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Network Zones for Detection

Group parts of your network into zones so Access Gate can alert when traffic crosses a boundary it should not.

2 min read · Last updated 2026-04-22

Zones are a lightweight way to say "these systems belong together" and "these systems should never talk to each other". Once defined, Access Gate scores every flow against your zones and raises an alert when a boundary is crossed unexpectedly.

Configure zones

To configure different zones, head to Settings -> Subnets, and click on the pencil for a specific subnet. In the Type section, you can select a value from the dropdown presented.

ZoneTypical membersTalks to
VPNDistance access over VPNInternet, dmz
ITOffice workstations, file serversInternet, dmz, OT (proxied)
OTPLCs, HMIs, SCADA serversProxied via Access Gate
GuestGuest wifi, temporary accessIsolated — no east-west
VendorTemporary access to specific machinesIsolated — no east-west
PublicWAN exposed assetsInternet

You do not need to get zoning perfect on day one. Start with three or four zones, let traffic populate, and refine.

How Zones Power Detection

Once a flow is observed, Access Gate labels both endpoints with their zone and answers two questions:

  1. Is this crossing a boundary? If both endpoints sit in the same zone, no boundary is crossed.
  2. Is this crossing expected? You define a small matrix of allowed pairs; anything outside is flagged.

This turns zones into a cheap form of anomaly detection that does not require rule-writing.