... reliable.Enhanced auto-alarm function, multiple ways of alarm.Optimized RS232 data transmission, full DTU function.Postage control design, timing dial ... - p, Impedance 1kΩ)Communication portRJ45 10M/100M Ethernet port*1, RS232*1, RS485*1Router functionTCP/IP, PPPoE,DDNS, FTP,DNS, DMZ ...