Differences Between LDAPv2 and LDAPv3 :
LDAPv3 supports the following implementations that were not supported in LDAPv2:
•The use of UTF-8 for all text string attributes to support extended character sets. Active Directory sends all responses in UTF-8 encoded form.
•Operational attributes that the directory maintains for its own use (for example, to log the date and time when another attribute is modified).
•Referrals, which allow a server to direct a client to another server that might have the information the client is requesting. An LDAP server can return a referral to an LDAP client when the operation presented by the client cannot be serviced locally and the LDAP server has knowledge of other LDAP servers that can handle the operation.
•Schema publishing with the directory, which allows a client to discover what object classes and attributes a server supports.
•Extended searching operations that allow paging and sorting of results and client-defined searching and sorting controls.
•Stronger security through an SASL-based authentication mechanism.
•Extended operations, which provide additional functionality without changing the protocol version.
LDAPv3 is backward compatible with LDAPv2. A requirement of an LDAPv3 server is that an
LDAPv2 client be able to connect to it.