The Industrial Internet of Things, or IIoT, will soon enter the mainstream of business and industry (see Fiber and the Industrial IoT). Unlike consumer IoT applications, security and reliability are not just important – they are critical in industrial applications.

That’s probably the main reason why we’re beginning to see a lot of fiber optic communications in the IIoT space. By keeping control and monitoring signals on a private fiber circuit, away from the public internet, the chances of someone “hacking” into these critical systems are dramatically reduced. People can’t hack what they can’t see. While copper lines can be bridged by snooping devices and still operate, it isn’t possible to “tap into” a fiber line without it affecting communications. Even though it can be as thin as a human hair, a fiber optic strand in a cable is still just glass.

Then there’s the raw speed of fiber transmission; fiber ensures on-time delivery of crucial commands and queries. Since signals are not being sent over a network that is carrying millions of other signals, there’s no packet delay or “stutter.” Fiber is also immune to transmission problems caused by electromagnetic interference (important in power generation facilities or near equipment that produces electromagnetic signals), and it can be installed in many places, including underwater.

Another compelling reason why fiber is becoming so popular is the sheer amount of information that can be carried on a single link. This is often achieved with an optical multiplexer, such as the FiberPlex WDM16, which splits the huge bandwidth of fiber into smaller chunks that can then be dedicated to specific purposes. This means that in addition to serial data transfer, the same strand of fiber optic cable you use for IIoT device control can be used for video monitoring of the facility, with uncompressed HD video for maximum resolution. Range is rarely an issue for fiber. SCADA sensors, for example, are connected to terminals and controllers, and many of those terminals are connected to external supervisory systems. With fiber transmission, those external supervisory systems could be located across the plant – or across the country.

Even outside heavy industry, most industrial devices offer some type of external access – usually a serial interface - for control and monitoring. The most common serial interfaces for small industrial devices are Ethernet, Serial or GPI/O (General Purpose Input/Output pins connected directly to the device’s processor). To connect these to a fiber network, you’ll need an interface of some sort, which takes the digital signals presented on the connectors and translates them to a light signal. At the other end of the transmission path, a similar device is needed to convert the light signal back to the signal your controller or monitoring system needs.

Serial-to-fiber interfaces, patented waveguides to keep external EMI/RFI away from sensitive data collection equipment, alarm and alert modules, video interfaces and other devices are available.