25
In this example, West users can dial 5 and a four-digit extension to reach telephones in the East office. East users can dial 5 and
a four-digit extension to reach telephones in the West office.
The West router connects to the PBX through an E&M VIC port 0/0. This port is associated with a POTS dial peer for incoming
calls. But you no longer need to associate every telephone number with its own port. Instead, you can configure a local dial peer
as if all the West telephones (represented by a wildcard destination pattern) are connected directly to this port, as shown in the
following commands:
West> enable
Password:
West# configure terminal
West(config)# dial-peer voice 111 pots
West(config-dial-peer)# destination-pattern 1408555....
West(config-dial-peer)# port 0/0
Configure VoIP dial peers for outgoing calls and associate destination phone numbers on the East router with that router IP
address, as shown in Figure 21, and in the following commands:
West(config)# dial-peer voice 121 voip
West(config-dial-peer)# destination-pattern 1919555....
West(config-dial-peer)# session target ipv4:192.168.11.3
West(config-dial-peer)# exit
West(config)#
Figure21 Linking PBXs over the IP Network (Remote Dial Peers)
Now configure number expansion so that numbers beginning with 5 (belonging to the East office) and sent by the West PBX to
the West router are expanded into the full destination pattern:
West(config)# num-exp 5.... 1919555....
Note You do not need to configure number expansion for calls from one West telephone to another West telephone because
the PBX switches those calls.
Finally, enter the following global configuration voice-port command to configure the E&M port:
West(config)# voice-port 0/0
West(config-voice-port)# signal immediate
West(config-voice-port)# operation 4-wire
West(config-voice-port)# type 2
West(config-voice-port)# shut
West(config-voice-port)# no shut
Note For these commands to take effect, you have to cycle the port by using the shutdown and no shutdown commands.
Note Configure the PBX to pass all dual-tone multifrequency (DTMF) signals to the router.
22343
West East
408 555-xxxx
E&M VIC
0/0 919 555-xxxx
192.168.11.3
dial-peer voice 121 voip
destination-pattern 1919555….
session target ipv4:192.168.11.3
num-exp 5…. 1919555….
PBX PBX
Source Destination
IP cloud