Table Of Contents - Cisco 3600 Series Configuration Manual

POTS peers associate a telephone number with a particular voice port so that incoming calls for that
telephone number can be received and outgoing calls can be placed. VoIP peers point to specific
devices (by associating destination telephone numbers with a specific IP address) so that incoming
calls can be received and outgoing calls can be placed. Both POTS and VoIP peers are needed to
establish Voice over IP connections.
Establishing communication using Voice over IP is similar to configuring an IP static route: you are
establishing a specific voice connection between two defined endpoints. As shown in Figure 8, for
outgoing calls (from the perspective of the POTS dial peer 1), the POTS dial peer establishes the
source (via the originating telephone number or voice port) of the call. The VoIP dial peer establishes
the destination by associating the destination phone number with a specific IP address.
Figure 8 Outgoing Calls from the Perspective of POTS Dial Peer 1
Source
Dial peer 1
Voice port
1/0/0
(408) 555-4000
POTS call leg
To configure call connectivity between the source and destination as illustrated in Figure 8, enter the
following commands on router 10.1.2.2:
dial-peer voice 1 pots
destination-pattern 1408555....
port 1/0/0
dial-peer voice 2 voip
destination-pattern 1310555....
session target ipv4:10.1.1.2
In the previous configuration example, the last four digits in the VoIP dial peer's destination pattern
were replaced with wildcards. This means that from access server 10.1.2.2, calling any number string
that begins with the digits "1310555" will result in a connection to access server 10.1.1.2. This
implies that access server 10.1.1.2 services all numbers beginning with those digits. From access
server 10.1.1.2, calling any number string that begins with the digits "1408555" will result in a
connection to access server 10.1.2.2. This implies that access server 10.1.2.2 services all numbers
beginning with those digits. For more information about stripping and adding digits, see the
"Outbound Dialing on POTS Peers" section.
Figure 9 shows how to complete the end-to-end call between dial peer 1 and dial peer 4.
IP cloud
Dial peer 2
10.1.2.2
VoIP call leg
Configuring Voice over IP for the Cisco 3600 Series VC-27
Inbound versus Outbound Dial Peers
Dial peer 3
Voice port
1/0/0
10.1.1.2
Destination
Dial peer 4
(310) 555-1000