BIO2-Compliant Public Cloud for the Dutch Public Sector

This article is also available in Dutch.

As of 2025, implementation of the updated BIO2 (Baseline Information Security for the Dutch Government, version 2) will become a statutory requirement for many Dutch public sector organizations. This includes entities seeking to modernize their IT landscape through public cloud adoption—without compromising on security posture or compliance with regulatory frameworks.

BIO2 introduces approximately 200 tactical-level government-specific controls. These high-level controls must first be translated into operational security measures prior to implementation. This step is often cited as a key implementation challenge for government entities.

This blog presents a 10-step roadmap with best practices for effective BIO2 implementation in public cloud environments, based on real-world experience with AWS migrations in the Dutch public sector. The approach is cloud-agnostic and also applicable to platforms such as Microsoft Azure and Google Cloud Platform.

What is BIO?

Since 2020, the BIO has served as the standardized information security baseline for all levels of Dutch government. It offers a unified control framework to safeguard information systems against cyber threats and vulnerabilities. Built upon ISO 27001/27002, the BIO extends these standards with controls tailored specifically to public sector requirements.

The upcoming version—BIO2—has been designed to reduce implementation complexity. Its structure aligns with ISO 27002:2022. Certain controls derived from sector-specific legislative sources have been removed. BIO2 is currently in development. A draft version including its legal basis, obligations, and control sets is available via the GitHub repository of the Dutch Ministry of the Interior and Kingdom Relations (BZK).

Why is BIO2 Compliance Critical—and Who Must Comply?

BIO compliance is essential for ensuring the confidentiality, integrity, and availability of public sector information and the continuity of critical government services. Under the new Dutch cybersecurity legislation (Cyberbeveiligingswet, Cbw), BIO2 compliance will become legally binding for central government agencies, provinces, municipalities and likely for independent administrative governmental bodies (ZBOs). Supervision and enforcement fall under the authority of the Digital Infrastructure Inspectorate (RDI).

Further information on BIO2, NIS2, and the Dutch cybersecurity legislation can be found at Dutch Digital Government website

BIO2 Implementation in Public Cloud: A 10-Step Framework

1. Establish Control Scope Based on Risk Assessment
   BIO2 is a risk-based framework, not a prescriptive checklist. Conduct a Risk Self-Assessment (RSA) to identify primary risks and determine which BIO2 controls are required to mitigate them.
2. Define Information Security Requirements
   Conduct a structured assessment of confidentiality, integrity, availability, and continuity (RTO/RPO) requirements for cloud-based workloads. Although not explicitly included in BIO2, incorporating relevant legal and regulatory requirements (e.g., GDPR, sectoral guidelines) is strongly recommended.
3. Establish Control Scope Based on Risk Assessment
   BIO2 is a risk-based framework, not a prescriptive checklist. Conduct a Risk Self-Assessment (RSA) to identify primary risks and determine which BIO2 controls are required to mitigate them.
4. Define Public Cloud Security Principles
   Establish architectural principles such as least privilege, zero trust, defense-in-depth, secure-by-design, and automation-first. These principles form the foundation for a secure and scalable public cloud architecture.
5. Design Security Governance Model and Roles
   Implement a cloud security operating model aligned with the shared responsibility model. In public cloud environments, CSPs (Cloud Service Providers) are responsible for physical BIO2 controls, while CSCs (Cloud Service Consumers)—such as government organizations—remain responsible for securing their devices, data and identities. DevOps teams typically act as first-line control owners, leveraging centrally defined security guardrails to ensure compliance. These guardrails are embedded within the Cloud Landing Zone (see step 5).
6. Establish a Secure Cloud Foundation: the Cloud Landing Zone
   A well-architected Cloud Landing Zone typically addresses ~80% of technical BIO2 controls and provides a reusable security baseline. Key components include:

   1. Federated Identity & Access Management> via integration with enterprise identity providers (e.g., Microsoft Entra ID).

   2. Centralized Logging & Monitoring for real-time detection and incident response.

   3. Network Security Controls including segmentation, firewalls, and secure hybrid connectivity.

   4. Security Guardrails, such as:

      1. Service Control Policies (restrict cloud usage to approved services)

      2. Data residency and encryption enforcement

      3. Resource and data classification (CIA labelling)

      4. Backup & disaster recovery across cloud regions

   5. Integration with External Security Platforms, e.g., SIEM, XDR, NDR.
      Document the Cloud Landing Zone architecture in a High-Level Design (HLD), which serves as authoritative evidence for internal and external audits.
   6. Implement Application-Specific Security Controls
      Layer additional controls on top of the baseline as required by the application context. For example, enable DDoS mitigation or Web Application Firewalls (WAFs) for internet-facing services. Leverage CSP-native security services where feasible. Enforce policies through automated infrastructure-as-code deployments.
   7. Control Mapping and Documentation
      Maintain a control register that maps selected BIO2 controls (see step 2) to their implementation. Reference the Cloud Landing Zone HLD and assign control ownership according to the operating model. Use assurance reports (e.g., SOC 2 Type II) to validate CSP-managed controls, and verify applicability across services and cloud regions.
   8. Independent Security Validation
      Conduct periodic validation of control effectiveness through third-party penetration tests, red team exercises, vulnerability scans, and formal audits. This is essential for evidencing control effectiveness, as required under BIO2 and the Dutch cybersecurity legislation (Cyberbeveiligingswet, Cbw).
   9. Continuous Monitoring and Compliance Automation
      Implement continuous compliance monitoring using CSP-native tools (e.g., AWS Config, Azure Policy) or third-party platforms. Non-compliance must trigger immediate remediation—ideally by the DevOps team responsible for the relevant workload.
   10.  Maintain Risk and Control Registers
       Practice ongoing risk management in alignment with ISO 27001. Maintain an up-to-date risk register and control register for cloud workloads. Capture new risks and findings (e.g., from security audits or pentests) and incorporate them into backlog items for responsible control owners.

Conclusion

Implementing BIO2 in public cloud environments within the Dutch government context demands a structured, risk-driven approach. A robust Cloud Landing Zone and automated security guardrails provide efficient coverage for the majority of technical BIO2 controls. Clear governance, defined ownership, and continuous validation mechanisms enable demonstrable compliance with BIO2.

By combining modern public cloud capabilities with a compliant and secure architecture, public sector organizations can accelerate innovation without compromising security or regulatory alignment.