Cisco IOS Dial-Peers: Inbound Dial-Peers

下一个拨号对等体示例是入站POTS拨号对等体的示例。Dial-peer voice 1 pots入局被叫号码。t direct - inside -dial端口0/0/0:23注意，Dial-peer 1没有使用destination-pattern命令。拨号点1专门用于呼入呼叫路由。可以利用以前博客中的一个出站PSTN拨号对等点来提供入站和出站呼叫路由，但最佳实践是将一个拨号对等点专门用于PSTN的入站呼叫路由。单个入站拨号点允许使用转换配置文件在入站拨号点上执行数字操作。我们将在以后的博客中介绍翻译概况。我在这个例子中包含了端口标识符，但是如果网关路由器有多个PRI接口，我通常不会引用端口标识符。拨号点1包括两个我们尚未介绍的新命令。如果没有直接向内拨命令，则会给主叫方带来二次拨号音。直接向内拨号命令迫使路由器对收到的数字进行数字分析，以便将呼叫呈现给最终目的地。 The incoming-called number .T command ensures dial peer 1 will pick up all incoming calls sent from the provider to the primary rate interface (PRI) signaling interface (:23 addresses the Q.931 signaling channel). There is a hierarchy of options to matching inbound call legs which is as follows: 1) Incoming called-number 2) Answer-address 3) Destination-pattern 4) Port The incoming called-number command matches against the called party number (DNIS), while the answer-address command matches on the calling party number (ANI). When matching on inbound dial-peers, I normally use one of these two mechanisms. It is important to use these mechanisms when there is a requirement for complex digit manipulation due to tail end hopoff (TEHO) or overlapping number plan conditions. I normally use the incoming called-number . or .T to match on any values the PSTN routes to the site. The destination-pattern string normally matches against the dialed digits (called party number) for the purpose of outbound call routing. Instead of matching the destination-pattern against the dialed digits (called party), the destination-pattern command is analyzed against the calling party (ANI) for inbound calls. I have never used a destination-pattern to match against ANI on an inbound call, but I have had plenty of troubleshooting scenarios where the wrong inbound VoIP dial-peer is selected because the destination-pattern matches the remote sites calling party information. Debugging inbound call routing dial-peer selection is best done with the “debug voip dialpeer” command. This command will display debug output for both POTS and VoIP dial peers. The port mechanism is only used with POTS dial peers if there is no other mechanism available. Let’s consider an example where Global Knowledge has a 5 digit dial plan at a site and the carrier PRI circuit was ordered to provide only the last 5 digits of the dialed number. Dial peer 1 will match the inbound call leg, but the second call leg will be a VoIP dial-peer that forwards the 5 digits to Cisco Unified Communications Manager. In the next blog, we will begin discussing VoIP dial peers.