... TCP/IP modem, Support transparent data transfe, gprs ip modem, gsm modemgprs modem with rs232 rs485 io for m2m meter readinggprs ... multi online trigger ways, including SMS, ring and data. Support link disconnection when timeoutSupport dynamic domain name(DDNS) and IP access ... and BandEGSM900/GSM1800MHz, GSM850/900/1800/1900MHz(optional)Compliant to GSM phase 2/2+GPRS class 10, class 12(optional) ...