Network Access Control has a reputation for complexity that has caused many organizations to delay or abandon deployment. This guide cuts through the complexity and provides a practical roadmap for getting NAC working in your environment.
Understanding the Basics
At its core, NAC answers three questions about every device connecting to your network: Who is this device? Does it meet our security requirements? What network resources should it have access to? Everything else — the technical architecture, the enforcement mechanisms, the remediation workflows — is in service of answering these three questions.
The Three Phases of NAC Deployment
- Discovery: Deploy in monitor-only mode to learn what’s on your network. This phase typically reveals surprises — unknown devices, unexpected connections, policy violations that have been occurring undetected.
- Enforcement: Enable enforcement for your highest-confidence, lowest-impact policies first — typically guest segmentation and minimum antivirus requirements.
- Optimization: Add more sophisticated policies, tighten enforcement, and integrate with other security systems like SIEM and patch management.
Common Pitfalls to Avoid
Don’t try to enforce everything at once. Don’t skip the discovery phase. Don’t underestimate the need for exception management — there will always be devices that legitimately can’t meet every policy requirement. Plan for these before you go live with enforcement.