NSA’s New Zero Trust Playbook: Why the ‘Discovery Phase’ is Your New Best Friend
The NSA just dropped the ultimate cheat sheet for Zero Trust, and it’s not just for the military.
Access NSA-level security without the need for a Pentagon-sized budget. On January 14, 2026, the National Security Agency (NSA) released its first Zero Trust Implementation Guidelines (ZIGs). While these documents are designed for the Department of Defense, the 'Discovery Phase' guide offers a practical framework that SMB leaders can use to strengthen network security.
The main takeaway is simple: you can’t protect what you can’t see.
Before purchasing new security tools, complete a thorough inventory of your assets and map your data flows. Start with simple, cost-effective solutions like spreadsheets or free, open-source asset trackers. Reputable options include Snipe-IT, GLPI, OCS Inventory, and NetBox, which allow SMBs to begin inventory and mapping without additional costs.
The Primer Focuses on Strategy, Not Just Tools
The Zero Trust Implementation Guideline Primer encourages SMBs to adopt a strategic mindset. Zero Trust is a strategy, not a product. Adopting this approach can significantly reduce risk, as breaches often cost SMBs an average of $200,000 and may cause severe financial distress. Focusing on strategy over technology spend helps businesses better mitigate threats.
The NSA recommends an "Assume Breach" approach. This means building defenses with the expectation that an attacker may already be inside the network. For SMBs, this shifts the focus from perimeter defenses to stronger internal segmentation and monitoring.
To apply this principle, use a three-step workflow: detect, isolate, and restore. Assign clear roles to support execution. The owner should ensure resources are available, approve budgets and policy changes, and communicate priorities to stakeholders. When choosing an MSP, prioritize those with Zero Trust experience and proven responsiveness, as these are essential for effective monitoring and threat isolation. The MSP should monitor network activity, detect suspicious behavior, and isolate threats by segmenting affected areas. Staff should restore operations by following recovery protocols, initiating backups, and reporting issues to the MSP. If your MSP lacks Zero Trust expertise or is unresponsive, provide additional training or consider a temporary consultant. This approach helps leaders embed security into daily operations and build resilience.
This primer connects high-level theory, such as NIST standards, with practical implementation. It warns that applying advanced restrictions without a clear strategy can disrupt business processes before improving security.
For instance, a midsize retail business rushed to install sophisticated security layers without first mapping its data flows. This oversight led to unexpected system outages and client service disruptions, illustrating the importance of disciplined and strategic sequencing.
The “Discovery Phase”: An Often Missed Step
The second document, the Discovery Phase Guideline, is especially helpful for SMB leaders. It tackles the most common cybersecurity problem: not having enough visibility.
The NSA says this phase is about creating a “reliable baseline.” You need to know exactly what’s on your network before you can decide who or what to trust.
The main parts of the Discovery Phase are:
Comprehensive Inventory: List every user and device on your network. For each device, write down its identity, who owns it, and what it’s used for.
Data Flow Mapping: Learn how important data moves through your system. Find out where customer data is stored, who can access it, and where it goes next.ns.
Baselining Access: Write down what “normal” behavior looks like. You can only spot problems if you know what’s normal.
Practical Next Steps for SMB Leaders
You do not need a large budget to apply these principles. Use the NSA's framework to guide your actions over the next 30 days instead of waiting for the next quarterly review. Allocate minimal resources to make this plan manageable:
30-Day Action Plan:
- Time: Approximately 5-10 hours per week should be sufficient for most SMBs to complete the tasks.
- Staff: Ideally, one or two team members with a basic understanding of cybersecurity will be adequate to manage the process.
- Tools: Use spreadsheets or free, open-source asset tracking software for inventory, and lean on simple data visualization tools for mapping data flows.
Week 1: Make a Complete Inventory
Start by listing all your hardware and software. Write down what each item does, who owns it, and why it’s there.
Start by listing all your hardware and software. Write down what each item does, who owns it, and why it’s there.
Week 2: Conduct a Trust Audit
Examine areas of implicit trust within your network. Review Trust in Your Network. Are they trusted solely because they are inside the building or on the VPN, and reassess these assumptions.
Week 3: MSP Check and Data Flow Mapping
Give the Discovery Phase PDF to your MSP or IT lead and ask them to check your setup against the NSA’s visibility standards. At the same time, map out how important data moves through your system and note key access points and destinations.
Week 4: Set Baselines and Report
Figure out what normal behavior looks like and set up ways to spot anything unusual. Write a report on what you find and where you can improve.
This step-by-step plan helps you take action right away, turning good intentions into real results.
Take a look at the original documents. They may be technical, but you can use them in parts. Share the Discovery Phase PDF with your MSP or IT lead and ask for a review of your setup based on the NSA’s visibility standards.
The “Discovery Phase” might seem routine, but it’s the foundation of a strong, resilient business.
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