Building Blocks of Building an IoT Product – The Communication Channel
We are a step closer to building our first DIY IoT project. In previous articles, we read about the IoT ecosystem and development boards available to quickly build IoT projects. If not I would recommend going through the Building Blocks of Building an IoT Product first.
While building an IoT project, you have to decide which way you want to send data to the cloud server or vice-versa. It largely depends upon your project and its scope. e.g. if you are building a smart weather station located in a remote area you would most likely prefer a cellular network vs building a smart light located inside your house can be connected using home Wifi. But if you are building multiple smart lights and other components for smart home then you would like to go with some sort of mesh network where all components send data via mesh to a gateway which forwards data to the cloud service.
In recent years with the growth of IoT, new communication technologies have emerged. There are two major requirements for any IoT application – extremely low power usage and low-cost widely available connectivity. Now it is important to understand that cellular connectivity has wide availability but it is neither low cost nor low power usage. In fact, the cellular module used the maximum power in your board.
Technologies like LoRaWan, Sigfox solve this exact problem. These are the network in itself and slowly spreading all across the globe. NB-IoT, LTE CAT M are other competition to SigFox and LoRAWAN using existing cellular network with low cost, low power usage features.
Wifi and cellular are well understood so I am skipping the two. Let’s discuss little more about the new network for the Internet of Things.
LoRaWAN is a protocol specification built on top of the LoRa(Long Range, Low Power) technology developed by the LoRa Alliance. It uses unlicensed radio spectrum in the Industrial, Scientific, and Medical (ISM) bands to enable low power, wide area communication between remote sensors and gateways connected to the network.
Sometimes people get confused with LoRa and LoRaWAN, LoRaWAN is the communication protocol and system architecture for the network while LoRa is the physical radio layer enabling the long-range communication link.
The LoRaWAN protocol and network architecture directly influence the battery life of a node, network capacity, quality of service, security, and the variety of applications served by the network. If you know more about LoRaWAN and myths please head over to 11 Myths About LoRaWAN.
Frequency band supported by LoRa in the different country varies based on the country-specific unlicensed band. Below is the current list of supported frequency bands. Make sure to get the right LoRa module for your project –
It is important to mention about The Thing Network. It is the largest crowd-sourced LoRaWAN network with which you can connect your IoT devices. If it is unavailable in your area, you can buy a LoRa gateway and connect it with The Thing Network to provide LoRaWAN connectivity in your area.
Sigfox is similar technology to LoRaWAN in terms of operations. Its application and purpose are also similar. I will not go into more detail in Sigfox. If you have the option to select between LoRaWAN and Sigfox go for LoRaWAN.
NB-IoT & LTE-M1
Narrowband IoT or NB-IoT and LTE-M1 are other LPWAN (Low Power Wide Area Network) technology built on existing LTE network for IoT applications.
Both the technologies are still not widespread and only available in a few geographies. Yitaek has a good write-up on NB-IoT and LTE-m1.
Mesh Network (Zigbee, Thread, RF)
Mesh is my new favorite. If you are developing a smart home, smart factory kind of IoT applications and you need to connect multiple sensor nodes spread all across the premise then mesh is the best-suited network topology for you.
In definition, Mesh networking is a type of network topology in which a sensor node (device) transmits its own data as well as serves as a relay for other nodes. Routers are used to provide the best and most efficient data path for effective communication. In the event of a hardware failure, many routes are available to continue the network communication process.
If you remember from my previous article about IoT Hardware. I did mention a new range of Particle’s product Xenon, Argon, and Boron. They are built on top of a Mesh Network protocol called Thread. Google Nest devices used the same protocol for communication.
Mesh network in itself a quite big topic and very fascinating as well. You can implement mesh using almost any sort of network for wide area coverage. e.g. Zigbee, RF, Bluetooth modules can be used to build a decent mesh network.
That is all about communication in IoT. You can deep deeper into any specific technology which interests you to know more. My purpose for the article was a fair introduction to new communication channels in a more practical way. Stay tunes for next article on cloud service and then we are all set for our first IoT DIY project.