BE
The deployment of a Unified CM Session Management Edition enables commonly used applications, such as conferencing or videoconferencing to connect directly to the session management cluster, which reduces the overhead of managing multiple trunks to leaf systems. Unified CM Session Management Edition supports the following applications: Unity, Unity Connection
Meeting Place, Meeting Place Express
SIP and H.323-based video conferencing systems
Third Party voice mail systems
Fax servers
Cisco Unified Mobility
The following applications must connect to the leaf cluster: Unified Contact Centre, CUCM, Unified Contact Centre Express
Cisco Unified Presence Server
Attendant Console
Manager Assistant
IP IVR
Cisco Voice Portal
References: http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/session_mgmt/deploy/8_5_1/overview.html