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Firewall
Definition
A firewall is a security system that monitors and filters incoming and outgoing network traffic based on predefined rules. It forms a barrier between a trusted internal network and untrusted external traffic.
Firewalls come in two forms: hardware firewalls (separate equipment, such as a next-generation firewall) and software firewalls. Next-Generation Firewalls (NGFW) go beyond traditional firewalls by inspecting packet contents, recognizing applications, and integrating with threat intelligence. The evolution of firewalls reflects the changing threat landscape. Cloud-native firewalls protect workloads in public cloud environments. Web Application Firewalls (WAF) specifically protect web applications against attacks such as SQL injection and cross-site scripting. A firewall alone provides insufficient protection: a layered security architecture with EDR, SIEM and network segmentation is essential.
Impact on organisations
The impact on organisations is substantial. Under NIS2, organisations in critical sectors are required to implement appropriate technical and organisational measures. DORA sets comparable requirements for financial institutions. The average cost of a security incident amounts to millions of euros in recovery, legal fees and reputational damage. National cybersecurity centres warn that advanced threat actors increasingly target European organisations.
Protection
Effective protection requires a layered approach combining technical measures with organisational processes and awareness. Regular testing of security measures through pentests and security assessments is essential. An incident response plan with clear roles and communication lines prepares the organisation for worst-case scenarios. Continuous monitoring through an MDR service or internal SOC detects threats before they can cause damage. Security awareness training ensures employees recognise and report suspicious activities.
The threat landscape evolves rapidly. Organisations that operate only reactively face increasing risk. A proactive security strategy combines technical measures with regular security testing, continuous monitoring and a practised incident response team. NIS2 requires organisations in critical sectors to implement demonstrable security measures, including supply chain risk management and regular assessments. The cost of prevention is a fraction of the cost of a security incident: the IBM Cost of Data Breach Report 2024 documents average costs of $4.88 million per incident. Organisations with an MDR service or practised incident response team save an average of $2.66 million per incident compared to organisations without preparation.
How DEFION helps
DEFION offers a comprehensive portfolio of security services that help organisations address this threat. The 24/7 SOC team continuously monitors for suspicious activities. Pentests and red teaming exercises test the effectiveness of existing security measures. In the event of an incident, the DFIR team is immediately available for forensic investigation and recovery. This requires a proactive security strategy that is regularly tested and updated based on the current threat landscape. Organisations that invest in prevention and preparation save significantly on incident response costs. ISO 27001 provides a proven framework for structurally organising information security.