EKI-1521 and EKI-1522 feature two independent Ethernet ports and MAC addresses to provide a redundant networking mechanism to guarantee Ethernet networking reliability. EKI-1521 and EKI-1522 are serial device servers that connect RS-232/422/485 serial devices, such as PLC, meters, sensors, and bar code reader to an IP-based Ethernet LAN. They allow nearly any device with serial ports to connect and share an Ethernet network. EKI-1521 and EKI-1522 provide various operations: COM port redirection (Virtual COMport), TCP Server, IP Client and UDP mode. With COM port redirection mode, standard serial operation calls are transparently redirected to the EKI-1521 and EKI-1522, guaranteeing compatibility with legacy serial devices and enabling backward compatibility with existing software. With TCP server, TCP client, and UDP modes, EKI-1521 and EKI-1522 ensures the compatibility of network software that uses a standard network API. Moreover, you can make serial devices communicate with other devices peer-to-peer, without any intermediate host PCs and software programming.