Certificate Templates and Enrollment
CAs integrated with Active Directory, called Enterprise CAs, issue many different types of
certificates, based on built-in certificate templates. Enrollment can be automatic, manual
with automatic issuance, or manual and approved by a CA Administrator. Permissions set on
the templates further determine which groups of Windows users and computers can actually
obtain a certificate. Windows Server 2003 introduced version 2 certificate templates, which
can be customized and add features such as auto enrollment and even key archival. Key
archival allows the private key associated with the certificate to be stored in a central
database. This is important for recovery. Encrypted files, for example, cannot be decrypted
without the private key associated with the public key used to protect the file encryption key.
By archiving the EFS private keys, an organization ensures the availability of the data, even if
the original keys are destroyed or damaged.
Windows Server 2008 R2 introduced version 3 templates, which add support for the
newer Microsoft Crypto-API, giving administrators the ability to produce certificates using
the more advanced and secure elliptic curve cryptography (ECC) cryptography service
providers (CSPs).