197 offers you telco - grade quality lines and excellent back - up support whenever you make idd , std or mobile calls . it is a great alternative to the standard telephony solutions for your company 不论您何时拨打国内/国际长途电话或外地手机，铁通197都能为您提供优质的通话服务。而且无论在高峰或非高峰时段，只要您订购197服务，就可以更加节省话费！
The proliferation of spc exchanges in telecommunication operator ( telco ) networks forced the centralization of supplementary services in special network nodes in order to facilitate the update and introduction of such these services 无线电通讯操作网络中存储控制程序交互系统的增多，促进了各独立网点的附加服务的集中化，以便于这些服务的更新和介绍。
For the last several decades , communications has existed in three separate universes : voice has gone over reserved end - to - end circuits through telco - switches , data has been delivered in packets over equipment maintained by is staff and video has moved over the ether or half - duplex cable 过去几十年中，通信存在于三个独立的领域：话音通过电话公司交换机在预留的端至端电路上传递，数据以包方式在由信息系统工作人员维护的设备上传输，而视频图像在以太或半双工电缆上传送。
