基于Asterisk构建中小型公司IP-PBX通信系统的研究

【作者】 王继鹏；

【导师】 张维；

【作者基本信息】 西北工业大学 ， 软件工程， 2007， 硕士

【摘要】 随着网络和计算机技术的迅速发展，通信系统越来越依赖于计算机和网络，要求通信系统不仅具有更高的可用性，而且还要具有更大的可扩充性和兼容性，以降低系统总的开发维护成本。近年来，电话通信、电子邮件通信和网络通信的融合更是当前通信发展的主流方向。IP电话的出现对传统的PBX带来了巨大的冲击，基于IP技术的新一代分布式PBX系统具有更广阔的应用前景。本文采用开源的软件包-Asterisk，在一台计算机上来搭建了IP-PBX系统，同时对IP-PBX系统同其它软件服务器相融合来组建中小型公司的多种用途的通信系统。 随着IP-PBX系统在中小型公司中越来越普及，实现也越来越简单，成本的降低便成为普遍关注的重点。另一方面便是语音服务质量和系统的安全。这就是IP-PBX用户普及所受的限制。开源的软件包Asterisk无疑将成为中小型公司布局IP-PBX系统的首选之一。因为目前网络“软电话”逐渐开始流行，通信价格开始降低，故电信业的未来前景便是IP-PBX通信系统。 本文首先介绍了IP-PBX的基本概念、关键技术和课题背景及其优越性；其次对IP-PBX通信系统的组成和相关协议进行了研究，讨论了IP-PBX通信系统的基本协议，如SIP、IAX等协议；然后给出了基于Asterisk实现IP-PBX通信系统的原理和基本通信的实施方案；接下来论述了利用Asterisk构建中小型公司中IP-PBX系统的整体方案及其所需的软硬件基础。同时给出利用Asteirsk实现IP-PBX的构建，简单设计的呼叫设计图和流程图。在此基础上，使用UM(unified Messaging)的理念，融合当前几种较为流行的IM、FAX服务器软件和Open-Xchange来搭建适应于公司通信和业务处理的平台。同时分析了影响语音的因素和优化语音服务质量的一些基本措施。最后给出了系统设计的安全问题，同时针对当前网络攻击的主流DoS攻击，给出了侦测算法和恢复算法，便于公司考虑布局的安全设计。 本文最后给出了一些对未来该领域发展的展望。更多还原

【Abstract】 With the rapidly developing network and computer technology, the communication depends on the computer system and network technology more and more. The communication system with the higher usability and the greater expandability and compatibility is demanded in order to reduce the maintenance cost of the system development. Recently, the telephony、E-mail and network become the major way of the communication. The emergence of IP phone brings about great impact on the traditional PBX system. A new generation of distributed PBX system based IP technology has wide applications. This paper uses the Asterisk software package to build the IP-PBX system on a computer. Using this IP-PBX system integrates with other software server to build the small-middle enterprise communication system.With the IP-PBX systems developing in the small-middle enterprises, the implement becomes simple. So the more and more companies emphasises on the Asterisk in the future. While voice QoS and security is always the problem for the IP-PBX system popular. Currently, the SIP protocol metures and the most companies are puploar it. So, the SIP softphone is puploar in network. As the reuslt, the communication’s price becomes low. I trust the futuer the telcom is the IP-PBX system.At first, the basic concept, key technologies of IP-PBX and the subject background are introduced. Then, we investigate and discuss the structure of IP-PBX system and the associated protocols, such as SIP protocol and IAX protocol and so on. After that, the whole scheme of IP-PBX system based on Asterisk and the implementation frame of its components are presented. So, we can use the Asterisk to build the small-middle enterprise communication system. In this foundation, use the Asterisk to integrate the several popular communication ways, for example , IM、 FAX and the Open-Xchange, which to build the small-middle enterprise business and communication platform. Using the UM (unified messaging), can integrate IM, FAX, analog phones and softphones and IP phones, e-mail and voice mail within one platform. The papar give the function about Asteirsk implementing the IP-PBX, and the design chart and flow chart. The paper analysies the problem about the voice Qos and give some measuers to optium the problem. At the last, the parper give some更多还原