l peers you can use, based on their intended purpose: R1-PBX(config)#dial-peer ? Class of Restriction Data type Define the dial peer hunting choice inbound Define the inbound options outbound Define the outbound options search Define dial peer search service terminator Define the address terminate character voice Voice type The only ones we're interested in here are voice dial peers. There are multiple types of voice dial peers, some of which aren't used much anymore. The type of dial peer you choose depends on where you're sending the call: R1-PBX(config)#dial-peer voice 10 ? mmoip Multi Media Over IP Telephony voatm Voice over ATM Voice over Frame Relay Voice over IP The two we are concerned with in this chapter are POTS and VoIP, SO let's take a look at each. POTS dial peers are used for referencing POTS lines. Clever, huh? In our small-office phone system, we've got only one POTS line, SO we need to configure some POTS dial Small-Office VolP Example peers to send our calls there. Since we're only going to send a call to the POTS line if someone first dials 9, let's start with the simplest possible dial peer: R1-PBX(config)#dial-peer voice 1 pots R1-PBX(config-dial-peer)# destination-pattern 9T R1-PBX(config-dial-peer)# port 0/1/0 The destination-pattern says, "Match the number 9, and then continue to capture digits until the timeout value expires.' Imagine picking up a phone and dialing to order 400 copies of Network Warrior, Second Edition, to give as gifts. As you dial, you forget the last four digits of the phone number and hold the phone while you quickly look it up. The phone system will only wait for you SO long before it gives up and delivers a reorder tone (fast-busy) to you. The reason the system waits is because of a configura- tion such as this combined with the interdigit timer. The interdigit timer tells the system how long to wait after each digit is dialed. The T tells the dial peer that the dialed number can be of any length. In this example, the timeout value is configurable on the voice port