Why Use IoT Gateways?

In both smart projects and the consumer scenarios of smart homes, the application of the Internet of Things (IoT) is involved. With the advancement of network technology, IoT applications are becoming increasingly popular.

Most IoT applications are formed through the self-detection capabilities of sensors, combined with network transmission, computing, and big data technologies, achieving more automation and intelligent applications, making various smart projects more attractive.

The IoT generally consists of three parts. Sensors, gateways, and platforms are the three main modules that make up IoT applications, and their working principles are relatively simple.

Various IoT Sensors

By detecting events through various sensors, the events are aggregated through the gateway and transmitted to the platform, where they are summarized, analyzed, and applied, achieving a closed-loop application logic in an IoT environment.

In this process, why do we need to use an IoT gateway? Can’t we directly upload the sensor data to the IoT platform? Of course, this is also possible, and many IoT applications indeed use this method. However, there are also some that need to cooperate with gateway applications. So why should we cooperate with gateway applications, and under what circumstances should we use an IoT gateway?

In the overall IoT solution, various transmission protocols are involved. Many sensors use protocols such as Zigbee, LoRa, Bluetooth, etc., to transmit data. However, IoT platforms are deployed in network environments and need to transmit through links such as 4G, WIFI, and wired connections, using methods like HTTP, HTTPS, and MQTT over TCP. This requires a gateway for conversion.

IoT Gateway Working Architecture

For example, in a certain project, due to the remote and open environment on-site, the operator’s network signal coverage is poor, so a LoRa base station and gateway were deployed on-site. Then, a large number of sensors communicate with the gateway using LoRa. The gateway has 4G internet capability and converts the collected IoT data to MQTT protocol, sending it back to the IoT platform server via 4G.

Additionally, the IoT gateway plays a role in data processing. The data collected by sensors may not all be necessary data; it may contain a lot of unnecessary data, or its data format may differ from the application’s format, all of which require the gateway to process, format, summarize, filter, preprocess, denoise, and compress the data.

In fact, data preprocessing can also be considered a form of edge computing. However, in some advanced applications, pre-analysis and preprocessing of IoT data can be conducted within the IoT gateway, allowing for rapid responses based on conditions. When an anomaly is detected, an alarm can be issued immediately without waiting for cloud processing.

Edge Computing Capability of IoT Gateways

For instance, in some chemical application scenarios, the time from when some sensors detect a problem to when it poses a destructive threat is very short. If there is a delay in alarm due to network issues, the losses can be substantial.

Moreover, regarding the management of IoT sensors, local management of various sensors through the IoT gateway is more intuitive, including identity security authentication, remote upgrades, and monitoring of device status, all of which offer more flexibility.

The IoT gateway also acts as a firewall, serving as an isolation device between the sensor network and the internet. Through security policies, it can reduce network attacks against sensors, effectively protecting device and data security. Additionally, data encryption can be performed at the gateway, providing more confidential data during uploads.

Comparison of Several IoT Transmission Protocols

In IoT applications, the use of gateways is very common, including our smart homes, which also deploy a gateway device to control various switches and sensor devices. Of course, this is not absolute; many sensor devices themselves support WIFI and 4G internet capabilities, directly transmitting data to the IoT platform. 4G and 5G networks have designed specific protocol standards for IoT, and applications like NB-IoT and LTE-M are also very common. Therefore, in IoT projects, the choice of method and standards is crucial, as different scenarios require different gateway devices.