Wildcard certificates
Wildcard certificates secure a domain and all its subdomains using a single certificate. They are denoted by an asterisk (*) in the leftmost position of the domain name (e.g., *.example.com).
Wildcard certificates are useful for securing dynamic or evolving web environments with multiple subdomains. They eliminate the need to manage individual certificates for each subdomain, simplifying SSL/TLS certificate management.
While wildcard certificates offer convenience, they may pose security risks if the private key is compromised since it can be used to impersonate any subdomain. Additionally, wildcard certificates may not be supported in all use cases, such as for extended validation (EV) certificates.
Multi-Domain certificates (SAN Certificates)
Multi-domain certificates, also known as Subject Alternative Name (SAN) certificates, allow a single certificate to secure multiple domain names (e.g., example.com, example.net, example.org).
SAN certificates are ideal for consolidating SSL/TLS certificate management for environments with multiple domains or subdomains. They provide flexibility and cost-effectiveness by securing diverse sets of domain names with a single certificate.
SAN certificates include a Subject Alternative Name extension in the certificate signing request (CSR), listing all the domain names that the certificate should secure. Each domain name must be explicitly included in the SAN field.
Unified communications certificates (UCC)
Unified Communications Certificates (UCC) are a specific type of multi-domain certificate designed for securing communication platforms such as Microsoft Exchange Server and Office Communications Server.
UCC certificates support multiple domain names and additional attributes required for Unified Communications (UC) environments, such as Microsoft Exchange Autodiscover and SIP domain names.
UCC certificates are widely supported by mail servers, collaboration platforms, and Unified Communications as a Service (UCaaS) providers, making them suitable for securing email, VoIP, and other communication services.
Extended Validation (EV) Certificates
Extended Validation (EV) certificates provide the highest level of assurance by verifying the legal identity and operational existence of the entity behind a website. Websites using EV certificates display a green address bar in most web browsers.
EV certificates are commonly used by e-commerce websites, financial institutions, and other organizations that prioritize trust and security. They help build user confidence by prominently displaying the organization's identity in the browser.
Obtaining an EV certificate involves a rigorous verification process, including verification of legal entity documents, physical address, and operational existence. Certification Authorities (CAs) perform thorough vetting to issue EV certificates.
These advanced topics in SSL/TLS certificate management provide organizations with the flexibility, security, and scalability needed to protect their web applications and services in diverse environments. By understanding and leveraging these concepts effectively, organizations can implement robust SSL/TLS security measures tailored to their specific requirements.