/mcpC H A P T E R 27 Intercom • Intercom Overview, on page 311 • Intercom Prerequisites, on page 312 • Intercom Configuration Task Flow, on page 312 • Intercom Interactions, on page 316 • Intercom Restrictions, on page 317 • Intercom Troubleshooting, on page 318 Intercom Overview Intercom is a type of phone line that combines the functionality of a traditional line and a speed dial. With an intercom line, a user can call the intercom line of another user, which answers automatically to one-way audio whisper. The recipient can then acknowledge the whispered call and initiate a two-way intercom call. You can use an intercom line to dial any other intercom line in the intercom partition, or you can preconfigure the line to target an intercom line outside the intercom partition. Intercom allows a user to place a call to a predefined target. The called destination answers the call automatically in speakerphone mode with mute activated. This sets up a one-way voice path between the initiator and the destination, so the initiator can deliver a short message, regardless of whether the called party is busy or idle. To ensure that the voice of the called party does not get sent back to the caller when the intercom call is automatically answered, Unified Communications Manager implements whisper intercom. Whisper intercom ensures that only one-way audio exists from the caller to the called party. The called party must manually press a key to talk to the caller. An auto-answer tone indicates the beginning of the whisper intercom state for both the sender and the recipient. Intercom and Default Devices Each intercom line needs a default device. The intercom line is displayed only on the designated default device. When the administrator assigns an intercom line to a device, the system sets the device as the default device for the intercom line if not set previously. The administrator can modify the default device for the intercom line. When the administrator changes the default device to a different device, the intercom line gets removed from the original device, even though the intercom line may still be assigned to the original device. Feature Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs 311