AD Certificate Services on Windows Server 2019 allows you to create a scalable, secure, and manageable infrastructure for user and resource management, and provide support for directory-enabled applications such as Microsoft Exchange Server. It can create, validate, and revoke public key certificates for internal uses of an organization. AD Certificate Services provides a distributed database to store and manage information about network resources and application-specific data from directory-enabled applications. AD Certificate Services can be used by administrators to organize elements of a network, such as users, computers, and other devices, into a hierarchical containment structure. The hierarchical containment structure includes the Active Directory forest, domains in the forest, and organizational units (OUs) in each domain.

AD Certificate Services could be used for security enhancement by binding the identity of a person, device, or service to a corresponding private key. AD CS gives you a cost-effective, efficient, and secure way to manage the distribution and use of certificates.

AD Certificate Services supports Secure/Multipurpose Internet Mail Extensions (S/MIME), secure wireless networks, virtual private network (VPN), Internet Protocol security (IPsec), Encrypting File System (EFS), smart card logon, Secure Socket Layer/Transport Layer Security (SSL/TLS), and digital signatures.