摘要：java学习从入门到精通[原创] 作者：robbin 网址：http://hibernate.fankai.com/ java learning path （一）、工具篇 一、 jdk (java development kit) jdk是整个java的核心，包括了java运行环境（java runtime envirnment），一堆java工 具和java基础的类库(rt.jar)。不论什么j......
摘要：测试
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例子：SIP通过网关的呼叫PSTNsip to pstn call through gateway
in the example shown in , the calling sip phone places a telephone call to the pstn through a pstn gateway. the sip phone collects the dialed digits and puts them into a sip uri used in the request-uri and the to header. the caller may have dialed either the globalized phone number 1-202-555-1313 or they may have just dialed a local number 555-1313, and the sip phone added the assumed country code and area code to produce the globalized uri. the sip phone has been preconfigured with the ip address of the pstn gateway, so it is able to send the invite directly to gw.carrier.com. the gateway initiates the call into the pstn by selecting an ss7 isup trunk to the next telephone switch in the pstn. the dialed digits from the invite are mapped into the isup iam. the isup address complete message (acm) is sent back by the pstn to indicate that the trunk has been seized. progress tones are generated in the one-way audio path established in the pstn. in this example, ring tone is generated by the far end telephone switch. the gateway maps the acm to the 183 session progress response containing sdp indicating the rtp port that the gateway will bridge the audio from the pstn. upon reception of the 183, the caller´s uac begins receiving the rtp packets ...
下一页 摘要：软交换技术标准研究进展
石友康
摘 要 下一代网络（ngn)包含了正在发生的网络构建方式的多种变革。软交换是目前各国电信部门的研究热点，也将是电信网络的发展趋势，一些国家正在开展试验，我国有关部门和运营商也已开展了软交换试验。本文主要介绍了软交换体系结构、软交换的标准进展、软交换的主要功能以及需要关注的几个问题等。
关键词 下一代网络 软交换 网络地址转换 服务质量
1 软交换网络......
