LoRaWAN is a low-power wide-area network (LPWAN) protocol for battery-powered sensors and meters that send small amounts of data over long distances. A device sends each reading as a short radio packet in an unlicensed sub-GHz band. Every LoRaWAN gateway in range receives it and forwards it over IP to a network server, which checks it, removes duplicates and passes the decrypted data to an application. Typical links reach a few kilometres in towns and further over open ground, at a few hundred bits to a few kilobits per second, and a device can run for years on one battery. The LoRa Alliance publishes the specification, which ITU-T also adopted as Recommendation Y.4480.
LoRaWAN at a glance
| LoRaWAN | |
|---|---|
| Radio | LoRa chirp spread spectrum, unlicensed sub-GHz bands |
| Frequencies | 863 to 870 MHz in Europe (EU868), 902 to 928 MHz in North America (US915), other plans by country |
| Data rate | 250 bit/s to 5.5 kbit/s on 125 kHz channels in EU868 |
| Payload | 51 bytes per uplink at the slowest data rate in EU868, up to 222 bytes at the fastest |
| Range | Hundreds of metres indoors, kilometres outdoors, depending on the antennas and terrain |
| Topology | Star of stars: devices to gateways, gateways to one network server |
| Security | AES-128: one key for integrity on the network, a separate key for the application payload |
| Battery life | Years, depending on the reporting interval and the spreading factor |
| Who runs it | You (a private network) or a public network operator |
LoRa and LoRaWAN are not the same thing
LoRa is the radio modulation, developed by Semtech. It spreads each symbol across a 125 kHz or wider channel as a chirp, which lets a receiver decode signals far below the noise floor. The spreading factor (SF7 to SF12) sets how long each symbol lasts: a higher SF is slower but reaches further.
LoRaWAN is the network protocol on top of it, published by the LoRa Alliance. It defines how devices join, how frames are addressed and encrypted, when a device may receive, and how the network server manages data rates. A radio module or a sensor that "uses LoRa" can run a proprietary point-to-point protocol instead, and no LoRaWAN network will receive it. Check that a device is LoRaWAN-certified or at least states its LoRaWAN version and regional plan.
How a LoRaWAN network works
| Part | What it does |
|---|---|
| End device | A sensor or meter interface with a LoRa radio. It sends uplinks when it has data and listens for downlinks at fixed times |
| Gateway | Receives every LoRa packet it can hear on its channels and forwards it over Ethernet or cellular to the network server. It does not decode the payload |
| Network server | Removes duplicates received by several gateways, checks the frame counter and integrity code, manages data rates and schedules downlinks |
| Join server | Holds each device's root key and handles the join, so the network server never sees the application key |
| Application server | Decrypts the payload and runs the device's payload decoder, which turns bytes into named values with units |
Devices do not relay for each other and are not tied to one gateway. A reading that three gateways hear reaches the network server three times, which keeps one gateway failure from losing data. Gateways forward to the network server with Semtech's UDP packet forwarder or with LoRa Basics Station over a secure WebSocket.
The network server is the part people forget. Every deployment needs one: a public network's, a cloud service, or one run on site. The device keys, the decoders and the integrations that deliver data onward all live there, so agree early who owns it.
Device classes
| Class | When the device can receive | Typical device |
|---|---|---|
| A | Only in two short windows after each of its own uplinks | Battery sensors and meter readers: every device supports Class A |
| B | Also in scheduled slots, synchronised by beacons from the gateways | Battery actuators that need commands within minutes |
| C | Almost all the time, except while transmitting | Mains-powered relays and controllers |
A command to a Class A meter that reports every hour can wait up to an hour. The Zigbee vs LoRaWAN guide covers downlinks, confirmed uplinks and the failure modes that matter on site.
Joining and security
A device joins by over-the-air activation (OTAA): it sends a join request with its DevEUI and JoinEUI, and the join server answers with session keys derived from the device's root key (AppKey). Activation by personalisation (ABP) skips the join and stores fixed session keys in the device. Prefer OTAA, because a device that resets its frame counter under ABP is ignored by the network server until the counter passes its old value.
Each frame carries an integrity code computed with the network session key and a payload encrypted with the application session key. The network operator can therefore route a reading without being able to read it. Keep the AppKeys in a key store, not in a spreadsheet sent by email.
Frequency plans by region
The LoRa Alliance regional parameters set the channels, data rates and power limits for each region, and local radio rules add their own limits:
| Plan | Band | Where | Main constraint |
|---|---|---|---|
| EU868 | 863 to 870 MHz | Europe, and many other countries | Duty cycle, 1% in the default 868.0 to 868.6 MHz sub-band |
| US915 | 902 to 928 MHz | United States, Canada | 400 ms dwell time, so uplinks use SF7 to SF10 only |
| AU915 | 915 to 928 MHz | Australia | Like US915, but uplinks may use SF12 (DR0) under the current regional parameters; the 400 ms dwell limit applies only when the network signals it |
| AS923 | 915 to 928 MHz, varies | Much of Asia | Country-specific sub-bands and dwell time |
| IN865 | 865 to 867 MHz | India | Three default channels |
A device is built for one plan. Order it for the country where it will be installed, and check that the gateway and the network server use the same plan and, in US915, the same sub-band of eight channels.
Spreading factor, airtime and range
The SF sets a trade-off between range and airtime. For a 12-byte reading (25 bytes on air with the LoRaWAN header) on a 125 kHz channel:
| Spreading factor | Time on air | Shortest gap at 1% duty cycle |
|---|---|---|
| SF7 | 62 ms | 6 s |
| SF9 | 206 ms | 21 s |
| SF10 | 412 ms | 41 s |
| SF12 | 1,483 ms | 148 s |
SF12 takes 24 times the airtime of SF7, and the battery pays for every millisecond. Adaptive data rate (ADR) lets the network server move a device with a strong signal to a lower SF and less transmit power, which saves battery and leaves the channel free for others. A device in a basement may only link at SF12, so plan its reporting interval and battery life on that figure, not on the datasheet's best case.
Range comes from the link budget: transmit power, antenna gains, cable losses and the receiver sensitivity at the chosen SF, against the path loss of the site. A gateway antenna above the roofline matters more than any setting. Model the link with the wireless link budget calculator, check the Fresnel zone clearance for a long outdoor hop, then confirm with a test device at the real meter positions.
LoRaWAN vs NB-IoT, LTE-M and other LPWAN networks
| LoRaWAN | NB-IoT | LTE-M | Sigfox | Wireless M-Bus | |
|---|---|---|---|---|---|
| Spectrum | Unlicensed sub-GHz | Licensed mobile bands | Licensed mobile bands | Unlicensed sub-GHz | Unlicensed, 868 MHz in Europe |
| Network | Your gateways or a public operator | Mobile operator | Mobile operator | Sigfox network operator | Your receivers, walk-by or drive-by reading |
| SIM or subscription | No SIM; a network server | SIM per device | SIM per device | Subscription per device | None |
| Data | Small, 51 to 222 bytes per uplink | Larger messages, higher rates | Up to about 1 Mbit/s, voice and mobility | 12 bytes per uplink, up to 140 a day | Meter telegrams |
| Indoor and below-ground reach | Good, and you can add a gateway | Good where the operator covers it | Less than NB-IoT | Good where covered | Short range |
| Typical use | Private sites, campuses, utilities | National fleets of fixed devices | Trackers, devices that move | Simple alarms and counters | Water and heat meter reading |
The decision is usually about who owns the network. LoRaWAN lets a site or an estate run its own coverage with no per-device SIM. NB-IoT and LTE-M rely on an operator's coverage and pricing but need no gateways. Wireless M-Bus (EN 13757-4) is common inside water and heat meters themselves and is read by its own receivers. For a comparison with short-range mesh networks inside buildings, see what is Zigbee.
LoRaWAN for metering
On energy and building projects, LoRaWAN devices are mostly retrofit readers: a pulse counter on a water or gas meter, a current sensor on a cable, a temperature sensor in a cold room. Choose devices that send a cumulative register, such as total m³ or total kWh, in every uplink. A lost uplink then costs time resolution, not consumption. The pulse meter guide explains how to wire a pulse reader to a meter.
Before rolling out, check each device's regional plan, LoRaWAN version and class, its payload decoder, the reporting interval at the SF it actually achieves, and who holds the device keys.
LoRaWAN with EpiSensor
Edge on the ZGW-20 Gateway reads the decoded uplinks of third-party LoRaWAN devices from the site's LoRaWAN network server and stores them beside Zigbee, Modbus and BACnet readings. The LoRaWAN device list shows how each model connects to Edge and which fields its decoder provides.
Common questions
What is LoRaWAN used for?
LoRaWAN carries small, infrequent readings from battery devices over long distances: water, gas and heat meter pulses, temperature and humidity, current clamps, occupancy, levels and alarms. It suits sites where devices are spread out, behind walls or below ground, and where running cables or a mesh network would cost more than the data is worth.
What is the difference between LoRa and LoRaWAN?
LoRa is the physical layer: a chirp spread spectrum modulation from Semtech that trades data rate for range. LoRaWAN is the medium access and network protocol published by the LoRa Alliance: device addressing, joining, encryption, device classes and how gateways and the network server work together. LoRaWAN uses LoRa, but LoRa can also be used without LoRaWAN, in point-to-point links that no LoRaWAN network can receive.
What is the range of LoRaWAN?
In practice, a few hundred metres through buildings and basements, two to five kilometres in towns, and ten kilometres or more across open ground from a gateway on a mast. Range depends on the spreading factor, antenna height, terrain and walls more than on the protocol. Measure it with a test device at the real installation points.
What frequency does LoRaWAN use?
LoRaWAN uses unlicensed sub-GHz bands defined per region by the LoRa Alliance regional parameters: 863 to 870 MHz in Europe (EU868), 902 to 928 MHz in North America (US915), 915 to 928 MHz in Australia (AU915), 865 to 867 MHz in India (IN865) and AS923 in much of Asia. A device must match the plan of its network.
Is LoRaWAN better than NB-IoT?
Neither is better in general. LoRaWAN runs in unlicensed spectrum on gateways you can own, with no SIM or operator, which suits private sites and basements reached by your own gateway. NB-IoT runs on a mobile operator's licensed network with a SIM per device, which suits devices spread across a country where the operator already has coverage.
Does LoRaWAN need the internet?
No. The gateways need an IP connection to the network server, but the network server can run on site, on the same local network. Only a public network, or a network server in the cloud, needs an internet connection.