Which of the following cannot be watched by the Presence feature of UCM?
- an MGCP trunk
- an SCCP line
- a SIP line
- a SIP trunk
A Media Gateway Control Protocol (MGCP) trunk cannot be watched by the Presence feature of Cisco Unified Communications Manager (UCM). Presence enables an IP phone user to monitor other directory numbers (dns) in real time by displaying a status icon beside dns that appear in speed-dial lists or directory lists, such as the Missed Calls list, on an IP phone. The icon can represent one of the following three states:
-Unknown – The registration status of the device that is associated with the directory dn cannot be determined.
-On-hook – The device that is associated with the dn is registered and currently in the on-hook state.
-Off-hook – The device that is associated with the dn is registered and currently in the off-hook state.
Devices that can send Presence requests for information about dns are called watchers. Session Initiation Protocol (SIP) Uniform Resource Identifiers (URIs) or dns that can be monitored by Presence are known as presence entities, or presentities. Presence can send and receive presence requests and responses only on Skinny Client Control Protocol (SCCP) lines, SIP lines, and SIP trunks. If Presence requests or responses are sent to an MGCP trunk or to an H.323 trunk, those requests are rejected by UCM.