IT and OT networks have converged, new technologies have been deployed, and resources remain constrained. Now more than ever, organizations need a strong security strategy to protect and defend their networks against adversaries.
The first step in implementing a new security strategy is improving network visibility. You can’t secure what you can’t see!
In this blog and the series that follows, we’ll discuss methods and techniques for improving the overall visibility fabric.
Network security used to be fairly simple and straightforward. IT and OT networks were completely separate. IT was responsible for the IT network and OT/ICS teams were responsible for their environments.
Originally, everything was air gapped, meaning there was no connection between the IT environment and the OT environment. The physical separation between the networks acted as an effective barrier to keep everyone and everything out.
As IT started implementing digital transformation, the safeguard provided by the air gap started to dissolve. Now, air gaps are nearly a thing of the past.
Unfortunately, many OT teams don’t realize that they aren’t air gapped anymore. This means they are working with a false sense of security.
Increased integration and information sharing between the two environments has created a number of problems. The greatest challenge is incomplete network visibility.
Data is flowing continuously between different devices and systems. Without a strong foundation of visibility, it can be very difficult to get a clear and complete picture of where data is coming from and going to.

Organizations are constantly increasing the number of edge computing and IoT devices. Seemingly no industry is exempt from this evolution.
Oil and Gas companies are using IoT sensors to remotely monitor worker safety on offshore rigs, construction sites are monitoring crane loads, and railroad companies are relaying information on engine performance back to corporate headquarters.
What all of these devices have in common is that they rely on internet connectivity to transmit data. This connectivity creates multiple security loopholes and potential attack points that can endanger IT infrastructure.
While cloud computing isn’t a new idea, virtual programmable logic controllers (PLCs) are a more recent innovation.
Cloud-based data creates additional security concerns. Proper policies and protections for data storage, migration, and access have become even more important than in a traditional network.
Ensuring proper visibility standards in the cloud and in virtual PLCs is a complex, but critical process. Organizations must invest additional time and resources into managing the inherent risk associated with this innovation.
#4 - Remote Access & Remote Operations
The remote work revolution fueled by COVID has had a significant and permanent impact on organizational structure and access policies.
While most companies aren’t staying 100% remote, there is still a huge increase in the number of devices that are now remotely connected to networks. With all of that information being remotely accessible, the air gap is gone because the data has to come back to a consolidation point.
These are just a few of the key factors driving the need for increased visibility within ICS/OT environments. The future is bright for companies that get it right. There are infinite opportunities for businesses to get better, faster, and stronger through digital transformation.
Organizations that successfully implement this type of increased, secure connectivity will excel, grow, and gain a competitive advantage.
In 2021, there was a significant increase in threat groups and ransomware attacks on ICS/OT networks. Companies are under increasing pressure to improve their OT network visibility and minimize the effects of these threats, both new and old.
At Garland Technology, we’re seeing a big demand from customers deploying security solutions such as Dragos. Our network TAPs and packet brokers feed data to the tools, providing the network visibility necessary to enable effective asset and threat detection, as well as incident response.
Watch our latest roundtable webinar with Dragos where we discuss tactics and strategies for strengthening your ICS/OT visibility.
If the inline security tool goes off-line, the TAP will bypass the tool and automatically keep the link flowing. The Bypass TAP does this by sending heartbeat packets to the inline security tool. As long as the inline security tool is on-line, the heartbeat packets will be returned to the TAP, and the link traffic will continue to flow through the inline security tool.
If the heartbeat packets are not returned to the TAP (indicating that the inline security tool has gone off-line), the TAP will automatically 'bypass' the inline security tool and keep the link traffic flowing. The TAP also removes the heartbeat packets before sending the network traffic back onto the critical link.
While the TAP is in bypass mode, it continues to send heartbeat packets out to the inline security tool so that once the tool is back on-line, it will begin returning the heartbeat packets back to the TAP indicating that the tool is ready to go back to work. The TAP will then direct the network traffic back through the inline security tool along with the heartbeat packets placing the tool back inline.
Some of you may have noticed a flaw in the logic behind this solution! You say, “What if the TAP should fail because it is also in-line? Then the link will also fail!” The TAP would now be considered a point of failure. That is a good catch – but in our blog on Bypass vs. Failsafe, I explained that if a TAP were to fail or lose power, it must provide failsafe protection to the link it is attached to. So our network TAP will go into Failsafe mode keeping the link flowing.
Single point of failure: a risk to an IT network if one part of the system brings down a larger part of the entire system.
Heartbeat packet: a soft detection technology that monitors the health of inline appliances. Read the heartbeat packet blog here.
Critical link: the connection between two or more network devices or appliances that if the connection fails then the network is disrupted.