LoRaWAN uses a star network topology—similar to a Local Area Network. All the end nodes connect to LoRaWAN gateways, which connect to one central network server. With LoRaWAN, IoT manufacturers can build or buy their own network infrastructure or find a provider that serves the area they want to deploy.
There are several key reasons manufacturers look to LoRaWAN for their IoT connectivity needs, and it’s one of the most popular types of LPWANs. But this technology has some major shortcomings as well. Before we get to that though, there’s an important distinction you should know about.
The difference between LoRa and LoRaWAN
It’s not uncommon to hear LoRa and LoRaWAN used interchangeably, but they’re two different things.
LoRa (Long Range) is an LPWAN protocol that defines the physical layer of a network. It’s a proprietary technology owned by Semtech (a chip manufacturer) that uses Chirp Spread Spectrum to convert Radio Frequencies into bits so they can be transported through a network. LoRa is one of the technologies that makes LoRaWAN possible, but it’s not limited to LoRaWAN, and it’s not the same thing.
LoRaWAN (Long Range Wide Area Network) is an upper layer protocol that defines the network’s communication and architecture. More specifically, it’s a Medium Access Control (MAC) layer protocol with some Network Layer components. It uses LoRa, but it specifically refers to the network and how data transmissions travel through it.
Advantages of using LoRaWAN
LoRaWAN is a pretty unique networking technology. Here are some of the main reasons why IoT manufacturers find it appealing.
Unlicensed frequency bands
While cellular carriers each primarily operate on licensed frequencies, all LoRaWAN networks use specific unlicensed frequencies that vary by country. This means that if you own your LoRaWAN infrastructure, you don’t pay for data usage—however, you’re stuck maintaining all the hardware, and you’re on the hook for keeping connectivity secure.
Since all LoRaWAN networks use the same frequencies, overlapping LoRaWAN networks and other networks on the same frequency band can interfere with each other and present IoT security challenges.
Open source technology
Compared to the proprietary Chip, LoRaWAN software is open source, which means it’s easy to develop your own LoRaWAN solutions, and there are numerous vendors that sell the network components like servers and gateways, all of which are interoperable.
Good coverage
LoRaWAN works exceptionally well indoors, though how well depends on the location. It uses sub 1GHz frequencies and a very narrow frequency band, which gives it good coverage and indoor penetration.
LoRaWAN is also useful because you can get coverage pretty much anywhere in the world—so long as there’s either a service provider with infrastructure in place, or you deploy the infrastructure yourself. In most cases, you’ll need to build your own LoRaWAN network to ensure the sensors can be connected.
Low power consumption
LoRaWAN allows connected devices to “sleep” when they aren’t actively transmitting or listening for a signal. Additionally, transmitting or receiving a signal over LoRaWAN requires less than 50 milliamps (mA) of current. This means manufacturers can expect their devices to have up to 10 years of battery life.
Problems with LoRaWAN
Despite its strengths, LoRaWAN has a couple serious drawbacks as well. For many manufacturers, the challenges of LoRaWAN prevent it from being a viable solution.
Lack of network infrastructure
With cellular IoT, you can deploy anywhere in the world and find a carrier with coverage. The infrastructure is already in place before you deploy. But that’s not usually the case with LoRaWAN. Parts of the world have multiple LoRaWAN service providers. But many countries, regions, or cities have none. If you want to deploy in an area where there’s no LoRaWAN infrastructure, you have to build it yourself.
LoRaWAN is ideal for extending coverage to locations where there are no other connectivity solutions in place, such as specific buildings or isolated locations. It can also be a viable alternative to Wireless MBus, Wifi, or Bluetooth.
The low overhead of LoRaWAN (due to unlicensed bands) is often outweighed by the significant investment you have to make in development. And if you have to build your own infrastructure, you have to maintain it, too. (Not to mention, you’re responsible for keeping it secure.) Every time you deploy to a new region that doesn’t have LoRaWAN infrastructure, you have to build more.
No roaming agreements
While LoRa service providers can offer access to LoRa gateways that have already been deployed, these providers don’t have roaming agreements with each other. This means deploying in new regions will require you to either add a contract with another provider or build your own LoRaWAN to cover the new area. Using a different solution for every deployment can make managing your connectivity a logistical nightmare.
Extremely limited messaging capabilities
LoRaWAN networks can facilitate IoT communications. But they can’t handle very much communication. In fact, with LoRaWAN, you can only send a limited number of messages per day. To keep frequencies from becoming overcrowded, some governments have implemented duty cycles. They may only allow a device to use the frequency band as little as 1% of the time.
Additionally, LoRaWAN allows all your connected devices to transmit whenever they need to. The more devices you have connected at once, the greater the chance that they’ll transmit at the same time and interfere with each other. LoRaWAN often produces Packet Error Rates (PERs) of more than 50%. A higher PER increases the duration of transmissions and makes power consumption harder to predict. If your application requires a low PER (many applications require a PER of 0%), then this won’t work for you.
LoRaWAN gateways can’t transmit and receive at the same time. So if your application requires message receipts (to ensure the data is correctly delivered) and your devices transmit often, it can make your gateways unavailable frequently. LoRaWAN won’t provide message receipts unless the nodes ask for them, and sending firmware updates to your device to fix bugs or vulnerabilities will make them unavailable. This forces you to choose between service disruptions and security.
Get connected with emnify
LoRaWAN makes sense for some applications. If you need to connect multiple sensors to a single gateway, you wouldn’t want to install SIM cards on every sensor. But for the gateway to the network server, cellular connectivity is a much better solution.
And for a deployment of a single device, you wouldn’t want to deploy a LoRa gateway, and there often isn’t a LoRa provider available where you need them. Cellular connectivity is already available anywhere in the world, and technology like LTE-M and NB-IoT have similar power consumption to LoRa.
Cellular networks offer good indoor coverage and work exceptionally well with mobile applications. With emnify’s IoT communication platform, managing your connectivity is simple, intuitive, and cost effective.
