目前移动通信网络主要由电路交换(CS)域，分组交换(PS)域和IP多媒体子系统(IMS)域三个部分构成。
At present, the mobile communication network is mainly divided into three domains which are circuit-switching (CS) domain, packet switching (PS) domain, and IP Multimedia Subsystem (IMS) domain.
湖北省已开通运行的数据及多媒体通信网有：分组交换网、数字数据网、CHINANET及中国公众多媒体通信网等。
The data and multimedia communication networks in service in Hubei province includes PSPDN, DDN, CHINANET and the public multimedia network.
SIP协议已逐步成为下一代网络(NGN)的多媒体软交换系统和第三代移动通信(3 G)多媒体子系统域中的重要协议。
SIP gradually becomes the important protocol in the multimedia Softswitch system and 3g multimedia subsystem area of the next generation network (NGN).
通讯：光纤、数字微波、卫星、程控交换、数据与多媒体等多种通信网络覆盖全区。
Telecommunication: a number of telecommunication networks as optical fiber, digital microwave, satellite, program control switching, data and multimedia cover the whole zone.
通讯：光纤、数字微波、卫星、程控交换、数据与多媒体等多种通信网络覆盖全区。
Telecommunication: a number of telecommunication networks as optical fiber, digital microwave, satellite, program control switching, data and multimedia cover the whole zone.
应用推荐