In an era where national security depends on secure digital communications, identity assurance, and trusted data exchange, Public Key Infrastructure has become mission-critical to Defence operations. At Unsung, we deliver PKI solutions that enable Defence organisations to operate securely across all domains — from tactical edge deployments to strategic command and control systems.

Securing the Defence Digital Backbone

Modern Defence relies on interconnected networks, classified systems, and coalition partnerships that demand the highest levels of cryptographic assurance. PKI provides the foundation for:

Strong Authentication and Identity Assurance — Certificate-based authentication ensures only authorised personnel and systems access classified networks and sensitive intelligence. From smart card logon to machine-to-machine authentication, PKI enables zero-trust architectures across complex Defence environments.

Secure Communications — Whether encrypting communications between headquarters and deployed units, or protecting data in transit across coalition networks, PKI ensures confidentiality and integrity at every layer — from email and messaging to VPN and tactical radio systems.

Code Signing and Software Integrity — Defence systems require absolute assurance that software, firmware, and configuration files have not been tampered with. PKI enables cryptographic signing of mission-critical applications and updates, protecting against supply chain attacks and unauthorised modifications. Signing keys should be protected within hardware security modules to prevent compromise.

Device and IoT Security — From unmanned systems and sensor networks to weapon platforms and shipboard systems, Defence IoT demands scalable, automated certificate lifecycle management to secure device identity and communications at scale. For a deeper look at how digital certificates underpin device trust, see our explainer.

Addressing Defence-Specific Challenges

Defence PKI operates in uniquely demanding conditions. Unsung’s expertise is shaped by our work at the highest levels of UK Defence, where we understand the challenges of:

Multi-domain operations across air-gapped, coalition, and cloud environments.

High assurance requirements including government-grade root CAs and hardware security modules.

Complex governance spanning Defence policy, NATO interoperability, and regulatory compliance.

Operational continuity with zero tolerance for downtime or certificate outages.

Cryptographic agility to respond to evolving threats including post-quantum cryptography. For a practical breakdown of what crypto agility actually involves, see our detailed guide.

Our approach combines deep technical capability with an understanding of Defence governance, operational tempo, and mission assurance requirements.

Defence organisations face an acute exposure to the harvest now, decrypt later threat. Classified information and intelligence may retain its sensitivity for decades, meaning data intercepted today could be decrypted once quantum computing matures. A CBOM is the essential first step in identifying which systems and data flows carry the greatest exposure, enabling Defence organisations to prioritise quantum-resistant protections where they matter most.

Our Defence PKI Capabilities

Strategic PKI Architecture — We design scalable, resilient PKI architectures for Defence networks operating at all classification levels. Our PKI design and build service accounts for airgap requirements, cross-domain solutions, disaster recovery, and long-term cryptographic lifecycle planning.

Root CA Design and Governance — Unsung provides end-to-end Root CA services including Certificate Policy and Certificate Practice Statement development, key ceremony facilitation, and HSM-backed key management aligned with government assurance frameworks. Our PKI consultancy team brings proven experience from classified environments.

PKI Managed Services — We operate PKI environments on behalf of Defence organisations, providing 24/7 monitoring, incident response, certificate lifecycle management, and continuous compliance support — all delivered by SC and DV-cleared personnel. Learn more about our PKI management and hosting service.

PKI Health Checks and Assurance Reviews — Our forensic PKI health checks evaluate the security posture, governance maturity, and operational health of existing certificate infrastructures, delivering evidence-based remediation roadmaps and investment cases.

Cryptographic Modernisation — As Defence prepares for post-quantum threats and embraces cloud transformation, we provide strategic guidance on crypto-agility, algorithm migration, and integration with next-generation platforms. The NIST PQC roadmap sets the key milestones against which Defence modernisation programmes should plan. Our CBOM service provides the cryptographic visibility needed to scope these programmes accurately.

Preparing for Post-Quantum Cryptography in Defence

The G7 Cyber Expert Group’s 2035 target provides a benchmark, but Defence organisations handling classified material face even more pressing timelines. NCSC guidance makes clear that planning must begin now, and the NIST roadmap sets deprecation of RSA and ECC by 2030.

Unsung supports Defence clients in building cryptographic inventories, testing quantum-resistant algorithms through platforms like Crypto4A QxHSM and QxEmulator, and developing phased migration plans that maintain operational continuity throughout the transition. For organisations with legacy IT that cannot be easily upgraded, we design architectural wrappers that bridge the gap.

Why Unsung for Defence PKI?

Unsung is a trusted PKI partner to the UK Ministry of Defence, with a proven track record of delivering high-assurance cryptographic solutions in the most demanding environments. Our team operates across all classification levels, combining technical precision with an understanding of Defence operations, policy, and mission outcomes.

Vendor-neutral expertise ensuring PKI solutions are aligned to Defence requirements, not vendor roadmaps.

Sustained performance including 100% SLA achievement and zero security incidents across multi-year managed service engagements.

Agile delivery using solution accelerators and collaborative working methods to meet compressed timelines without compromising assurance.

Continuous innovation through automation, lifecycle integration, and early adoption of emerging standards.

Whether designing a new Root CA for a classified cloud platform, conducting a forensic health check of legacy infrastructure, or operating PKI at scale across Defence networks, Unsung brings the depth of expertise and operational discipline that national security demands.

Clients We Have Worked With

We are proud to work with clients including the UK Ministry of Defence and Babcock, delivering PKI solutions that underpin secure Defence operations.

Our Recent Projects

Solution Design and Delivery for Defence Private Cloud Platform — Root CA design, governance documentation, and key ceremony execution for a new highly assured cloud environment.

Enterprise PKI Health Check for Defence Organisation — Comprehensive assessment of PKI platform health, governance processes, and operational maturity following service transition.