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& l3 [' Z7 @' V, O' }理解SIP中继(中英对照)& s# o5 h: r0 n
在我们学习SIP协议的过程中,对于一个概念要清楚,那就是SIP中继的概念。为了让大家更好地理解这方面内容,我们采用中英文互译的对照形式,帮助大家了解这方面的知识,具体资料如下:
4 f0 \: ^, l( P1 K7 f A SIP Trunk is a logical connection between an IP PBX and a Service Provider’s application servers that allows voice over IP traffic to be exchanged between the two. When a call is placed from an internal phone to an external number, the PBX sends the necessary information to the SIP Trunk provider who establishes the call to the dialed number and acts as an intermediary for the call. All signaling and voice traffic between the PBX and the provider is exchanged using SIP and RTP protocol packets over the IP network.8 A( Y9 A, F% Z2 x
一个SIP中继是一个IP PBX和服务提供商的应用服务器,使语音的逻辑联系 IP流量 将两者之间的交换。当一个呼叫从内部到外部电话放在号码,交换机发送必要的信息提供者的SIP中继谁建立了调用拨打的号码,并作为为调用中介行为。所有的信号和 语音通信 交换机之间的交换和提供者是通过IP使用SIP和RTP协议包 网络。
- n+ B9 @, _7 d4 ] If the number being called is a traditional PSTN telephone, the trunk provider routes the IP packets to a PSTN Gateway that is closest to the number being called, to minimize possible long distance charges. The provider can also terminate PSTN numbers, and route incoming calls for those numbers back to the IP PBX over the SIP can also Trunk. This allows businesses to offer local phone numbers in several geographical areas, but service them all from a single location.
4 j' o2 ^% H c 如果数字被称为是一种传统的PSTN电话,树干提供IP数据包路由到PSTN网关是最接近的号码被称为,以尽量减少可能的长途电话费。提供者也可以终止的PSTN号码,并在园区路线为这些号码来电返回的IP PBX还可以干。这使得企业能够在几个地理区域提供本地电话号码,但服务从一个位置全部。
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If the number being called can be reached over a SIP Trunk, the call does not need to be routed over the PSTN, but can be carried on the IP network end to end. Providers can deliver these calls to their customers for very little cost, and many offer them at no charge. Some service providers have agreements and exchange calls for each others customers directly over their IP networks. Where no such agreements are in place, calls are routed over the PSTN, even though both endpoints may ultimately be reachable over a SIP Trunk. |