The PKI Challenge

Designing and implementing a PKI represents one of the most critical infrastructure decisions organisations face. The complexity of modern digital ecosystems demands robust public key infrastructure that secures everything from hybrid cloud environments to IoT devices, yet many implementations fail due to inadequate planning or architectural missteps.

The reality of PKI implementation is stark: organisations rush into deployment without comprehensive planning, typically facing certificate management nightmares, security gaps, and compliance failures far more expensive than proper design would have cost.

Modern public key infrastructure must support increasingly complex requirements: hybrid cloud environments, DevOps workflows demanding automated certificate lifecycle management, millions of IoT devices requiring secure authentication, and microservices architectures where traditional security models no longer apply.

Most organisations underestimate their certificate requirements. What begins as managing hundreds of digital certificates quickly scales to thousands or millions, creating operational overhead that becomes unmanageable without proper automation and governance.

Common PKI Deployment Mistakes

Inadequate Architecture Planning The choice between two-tier PKI architecture, three-tier hierarchies, or single-tier designs fundamentally determines security posture and operational complexity. Many organisations select inappropriate CA hierarchy models that either expose the root CA's private key to unnecessary risk or create excessive operational complexity.

Insufficient Private Key Protection The most common PKI deployment mistake involves inadequate protection of CA private keys. Without proper hardware security modules and offline root CA storage, organisations expose their entire PKI to catastrophic compromise. A single breach of root CA private keys invalidates all certificates issued by that certification authority.

Certificate Lifecycle Mismanagement 70% of enterprises experience certificate-related incidents annually. Poor certificate management leads to expired certificates causing service outages, security gaps from revoked certificates still in use, and compliance failures from inadequate certificate operations documentation.

Weak Certificate Revocation Infrastructure Many implementations neglect robust certificate revocation mechanisms. Without properly configured certificate revocation lists (CRL) and Online Certificate Status Protocol (OCSP) responders, compromised certificates remain trusted, undermining the security of the entire PKI infrastructure.

Integration Failures Legacy PKI designs assumed static, on-premises environments. Today's reality demands PKI infrastructure that integrates with Active Directory Certificate Services, cloud platforms, container orchestration, and API-driven DevOps workflows. Certificate enrollment, issuance, and renewal must support modern application architectures.

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Why: How Unsung Solves PKI Challenges

At Unsung, PKI is all we do. We design and build end-to-end public key infrastructure solutions shaped around your unique business requirements, not just your infrastructure.

With deep experience across both public and private sectors, we recognise that successful PKI implementation requires addressing people, processes, and governance alongside the technology stack. We offer vendor-agnostic advice and deliver scalable, standards-based architectures using best-in-class tools.

Architecture Design That Balances Security and Operability

We help organisations navigate critical architectural decisions that impact security, operational complexity, and long-term flexibility.

CA Hierarchy Design We design appropriate PKI hierarchy structures based on your security requirements and operational capacity:

• Two-tier PKI architecture combining offline root CA with online issuing CAs, balancing security through air-gapped root certificate authorities with operational efficiency for day-to-day certificate issuance
• Three-tier architecture introducing intermediate CA layers between root and issuing certificate authorities, enabling role segregation and compartmentalisation for large enterprises
• Hybrid models combining private PKI for internal infrastructure with public certificate authorities for external-facing services requiring universal browser trust

Root CA and Issuing CA Configuration We establish certification authority hierarchies where only a root CA operates permanently offline with tamper-evident safety mechanisms, whilst issuing CAs handle day-to-day certificate operations. This separation ensures root certificates remain protected whilst maintaining operational efficiency.

PKI Infrastructure Deployment Models We assess trade-offs between private CA deployment, public certificate authorities, and managed PKI services:

• Private PKI infrastructure providing complete control over certificate policy, validation procedures, and security policies
• Public CA integration for external services requiring browser trust
• PKI-as-a-Service reducing operational overhead whilst maintaining policy customisation
• Internal PKI infrastructure secured through hardware security module protection and comprehensive access controls

Robust Private Key Protection

We implement defence-in-depth strategies protecting the private key pair at every certificate authority level.

Hardware Security Module Implementation We deploy hardware security modules providing FIPS 140-2 Level 3 tamper-resistant storage for CA private keys. These dedicated cryptographic appliances ensure CA certificate private keys never exist in plaintext outside secure hardware boundaries, with tamper-evident safety mechanisms destroying key material if physical intrusion is detected.

Offline Root CA Security We establish offline root certificate authorities with air-gapped systems, strict physical access controls, and multi-person authorisation. The root CA activates only for signing intermediate CA certificates or certificate revocation lists, minimising exposure whilst maintaining the certification path integrity for the entire PKI.

Key Management Procedures We develop comprehensive key management protocols covering:

• Key ceremony procedures for root CA private key generation
• Private key protection throughout the certificate lifecycle
• Key escrow and recovery for business continuity
• Role separation ensuring no single administrator compromises certificate operations

Complete Certificate Lifecycle Management

We design and implement automated certificate management spanning the complete certificate lifecycle from request through revocation.

Certificate Enrollment Automation We implement appropriate certificate enrollment mechanisms for diverse environments:

• Autoenrollment through Active Directory for Windows domain environments
• SCEP (Simple Certificate Enrollment Protocol) for network devices
• ACME protocol support for cloud-native applications
• RESTful APIs for microservices and container platforms
• Manual processes for certificate requestors requiring human validation

Certificate Issuance and Distribution We establish certificate issuance workflows using certificate templates that enforce security policies whilst enabling operational efficiency. Certificate templates define key usage restrictions, certificate validity periods, and subject name formats, ensuring the right certificate authority issues certificates with appropriate security characteristics.

Certificate Renewal and Expiration Management We implement monitoring and automation preventing the service outages that occur when certificates expire. Layered alerting, automated renewal workflows, and certificate discovery across hybrid environments ensure certificate holders maintain current, valid certificates without manual intervention.

Certificate Distribution Infrastructure We configure Authority Information Access (AIA) and CRL distribution points ensuring certificate validation functions across network boundaries. Load-balanced, highly available infrastructure supports certificate chain validation from any location.

Comprehensive Certificate Revocation Infrastructure

We implement robust mechanisms ensuring revoked certificates cannot be used for unauthorised purposes.

Certificate Revocation List Management We configure CRL publication with appropriate frequency balancing security and operational efficiency. Delta CRLs reduce bandwidth whilst providing incremental updates of the latest revoked certificates between full CRL publications.

Online Certificate Status Protocol Deployment We deploy OCSP responders providing real-time certificate revocation checking with sub-100ms response times. OCSP stapling configuration on web servers improves SSL/TLS handshake performance whilst eliminating client-side validation delays.

Validation Infrastructure Optimisation We size and optimise certificate revocation infrastructure handling peak validation loads, typically 10-20 times steady-state volumes, with caching strategies maintaining performance without compromising security.

Security Policy and Governance Framework

We develop comprehensive documentation establishing operational procedures and security controls for your certification authority infrastructure.

Certificate Policy Development We create certificate policies defining certificate usage standards, naming conventions, validation requirements, and trust levels. The certificate policy establishes which certificate authorities can issue certificates for specific purposes and what identity verification certificate requestors must complete.

Certification Practice Statement We document operational procedures implementing certificate policy requirements in your specific environment. The certificate practice statement details certificate lifecycle procedures, key management practices, physical security controls, and incident response procedures.

Certificate Requirements Analysis We work with stakeholders to define certificate requirements across:

• User certificates for email encryption, authentication, and digital signatures
• Server certificates for SSL/TLS and application authentication
• Device certificates for IoT and network infrastructure
• Code signing certificates for application and firmware integrity

Certificate Holder Identity Verification We establish appropriate identity verification procedures aligned with certificate types and intended uses, from domain validation through extended validation for public certificates, to Active Directory integration for internal certificate operations.

Compliance and Standards Alignment

We ensure PKI infrastructure meets regulatory requirements and industry standards.

Regulatory Compliance We design PKI infrastructure satisfying stringent compliance frameworks:

• FIPS 140-2 Level 3 for government agencies
• PCI DSS for financial services
• HIPAA for healthcare organisations
• eIDAS for European entities

Standards-Based Architecture We implement PKI infrastructure following industry best practices:

• RFC standards for certificate formats and protocols
• CAB Forum baseline requirements where applicable
• Vendor security guidelines for certificate authorities
• Industry-specific security policies

Audit Preparation We develop documentation and evidence collection supporting compliance audits. Continuous compliance monitoring through automated tools tracks configuration compliance, access controls, and operational procedures.

Why Organisations Choose Unsung

PKI Specialists PKI is our sole focus. Our engineers maintain deep expertise across certificate authorities, hardware security modules, certificate management platforms, and PKI integration, bringing proven experience from complex deployments across industries.

Vendor-Agnostic Guidance We select technologies based on your specific certificate requirements, not vendor relationships. Our experience spans commercial platforms, open-source solutions, and hybrid approaches combining multiple technologies.

Business-Focused Design We design public key infrastructure solving business problems, not just implementing technology. Our approach addresses compliance requirements, operational constraints, and business objectives alongside technical architecture.

End-to-End Delivery From initial certificate requirements analysis through operational handover, we deliver complete PKI implementation services. Organisations receive functioning certificate authority infrastructure with documented procedures, trained staff, and ongoing support options.

Future-Ready Architecture We design PKI infrastructure accommodating evolution, including algorithm migration to post-quantum cryptography, integration with emerging technologies, and scaling to support growth across certificate holders and use cases.

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The Unsung Approach

Requirements Definition

We collaborate with stakeholders defining business, compliance, and technical certificate requirements. This analysis catalogues certificate holders across users, devices, and applications whilst anticipating future growth in certificate operations.

Architecture and Solution Design

We create vendor-agnostic PKI hierarchy designs aligned with best practices. Architecture decisions encompass CA certificate trust models, certificate validity periods, certificate policy frameworks, and integration with existing security infrastructure.

Security Policy Framework

We develop comprehensive certificate policy and certification practice statement documentation providing operational and legal foundation for your certification authority operations.

Platform Integration and Implementation

We deploy and configure complete PKI infrastructure integrated with your existing security and identity systems.

Certificate Authority Setup We implement certificate authorities using appropriate platforms:

• Windows Server Active Directory Certificate Services for Microsoft environments
• Linux-based certificate services for open-source deployments
• Cloud-hosted certificate authorities for hybrid architectures
• Hardware security module integration at all certificate authority tiers

Active Directory Integration We configure seamless integration with Active Directory Certificate Services, leveraging existing domain infrastructure for automated certificate enrollment whilst maintaining security through centralised certificate templates and Group Policy enforcement.

Certificate Store Management We establish appropriate certificate stores across user systems, servers, and devices, ensuring certificate distribution, certificate chain validation, and automated certificate renewal function correctly.

Application and Service Integration We integrate PKI infrastructure with applications requiring digital certificates:

• Web servers and load balancers for SSL/TLS
• VPN concentrators and network access control
• Email systems for S/MIME encryption and digital signatures
• Code signing workflows for software integrity
• IoT device authentication frameworks

Deployment Strategy and Migration

We implement carefully orchestrated rollout phases validating functionality before organisation-wide deployment.

Pilot Deployment We establish limited-scope pilots with representative use cases validating core PKI functionality. Pilot testing encompasses diverse certificate types: user authentication, web server certificates, and device certificates across your environment.

Root Certificate Distribution We deploy root certificates establishing trust in your certification authority across all client systems. Distribution leverages Group Policy for domain-joined systems, mobile device management for mobile devices, and documented manual procedures for systems outside centralised management.

Legacy System Integration We develop integration strategies for applications lacking modern certificate enrollment support, including manual certificate installation procedures, format conversions, and intermediate certificate chain modifications where required.

Certificate Operations Handover We transfer operational responsibility to your teams with comprehensive knowledge transfer, training on certificate management platforms, and documented procedures for routine certificate operations.

Monitoring and Operational Excellence

We establish monitoring and management capabilities preventing certificate-related incidents.

Certificate Discovery and Inventory We implement automated discovery identifying certificates across on-premises infrastructure, public cloud services, and edge locations. Most organisations underestimate certificate counts by 50-80% without automated discovery, creating blind spots in certificate lifecycle management.

Expiration Monitoring We configure layered alerting at appropriate intervals before certificate expires, escalating through management channels whilst triggering automated renewal where appropriate.

Security Auditing We establish logging and monitoring of all certificate operations enabling compliance reporting and security investigation. Regular access reviews verify only authorised personnel retain administrative access to certificate authorities.

Performance Optimisation We tune infrastructure supporting high-volume certificate issuance, addressing common bottlenecks in certificate authority processing capacity, network bandwidth for certificate distribution, and validation infrastructure sizing.

Governance and Documentation

We create operational documentation supporting secure PKI infrastructure management, including runbooks for certificate operations, incident response procedures, and compliance reporting frameworks.

Knowledge Transfer

We upskill internal teams through targeted training on certificate lifecycle management, certificate authority administration, troubleshooting certificate issuance issues, and maintaining security controls.

Technical Capabilities

Certificate Authority Technologies

• Windows Server 2019/2022 Certificate Services
• Linux-based open-source certificate authorities
• Cloud-native certificate authority services
• Hardware security module integration from leading providers

Certificate Management Platforms We work with all major certificate management platforms and can recommend the most appropriate solution for your specific requirements. Our vendor-agnostic approach ensures technology selection is driven by your business needs rather than commercial relationships.

Enrollment Protocols

• Autoenrollment via Group Policy
• SCEP (Simple Certificate Enrollment Protocol)
• ACME (Automatic Certificate Management Environment)
• EST (Enrollment over Secure Transport)
• RESTful APIs for modern applications

Validation Infrastructure

• Certificate Revocation List (CRL) services
• Delta CRL optimisation
• Online Certificate Status Protocol (OCSP) responders
• OCSP stapling configuration
• Certificate chain validation optimisation

Building Digital Trust Infrastructure

Successful PKI implementation establishes the foundation of digital trust for your organisation. The architectural decisions made during initial design impact security, operations, and business capabilities for years.

Unsung ensures your public key infrastructure serves as an enabler for secure communications, identity assurance, digital signatures, and operational excellence now and in the future.

Ready to discuss your PKI requirements? Contact our team to explore how Unsung can deliver certificate authority infrastructure tailored to your organisation's needs.

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