的Cisco IOS拨号对等：收费绕路以及尾部随下（TEHO）

让我们研究一下这样一个场景，一个公司有使用加利福尼亚州圣何塞的思科统一通信管理器快车（CUCME）路由器和纽约市CUCME系统办事处。在纽约市的路由器将被配置为路由5位局间呼叫圣何塞网络在IP广域网。如果IP WAN不可用，路由器应该配置为重新将呼叫路由到使用11位拨号到从PSTN提供商购买的直接拨入范围408-551-2XXX的PSTN。以下拨号同行来配置此呼叫路由：拨号对等体109的语音VOIP目标模式12 ...偏好1会话目标的IPv4：10.2.1.1！拨号端声音209个盆目标模式12 ...前缀914085512偏好2端口0/0/0：23！拨号端声音203个盆目标模式91 [2-9]。[2-9] ......前缀1端口0/0/0：23在以前的博客讨论的一些配置细节已经从这个讨论中被忽略，所以我们可以专注于参与重新路由到PSTN的呼叫如果主WAN路径是失败的拨号对等体狩猎和数字操纵。所有以数字12开头的5位模式路由默认情况下，基于较低的优先拨号对等体109。如果拨号对等体109不能达到10.2.1.1，拨号对等体209的通话将被重新路由到PRI（端口0/0/0：23）没有任何最终用户干预。拨号对等209个操纵拨号数字（被呼叫方）与9次访问代码前缀的11位模式。 The new pattern matches dial-peer 203 and is routed to the PRI as an 11 digit pattern (access code is stripped). Using this configuration, calls will only be re-routed across the PRI if the destination IP address in unreachable. Call Admission Control (CAC) should be implemented using an H.323 gatekeeper to guarantee call quality. We will cover the Gatekeeper CAC configuration in a future blog. A Tail-End Hop Off (TEHO) dial-peer can be configured to enable toll cost savings for calls routed from NYC to local San Jose, California destinations on the PSTN. TEHO functionality is commonly referred to as least cost routing (LCR) which is enabled in dial-peer 401 below: Dial-peer 110 voip Destination-pattern 91408……. Prefix 91408 Session target ipv4:10.1.1.1 The CUCME device in San Jose must be configured with a dial peer similar to dial peer 203 to match on the 11 digit pattern prefixed with a 9 access code. The San Jose CUCM platform will normally route the call to the local PSTN gateway as a 7 or 10 digit local pattern (each LEC may have different regional requirements). In the next blog, we will investigate inbound and outbound call routing in sites where FXO analog ports are used to connect to the PSTN. We will then begin to explore the exciting world of translation profiles. REFERENCES Cisco IOS Dial Peer Features http://www.cisco.com/en/US/docs/ios/12_3/vvf_c/dial_peer/dp_confg.html Global Knowledge Cisco Unified Communications classes www.globalknowledge.com/go/cisco Cisco Press Books – CVOICE / GWGK / TUC http://www.ciscopress.com/markets/detail.asp?st=44706