What is the working principle of industrial 4G router?

The industrial 4G router is a SIM card, which provides users with wireless long-distance data transmission function by using the 4G LTE network. Generally, it has RS232 (or RS485/422 serial port), LAN port and WAN port. It can connect serial port devices, Ethernet devices at the same time, and mobile terminal devices through WIFI signal to realize wireless data transparent transmission. This is the working principle of the industrial 4G router in the process of using, so what is the networking principle of the industrial 4G router?

working principle of industrial 4G router
The industrial 4G router works in the third layer (network layer) of the seven-layer network protocol. The industrial router receives a network packet at the network layer and forwards it to the destination address contained in the packet. Therefore, when industrial routers transmit data, they first need to find the target address from the data packet, add the next MAC address before the frame lattice, and at the same time, the TTL domain value of IP data header begins to decrease, and recalculate the checksum. The working principle of industrial router is the same as that of router, which can find the routing table in the device according to some routing communication protocol.

In the network, each industrial router updates the routing table according to certain rules to maintain the validity of routing information, transmits messages to the network, and then according to the rules, the industrial router sends the data packets with appropriate size, and then sends these data packets according to different or the same path. When the data arrives at the destination, the decomposed packets are packaged into the original message form in sequence.

The main task of industrial router is to find an appropriate transmission route for each data packet and transfer data to the destination. Industrial router transmission usually has public channel, VPN/APN virtual private channel, or encrypted transmission. It mainly depends on the data form transmitted by industrial routers to decide what channel mode to use. Therefore, different transmission modes of industrial routers are applied to different project application scenarios.