In the Conference Bridge Configuration window, select Cisco IOS Enhanced Conference Bridge in the Conference Bridge Type drop-down list box. Configure the Conference Bridge Name, Description, Device Pool, Common Device Configuration, and Location settings . In the Device Security Mode field, select Encrypted Conference Bridge.C ick Save.
http://www.cisco.com/en/US/docs/voice_ip_comm/cucmbe/security/6_0_1/secugd/secuconf.html
