本标准定义了安全和生命安全系统可寻址多路复用、传感器、控制和报警模块的SIA协议。该协议采用双向数字传输方案，可以在双线主干上以低成本实现。中继线还为远程设备供电。协议命令集和响应数据允许在警报条件下，以快速响应模式对任何传感器或设备进行高度可靠、抗错误的模拟和数字消息传输。设备可以以单端或环路配置的任何顺序连接到主干。

This standard defines the SIA protocol for addressable multiplex, sensor, control and annunciation modules for Security and Life Safety systems. This protocol utilizes two way digital transmission scheme, which can be implemented at low cost over a two wire trunk. The trunk also supplies power to the remote devices.The protocol command set and response data allows highly reliable, error resistant transport of both analog and digital messages with fast response mode for any sensor or device in the alarm condition.Devices may be interfaced to the trunk in any order in a single ended or loop configurations.