Hi Pushkar,

Without doing anything extra, your installation should have the CallManager Embedded LDAP Directory based on the users as configured in the DC Directory in CallManager.

http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/admin/4_1_3/ccmsys/a04direc.html

If you would like to integrate with your existing corporate directory such as Microsoft Active Directory, a good place to start would be the LDAP Directory chapter of the SRND.

http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/srnd/4x/42drctry.html

The actual steps to integrate the CallManager with the desired directory are described here:

http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/dir_plugin/plug413.html

Hope this helps.

Regards,

Michael.