It is an external modem device which can use for wireless communication. As it is using the 3G HSDPA mobile network for communication, you need to insert a 3G SIM card into the modem. 3G modem with two interfaces for you to use, the serial RS232 com port and USB interface in combo.You can use the serial com port(RS232) or USB interface to get connect with you PC or server to achieve the communication goal. Single PC or Server can connect up to 24 GSM modems with PCI com port interface card or USB interface. For easy management of the 3G modems, 3G Modem Pool is recommended to use.3G modem can be programmed by “AT command”. It is very useful for mobile voice, TCP/IP andSMS communication.

 Basic usage of GSM modem: