5.1.2.2 Using SSL/TLS
Active Directory supports LDAP message security on an SSL/TLS-protected connection to a DC in accordance with [RFC2246].
As indicated in the previous section, Active Directory does not permit SASL-layer message confidentiality/integrity protection mechanisms to be employed on an SSL/TLS-protected LDAP connection.
Active Directory supports channel binding on SSL/TLS-protected LDAP connections, as specified in [RFC5929], [RFC5056], and [RFC4121]. Note that for LDAP connections, a DC MUST support the tls-server-endpoint type binding, as specified in [RFC5929] and [RFC5056].
Active Directory can be configured for channel binding in the following ways:
To not use channel binding (the default).
To use channel binding but refuse connections that do not meet channel binding requirements.
To use channel binding and permit connections that do not meet channel binding requirements.
The mechanism to specify such configurations is implementation-defined.