Traditionally, legacy devices, detectors, and first-generation sensors operated in silos, or a closed loop network, disconnected from the internet. Today, our infrastructure’s traffic signals and lighting systems are rapidly evolving into connected Operational Technology (OT).
As this digital transformation continues, the security of these systems becomes mission-critical. Unlike a consumer-oriented IT breach, a malfunction or hack in a traffic signal system can immediately escalate into a public safety crisis.
While our teams don't write the security software or draft high-level policies, we spend a significant amount of time installing and maintaining the controllers, devices, and networking at the "last mile,” of a signalized intersection.
One strategy we have found effective is to treat scheduled preventative maintenance visits as opportunities to document and mitigate OT cybersecurity risks. By integrating a simple security checklist into pre-planned visits, technicians can identify critical vulnerabilities before they are exploited.
Here are our top five cybersecurity items that can be addressed as part of field maintenance:
1. Identity Management One of the simplest yet most overlooked elements of traffic signal system security. Far too many agencies rely on default PINs for controller access; while this may be convenient for technicians, it creates significant vulnerabilities and exposes the agency to unnecessary liability. To secure your systems, unique PINs must be created, used, and diligently managed.
2. Identify "Silent Sensors" Document every device in the system, specifically "silent" sensors that do not respond to standard IT pings or network scans. If a device is invisible to your IT department, it is likely unmonitored and vulnerable.
3. Audit Legacy and Un-patchable Systems Identify aging hardware that can no longer receive security updates. Often, the cost and risk of trying to secure a legacy device outweigh the cost of an upgrade. By documenting these during a preventative maintenance visit, agencies can plan for replacements in the next maintenance cycle, avoiding emergency repairs and duplicated efforts.
4. Vigilance with Identifying and Running Software Upgrades. Too often we have seen large networks of traffic signals (300+) where the same controllers are running on eight or nine different versions of software. To the untrained eye, this is not a major issue as the traffic signals themselves still function well on older and dissimilar software versions. The lack of upgrades leads to controllers that have potentially missed numerous security patch upgrades which are critical to the overall security of the signalized network.
5. Propose Network Isolation As LiDAR and other ITS technologies increase connectivity, the"blast radius" of a single compromised device grows. Technicians can suggest ways to isolate last-mile controllers to ensure that a breach at one intersection cannot spread across the entire municipal network.
Regardless the age or configuration of you traffic signal systems, it is probably time to consider ways to incorporate cybersecurity tactics into your preventative maintenance.
