Both Signalling and user data may be subject to ciphering.
信令和用户数据都应被加密。
2
The present document specifies the standards for user data transport protocols and related signalling protocols to establish user plane transport bearers over the S1 interface.
文档对数据传输协议和相关的通过S1接口建立用户平面传输承载的信令协议进行了详细的说明。
3
To this end, the requirements of the telephone service, the data transmission service and the signalling network management, in particular, were investigated.