Following on the heels of breathless coverage of consumer Internet of Things (IoT) applications -- think home thermostats, wearable fitness trackers, or smartphones controlling any number of common devices -- the Industrial Internet of Things (IIoT) is now also garnering some well-deserved attention.

Market research firm IHS predicts that the IIoT will add 500 million new units per year through 2017. Economists from industrial giant GE have been quoted as estimating that the wave of innovation unleashed by the industrial Internet could boost global GDP by as much as $10 trillion to $15 trillion over the next 20 years. GE itself has reportedly already generated about $800 million in revenue from industrial Internet-related sales, up from $290 million last year. And news about the recently formed Industrial Internet Consortium has boosted attention and credibility for this fast-evolving sector.

Still, it's important to note that the IIoT is not simply a version of the consumer IoT happening on a factory floor somewhere. IIoT use cases might include transit braking systems, energy grids, and elevators, as well as factories. As a rule, the IIoT has far more stringent requirements than the consumer IoT, from non-negotiable reliability and security to scalability, peer-to-peer device operation, and the ability to operate autonomously, without human intervention, in often-inhospitable environments.

Of all the differences between consumer and industrial device requirements, however, one of the most overlooked is longevity. Industrial automation has been around for a long time, and many industrial devices predate the Internet of Things terminology by decades. In fact, the IIoT has a billion or so long-lived devices already operating on various control networks across the globe.

Not surprisingly, multiple protocols have evolved to meet the needs of specific industrial environments and communities of devices. These legacy industrial devices don't intercommunicate outside of their own discrete control networks, and they were typically installed prior to widespread Internet Protocol (IP) integration.

If the glowing IIoT predictions are to become reality, there must be a concerted effort to bring these legacy industrial devices into the fold -- to enable them to remain relevant to an IoT world while still meeting all the specialized requirements of their industrial environments.

Just as the Internet's flourishing depended on bridging the disparate networks connecting PCs of the 1980s, so too, the flourishing of the IIoT depends on industrial device networks' ability to intercommunicate, even in the face of incompatible protocols and connectivity media. And as with the Internet, the bridging protocol can be IP.

Currently, industrial systems connect to the Internet and internal IP networks through gateways, which require custom provisioning and programming to expose the necessary data to enterprise systems. Invariably, the gateway constrains what information is able to pass back and forth, and its configuration is difficult to evolve to support new requirements.

For industrial networks, a number of interrelated technical shifts are enabling legacy devices to take advantage of IP sacrificing the functionality provided by the legacy protocols:

Design engineers tasked with creating robust, effective, and affordable devices and applications for the IIoT can use new tools such as the IzoT platform for the IIoT for both greenfield and legacy situations. (See: IzoT Connects Industrial IoT.)

Successful industrial control networking solutions must recognize and embrace the special considerations of the industrial world while building IP-based bridges to the IIoT. This includes myriad existing protocols, devices installed for their reliability and longevity, and the need for both wired and wireless connections. In this way, all those legacy industrial devices already connected on various incompatible networks can co-exist alongside newly developed and already IP-enabled industrial devices, so that all can participate in the alluring opportunities presented by the IIoT.

Varun Nagaraj is the senior vice president and general manager, for the commercial and Internet of Things markets at Echelon.

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