Technology6 min read

Firewalls, IDS/IPS & VPN: Your Network Perimeter Explained

How a next-gen firewall segments trust zones, how intrusion prevention works, and where VPNs fit in a modern remote-work world — including the shift toward Zero Trust.

Published July 29, 2026Updated July 29, 2026

FirewallIDSIPSVPNNGFWZero TrustZTNANetwork Security

The next-gen firewall

The firewall is the gatekeeper between your trusted network and the untrusted internet. A modern next-generation firewall (NGFW) does far more than block ports — it inspects application traffic, enforces identity-based policy, and integrates threat intelligence.

Firewall zones

Traffic is grouped into trust zones — untrusted (internet), DMZ (public-facing services), and trusted (internal LAN). Policy controls exactly what may cross between them.

IDS vs IPS

IDS (Intrusion Detection System) — watches and alerts on suspicious traffic.
IPS (Intrusion Prevention System) — blocks it inline, in real time.

NGFWs combine both with application awareness (App-ID), TLS inspection, and threat intelligence feeds.

VPN types

Type	Use case
Client VPN	Remote employees connecting to HQ resources.
Site-to-Site	Permanently linking two offices securely.

The shift to Zero Trust: VPNs are increasingly paired with (or replaced by) Zero Trust Network Access (ZTNA), which grants access to specific apps rather than the whole network. IDENETY can advise on the right approach for your environment — and ZTNA is included in the COMPLETE MSP plan.