SMGP协议是SMGW与其它网元设备（除SMC外）进行短消息传输的接口协议。
非SMC网元设备向SMGW发送或从SMGW接收短消息，这些非SMC网元设备称为ESME。(The SMGP protocol is an interface protocol between SMGW and other network element devices (except SMC) for short message transmission.
Non SMC network element devices are sent to SMGW or receive short messages from SMGW, and these non SMC network element devices are called ESME.)