What is a Security Policy?
A security policy is a formal document in which an organisation sets out its goals, principles and frameworks for information security.
It forms the basis for the way people, processes and technology handle the confidentiality, integrity and
availability of information.
The security policy is the central steering instrument for protecting data, systems and infrastructure.
🧠 Purpose of a security policy
| Objective | Explanation |
|---|---|
| Provide direction | Sets the course and priorities for information security |
| Establish accountability | Who is responsible for what? (see Governance) |
| Manage risk | Connects policy to risk management and security measures |
| Comply with legislation | Such as the BIO, AVG, ISO 27001 or IEC 62443 |
| Foundation for execution | Underpins plans such as the Incident Response Plan and continuity management |
🧱 Typical components of a security policy
| Component | Description |
|---|---|
| Introduction & scope | What does the policy cover, and who does it apply to? |
| Objectives | Protection of data, systems and processes |
| Organisation & governance | Roles, functions and responsibilities (CISO, line management, etc.) |
| Risk management | Frameworks for risk assessment, mitigation and acceptance |
| Access management | Guidelines for authentication, authorisation and identity management |
| Incident handling | Reference to the Incident Response Plan |
| Logging & monitoring | Anomaly detection, logging policy, detection and forensics |
| Physical security | Access to data centres, equipment and production environments |
| Technical measures | Firewalls, encryption, patch management, hardening |
| Awareness & training | User training, codes of conduct, phishing awareness |
| Enforcement & sanctions | What happens in the event of non-compliance? |
🏭 Security policy in OT environments
Operational Technology (OT) imposes additional requirements:
| Aspect | Policy attention |
|---|---|
| Availability > confidentiality | Production or vital processes must not be brought down |
| Hardware lifecycle | Long-term support of older equipment requires a different approach |
| Network segmentation | Clear zones and firewall rules must be embedded in policy |
| Firmware patch policy | Policy for safely updating PLCs, HMIs and embedded systems |
| Physical access to installations | Field cabinets, operator panels, SCADA rooms |
The security policy must explicitly cover OT — or include a dedicated OT policy section.
🔐 Relationship to other frameworks and plans
| Framework/plan | Relationship to the security policy |
|---|---|
| BIO | Government organisations must comply with the Baseline Information Security |
| ISO 27001 | International standards framework that assumes an established security policy |
| IEC 62443 | Security standards specifically for industrial/OT systems |
| Security by Design | Policy must require secure architecture in development and procurement |
| Continuity management | Security also supports business continuity |
| Crisis communication plan | Determines how and when incidents are communicated |
✅ Best practices
- Update annually and after major incidents or reorganisations
- Ensure that policy is not only technical but also people-centred
- Have policy reviewed legally and approved at executive level
- Connect policy to measurable KPIs and controls
- Make the policy known and understandable to staff and partners
📌 In summary
The security policy is the backbone of responsible and sustainable information security.
Without clear principles, roles and guidelines, technology alone is not enough — particularly in critical IT and OT environments.