VPNs vs. Ephemeral Tunnels in Long-Life Assets
When it comes to securing remote access for long-lived infrastructure like cyber-physical systems (CPS), operational technology (OT), and Internet of Things (IoT) devices, many organizations still rely on Virtual Private Networks (VPNs). But VPNs weren’t built for the reality of modern distributed systems that need to run safely for decades.
In fact, static VPNs can be downright dangerous in these environments. Ephemeral, process-bound tunnels are the best solution to minimize the risk posed by VPNs accessing CPS/IoT/OT devices. When we say “ephemeral,” we simply mean “short-lived”.
Photo by Rubidium Beach on Unsplash
The Problem with VPNs
Always-on Connections: A VPN creates a sustained connection to a termination point, even when idle.
Detectable Attack Surface: Hackers can wiretap and "fingerprint" traffic, so every termination point becomes a target for future decryption with Harvest Now, Decrypt Later (HNDL) schemes.
User Friction: Users often have to manually start sessions or switch VPN profiles, slowing workflows.
Data Exposure Risk: Commonly regarded as a safety measure, "break and inspect" practices (easy to do on a VPN), actually expose unencrypted data to third-party VPN providers and disloyal employees.
Not Scalable: Imagine millions of IoT devices or thousands of OT controllers tied to always-on VPNs and it’s easy to see that the attack surface balloons exponentially.
Why CPS, OT, and IoT Are Hit Hardest
OT (Operational Technology): Industrial control systems (ICS/SCADA) often run 24/7. A persistent VPN connection to each system becomes a permanent open door for attackers to try.
IoT: From sensors to EV chargers, billions of small, distributed endpoints realistically can’t run secure, always-on VPN connections. Each one would represent a potentially vulnerable entry point.
CPS: Integrated digital + physical systems, like EV charging networks or wind farms, face long asset lifecycles. A VPN session that lives for decades is effectively a decades-long invitation to attackers.
Case in Point: CCTV and IoT Devices
CCTV cameras and audiovisual (AV) systems are some of the most widely deployed IoT devices in the world, protecting everything from airports to hospitals to military bases. Ironically, the very systems meant to provide security often end up as attack vectors themselves.
Traditionally, CCTV systems require open inbound ports or VPN connections for maintenance, updates, and feed access, but those open connections can be hijacked. Attackers have used them for surveillance and espionage, as well as a stepping stone into larger networks.
In one case study [LINK], Xiid SealedTunnel™ secured CCTV infrastructure by:
Closing all inbound ports, making cameras invisible to attackers.
Enabling maintenance and updates through outbound-only, process-bound tunnels.
Wrapping all video traffic in triple-layer, quantum-secure encryption.
Preserving performance on even degraded or “dirty” networks.
The result: CCTV and AV devices remained accessible to authorized users while being completely inaccessible to attackers.
This same principle applies to every long-lived IoT or OT asset: VPNs create standing risks, while ephemeral tunnels remove them.
Ephemeral, Process-Bound Tunnels: A Better Fit
Xiid SealedTunnel™ takes the opposite approach:
On-Demand Only: Tunnels spin up only when a workload or device needs to communicate.
Ephemeral by Design: If idle, they expire in minutes or even seconds, leaving nothing for attackers to find.
Invisible Infrastructure: No public IPs, no inbound ports, no VPN servers to target.
Frictionless Experience: Users don’t need to stop and “fire up a VPN.” Connections are seamless, workload-bound, and automatic.
The Security and Usability Advantage
For OT teams: Process-bound tunnels eliminate persistent open connections to controllers, reducing the chance of remote compromise.
For IoT providers: Ephemeral tunnels prevent billions of distributed devices from becoming billions of attack surfaces.
For CPS operators: Long-lived infrastructure is matched with short-lived, invisible tunnels that scale security across decades without leaving static exposure.
Conclusion
CPS, IoT, and OT systems are built to last decades. VPNs are built to stay “always on.” The two simply don’t mix. With Xiid SealedTunnel™, tunnels exist only when needed and vanish when not, giving operators the seamless access they want, and attackers nothing to exploit.
