Powerful LDAP client

Here is a brief introduction of the LDAP protocol, which is used extensively in large organizations:
http://quark.humbug.org.au/publications/ldap/ldap_tut.html

Before integration programs with these LDAP servers, here is a fantastic LDAP testing client named JXPlorer:
http://jxplorer.org/downloads/users.html

There are 2 significant pros by using it:
1) To test the hierarchy of the LDAP server;
2) To obtain the public pem