open relay meaning in English

开放式电驿
开式继电器

In this diagram , a single - pole normally open relay is controlling the connecction of the voltage source to the lamp
在该图中，一个单刀常开继电器控制着电压源和照明灯之间的连接。
The simple mail transfer protocol emulation is capable of acting as a open relay server , the perfect trap for hackers looking for a target to relay spam
简单邮件传输协议仿真能力作为一个开放的中继服务器，完美的陷阱，黑客在寻找一个目标，以接力的垃圾邮件。