I'm Rob Faludi, Chief Innovator for Digi International, and today I'm going to give you some information to help decide between mesh networking and cellular technology for your Internet of Things application.
Mesh networking allows you to extend the reach of your device network by allowing data to hop from device to device, so that radios too far apart to hear each other directly can still communicate.
In cellular technology, each device communicates through the cellular network, but never directly with each other. Here's a quick comparison.
Mesh networking is a good solution when you have many devices in the same location or any time cellular coverage is not available. It's good for networks where devices talk a lot to their local neighbors, and when communication between these devices is frequent.
For example, mesh networking is a popular choice for municipal street lighting control. Street lights typically are placed very close together, so you have many in the same location. They may interact locally, for example, if one street light goes out, its two neighbors may want to sense that, and then turn up their brightness to compensate. Automated joining and self-healing help keep the street light network stable.
Cellular networks are a good choice when there are relatively few devices per location, say, 5 or 10 on each local site. It's great when devices are mostly talking to the cloud and have little need to talk to each other. Of course, cellular coverage has to be available, and because you'll be paying for a data plan, you'll want to keep communications short and to the point. Cellular is a popular choice for applications like tank monitoring.
Let's say diesel fuel tanks for emergency generators. You'll want to know the current condition and fuel level of each tank. There are typically few nodes per location, and they only need to communicate once in a while, to state the current fuel level or to send an alarm if there's trouble. Because these devices are remotely located, Wi-Fi or wired ethernet typically is not available, and because each talks directly to the cloud, no interaction between the devices themselves is required.
There are a lot of exciting developments happening right now in the cellular world. New LTE networks have begun supporting protocols that are optimized for lower bandwidth communications, over longer ranges that use less power. Two protocols that you might hear a lot about are LTE Cat M1 and NB-IoT.
As these new networks roll out, the cost of cellular networking will fall, and many new and interesting applications will become possible. If you want to know more about mesh or cellular networking, Digi International has an extensive library of documentation, plus mesh and cellular experts to help you make the best choice your application.