Quick Answer
Dividing your network into separate zones so a compromise in one doesn't reach the others. On a flat network, ransomware on a receptionist's laptop can reach your servers. Segmented, it can't.
What Gets Separated
Typical zones:
Employee devices — laptops and desktops for day-to-day work
Servers — applications, databases, file storage
Guest Wi-Fi — visitors, with no route to internal systems
IoT devices — cameras, printers, smart devices, door entry systems
Production or specialist equipment — manufacturing systems, medical devices, anything running software you can't update
Traffic between zones is controlled by firewalls, VLANs, or access rules, so each segment gets only the connectivity it needs.
Where to Start
Full segmentation is a network redesign, which is why it gets postponed indefinitely. Three things deliver most of the benefit for much less work:
Guest Wi-Fi first. Easiest to separate, and it removes a route in from anyone in your car park.
Then cameras, printers, and IoT. These devices rarely receive security updates and often ship with default credentials. They need internet access, not access to your file server.
Then anything unpatchable. Equipment running old Windows versions the vendor won't let you update. If you can't secure the device, control what can reach it.
Why It's Worth the Effort
Attackers rarely stop at the first machine. They move sideways looking for administrators, servers, and backups. Segmentation is what makes that hard, and it's one of the few controls that limits damage after a compromise rather than trying to prevent one.
Example Scenario
A 180-person manufacturer ran office computers, production equipment, security cameras, and guest Wi-Fi on one network. An assessment found a compromised employee laptop could reach production systems. PureStack separated office, manufacturing, guest, and server traffic into controlled segments behind firewall policies.
How PureStack Segments Your Network
We map what can currently reach what, separate the high-risk zones first, and implement it in stages so the business keeps running while the network changes underneath it.