The information layer is the highest layer in the network system, mainly transmitting data such as production management information, quality management information, and equipment operation between PLCs, equipment controllers, and production management PCs. The information layer uses the most common Ethernet. It can not only connect PCs on Windows systems, workstations on UNIX systems, but also connect various FA devices. The Ethernet module of the Q series PLC series has an increasingly popular Internet e-mail transceiving function, enabling users to easily send and receive production information e-mails anywhere in the world to build a remote monitoring and management system. At the same time, the FTP server function of the Internet and the MELSEC-specific protocol can easily implement program upload/download and information transmission.