LoRaWAN Explained
- News
- 23 Feb, 2023
Sound confusing? Don’t worry, you’re not alone! In this article we will sort out what LoRa “things” are, how they are linked, and what they’re for.
Why Is LoRa and LoRaWAN important?
To understand this, we need to know a bit about networks first. Anything connected to the internet, or any devices connected to each other, is a part of a network. A network can be small and private, or huge like the internet. There are two main types of networks in IT or computer terms: a LAN and a WAN.
A LAN, or Local Area Network, is a network that is formed when multiple devices such as smart TVs, routers, tablets, and computers are connected to each other. This type of network is typically small and private, not accessible from the outside internet, and can include both wired and wireless connections. LANs connect devices that are situated within a single limited area.
On the other hand, a WAN, or Wide Area Network, is a much larger network that is not confined to a single location. These networks can be global in scale and are typically provided by WAN providers. The internet is considered the world's largest WAN. WANs play a vital role in keeping companies and international businesses connected, and are also widely used in everyday applications. Essentially, WANs are telecommunication networks that allow devices to communicate with each other and transfer data from all corners of the world.
Here are three types of networks currently used for IoT:
LAN. Short Range, Unlicensed
IoT LANs are usually Bluetooth or WiFi, and are the most common internet networks. As with any LAN, IoT LANs have several drawbacks, the primary among them is you need to be close to a router or attached to a cable.
Best for:
- Short-range communications
- High data-rate transmissions like streaming and gaming
Weaknesses:
- High power use because of high data transfer
- Short range
- Doesn't travel far, easily impeded
LPWAN, Long Range, Licensed
Licensed LPWAN is a Low Power Wide Area Network that operates on LTE-based cellular frequencies within the licensed radio spectrum. In South Africa, these frequencies are allocated by the Independent Communications Authority of South Africa (ICASA) and are owned by cellular network providers such as MTN, Vodacom, and Telkom. These providers have acquired their portions of the cellular frequency spectrum for substantial amounts of money and, as a result, charge users to access and use these frequencies. Unlike LoRa, which is a free-to-use network solution, licensed LPWAN is not free as it operates on these owned frequencies. If you have multiple devices on the network utilizing bandwidth, the costs can quickly accumulate.
Best for:
- Long-range communications
- High data-rate IoT transmissions like smart cities
- Advanced properties for higher-need applications like VoLTE
- Good indoors and in built-up urban areas
Weaknesses:
- Uses lots of battery power, especially when using high data rates or continuously on
- Costly to run
- Includes monthly subscription fees
- Will only work where you get an LTE signal
LPWAN Unlicenced (or LoRa!) Long Range, Unlicensed
Unlicenced LPWAN uses frequencies that are unlicenced and free to use across the world. Because of this devices do not have to pay to communicate on them. These frequencies are globally unlicenced and allow connected IoT devices to roam locally and internationally while still staying connected to its chosen frequency.
Great for:
- Short range to over 10 miles
- Incredible battery life, up to 10 to 15 years
- Few setup and implementation costs
- Easy to increase capacity
- Can be used for public or private networks
- Low frequency for great building and underground penetration
- Supports roaming, and firmware updates over the air (FUOTA)
- Bi-directional communication (Full Duplex capability)
Less Effective For:
- High data-rate transmissions
If you have an IoT network, you need to use one of these three options. The first is not suitable for long-distance applications, and the second can end up costing a boatload of money. So that leaves unlicensed LPWAN, or LoRa.
LoRa vs LoRaWAN
LoRa and LoRaWAN are not the same things. LoRa is a radio modulation that gets data through the air over long distances. It's a radio wave system that allows devices to talk to other faraway devices without using much power. When we say less, we mean way less. Less than WiFi, less than 5G, less even than LTE or Bluetooth. This means that batteries on connected devices could potentially last for years.
You can run sensors on a regular AAA battery for months and months. This is particularly useful for agriculture, unmanned stations, or even monitoring things like earth disruptions. More on that later.
LoRa is one of the most popular technologies in LPWAN (Low Power WAN) communication. There are several of them out there, but LoRa is fast becoming the leader of the pack for various reasons. Its ultra-long distance abilities are based on frequency modulation spread spectrum technology. It takes into consideration both distance and power, finding the perfect balance between the two. LoRa network frequency bands are 433 HZ, 868 HZ, and 915 HZ, which are globally recognized as free.
LoRa devices connect to each other, to gateways, and to the internet via radio waves. No SIM card, no WiFi, just their own network needed. That network is LoRaWAN.
LoRaWAN is created when these devices are joined together. A LoRaWAN can be small and private with only a few local sensors or satellites linked to one or two gateways, or it can be regional with satellite devices being linked to multiple gateways which are then linked to a server. There is also a global network where sensors or nodes are linked to gateways across the world, which in turn are all linked to one server.
There is no actual internet in the LoRaWAN, except when your gateway connects to the internet. That is great news for security. You build your own private LoRa network wherever you need one, and then link it to the cloud or a server via an internet connection.
There are three types of LoRaWAN: Public, private, and hybrid.
Public LoRaWAN: Globally there are several active LoRaWAN networks that you can connect to. Most countries are a part of it and have gateways all over their cities, and sometimes in the country as well. If you have a herd of cows with sensors, and you want to keep an eye on them but don't want to set up your own LoRaWAN network, you can connect to one of the public options. Like cellular, there are many network providers.
Private LoRaWAN: A private LoRaWAN is a self-contained network that you can create. If you have a herd of cows, you can put a sensor on each cow, link them to a gateway, and then link the gateway to a private server. This is like CBRS cellular radio systems. You don't have a limit to the number of devices or nodes you can connect, or the number of gateways you can add. This means that theoretically, you could create a huge, global private IoT network connected to your personal server, with the highest level of security.
Hybrid LoRaWAN: A hybrid network could consist of lots of nodes connected either to your private network, or a public one. Because LoRa supports roaming, your nodes could reconnect with a public gateway when they are out of range of your private ones.
What does all that mean?
Simply put, WiFi and Bluetooth are approaching end of life. Well, eventually. Their networks require lots of power and often provide more bandwidth than the device needs. Some IoT and M2M devices don’t need to communicate lots of data. Imagine a network, separate from the internet and outside networks, that uses very little power, is global, and affordable. That’s LoRaWAN.
Who Regulates LoRaWAN?
LoRaWAN is managed by the LoRa Alliance. This is an open-source, non-profit organization whose sole purpose is to promote LoRa and LoRaWAN made up of IT developers. They have created their own global ecosystem of device makers, solution providers, system integrators, and network operators, which is free to join for anyone.
The LoRaWAN Alliance wants to make LoRa the main LPWAN (Low Power WAN) of choice across the world. Currently, the global LoRa ecosystem consists of about 18 million gateways. The idea behind the movement is to grow a worldwide wireless network that anyone can connect their IoT sensors to, without massive cellular or WiFi charges.
“With LoRaWAN®, entire cities or countries can be covered with a few base stations, no longer requiring the upfront rollout and maintenance of nodes as in traditional mesh networking.”
Olivier Hersent - Chairman & CTO, Actility
How Does LoRaWAN Work?
To understand how the magic happens you need to know what Chirp Spread Spectrum (CSS) modulation is. This is a complicated radio modulation technique, so we’ll simplify it for you.
Wikipedia says: “In digital communications, chirp spread spectrum (CSS) is a spread spectrum technique that uses wideband linear frequency modulated chirp pulses to encode information. A chirp is a sinusoidal signal whose frequency increases or decreases over time (often with a polynomial expression for the relationship between time and frequency).”
A “chirp” is a kind of quick radio wave that uses its whole bandwidth to transfer data. This makes it "robust”. I.e.it can stand up to signal noise really well.
Let's say you're sitting in a restaurant, conversing with another person amidst some background noise. As time goes on, the noise level increases, making it increasingly difficult to communicate effectively. Eventually, the noise level reaches a point where you can no longer hear what the other person is saying, despite being able to see their lips moving. This is what's known as channel noise, and it can lead to data transfer breakdown in most radio communication scenarios.
However, with the chirp technique employed by LoRa devices, they can still communicate despite the presence of channel noise. This is akin to reading lips in a noisy environment - even if you can't hear what's being said, you can still interpret the message through visual cues.
Chirp is also resistant to multipath fading. That’s where a signal bounces off many things like walls, all at the same time. The receiving device gets repeats of the same message, which can cause the signal to weaken. It's also resistant to the Doppler effect. This is all really useful if you need to send data across challenging environments, like deep into the earth.
LoRaWAN uses chirp protocol to send packets of data. These packets hold all the info that is needed to get the message across. Often parts of these packets get lost due to channel noise, signal loss, or multipath fading. LoRa expects package loss and can still receive the entire message with up to 30% interference.
Advantages and Disadvantages of LoRa WAN
- LoRaWAN operates on globally available 868 MHz/915 MHz ISM bands and is free to use, making it accessible worldwide.
- Coverage range is over 4.8 kilometers in urban areas and over 14.5 kilometers in suburban areas.
- Highly energy-efficient, allowing batteries to last for years without replacement A single LoRa gateway can connect to thousands of end nodes or sensors, making it highly scalable.
- Adaptive Data Rate technique improves the capacity of the entire LoRaWAN network, varying the output data rate of nodes and sensors between 0.3 kbps to 27 Kbps for 125 kHz bandwidth.
- LoRaWAN is an increasingly popular choice for IoT and M2M applications.
- Supports a larger payload size of up to 100 bytes compared to SigFox's 12 bytes Open source and open standard.
- No limit on the number of messages that can be sent per day Ideal for smart city applications due to long-range capabilities.
- Low-bandwidth option for IoT applications that don't require high bandwidth.
- Lower connectivity costs than other IoT network solutions High level of security for data transmission Enables bidirectional communication Users can choose from three different classes depending on their specific needs.
Disadvantages of LoRaWAN
- It's only really for low data applications, up to 27 Kbps
- It's not good for applications that cannot handle latency or jitter. For that have a look at our SD WAN article.
LoRaWAN Architecture
A LoRaWAN consists of three main elements: the node or sensor, the gateway and the end server. You must buy gateways and nodes, but you can use a cloud-based server like AWS
- Nodes or sensors. These are the working bits of the LoRaWAN network. They can be used for a range of applications, from monitoring where something is, to recording freefall, to location tracing, temperature tracking, the IoT applications are endless. Nodes are usually quite small and able to be inserted into things like ear tags, packing crates, or ground sensors.
- Gateways. The node then communicates with a gateway, which is linked to the LoRaWAN network. Gateways are like routers and are made by various people. For instance, Peplink make a router that has LoRa gateway capability. Interestingly, gateways don't actually DO anything, they just relay messages from the server to the node. They are a collective point for data though and can communicate with many nodes at the same time.
- Network server. The final piece is the network server. This could be in the cloud, or in an end terminal like a head office. You can get a LoRa server from service providers like Amazon Web Service or buy the hardware and software and build your own. LoRaWAN servers exist all around the world. If a node travels and loses contact with one network, it can reconnect to another, much like your phone does when roaming.
Node Settings
In your LoRaWAN you have three choices of terminal equipment, or node settings.
- A or Aloha. In this setting a node wakes up only when it needs to send a message via the gateway to the network. It can remain in sleep mode for as long as it has nothing “to say”. This is the best setting to save battery as it only uses power when it wakes up. The drawback to this is that if the network has a message to send, it can only do so when the node wakes up. This could take a long time.
- B or Beacon. In this setting a node wakes up every so often and checks in with the network. Think of a lighthouse, which is a sort of beacon, hence the name. A pulse is sent out usually every 128 seconds. If neither the gateway nor the node has a message the node goes back to sleep. This pulse lasts a split second. If a message needs to be either sent or received by the node, then they will happen consecutively a second after each other. The node will then go back to sleep until the next interval.
- C or Continuous. Class C terminal devices are only good if you have a continual power source. The terminal or node is constantly listening to the network and never sleeps. This way it can receive a message at all times and can also send a message at any time. Because it never sleeps, the node uses much more power than class A or B. the only time that it cannot receive a message is when it is busy transmitting.
LoRa Class A | LoRa Class B | LoRa Class C |
Battery Powered | Low Latency | No Latency |
Bidirectional communications | Bidirectional with scheduled receive slots | Bidirectional communications |
Small payloads, long time between communication | Small payloads, long gaps, receives regular signal from gateway | Small payloads |
End-device begins uplink communication | End device begins uplink and has extra receiving slot | Server can begin communication at any time |
End device only communicates with server during set receiving time | Server can begin downlink at fixed intervals | End-device is always listening or receiving |
Each node can be one of these three most of the time but can also be set to change terminal settings in an emergency. For example, if you have a sensor in the ground to measure seismic activity, it only needs to communicate when an abnormal measurement is detected. Most of the time it can be in Class A. During an earthquake it needs to be constantly online, so can be switched to Class C. Once the crisis is over, it goes back to being class A, and sleeping most of the time to conserve battery.
LoRa WAN Security Protocols
Since LoRaWAN is created for mass IoT, security is top of mind. Every node and gateway is equipped with mutual endpoint and data origin authentication. This means that every device on the LoRaWAN continuously must prove who they are and that they are legit. Data is end-to-end encrypted using industry-standard AES 128. That's like the encryption that banks use. The software and firmware are constantly being updated remotely too, so the entire network gets a security makeover to make sure that protocols are always changing.
The security layers in LoRa are built into the actual protocol. It's not like WiFi where you must add a layer from an app like Windows Defender. The entire system is designed to be secure, which makes it very hard for hackers to break into. It is worth noting that for any LoRaWAN to be secure, it must be implemented correctly and with security as a priority.
The LoRa Alliance has a robust global device certification standard that devices must meet to even be a part of the LoRa world. If you find a device on the LoRa network that doesn't have the LoRaWAN mark, then it likely isn't certified.
What Is LoRaWAN Used For?
This is where things get interesting. LoRa is a real option for long-term communication. It's cheap, secure, and able to be implemented easily and affordably. It can also be used in conjunction with cellular. So, if you have a situation where you need high data transfer and low data transfer you can use both.
Imagine you have a herd of cows. Each cow has a monitor linked to your private LoRaWAN. However, there is also a camera in their barn that is linked to an app via a 4G or LTE connection. Your app will not only show the camera view, but also allow you to see each cow’s current vital statistics. Temperature, heart rate, whatever you like.
Each class or LoRa end device can be used in different situations. For instance, class A or Aloha is perfect for smart water meters, or anything that needs to report a status a few times a day. A battery on one of these can last 10 to 15 years.
Class B can be used for a temperature sensor and meter that sends frequent reports on levels of moisture, temperature, and so on. This device can potentially turn valves on or off with some latency, and only requires a few uplinks and downlinks per day. Batteries on this device wouldn’t last as long.
Class C would be for any device that needs to send reports and carry out actions a few times a day, such as systems monitoring and adjustments. These devices would ideally have a permanent power source.
We previously touched on the three network possibilities of LoRa: public, private, and hybrid. Each of these could be used for any number of applications. The number of LoRa devices worldwide was estimated at a massive 571 million units in 2020 and will grow to 2.2 BILLION by 2025.
As 2G and 3G units that were deployed before LPWAN was popular get retired, they will likely be replaced with more affordable LPWAN options. This will equate for about 50% of the growth in LPWAN over the next few years.
LoRaWAN works on a flat monthly rate, per message, or gateway, or a combination of the three. If you have a private network you may be able to run it on little to no fees at all except initial set up. The potential for LoRa to become the main network system for all massive IoT is extraordinary.
Some examples include:
- Energy and utilities: metering, heating and grids
- Building automation: space optimisation, cleaning, worker and workplace safety, and temperature monitoring
- Supply chain: asset tracking, fleet management, cold chain monitoring, supply chain monitoring, and intralogistics
- Smart cities: lighting, waste management, parking, water management
- Agriculture: irrigation, soil moisture, animal husbandry, environment monitoring
- Industrial IoT: oil and gas, mining, production and manufacturing, predictive maintenance, valve monitoring
The potential for LoRa is immense. In time it will likely become as well known and widely used as cellular. IoT all over the world can connect to a safe, affordable system, either private, public, or both. Why would you choose to connect your IoT devices any other way?
At Bolton Technical, we offer only the best brands. Whether you are looking for a strong signal booster for your home, something to keep you connected on the road, or a good way to stay in touch out at your cabin, we have the answer. We specialize in custom-made, consumer-friendly kits, RF systems for cellular, public safety two-way radio, DAS, and WiFi. If you need info on anything 5G, 4G, LTE, cellular, LoRa, WiFi, how to boost your cell signal, don’t hesitate to contact us at 011 749 3085.