Company X currently uses a Cisco Unified Communications Manager, which has been configured for IP desk phones and Jabber soft phones. Users report however that whenever they are out of the office, a VPN must be set up before their Jabber client can be used. The administrator for Company X has deployed a Collaboration Expressway server at the edge of the network in an attempt to remove the need for VPN when doing voice. However, devices outside cannot register. Which two additional steps are needed to complete this deployment? (Choose two.)
A. A SIP trunk has to be set up between the Expressway-C and Cisco UCM.
B. An additional interface must be enabled on the Cisco UCM and placed in the same subnet at the Expressway.
C. The customer firewall must be configured with any rule for the IP address of the external Jabber client.
D. The Expressway server needs a neighbor zone created that points to Cisco UCM.
E. Jabber cannot connect to Cisco UCM unless it is on the same network or a VPN is set up from outside.
Mobile and Remote Access Through Cisco expressway Deployment Guide
“Expressway deployments for Mobile and Remote Access do not require SIP trunk connections between Unified CM
and Expressway-C. Note that the automatically generated neighbor zones between Expressway-C and each discovered Unified CM node are not SIP trunks”.
This might be and old question and not valid anymore.
The only problem with answer D is due to the expression “Expressway sever” that is used to reference the VCS-E or the Expressway-E, since they execute the server role for the Firewall Traversal client-server technology.