What is LoRaWAN?
LoRaWAN is a proprietary LPWAN-connectivity protocol developed by Semtech. It is renowned for its low power usage and high transmission range (even when compared to other LPWANs). Also, it has a high resistance to interference, as its wireless modulation is based on technology developed for the military and space industry. In 2017 a LoRaWAN packet was transmitted over a distance of 702km, breaking previous records. These unique characteristics make it the ideal connectivity protocol for a variety of IoT use cases. LoRaWAN is maintained by the LoRa alliance, an open, non-profit association. Its members include certified device manufacturers, service providers, and public institutions.
The difference between LoRa and LoRaWAN
Both LoRa and LoRaWAN are often confused with one another; while both must be utilized to benefit from their unique connectivity solution, these terms shouldn’t be used interchangeably.
LoRa itself represents the physical layer of the network technology; it powers the wireless modulation, which is used to establish a long-range communication between devices. Most wireless systems use a traditional modulation, such as frequency key shifting (FSK). However, LoRa relies on a modulation called CSS (chirp spread spectrum) modulation, which has been developed by the military and space industry with the goal of creating an LPWAN, that is extremely long-range and resistant to interference. While CSS and FSK both feature low power consumption, CSS drastically elevates the communication range capabilities of its devices.
LoRa can be considered a proprietary derivative of CSS, allowing the operator of an IoT network to trade data rate for more range or power to optimize their network’s performance based on their requirements.
How LoRaWAN works
Networks are typically deployed using a mesh network architecture. It is for example the case for the Zigbee communication protocol, used by the Philips Hue lighting solution. In this architecture type, the end-nodes (in IoT: the sensors, actors, etc.) relay information to other nodes (gateways), thus increasing the communication range. However, this architecture comes with numerous tradeoffs, such as less capacity, shorter battery life (nodes need to both send and receive data), and a more complex network map (which can lead to maintenance and troubleshooting being labor-intensive).
LoRaWAN uses a “star”-shaped architecture, which means gateways are not always assigned specific nodes. Instead, data broadcast by a node is received by multiple gateways. Each of these gateways will relay the data packet to the network server without pre-processing said data. In other words: all the complexity of removing duplicate data packets, verifying data integrity, and performing security checked is pushed to the network server (which typically isn’t limited on power). In addition to that, nodes in the star-architecture do not need to listen for messages from other nodes continuously and can remain in sleep mode for most of the time, hence reducing their energy consumption.
Public LoRaWAN networks
Public LoRaWAN is typically deployed by phone operators/communication providers. These providers will leverage their existing infrastructure and customer base to offer their own LoRaWAN network and sell network access in a subscription-based model, as they do with other communication protocols. The network is more or less available to users on a national level, and IoT companies may decide to subscribe to the service if deemed viable. In Switzerland for example, the national telecom company Swisscom deployed a nationwide LoRaWAN network to support the creation of low-power smart solutions.
Community-based LoRaWAN networks
Community networks are usually supported by individuals, such as hobbyists, non-profit organizations and small businesses. A popular example is given by The Things Network which offers a LoRaWAN network server infrastructure for a global community of users. The whole gateway infrastructure is then organically supported by the users of the network, who install the individual gateways when a better coverage in a specific area is needed.
Private LoRaWAN networks
These private networks are deployed with the purpose of serving a sole entity instead of serving multiple users. The user can customize the network to suit the needs of his/her own fleet of IoT-end devices. The private LoRaWAN network allows companies to connect their internal network to the IoT environment without having to rely on the internet. Loriot is an example of a private LoRaWAN server network that is used by a growing numbers of companies around the world to establish their own enterprise-grade LoRaWAN deployments.
The fastest and easiest way to get started with an IoT project based on LoRaWAN is to use the connectivity-as-a-service offering of state-of-the-art IoT platforms. In this case, one doesn't need to subscribe to a separate connectivity contract with any network operator. Instead, one can use the connectivity and network of choice directly in the IoT platform. That enables launching PoC projects without long-term contractual commitment, with monthly billing based on the connectivity usage (number of devices connected to the cloud).
What is a LoRaWAN gateway?
LoRa Gateways, such as the ones listed here, are a physical device that houses both hardware and firmware used to connect IoT end-device to the cloud, an integral task that forms the backbone of any functional LoRaWAN-based IoT network. The gateway is a centralized hub, where IoT sensors drop their gathered datasets to be relayed to the network server. The gateway receives RF signals sent by these end devices and then converts them to a signal that is compatible with the network server.
Limitations of LoRaWAN
LoRaWAN achieves lower power and long-range partly by sacrificing bandwidth. The use of license-free frequency bands (for example 868MHz in Europe) make it only possible to send uplinks and downlinks messages at predefined intervals, therefore not allowing a continuous flow of data. Thus LoRaWAN is only ideal for periodical communication and (if you want to save on battery) should mostly be used for uplink communication.
An additional limitation of LoRaWAN may be caused by the proprietary status of the LoRa modulation. Manufacturers that want to develop IoT devices based on their own chipset will need to license the IP from Semtech first.
LoRaWAN use cases
Numerous institutions and private companies that are LoRa alliance members are already invested in broad industries that have a high potential to benefit from a LoRa-powered IoT network, such as:
- Smart Homes
- Transportation & Logistics
- Smart Utilities
- Smart Environment & Agriculture
- Industrial IoT
- Smart Buildings / Facility Management
We have a prominent project of our own that fits within the last use case mentioned above:
Over the past years, ISS Switzerland and akenza have collaborated on several projects that allowed ISS to offer new digital services and intelligent solutions to their customers.
Sensors were installed to visualize office space occupancy in real-time 2D maps of individual floors to help employees navigate more efficiently around the building to find free workspaces. Besides gathering occupancy data, the end-devices also measured the air quality of each room, such as temperature, humidity, CO2 levels, etc. Especially since the COVID-19 outbreak, sufficient ventilation has proven to be a key factor in enabling a safe work environment. In case of poor air quality, akenza’s room management automatically triggers alerts, which could further be used to control window blinds or ventilation systems.
While being proprietary and thus less transparent than some other LPWANs, LoRa alliance members are continuously innovating to further reveal the actual applicability of LoRaWAN in a variety of industries. Even though LoRaWAN evidently does have limitations regarding downlink transmission, transmission intervals, latency and bandwidth, these were sacrifices necessary to achieve long-range and low-power.
There may be attractive benefits to setting up your private LoRaWAN networks, such as better customization options and potentially better security. However, particularly in countries where governments actively support the roll-out of new innovative connectivity protocols, public LoRaWAN networks may become a more viable option for small-scale IoT operations, who may want to save on initial deployment costs and benefit from the sheer convenience of utilizing existing infrastructure.