There are 3 authentication methods that are supported by vCloud Director:
1: Local: These are the local users which are created at the time of installing vCD or creating any new organization. If you have configured vCD with default configuration, then the first local account that is created is “administrator” user who is system admin for the vCD.
2: LDAP service: A LDAP service enables the organization to use their own LDAP servers for authentication. Users can then be imported into vCD from the configured LDAP. If you have a multi-tenant based vCD deployment, then each organization can use their own LDAP service for authentication.