IT-to-OT Solutions That Can Bolster Security in the IIoT

First of a two-part series.

The Industrial Internet of Things (IIoT) — within companies and across the entire global IIoT ecosystem — is an intricately intertwined and negotiated merger of information technology (IT) and operational technology (OT). OT systems are not only business-critical, they can be nation-critical or life-and-death-critical. Unfortunately,  the convergence of IT and OT has created uncertainty within companies about the ownership and operation of OT security solutions, as have many disruptive evolutions. The result: an alarming 59% of companies are willing to "tolerate medium-to-high risk in relation to IoT security," according to Forrester. This is dangerously wrong.

As someone with experience on both sides of the IT/OT equation, I've realized how industrial companies can use the hard-won, long-fought lessons of IT to leapfrog to an advanced state of IIoT security — architected and deployed to meet OT's differentiated requirements. If one thinks of OT systems as another form of data center — the heavily protected core of enterprise IT — there are some promising ideas one can adapt from decades of IT experience to provide new levels of IIoT security while honoring the specific needs of OT. Here are three examples.

Separation of Endpoint Networks
IT has learned the security advantage of separating endpoint networks of PCs and mobile devices from the core data center. As people carry their company laptops around, they can get hooked on the addictive drug known as free Wi-Fi — connection anywhere. It's free, but dangerous. Those endpoints can easily become compromised.

So, IT has developed "border crossings" that separate endpoint networks from the data center until PCs and laptops pass rigorous vetting. Not just usernames, passwords, and authentication codes but complete border-crossing-style background checks: Where has that machine been? What has it been doing? What software is loaded on it? Has the machine been compromised by travel to countries known for cyber espionage? Levels of access to the data center are provided in keeping with the results of a machine's background check.

The number of users, and therefore endpoint machines, is smaller in OT than in IT, but the same separation, vetting, and "border crossing" background checks can be used to strengthen OT security, and thus the security of the entire IIoT enterprise.

Microsegmentation
Data centers are comprised of multiple machines. Traditionally, when users access the data center via one machine, they can access all machines. But in most cases, there's no need for a free-for-all in which every user can access every machine. Via microsegmentation, security officers study the interrelationship of machines to determine which machines must talk to which other machines, and they restrict access to necessary connections only. This materially reduces vulnerability and potential damage.

Much as we'd like to, it's impossible for anyone to guarantee 100% fail-safe IIoT security. Therefore, we harden what we can, and reduce attack surfaces to the bare minimum. By dividing networks into physically independent microsegments, we build security walls within security walls — on the assumption that bad guys will be able to get through one or two but not all of them. 

The good news in porting microsegmentation from IT to OT is that OT is in many ways a simpler world. Where IT is comprised of fluid technology stacks with multiple moving parts dedicated to the three-dimensional flow of data, OT systems are engineered primarily to optimize processes: things happen the same way all the time to produce a specific output from a specific input. Modularity and mass customization are making OT more like IT every day, but for now it's safe to say that OT systems are simpler, making mirosegmentation easier to initiate and operate.

As the number of potentially lethal anti-IIoT malware variants increases, we need to develop and install as many trigger monitors as possible. Separation of endpoint networks and micro-segmentation could be valuable security additions to the OT half of the world's industrial economy. 

Read Part Two: User Behavior Analytics Could Find a Home in the OT World of the IIo

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