How does the Cellular IP Modem DTU work?

The serial device (PLC/MCU/PC, etc.) is connected to the industrial DTU/Cellular IP MODEM terminal serial port through the RS232 or RS485 interface, and the device can encapsulate the transmitted data through the industrial DTU/IP MODEM device for network protocol encapsulation, and then through the 5G / 4G / 3G wireless network transmission to the data center.

How does the industrial DTU/IP MODEM work? The following is an example of Alotcer AD7028.

Industrial IP MODEM Alotcer AD7028
After the Alotcer AD7028 is connected to the power supply, according to the dial-up process, first log in to the 5G/4G wireless network. After the dial-up is completed, the AD7028 device will get an internal IP address, which is randomly designated by the operator, because the IP address will change every time you dial. We can regard the AD7028 device as a device on an internal LAN, which can communicate with the Internet outside. This method is similar to a computer on a local area network accessing an external network through a gateway.

Industrial IP MODEM Alotcer AD7028 actively initiates a communication connection with the data center and keeps the communication connection always existing. Due to the above situation, only the AD7028 can actively connect to the data center, but not the data center. This requires the data center to have a fixed public IP address or a fixed domain name. The public network IP address or fixed domain name of the data center is stored in the industrial DTU as a parameter, so that once the dial-up is successful, it can actively connect to the data center.

All in all, industrial DTU/IP MODEM can perform TCP or UDP communication to the data center according to parameters such as IP address and port number. Upon receiving the response from the data center, the industrial DTU/IP MODEM is considered to have successfully connected to the data center and will continue to maintain the communication connection. If the communication connection is cut off, it will reconnect. After the TCP/UDP communication connection is established, data bidirectional communication can be carried out.

Cellular IP Modem

Through two-way communication with the data center, the conversion from the user’s serial port to 5G/4G data packets is realized, which is a relatively easy process to implement. When the user’s serial data is received, IP MODEM will immediately package the serial data in the form of TCP/UDP and send it to the data center. On the contrary, when receiving the TCP/UDP data packet from the data center, extract the data content from it, and transmit it to the user equipment through the serial port. Through the wired data acquisition center, two-way communication between various industrial MODEMs can be realized. This is currently the most common application system.

Other Related:
Download address of Virtual COM software: Contact us
Click here to learn Alotcer’s Cellular IP Modem products.