In the Industrial Internet of Things (IIoT), the 4G modem plays a vital role.They are responsible for transmitting data from industrial equipment to cloud platforms for analysis and management.The data transmission between 4G modem and cloud platform depends on various communication protocols.These protocols not only define how data is encapsulated, transmitted and parsed, but also determine the efficiency and reliability of data transmission.
TCP/IP (Transmission Control Protocol/Internet Protocol) is one of the most basic and commonly used communication protocols.TCP is responsible for the reliable transmission of data, while IP is responsible for the routing of data.The 4G modem often uses TCP or UDP in the TCP/IP protocol stack to establish a connection with the cloud platform for two-way data transmission.
MQTT (Message Queuing Telemetry Transport) is a lightweight publish/subscribe messaging protocol.Designed for low-bandwidth, high-latency, or unreliable network environments.In the industrial Internet of Things, the equipment is widely distributed and the network environment is complex.MQTT protocol is widely used because of its low overhead, high reliability and real-time.
HTTP (Hypertext Transfer Protocol) is an application layer protocol for distributed, collaborative, and hypermedia information systems.Although HTTP was originally designed for Web browsers and Web servers,But now it is also widely used for communication between Internet of Things devices and cloud platforms.The 4G modem can upload and download data using the HTTP protocol.
CoAP (Restricted Application Protocol) is a communication protocol designed for the Internet of Things, similar to HTTP.But is more suitable for low bandwidth, low power devices.CoAP uses UDP as the transport layer protocol and provides an HTTP-like request/response model, but is more lightweight and efficient.
AMQP (Advanced Message Queuing Protocol) is an asynchronous messaging protocol used to transfer messages in distributed systems.AMQP provides a reliable message queue service, which supports message persistence, publish/subscribe model, transaction processing and other features.In the industrial Internet of Things, the AMQP protocol can be used to achieve message communication and data synchronization between devices.
Modbus is a serial communication protocol, which is widely used in industrial automation.Although Modbus was originally designed for PLCs (programmable logic controllers),But now it is also used in other types of industrial equipment and sensors.4G modem devices can support the Modbus protocol to communicate with these devices and collect data.
Each of these protocols has its own characteristics and is applicable to different scenarios and requirements. When selecting a 4G modem and the corresponding transport protocol,Factors such as device characteristics, network environment, data transmission requirements and compatibility of cloud platforms need to be fully considered.At the same time, with the continuous development of industrial Internet of Things technology, new transmission protocols will continue to emerge.It provides richer and more flexible choices for the application of industrial Internet of Things.
