Why can the 4G LTE router achieve permanent connection?
In the wide application of IIoT, 4G LTE router is the core device connecting physical devices and the digital world, and its stability and reliability are crucial. Compared to home or business routers, the 4G LTE router has undergone many optimizations in design and functionality to ensure permanent connectivity in harsh industrial environments. This article will explore why 4G LTE router can achieve permanent connection from a professional perspective.
I. Durability of Hardware Design

1. Selection of durable materials
   The 4G LTE router uses more durable and reliable materials to cope with harsh industrial environments such as high temperatures, low temperatures, high humidity, and high dust. These materials have excellent anti-corrosion, anti-wear and anti-aging properties, and can operate stably for a long time without being easily damaged.

2. Enhanced power protection
   The 4G LTE router is equipped with enhanced power protection mechanisms, such as wide voltage input, overvoltage protection, undervoltage protection, etc., to ensure stable operation under different power conditions. At the same time, some 4G LTE routers also have built-in backup power or UPS uninterruptible power supply to cope with sudden power outages and ensure network continuity.

3. Redundant design
   To further improve reliability, 4G LTE routers usually adopt redundant design. For example, multiple routers form a network, and when one router fails, other routers can automatically switch to ensure the continuous operation of the network. In addition, some 4G LTE routers also support dual SIM card slots, allowing different operators to back up each other and ensuring uninterrupted network operation.
   II. Stability of software design

4. High-performance industrial processor
   The 4G LTE router is equipped with a high-performance industrial-grade processor, capable of handling a large number of data streams and concurrent connections. These processors have powerful computing power and high-speed cache, which can quickly respond to network requests and ensure the timeliness and accuracy of data transmission.

5. Embedded real-time operating system
   4G LTE routers usually use embedded real-time operating systems (RTOS), which have the characteristics of fast response, low resource consumption, and high stability. RTOS can ensure the reasonable allocation and scheduling of system resources, avoid resource conflicts and deadlock, and ensure the stable operation of the system.

6. Rich communication protocol support
   The 4G LTE router integrates a full range of communication protocols, such as TCP/IP, ICMP, UDP, VPN, DHCP, DDNS, etc., ensuring the stability and efficiency of routing and forwarding for various protocols. These protocols can support data exchange and communication between different devices, meeting the needs of different industrial applications.

7. Heartbeat mechanism
   The TCP protocol inherently incorporates a heartbeat mechanism, serving as the foundation for achieving a permanently stable connection. The heartbeat mechanism can send a data packet to the server at regular intervals, just like a heartbeat, to prove that it is still online. This mechanism can effectively detect the activity of network connections and avoid connection interruptions caused by network or equipment failures.

8. ICMP detection
   ICMP Internet Control Message Protocol is used to detect whether the data transmission at the network layer is successful. When the router detects that the data packet cannot be transmitted, it will send an ICMP message to the sender to inform the reason for the transmission failure. This feedback mechanism helps to discover and solve network problems in a timely manner and ensure reliable transmission of data.
   III. Real-time monitoring and alarm function

9. Real-time monitoring of network status
   The 4G LTE router has the ability to monitor network status and device operation in real time. Through the built-in monitoring system and sensors, the router can monitor key indicators such as network bandwidth, latency, packet loss rate, as well as device operating status and temperature parameters in real time. Once an abnormal situation is detected, the router can immediately handle it and raise an alarm.

10. Alarm mechanism
    The alarm mechanism is an important guarantee for the 4G LTE router to achieve permanent connection. When the router detects network failure, equipment failure or abnormal situation, it will immediately trigger the alarm mechanism and notify the management personnel through SMS, email or sound and light alarm. In this way, management personnel can respond quickly and handle problems, avoiding the expansion of problems and the aggravation of losses.
    IV. Remote maintenance and fault diagnosis

11. Remote maintenance
    The 4G LTE router supports remote maintenance and fault diagnosis functions. Managers can remotely log in to the router through the network to view its operating status, configuration parameters, log files, and other information. At the same time, it can also remotely modify configurations, upgrade firmware, or perform other maintenance tasks, greatly improving maintenance efficiency and convenience.

12. Fault diagnosis
    Fault diagnosis is an important part of remote maintenance. The 4G LTE router has a built-in fault diagnosis system that can automatically detect and analyze the causes of network and equipment failures. When the router detects a fault, it will generate detailed fault reports and diagnostic suggestions to help managers quickly locate the problem and take appropriate measures to solve it.

The reason why the 4G LTE router can achieve permanent connectivity is due to the combined effects of its hardware design's durability, software design's stability, real-time monitoring and alarm functions, and remote maintenance and fault diagnosis capabilities. These features enable the 4G LTE router to operate stably for a long time in harsh industrial environments, providing strong support for the widespread application of industrial IoT. As practitioners of the Industrial Internet of Things, we should fully understand these features of 4G LTE routers and utilize and optimize them in practical applications to promote the continuous development and progress of Industrial Internet of Things technology.