How to Build a Secure Network for Factories
Discover how to secure your factory network with practical steps: segmentation, layered protection, and OT device hardening. A simple guide to boost cybersecurity without disrupting operations!
📖 Estimated Reading Time: 3 minutes
Content
Factories today aren’t the isolated, air-gapped fortresses they used to be. Factory cybersecurity has become a top priority as manufacturing networks evolve. With IoT (Internet of Things) and OT (Operational Technology) connecting everything from sensors to machines, the opportunities are endless—but so are the risks. The old idea of "trusted" and "untrusted" zones doesn’t cut it anymore. And let’s be real: zero-trust security sounds great until a shopfloor worker with gloves and safety glasses is locked out of a critical system.
So how do you build a secure network without making everyone’s life harder? Cybersecurity in manufacturing doesn’t have to be complicated—it just needs the right approach. Let’s break it down into some simple, effective steps. Bonus: you don’t need a PhD in cybersecurity to pull this off (although it might help with the jargon).
Step 1: Segment Your Network (Zones FTW)
First things first, divide and conquer. Cybersecurity shopfloor strategies often start with segmentation. Split your network into zones based on what’s happening in each area. This way, if something goes wrong in one zone, it doesn’t bring the whole factory down.
Common Zones You Might Need
Production Floor Zone: This is where the magic happens. Think PLCs, HMIs, and CNC machines. Keep these devices away from less secure parts of the network.
Corporate Zone: Office computers, email servers, and the place where everyone sends "Reply All" by mistake. This zone often connects to the internet but shouldn’t touch your OT devices.
Storage and Logging Zone: If machines push logs or operational data to a server, stick them in their own zone.
Guest Zone: For contractors, maintenance teams, or the person who asks for Wi-Fi the moment they walk in.
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Quick Example
Got machines that need to upload logs to a storage server? Set up a small fenced-off zone just for that. Use a firewall to make sure those machines talk only to the server and nothing else. Simple, right?
Step 2: Add Layers of Protection
Layers aren’t just for cake — they’re essential for network security too. A secure factory network relies on multiple layers of protection to stop threats at every stage. A single firewall is a good start, but two firewalls? Now you’re talking.
Outer Firewall: Your First Line of Defense
This firewall sits at the edge of your network, protecting against internet-based threats. What it should do:
Block bad traffic from the internet.
Handle VPN connections for remote access.
Act as a basic intrusion detector.
Inner Firewall: The Core Protector
An inner firewall adds another layer, protecting your critical servers and systems.
Why two firewalls? Using different vendors for the outer and inner layers reduces the risk of a vulnerability taking down both (like having two-factor authentication for your network).
Real-Life Setup
Set up an outer firewall for internet-facing protection.
Use an internal firewall to control access between zones.
Step 3: Secure OT Devices
OT devices are often the weak link in factory networks. Cybersecurity factory initiatives must address vulnerabilities in OT devices to prevent exploitation. They weren’t exactly designed with hackers in mind, and many still run ancient software that thinks "security" is a buzzword.
Common OT Devices and Risks
PLCs and HMIs: These are your control systems, and they’re usually running outdated software.
Sensors and IoT Devices: Great for data, bad for security if they’re using unsecured protocols.
CNC Machines and Robots: High-value targets with low security.
Tips for Hardening OT Devices
Patch Regularly: Keep firmware and software up to date. Yes, it’s boring, but so is getting hacked.
Control Access: Only allow trusted users to change settings. Think "No Admin for You!"
Filter Protocols: Use firewalls to block unnecessary communication.
Monitor Everything: Enable logging so you can spot weird activity early.
OT devices need love too, even if they’re still rocking their Windows XP playlists…
Step 4: Build Resilience
Downtime in a factory is expensive. The last thing you need is a single failure taking out your whole network. Here’s how to keep things running:
Redundancy: Set up backup firewalls and network paths. Don’t let one failure ruin your day.
Monitoring: Use tools to watch for threats in real-time. Be proactive, not reactive.
Incident Response: Have a plan for when things go sideways. The faster you act, the less damage is done.
Wrapping Up
Securing a factory network is a critical aspect of modern manufacturing. By following key principles like network segmentation, layered protection, and OT device hardening, you can create a resilient, secure factory network that minimizes risks without disrupting operations. The goal isn’t to overcomplicate but to create a strategy that is both effective and manageable.
Remember, cybersecurity isn’t just a one-time project; it’s an ongoing process. Regular updates, monitoring, and adjustments ensure that your defenses remain strong as technology evolves. With the right plan in place, you can confidently protect your factory’s operations and stay ahead of potential threats.
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