's industrial control networks. These vulnerabilities exist despite abundant information, standards, and recommended practices published by such organizations as the IEC, IEEE, and ISA. While a good understanding of the issues is required to appreciate the problem, the good news is that it does not take long for the plant engineering forces to get up to speed on the network issues surrounding cybersecurity. Unfortunately, the same can be said for the hacker. Many incidents have occurred and even more are yet to come. Existing systems are vulnerable but can be secured. Given the resources available, future systems can be made secure from the start. Assessing the existing network is straightforward. Producing a human assessment, device inventory, and network diagram is the first step. The development of sensitive assessment tools that can gather the required information, but not affect the- process computers, is also required. All information is gathered, entered into a database, analyzed, and then compared to industry best practices.