Specifications

3-15
Cisco IOS Telephony Service, Version 2.02
Chapter 3 Additional Configuration Tasks
Information About Additional Configuration Tasks
Configuring Intercom
The Cisco IOS Telephony Service supports intercom functionality for one-way and press-to-answer
voice connections. This functionality is implemented using specially configured (from CLI or web only)
speed-dial buttons that allow a call to be placed to the selected directory number (DN) and to make the
called DN automatically answer the call in speakerphone mode, with mute activated. An alerting beep
is played to the recipient as soon as the call is auto-answered, which provides a one-way voice path from
the initiator to the recipient. To respond to the intercom call and open two-way voice, the recipient
presses the Mute button to deactivate the mute (or in the case of a Cisco IP Phone 7910, lifts the
handset).
The intercom configuration dedicates a pair of ephone-dns for use as a “press to talk” two-way intercom
between two IP phones. Intercom lines cannot be used in shared-line configurations. If an ephone-dn is
configured for intercom operation, it must be associated to one IP phone only. The intercom attribute
causes an IP phone line (ephone-dn) to operate as autodial for outbound calls and auto-answer-with-mute
for inbound calls.
SUMMARY STEPS
1. ephone-dn dn-tag
2. number number
3. name name
4. intercom directory-number [barge-in | no-auto-answer] [label label]
5. Repeat step 1 through step 4 for the second Cisco IP phone that requires the intercom feature.
6. exit
7. ephone tag
8. button button-number:dn-tag button-number:dn-tag button-number:dn-tag
DETAILED STEPS
Command Purpose
Step 1
Router(config)# ephone-dn dn-tag
Enters ephone-dn configuration mode and configures
the directory numbers for the Cisco IP phone lines.
The maximum directory number is platform
dependent. For details, see the “Memory
Requirements” section on page 1-4.
Step 2
Router(config-ephone-dn)# number number
Configures a valid intercom number for the
Cisco IP phone that receives the intercom.
Step 3
Router(config-ephone-dn)# name name
Configures a username associated with a directory
number to receive the intercom.
“Intercom” is used in place of the name argument.