icit match wins. Let's say we have two dial peers that look like this: dial-peer voice 3 voip destination-pattern 222. session target pv4:10.10.10.10 dial-peer voice 4 voip destination-pattern 2222.. session target ipv4:20.20.20.20 If you were to dial 222111, dial peer 3 would match. If you were to dial 2222111, dial peer 4 would match, even though the number also matches the pattern in dial peer 3. Be careful, though, because when it comes to nonexplicit matching, the shortest will win. Let's look at another example: dial-peer voice 10 voip destination-pattern 2. session target ipv4:10.10.10.10 dial-peer voice 20 voip destination-pattern 2 session target ipv4:20.20.20.20 With these two dial peers, if I dial 2111111, it will match dial peer 10, even though you may perceive dial peer 20 to be a better match. Inbound dial peers. Inbound dial peers are evaluated in the following order: 1. Called number with incoming called-number command 2. Calling number with answer-address command 3. Calling number with destination-pattern command 4. Voice port configuration Chapter 30: VolP 5. Default dial peer 0 My examples in this chapter are very simple, SO I've stuck with destination-pattern, since all my incoming calls will be automatically sent to a single extension as a result of the plar 111 command on the voice port. SIP has become a very popular protocol for a lot of reasons, not the least of which the fact that it's an open standard. Many providers are now offering SIP trunks that allow businesses to serve their primary phone services over their existing Internet links. SIP devices are called user agents. A user agent can be a user agent client, a user agent server, or both. As you might expect, an IP phone will generally be a user agent client. Our CME PBX will also be a client, since we'll need to register with a server at the provider's network to make outbound calls. If we were using SIP phones, then it could be a user agent server as well. There are four types of servers you'll likely encounter: Proxy server Also 