LDAP, as described in [RFC4511] and [RFC4512], is an Internet protocol that is used for querying and modifying entries in a directory server. LDAP provides a general purpose directory for storing information about objects. The LDAP user schema, as described in [RFC4519], defines a set of attributes for objects contained in a directory server.
This extension defines a set of extensions to LDAP and the LDAP user schema that provides attributes and object types related to the operation of e-mail clients and servers. These attributes and object types include the following: