Nominet: The role of protective DNS in securing an open and resilient digital future

# Overview In this talk, representatives from Nominet Cyber discuss the critical role of Protective DNS (PDNS) in securing public infrastructure and building a resilient digital future. Based in Oxford in the UK, Nominet Cyber has a team of approximately 70 people and operates Protective DNS services on behalf of the National Cyber Security Centre (NCSC) in the UK and the Australian Cyber Security Centre (ACSC). The service is designed to mitigate online disruptions for public sector bodies, enabling innovation and growth across the digital economy.

# Key Topics - **Protective DNS (PDNS) Operation and Reach**: Nominet delivers PDNS across the vast majority of the UK public sector, ranging from central and local government to healthcare and emergency services. The service aims to protect organizations from the majority of cyber threats online, aligning with the ethos of the Active Cyber Defence program. - **Threat Intelligence and Decision-Making**: The service relies on threat intelligence to determine what domain activity should or should not be blocked, separating malicious traffic from benign requests to prevent attacks such as phishing. - **Customer Experience and Awareness**: Operating the service involves supporting customer interactions across the lifetime of use—from onboarding on day one onward—alongside raising awareness through webinars, communications, and industry events such as CyberUK. - **Cybersecurity Mindset and Public-Private Collaboration**: Building collective resilience requires embedding cybersecurity best practices and online safety into education and professional training early on, as well as fostering non-profit-driven collaboration between the public and private sectors.

# Technical Details - **Architecture and Scale**: The PDNS platform operates at national scale, capable of protecting entire governments or nations by intercepting and mitigating cyber threats at the DNS level. - **Threat Mitigation**: The team conducts threat research and leverages threat intelligence to detect and mitigate malicious activity—such as phishing campaigns and cyberattacks—blocking threats before they disrupt critical citizen-facing operations. - **Operational Structure**: The team is split into two primary operational areas: customer onboarding and lifetime relationship management for public sector entities, and threat intelligence research that informs real-time blocking and filtering rules.

# Takeaways - **Quiet and Effective Protection**: PDNS functions with minimal fuss and disruption, providing verifiable evidence of blocked malicious threats across critical infrastructure like healthcare and emergency response. - **Need for Greater Public Benefit Initiatives**: Speakers highlighted the need for expanded government intervention under active cyber defence programs and encouraged public and private sector entities to collaborate beyond pure profit motivations to build collective resilience. - **Foundational Education**: Embedding online safety into foundational education and professional training ensures individuals maintain a security-oriented mindset both at work and in their personal lives.