软交换网络及其研究进展

论述了软交换网络的概念、技术特征、网络的分层结构及各层的主要功能。阐述了软交换在下一代网络（NGN）中的定位及二者之间的联系与区别。介绍了贝尔实验室针对话音网络提出的Lucent软交换网络方案，总结了国际及国内软交换研究所取得的进展，包括协议、网络解决方案及商用实验等。指出了软交换网络今后需要关注的几个方面，如服务质量、网关、安全性、业务提供方式、与现有网络的有机结合等。

Softswitch Network and Its Research Development

The paper introduces the concept of softswitch network, as well as its technical features, network architecture and each layer＇s function, and describes the relationship and differences between softswitch and next generation network （NGN）. The paper introduces the Lucent softswitch scheme proposed by two Bell Lab researchers for telecommunication, and summarizes the research achievements in China and other countries, including protocols, network solutions, business experiments and so on. Finally, the paper points out some factors of great importance in the future of softswitch, such as QoS （quality of service）, gateway, security, methods of service provision and compatibility.