Selecting and Working with Certificate Authorities

Certificate Authorities (CAs) serve as trusted third parties in the SSL/TLS ecosystem, verifying identities and issuing certificates. The choice of CA impacts cost, issuance speed, support quality, and additional features. Major commercial CAs like DigiCert, Sectigo (formerly Comodo), and GlobalSign offer comprehensive services including validation, support, and warranty programs. Newer entrants like Let's Encrypt provide free automated certificates, democratizing encryption across the web.

Evaluating CAs requires considering multiple factors beyond price. Browser and device compatibility ensures your certificates work across your user base. Some CAs maintain better compatibility with older systems, while others focus on modern platforms. Support quality becomes critical during installation issues or security incidents. Enterprise customers often value dedicated account management and 24/7 technical support. The CA's reputation and history of security incidents should factor into decisions for high-value applications.

The application process varies significantly between CAs and certificate types. DV certificates from automated CAs like Let's Encrypt complete within minutes through automated challenges. Traditional CAs offering OV and EV certificates require account creation, documentation submission, and validation waiting periods. Understanding these timelines helps organizations plan implementations and avoid service disruptions. Many CAs offer trial certificates or short-term options for testing before committing to longer-term purchases.

Working effectively with CAs involves understanding their specific requirements and processes. Each CA maintains documentation about supported validation methods, required documentation formats, and technical specifications. Building relationships with CA support teams can expedite problem resolution and provide insights into best practices. Some CAs offer APIs for automated certificate management, enabling integration with deployment pipelines and infrastructure automation tools.