What Is PKI as a Service (PKIaaS)?

Managing public key infrastructure (PKI) involves more than issuing digital certificates. Organizations must also manage renewals, revocations, key security and the infrastructure that supports these processes. PKI-as-a-Service (PKIaaS) shifts much of that operational burden to a managed cloud service.

PKIaaS is a managed, cloud-based solution providing PKI functionalities that eliminate the need for on-premises infrastructure. PKIaaS makes robust security accessible to all organizations, even those without extensive IT departments.

In this article, we’ll define what PKIaaS is, how it works, its core components and the benefits it offers. We’ll also explore the process of migrating from on-premises to managed PKI.

What Is PKI as a Service (PKIaaS)?

PKI-as-a-Service (PKIaaS) is a cloud service providing full public key infrastructure (PKI) functionality without on-premises infrastructure. This service, also known as managed PKI, simplifies your PKI by automating key generation and certificate management within a secure cloud-based platform.

“Cloud PKI services exist because PKI is just really hard to do in a safe, secure way. There are hundreds of pages of documentation showing how you might set up a legacy PKI like Active Directory Certificate Services in an insecure way just by using the default settings. There are tons of vulnerabilities that can happen if you don’t set it up right.”

Micah Spady, Director of Product Marketing at SecureW2

With PKIaaS, organizations get the security and compliance of a full PKI framework, combined with the cost-efficiency and simplicity of the cloud. That means continuous trust architecture, cryptographic security, and identity verification, all with the cost-efficiency and simplicity of a managed service.

How PKIaaS Works: Core Components

What’s included with PKIaaS? Here are the primary components:

Cloud Hosting

PKIaaS leverages cloud infrastructure to host the PKI, eliminating the need for physical hardware and ensuring high availability, redundancy and disaster recovery. Cloud infrastructure also optimizes resources and facilitates rapid scaling.

Key and Certificate Automation

Automation in PKIaaS covers digital trust processes including key generation, digital certificate issuance, renewal and revocation.

Automating these processes drastically reduces the risk of human error and enforces real-time policy updates, while maintaining the integrity and security of digital signatures and encrypted communications.

Security Protocols and Public Key Cryptography

Robust security protocols are foundational to PKIaaS. By leveraging public key (asymmetric) cryptography, the service uses paired keys to ensure secure data encryption and seamless key exchange.

• Public key: The public key is openly distributed. It transforms plain text into an encrypted format; no one can decipher it without the matching private key. That’s why the public accessibility of this key isn’t a risk.
• Private key: The private key is closely guarded and never shared. It’s the only way to decrypt data encrypted by the public key. The security of the entire system hinges on keeping the private key confidential.

Public and private keys work together to maintain data integrity and confidentiality. When encrypted using a public key, only the corresponding private key can decrypt data. This keeps data and digital signatures secure and intact during transmission.

Managed Services

PKIaaS offers managed services, including setup, ongoing maintenance and support. These services ensure private keys, digital certificates and cryptographic algorithms are properly configured and maintained, providing end-to-end encryption and secure communications.

Why Organizations Are Moving to PKIaaS From On-Premises PKI

Running PKI in-house can work well, but it becomes harder to manage as certificate volumes, devices and workloads grow.

63% of organizations outsource some PKI functions to managed service providers, highlighting the growing demand for simpler PKI management.

2026 Ponemon study

Organizations are moving to PKIaaS for a few practical reasons:

• Less infrastructure to manage: Organizations don’t have to build, maintain, patch and monitor all the infrastructure needed to run PKI themselves.
• More automation: PKIaaS can automate certificate issuance, renewal and revocation, reducing manual work and the risk of expired certificates.
• Easier to scale: As organizations add more users, devices, applications and workloads, PKIaaS can scale without requiring the same level of infrastructure and resources.
• Access to PKI expertise: PKI requires specialized skills to operate securely. A managed provider can take care of much of this complexity.
• Better certificate visibility: PKIaaS gives security teams a more centralized view of certificates and their lifecycle across environments.
• Lower operational overhead: Teams can spend less time maintaining PKI infrastructure and more time on broader security and IT priorities.
• Greater crypto agility: Enables organizations to adopt new cryptographic algorithms and adapt to evolving security requirements without rebuilding their PKI infrastructure.

These benefits show up at every scale. A data and AI platform company moved 17,000 devices from pre-shared keys to certificate-based authentication with no on-premises PKI or RADIUS. Integrations with Okta and Jamf automate enrollment and revocation, including for the 20+ new devices the company onboards each week.

The same approach works for lean teams. A regional accounting and consulting firm with a one-person IT team, which had never built its own PKI, used the SecureW2 managed cloud PKI to replace pre-shared key Wi-Fi with certificate-based authentication.

Moving to Cloud RADIUS also let the company retire a server that cost over $800 a month, and the IT director handled the rollout alongside existing duties.

Organizations aren’t simply “going cloud”: PKIaaS doesn’t mean abandoning on-premises PKI.

Many organizations are adopting a hybrid approach, keeping sensitive PKI components in-house while using managed services for automation, scalability, and certificate lifecycle management.

The Role of the Certificate Authority (CA) in PKIaaS

In a PKIaaS model, the certificate authority (CA) acts as the central trust engine. While the cloud provider manages the physical infrastructure, the CA remains responsible for issuing trust, verifying identities and managing digital keys.

Key functions of the CA in PKIaaS include:

• Trust anchoring: Establishes and maintains the cryptographic chain of trust (Root and Intermediate CAs) to validate devices, users and applications.
• Automated lifecycle management: Issues, renews and revokes X.509 certificates automatically via protocols like ACME, SCEP or EST to eliminate manual overhead and outages.
• Root key security: Leverages cloud-hosted Hardware Security Modules (HSMs) to protect private root keys behind strict compliance standards (FIPS 140-2/3).
• Policy and governance: Enforces corporate certificate policies and maintains tamper-proof audit logs for standards like SOC 2 and ISO 27001.

What happens behind the scenes when a system needs to verify a certificate? Watch the video below for a closer look at the process and the mechanisms that help systems determine which certificates to trust.

How Certificate Lifecycle Management (CLM) Works in PKIaaS

PKIaaS manages the entire certificate lifecycle, from issuance to revocation. This includes systems and processes such as:

• Certificate authorities: PKI certificate management includes selecting trusted certificate authorities (CAs), which are organizations that serve as the official governing administrator of digital certificates.
• Certificate issuance: PKIaaS manages issuance, enlisting CAs to sign and deliver the certificates that manage access to networks and resources.
• Certificate renewal: PKIaaS also handles automated certificate renewal, preventing accidental expired certificates and maintaining secure connections.
• Certificate revocation: PKIaaS checks the issuing CA’s certificate revocation list (CRL) to deny access or invalidate previously active certificates. Automated revocation instantly invalidates compromised or expired certificates, ensuring continuous security compliance.

Watch the video below for a practical walkthrough of how PKI management brings certificate lifecycle automation, revocation and access control together.

What Are the 4 Pillars of PKI?

PKI rests on four pillars that together secure digital communication and identity.

The first is authentication, which verifies that users, devices, and servers are who they claim to be. The second is confidentiality, using encryption to keep data private in transit and at rest. The third is integrity, ensuring information isn’t altered or tampered with along the way. And the fourth is non-repudiation, which uses digital signatures to prove an action or message genuinely came from its source.

Backed by digital certificates and a trusted certificate authority, these pillars make PKI the foundation of passwordless, certificate-based security.

Authentication and Authorization in PKIaaS

PKIaaS provides robust authentication and authorization mechanisms. It uses certificates to verify user and device identities, granting appropriate access based on predefined security policies. PKIaaS providers use modern protocols for seamless, reliable verification and access controls.

PKIaaS vs. AAA (Authentication, Authorization, Accounting)

PKI is not an Authentication, Authorization, Accounting (AAA) protocol.

The AAA framework is a network access control (NAC) protocol for transmitting sensitive data, particularly over wireless networks. AAA servers help routers securely authenticate (verify user credentials), authorize (allow access), and account (record user/access details) all attempts to access the network.

Watch the video below for a quick rundown of AAA servers.

Traditional and cloud-based PKIs provide authentication for certificate requests by verifying the identity of users and devices. They also authorize access once authenticated.

But traditional PKIs don’t provide built-in accounting — a critical security measure.

Many managed PKI service providers, including the SecureW2 JoinNow Platform, include accounting for improved security, compliance and audit management.

PKI vs. Other Services

PKI is sometimes confused with other similar or related services. We’ll clear up the confusion with a few explanations.

PKIaaS vs. SSL

PKI and SSL both relate to certificate lifecycle management (CLM), but in different ways.

PKI provides the infrastructure to enable CLM, such as certificate authorities (CA) and registration authorities (RA). It contains everything an organization needs to issue, store, renew, revoke and otherwise manage digital certificates.

Secure Sockets Layer (SSL) is one component of CLM. This protocol creates an encrypted link between a web server and a browser, ensuring that all data, including digital certificates, remains private and secure.

Today, most organizations use a modernized form of encryption called Transport Layer Security (TLS), though “SSL” is still the common industry term for both protocols.

So, while PKI supports the performance of certificate lifecycle automation and management, SSL is a specific way to verify certificates within the larger CLM process.

PKI vs. IAM

PKI and IAM both manage access, but at different structural levels.

PKI is a specific type of infrastructure implemented to secure data and communications through digital certificate encryption with both private and public keys (hence, Public Key Infrastructure). PKI employs various authentication methods and authorization methods to reduce unauthorized access.

IAM, or Identity and Access Management, is a broader framework for organizational security. It involves specific policies and tools dictating which networks, resources, and data a specific user or device can access.

Secure PKI may be one tool used in a larger IAM strategy.

PKI vs. API

PKI is a system relying on both public and private keys (asymmetric cryptography) to encrypt data using digital certificates.

API stands for Application Programming Interface, a method of connecting distinct software systems for seamless operation without revealing protected information about either tool.

PKI systems may use APIs to integrate with existing infrastructure, allowing simpler adoption and smoother deployment compared to replacing existing tools.

How PKIaaS Differs From On-Premises PKI

PKI-as-a-Service offers several distinct advantages over traditional on-premises PKI, primarily through its cloud-based architecture and managed service model.

PKIaaS differentiates itself from private PKI in these ways:

Attribute	On-Premises PKI	PKI-as-a-Service
Infrastructure Management	Requires on-prem hardware installations, ongoing maintenance, and self-managed software updates	No on-prem hardware or maintenance; provider handles software updates
Scalability	Limited by your physical infrastructure	Extensible and flexible to fluctuating demands and growth
Deployment Speed	Slow: weeks to several months	Rapid: pre-configured cloud environments launch in hours
Certificate Outage Prevention	Renewal tracking is time-consuming and complex, risking outages	Automated renewal and revocation provide simple, reliable outage prevention
Automation and Integration	Limited automations, custom scripting, and Application Programming Interface (API) compatibility	Ample automations and API support offer smooth customization and integration
Security and Compliance	Dependent on staff expertise, risking security breaches, compliance issues, and poor disaster recovery response	Security and compliance experts are part of your managed services, improving compliance with regulatory requirements, protection from data breaches, and disaster recovery assistance
Cost Structure	Significant initial investment (hardware, software, installation, training) and ongoing costs (maintenance, re-education)	Subscription-based pricing spreads costs over time, eliminating the need for large capital investments
Management Complexity	Requires specialized expertise, constant oversight, and regular maintenance, increasing costs and complexity	PKI service provider handles management, maintenance, security, and compliance for more visibility with less complexity

Managing PKI in-house involves more than maintaining infrastructure. It also requires specialized expertise, careful key protection and secure certificate management.

Watch the video below to learn why organizations are turning to managed PKI and how it addresses some of the challenges of traditional PKI.

Why Certificate Lifecycle Automation Is Becoming a Core PKIaaS Requirement in 2026

In 2025, the CA/Browser Forum approved a plan to dramatically shorten the lifespan of publicly trusted TLS certificates. The table below summarizes the schedule mandated:

EFFECTIVE DATE	MAXIMUM CERTIFICATE VALIDITY
March 15, 2026	200 days from 398 days
March 15, 2027	100 days
March 15, 2029	47 days

As certificate lifespans shrink, organizations must renew and replace certificates much more frequently. Managing that process manually becomes increasingly difficult, especially across large environments.

PKIaaS addresses this challenge by automating the entire certificate lifecycle, from issuance and deployment to renewal and revocation.

Using protocols such as Automated Certificate Management Environment (ACME), PKIaaS platforms can automatically renew certificates before they expire, reducing administrative overhead and minimizing the risk of outages caused by expired certificates.

Integration with identity providers, MDM platforms and security policies further ensures that certificates remain compliant and up to date across the environment.

PKIaaS also helps organizations prepare for the future. As the industry begins adopting post-quantum cryptography standards, organizations will need infrastructure that can support new cryptographic algorithms without requiring a complete rebuild of their PKI environment.

Crypto-agile PKIaaS platforms make this transition significantly easier by allowing organizations to adapt to evolving security requirements over time.

Today, PKIaaS is about more than keeping up with shorter certificate lifecycles. It provides a scalable, automated and future-ready certificate management strategy that supports both current compliance requirements and the next generation of cryptographic security.

Common Challenges With PKIaaS

Managed PKI services aren’t a magic solution to every problem. Be mindful of these risks and disadvantages:

• Incompatibility with legacy PKI infrastructure management practices: Moving from traditional PKI to PKI-as-a-Service isn’t just a system change — it’s a process change, too. Many enterprises and smaller organizations alike require operational updates, which can extend implementation.
• Unclear responsibility: Along with procedural changes, implementing PKIaaS also requires a review of governance policies and ownership among teams. Who owns intra- and inter-departmental approvals? How will you enforce new policies? Who will enforce them? Don’t just define ownership — document it.
• Automation without customization: PKIaaS platforms offer certificate automations that reduce manual work, minimize human errors, improve efficiency and meet or exceed compliance requirements. However, you still need to personalize details like certificate lifetimes, trust policies, key sizes and revocation practices to match company and industry standards.

In addition to your in-house PKI experts, lean on your PKIaaS provider to help streamline implementation, maximize personalization and guide essential policy and governance updates.

When to Use PKI-as-a-Service

A managed PKIaaS solution may be right for your organization if you manage:

• Distributed workforces: Across multiple facilities and remote teams, many organizations trust managed PKI services for secure network access.
• High volumes of digital certificates: Managed PKI is perfect for organizations with an extensive number of certificates, which can require significant oversight.
• Rapid certificate issuance needs: For teams needing to issue certificates on demand, PKIaaS can streamline the process without compromising compliance.
• Myriad Internet of Things (IoT) devices: With hundreds, thousands or even millions of IoT devices comes a need for individual device validation. At this scale, manual device management isn’t realistic, but PKI-as-a-Service can provide certificate security for IoT devices.
• Teams without sufficient PKI experts: Without an appropriate number of specialized, highly trained staff members, you won’t have the resources to handle the complexities of traditional PKI in-house.
• Low-budget infrastructure: Traditional PKIs require expensive hardware and infrastructure: on-premises data centers, hardware security modules (HSMs) to store and manage keys, load balancers, maintenance staff and more. PKIaaS solutions typically offer lower costs.

If you have plenty of PKI experts and just a few certificates, you can probably handle traditional PKI.

But for reliable, efficient, secure, and scalable PKI infrastructure, without the in-house headaches, PKI-as-a-Service is the ideal choice.

The Role of PQC in PKIaaS

Post-Quantum Cryptography (PQC) prepares Public Key Infrastructure as a Service for the quantum era, replacing vulnerable algorithms like RSA and ECC with quantum-resistant standards (such as ML-KEM and ML-DSA).

In a PKIaaS environment, PQC plays three critical roles:

• Enabling crypto agility: PKIaaS platforms allow organizations to seamlessly upgrade root/intermediate CAs and re-issue quantum-safe certificates across millions of endpoints without tearing down physical infrastructure.
• Mitigating “Harvest Now, Decrypt Later” risks: Protects sensitive data captured today from being decrypted once quantum computers become powerful enough to break classic public key encryption.
• Hybrid certificate issuance: Facilitates the deployment of dual-signature (hybrid) X.509 certificates—combining traditional algorithms with PQC—so systems stay compliant with legacy standards while achieving quantum readiness.

How to Migrate From Legacy PKI to PKIaaS

Migrating to PKIaaS requires careful planning to ensure a smooth transition without interrupting critical services. The migration process follows five key phases:

• Phase 1: Discover & assess: Map out all existing CAs, certificate profiles and expiration dates, and document all manual processes across participating teams.
• Phase 2: Identify & test use cases: Test the new PKI platform in parallel with legacy systems using low-risk scenarios to validate configurations without disrupting operations.
• Phase 3: Phased rollout: Issue new certificates via the PKIaaS platform while allowing existing legacy certificates to gradually expire and renew on the new system.
• Phase 4: Maintain & automate: Increase automation and continuous monitoring to streamline management while leveraging the provider’s expert support for ongoing oversight.
• Phase 5: Decommission legacy infrastructure: Shut down legacy PKI servers once all active certificates have migrated, lowering operational costs and reducing your attack surface.

For more details on PKIaaS implementation, check out this article: Running PKI-as-a-Service.

Core Capabilities to Look for in a PKIaaS Solution

If you’re narrowing this down to the five genuinely non-negotiable qualities for a cloud PKIaaS provider, prioritize the following:

1. Strong private key protection: Private keys must be securely protected, ideally with HSM-backed security, strict access controls and clear ownership of key material.
2. End-to-end certificate lifecycle automation: The platform should automate certificate issuance, renewal, rotation and revocation. Manual certificate management defeats a major reason for moving to PKIaaS.
3. High availability and reliability: PKI supports critical authentication and security systems, so the service needs strong uptime, redundancy, backup and disaster recovery capabilities.
4. Seamless integration: The PKIaaS platform must integrate with the organization’s existing identity providers, MDM/UEM tools, Wi-Fi infrastructure, applications, cloud environments and other security systems.
5. Visibility, control and auditability: Security teams need centralized visibility into certificates and keys, granular administrative controls, detailed audit logs and reporting for compliance and incident investigation.

What to Avoid When Evaluating PKIaaS Providers

Not every PKIaaS platform delivers the same level of security, flexibility, or long-term value. Watch for these during evaluation:

1. Using shared/multi-tenant infrastructure: Inadequate tenant isolation can expose sensitive PKI components and increase security risks.
2. Overlooking your existing stack: Integration gaps can lead to custom workarounds and additional administrative effort.
3. Ignoring future requirements: Limited support for shorter certificate lifetimes or post-quantum cryptography can create migration challenges later.
4. Underestimating audit needs: Inadequate logging can make compliance reporting and certificate investigations difficult.
5. Forgetting the migration process: A poorly planned migration can cause deployment delays, configuration issues, and unnecessary disruption.

Managed PKI-as-a-Service From SecureW2

Transitioning from traditional on-premises PKI to a managed PKI solution can drastically enhance your organization’s security posture.

The SecureW2 JoinNow Platform is a comprehensive managed PKI-as-a-Service solution linked with our cloud-based RADIUS. It seamlessly integrates with your existing infrastructure for simple deployment with robust security capabilities.

The image below provides an overview of how the platform works.

Our managed PKIaaS solutions combine simplicity, security and scalability to:

• Automate digital certificate issuance
• Strengthen authentication and authorization
• Protect sensitive data
• Enhance secure communications with advanced public key encryption
• Improve user experience
• Streamline certificate management
• Eliminate on-premises hardware
• Reduce operational costs

With features like automatic key generation, digital signatures, 802.1X authentication, and certificate authority functions, our PKI solutions are tailored to meet the demands of modern digital environments.

SecureW2 protects against adversary-in-the-middle attacks and unauthorized access, creating a highly secure and efficient public key infrastructure that protects your networks, users, devices and data.

Ready to upgrade your security infrastructure? Our managed PKI solution can transform your organization’s approach to security, simplify management and save costs. Request a free demo today.

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Frequently Asked Questions

What is the PKI for DSC?

PKI for DSC (Digital Signing Certificate) is a certificate-based framework that proves a signer's identity and confirms a document hasn't been altered after signing. The signer's private key encrypts a hash of the document; any recipient can use the corresponding public key to verify both the signature and document integrity. DSCs carry legal weight under the ESIGN Act and UETA in the US and eIDAS in the EU. PKI-as-a-Service makes DSC issuance practical at scale: organizations can issue, manage, and revoke signing certificates through a cloud CA without standing up or maintaining on-premises infrastructure.

How does PKI work?

PKI works by using two cryptographic keys: a public key and a private key. The public key encrypts data or verifies digital signatures, while the private key decrypts data or creates digital signatures. This allows secure communication between trusted parties without ever transmitting sensitive credentials, such as passwords, over the network. Public keys are bound to a user, device, or application by certificates issued by a trusted certificate authority (CA). When a connection is initiated, both parties present and validate their certificates to confirm their identities.

What is the purpose of PKI?

The purpose of PKI is to establish trusted digital identities and secure communications across networks, devices, applications, and users. PKI uses digital certificates and cryptographic key pairs to verify identities and encrypt sensitive data. Organizations commonly use PKI to enable secure Wi-Fi authentication, VPN access, HTTPS encryption, email security, device authentication, and passwordless access. Using PKI replaces vulnerable password-based authentication with certificate-based trust, reducing the risk of phishing, credential theft, and unauthorized access.

What are the two types of certificate authorities?

The two types of certificate authorities are the root CA and the intermediate CA. The root CA sits at the top of the trust chain. It's self-signed, kept offline to protect its private key, and has a lifespan of roughly 25 years. Its trust is embedded directly in operating system and browser trust stores. The intermediate CA, sometimes called an Issuing CA, operates below the root and issues end-entity certificates on its behalf. If an intermediate CA is compromised, it can be revoked without invalidating the root. This hierarchy is the backbone of how PKIaaS providers structure certificate issuance.

What are the three types of certificates?

The three core certificate types issued within a PKI are TLS/SSL certificates, code signing certificates, and client certificates. TLS/SSL certificates authenticate a server's identity and encrypt traffic between a browser and server. Code signing certificates verify a software publisher's identity and confirm that code hasn't been modified between build and distribution. Client certificates authenticate end users and devices — rather than passwords — to servers and network resources. In a PKI-as-a-service model, all three types are issued from the same managed CA hierarchy, giving organizations centralized visibility and control over every certificate across their environment.

What is an example of a PKI?

A common example is the digital certificate system that secures websites. When you visit an HTTPS site, PKI issues and validates the SSL/TLS certificate that encrypts your connection. Enterprises also use PKI to authenticate devices and users onto Wi-Fi, VPNs and applications.

Why do I need a PKI certificate?

A PKI certificate proves your identity without a password, so it can't be phished, stolen or reused. It encrypts your connections and grants secure access to Wi-Fi, VPNs, and apps, delivering stronger security and a smoother experience than credentials alone.

How do I get my PKI certificate?

Certificates are issued by a certificate authority, typically through your organization's PKI. With a managed platform like SecureW2, enrollment is automated: a self-service gateway configures your device and provisions the certificate in minutes. No manual setup or IT tickets required.