command receiver meaning in English

指令接收机
指令接收器

If the sequence number of a command is identical with the sequence number of a command that has been received before , and the contents of the two commands are identical too , then the receiver shall discard the command ; if the sequence numbers of two commands are identical while their contents are different , then the command receiver shall return an error code in the response
如果命令的序列号和以前接收到的命令的序列号相同，且命令内容也相同，则接收方丢弃该命令；如果序列号相同，但是命令内容并不相同，则命令接收方在应答中返回错误码。