【作者】 张少华；

【导师】 李成忠；

【作者基本信息】 西南交通大学 ， 计算机应用技术， 2003， 硕士

【摘要】 90年代中期以来，Internet的飞速发展对电信业产生了巨大而深远的影响，基于分组交换网络的多媒体通信系统逐渐成为人们关注的焦点。音频和视频压缩技术、实时数据传输技术及网络技术的成熟，使得在IP网络上实现多媒体通信成为可能。IP Phone作为一种新型的语音通信技术，已经越来越多的渗透到人们的实际生活中。简单地说，IP Phone就是在IP网上实现电话功能。IP Phone技术作为一种以IP网络为传输载体的语音和传真通信技术，在语音传输方面效率高、费用低。IP Phone技术的应用很广泛，特别是与电话网、多媒体技术结合，可以开拓出多种多样的新业务。我们研究IP Phone不仅限于IP Phone本身，更重要的是着眼于IP多媒体通信和IP电话的各种增值业务的应用。而且VoIP作为当前电信业务中发展最迅速的部分，更值得我们深入研究。 基于以上的考虑，本论文应用IP电话的关键技术设计实现了一个广域网环境下的PC到PC结构IP电话软件。并对与IP Phone相关的网络协议，工作原理，关键技术进行了深入的研究。通过对IP Phone的研究，了解和掌握了当前国内外相关领域的发展动态和方向。同时，对该软件进行扩展可以实现可视软件，视频会议系统等业务。 本论文首先讨论了与IP Phone相关的协议、标准、关键技术及其工作原理，然后探讨了语音编码技术，数据包的发送与接收，以及音频录制和播放。并且阐述了PC TO PC结构IP电话的系统分析、系统设计、系统实现。该PC TO PC结构IP Phone软件成功实现了广域网环境下语音录制和播放，经过实践证明，达到了良好的预期效果。并为进一步完善功能打下了坚实的基础。 IP Phone仍然面临着许多问题和挑战，需要人们进一步研究和探讨才能更好的服务于人类。更多还原

【Abstract】 From the 90’s middle period, the fast development of Internet takes great effect on the telecommunication trade, and multimedia communication system based on the packet switching network becomes the focus of people’s concern. Audio frequency and video frequency compression technology, real-time data transmission technology and network technology make it impossible to achieve multimedia communication on IP network. IP Phone is one kind of new sound communication technologies and has taken great effect in actual lives. In brief, IP Phone means achieving phone function on IP network. As one kind of voice and facsimile communication technology based on IP network, IP Phone technology possesses high transmission efficiency and low fee. It has been applied in many broad fields. If combined with phone network and multi-media technology, the IP Phone technology can create various new businesses. We not only research IP Phone itself, but also focus on IP multi-media communication and various IP phone applications. Since VoIP develops quickly in the present telecommunication service, we should research thoroughly VoIP technology.Over these considerations, this paper makes a PC-PC IP Phone software on Internet by IP Phone key technologies. Moreover the paper researches thoroughly network protocols, work theories, key technologies that relate IP Phone. By means of researching IP Phone, I know and master the development trends of IP Phone at home and abroad. By adding some functions, we can develop the software to a video phone software or a video conference system and so on.First of all, the paper discusses protocols, standards, key technologies and work theories that relate with IP Phone. It probes into the speech encoding technologies, sending and reception of data packet, recording and playing of audio frequency. Finally, the paper sets forth PC-PC IP Phone system analysis, system design and system implementation. The IP Phone software successfully makes recording and playing of speech on Internet. And the software achieves well predictive effect in practice. Moreover it makes the substantial base for further improving the functions.IP Phone confronts with many problems and challenges. People should further research and probe into IP Phone to serve human beings.更多还原