A public certificate is a digital certificate issued by a trusted, third-party certificate authority (CA), such as DigiCert, GlobalSign, or Let’s Encrypt.<\/p>\n\n\n\n

Key Characteristics of Public Certificates<\/strong><\/h3>\n\n\n\n

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• Globally Recognized Trust: <\/strong>Public certificates are automatically trusted by major browsers, operating systems, and external users. This is because the issuing authorities are already included in the root certificate stores of these platforms.<\/li>\n\n\n\n
• Usage: <\/strong>Public certificates are commonly employed for securing websites (via HTTPS), APIs, and other public-facing applications. They ensure external users can establish trusted connections without configuration issues.<\/li>\n\n\n\n
• Validation Levels: <\/strong>Public CAs offer different validation options, such as:\n
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  • Domain Validation (DV):<\/strong> Confirms control over a specific domain.<\/li>\n\n\n\n
  • Organization Validation (OV):<\/strong> Adds business identity verification.<\/li>\n\n\n\n
  • Extended Validation (EV):<\/strong> Provides the highest level of trust and enables visible indicators like the green address bar in browsers.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n

    Common Applications<\/strong><\/h3>\n\n\n\n

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    • Encrypting communications on public websites (e.g., online banking portals).<\/li>\n\n\n\n
    • Securing email protocols (S\/MIME, DKIM, SPF, DMARC).<\/li>\n\n\n\n
    • Ensuring data integrity in third-party integrations.<\/li>\n<\/ul>\n\n\n\n

      Public certificates are ideal when your trust model involves external entities that need immediate verification and compatibility.<\/p>\n\n\n\n

      What Is a Private Certificate?<\/strong><\/h2>\n\n\n\n

      A private certificate is issued by an organization’s internal private certificate authority (CA) or enterprise PKI system.<\/p>\n\n\n\n

      Key Characteristics of Private Certificates<\/strong><\/h3>\n\n\n\n

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      • Restricted Trust Scope: <\/strong>Unlike public certificates, private certificates are not automatically trusted by external entities. They require manual configuration to establish trust within specific environments (e.g., organizational networks).<\/li>\n\n\n\n
      • Custom Use Cases: <\/strong>These certificates are tailored for internal applications that do not need to interact with broader public networks. They are often used for secure internal communications, device authentication, and private networks.<\/li>\n\n\n\n
      • Self-Signed Certificates: <\/strong>Private certs can be self-signed, meaning the organization generates and validates them internally without a third-party CA. However, self-signed certificates require careful trust management to avoid security vulnerabilities.<\/li>\n<\/ul>\n\n\n\n

        Common Applications<\/strong><\/h3>\n\n\n\n

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        • Authenticating internal corporate systems (e.g., Active Directory services).<\/li>\n\n\n\n
        • Securing VPNs for remote access.<\/li>\n\n\n\n
        • Managing internal microservices, Kubernetes clusters, and DevOps workflows.<\/li>\n<\/ul>\n\n\n\n

          Private certificates are best suited for controlled, internal environments where trust can be explicitly established and maintained.<\/p>\n\n\n\n

          When to Use Public vs. Private Certificates<\/strong><\/h2>\n\n\n\n

          Feature<\/strong><\/td>	Public Certificate<\/strong><\/td>	Private Certificate<\/strong><\/td><\/tr>
          Issuer<\/strong><\/td>	External CA (DigiCert, Let\u2019s Encrypt, GlobalSign)<\/td>	Internal CA (Active Directory Certificate Services, OpenSSL)<\/td><\/tr>
          Trust<\/strong><\/td>	Trusted by browsers & public systems<\/td>	Trusted only within an internal network<\/td><\/tr>
          Use Case<\/strong><\/td>	Websites, SaaS, APIs, email security<\/td>	Internal authentication, VPNs, DevOps, IoT<\/td><\/tr>
          Cost<\/strong><\/td>	May require purchase, some free (Let\u2019s Encrypt)<\/td>	No CA fees but requires internal management<\/td><\/tr>
          Management Complexity<\/strong><\/td>	Automated issuance & renewal via ACME<\/td>	Requires internal CA, policies, and maintenance<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n When to Use a Public Certificate<\/strong><\/h3>\n\n\n\n Consider public certificates when the goal is to secure public-facing systems or APIs where trust from external users is critical:<\/p>\n\n\n\n \n Websites and e-commerce platforms that require HTTPS encryption.<\/li>\n\n\n\n Applications that involve external integrations needing publicly trusted certs.<\/li>\n\n\n\n Email communications to ensure global compatibility and secure delivery.<\/li>\n<\/ul>\n\n\n\n When to Use a Private Certificate<\/strong><\/h3>\n\n\n\n Private certificates shine in environments where security and control are paramount, but public exposure is unnecessary:<\/p>\n\n\n\n \n Corporate intranet applications requiring secure user authentication.<\/li>\n\n\n\n Device authentication for internal IoT, mobile, or endpoint devices.<\/li>\n\n\n\n Secure communication between internal application servers and microservices.<\/li>\n<\/ul>\n\n\n\n Risks of Using the Wrong Type of Certificate<\/strong><\/h2>\n\n\n\n Selecting the wrong type of certificate can lead to significant security and operational risks:<\/p>\n\n\n\n \n Using a Private Certificate Publicly: <\/strong>Deploying a private or self-signed certificate on a public-facing website will trigger browser security warnings. These warnings flag the site as untrustworthy, leading to poor user experience and potential financial loss.<\/li>\n\n\n\n Using a Public Certificate Internally: <\/strong>Public certificates used for internal systems may expose these systems to unnecessary risk if the certificate is leaked or misconfigured. Additionally, the reliance on external CAs can complicate internal processes.<\/li>\n<\/ul>\n\n\n\n Managing Certificate Lifecycles & Security Best Practices<\/strong><\/h2>\n\n\n\n Effective lifecycle management and adherence to security best practices are essential for minimizing risks. The following strategies can enhance your organization’s certificate management processes:<\/p>\n\n\n\n Automate Certificate Issuance & Renewal<\/strong><\/h3>\n\n\n\n \n Use protocols like ACME (Automated Certificate Management Environment) for public certificate automation. ACME streamlines the process of issuing and renewing certs, reducing human error.<\/li>\n<\/ul>\n\n\n\n Enforce Strong Encryption & Key Management<\/strong><\/h3>\n\n\n\n \n Use at least 2048-bit RSA keys or ECDSA P-256 certificates to comply with industry standards.<\/li>\n\n\n\n Regularly rotate cryptographic keys and certificates to prevent vulnerabilities.<\/li>\n\n\n\n Avoid using wildcard certificates when possible, as they present a single point of failure.<\/li>\n<\/ul>\n\n\n\n Monitor & Audit Certificate Usage<\/strong><\/h3>\n\n\n\n \n Implement systems that track certificate expiration dates to prevent disruptions.<\/li>\n\n\n\n Use tools like Certificate Transparency logs and directory insights to review certificate activity and detect unauthorized changes.<\/li>\n<\/ul>\n\n\n\n Secure Your Organization with JumpCloud<\/strong><\/h2>\n\n\n\n Navigating the complexities of public and private certificates can be daunting, but with the right tools, your organization can streamline the process and prioritize security.<\/p>\n\n\n\n JumpCloud simplifies certificate management by centralizing identity and access controls within a single platform:<\/p>\n\n\n\n \n Automate certificate policies and lifecycles.<\/li>\n\n\n\n Enforce secure authentication practices like MFA and conditional access.<\/li>\n\n\n\n Monitor and audit activity with Directory Insights.<\/li>\n<\/ul>\n\n\n\n With JumpCloud, IT teams can ensure secure, frictionless access while maintaining compliance across diverse environments.<\/p>\n\n\n\n Explore More<\/strong><\/h3>\n\n\n\n Try a guided simulation<\/a> of JumpCloud’s capabilities or contact our sales team<\/a> to see how we can support your security and certificate management needs.<\/p>\n","protected":false},"excerpt":{"rendered":" Public and private certs serve different purposes. Learn which to use, how to manage them, and security risks to avoid in enterprise environments.<\/p>\n","protected":false},"author":120,"featured_media":118269,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_oasis_is_in_workflow":0,"_oasis_original":0,"_oasis_task_priority":"","inline_featured_image":false,"footnotes":""},"categories":[23],"tags":[],"collection":[2775],"platform":[],"funnel_stage":[3016],"coauthors":[2537],"acf":[],"yoast_head":"\n