Updated: Jun 1, 2019
An IoT gateway is one of the most critical components of future internet of things systems. It also be an essential component of IoT solutions. Be an IoT and Smart Solutions Hub, It aggregates sensor data, translates between sensor protocols, processes sensor data before sending it onward and more. The importance of IoT gateway is understandable when you consider the explosion in connected smart "things" that has occurred over the past few years.
A gateway's role in the IoT ecosystem
As shown in Figure 1, IoT gateways sit at the intersection of Iot systems -connected devices, controllers and sensors - and the cloud.
Today’s "smart" IoT gateways delivered by companies such as Dusun are full-fledged computing platforms running Linux operating systems. They open up huge opportunities for IoT solution providers to push processing closer to the smart devices, improving responsiveness and supporting new operating models.
Besides, many computing functions can be made to order. The IoT edge gateways delivered by Dusun with full onboard processing would allow the gateways to filter out routine information and pass through the alerts that are worthy of attention. Going even further, these gateways can perform their own analytics and operations on the data -- such as determining that the temperature is too high in part of the building -- and can then use that insight to take independent action, such as turning on the air conditioning or opening vents.
Gateways also allow sensors/devices to communicate over shorter distances, boosting battery life. It also reduces latency in time-critical applications by performing processing on the gateway itself rather than in the cloud.
Protocols a gateway communicates with sensors
A complete IoT application might involve many different kinds of sensors and devices. For examples, you might want sensors for temperature, moisture, and sunlight and devices such as intelligent lock, people counter, etc.
All of the different sensors and devices can use varying network connectivity types. Connectivity types include LPWAN, Wi-Fi, Bluetooth, and Zigbee, NB-IoT, among many others. And each of them may connect to different control environments and have different models for management and security. The Dusun gateways supports most protocols for these connectivity types and suit for many applications. Common connectivity protocols include BLE（4.x/5.0/Mesh）, ZigBee 1.2/3.0, Z-Wave, TCP/UDP. The left part of figure 2 shows the protocols used by Dusun’s gateways to ‘chat’ with sensors and devices.
How a gateway ‘talks’ with Clouds?
As stated above, Gateways communicate with sensors/devices over varying connectivity types, and then pre-process and filter the data being generated by sensors/devices to decrease transmission. Finally, the processed data are translated into a standard protocol such as MQTT to be sent to the cloud through internet connections.
There are some ways including WIFI, NBIot, 2G/3G/4G cellular, wired connection that gateways delivered by Dusun connect to the internet. Dusun supports popular MQTT and custom made protocols such as web-socket. The right part of figure 2 shows the protocols used by Dusun’s gateways to ‘talk’ with clouds.
Gateways’ scalability and programmability
Flexible smart gateways should be built on open standards and committed to keeping pace with evolving IoT protocols, standards, and technologies as well as offering third-party integrations and robust APIs. The Dusun smart gateways support most IoT protocols, standards. Besides, Dusun smart gateways are programmable which means they support extended or secondary development.
Dusun provides SDKs and APIs which can be used to let customers make their programs to control the data transfer procedure and use their security mechanism. This means customers can get the data from the edge devices/sensors, process the data and translate the data into MQTT which will be sent to the clouds through their methods and security algorithms.
Gateways’ security issue
Every sensor/device that is connected to the internet becomes vulnerable to being hacked. Hacked sensors/devices are bad. Not just for the owner, but for everyone else too.
Gateways reduce the number of sensors/devices connected to the internet because the sensors/devices are only connected to the gateway. However, this makes gateways themselves targets and also the first line of defense. This is why security needs to be a priority for any gateway. Many companies including Dusun adopt some measures to enhance the security capability of the gateways to ensure the integrity of the network and system in both directions.
Dusun’s IoT gateways support the following functionality:
1. Protocol and data bridge -- translate and transfer data among and between systems operating with different communications protocols and data formats.
2. Storage and analysis – preprocess and storage received data and do some analysis to help decision-making
3. Management -- the ability to provision, update and control access of connected devices
4. Scalability and flexibility – SDKs and APIs supporting popular protocols are provided to let customers do extended development
5. Trusted connectivity and security – ensure the security and stability of data transmission and system
In conclusion, Dusun’s smart gateways has good performance and can be used for many Iot applications.
Please click here to check Dusun's programmable smart hub.