Four answers at different layers
These four names get lined up as rivals, but they do not describe the same kind of thing. Each answers a different question in the stack.
- Bluetooth LE is a complete radio system, from the radio itself up to how devices advertise, connect and exchange data. The Bluetooth SIG lists point-to-point, broadcast and mesh among the topologies it supports. How Bluetooth Low Energy works covers the stack.
- Thread is a network layer. OpenThread describes it as an IPv6-based networking protocol for low-power Internet of Things devices in an IEEE 802.15.4 wireless mesh. It moves IP packets and, as the Thread Group puts it, is not restricted to one set of applications, so the application language comes from above, for example Matter.
- Zigbee is a full stack on the same IEEE 802.15.4 radio, including its own application layer, which the Connectivity Standards Alliance calls the language that lets smart objects work together.
- LoRa is only the physical layer. The LoRa Alliance defines LoRa as the physical layer, using Chirp Spread Spectrum modulation, and LoRaWAN as the network protocol at the MAC layer.
That last point matters most when comparing. “LoRa vs Thread” is really “a radio vs a network”. The fair comparisons are LoRaWAN or a LoRa mesh against Thread or Zigbee.
Side by side
| Bluetooth LE | Thread | Zigbee | LoRa | |
|---|---|---|---|---|
| What it defines | Radio and full protocol stack | IPv6 mesh network over 802.15.4 | Mesh network and application layer over 802.15.4 | Radio modulation only |
| Band, per its own body | 2.4 GHz ISM band, 40 channels | 802.15.4 on the 2.4 GHz spectrum | 2.4 GHz worldwide, 915 MHz in the Americas, 868 MHz in Europe | Unlicensed ISM bands |
| Network shape | Point-to-point, broadcast or mesh | Self-healing mesh | Self-healing mesh | Set by what runs on it: star-of-stars in LoRaWAN, a mesh in Meshtastic |
| Security | Pairing and link encryption in the stack (details) | All devices authenticated, all communications encrypted | AES-128 message encryption and authentication | None in LoRa itself; LoRaWAN adds it |
Bluetooth LE: the radio phones already have
The Bluetooth SIG’s overview puts Bluetooth LE in the 2.4 GHz ISM band with 40 channels at 2 MHz spacing, three of them for advertising. Its data rate depends on the physical layer chosen: 2 Mb/s on LE 2M, 1 Mb/s on LE 1M, and 500 kb/s or 125 kb/s on LE Coded, which trades speed for range.
Its distinguishing feature for builders is reach into phones. Android’s documentation describes built-in platform support for Bluetooth LE, so a phone app can use it as a node with no extra hardware. That is why phone-to-phone meshes use it, and why Zigbee added Zigbee Direct, which the Alliance describes as bringing together Zigbee and Bluetooth Low Energy to simplify the user experience. The SIG’s own mesh standard is a separate thing again, covered in how Bluetooth Mesh works.
Thread and Zigbee: same radio, different stacks
Thread and Zigbee both build on IEEE 802.15.4, the low-power radio standard that both bodies cite. The Connectivity Standards Alliance gives Zigbee raw throughput of 250 kb/s at 2.4 GHz across 16 channels, and transmission distances of 10 to 100 metres depending on power and environment, with 1 km or more possible on its sub-GHz radios.
The difference is what sits above the radio. Thread carries IPv6, and a Thread Border Router, in OpenThread’s description, connects the Thread network to other IP networks such as Wi-Fi or Ethernet. OpenThread lists self-healing routing with no single point of failure, sleepy battery devices, and networks of up to hundreds of devices. Zigbee defines its own network and application layers, and the Alliance’s certification covers every layer of the stack, so certified products from different makers are meant to work together.
LoRa: range in exchange for data rate
LoRa trades speed for distance. The LoRa Alliance describes LoRaWAN’s long-range capability as up to 15 km in rural areas, operating in unlicensed bands. The cost is data rate and airtime, and in some regions duty cycle limits cap how often a device may transmit. LoRaWAN suits sensors that report a small reading now and then.
What runs on the radio decides the network. LoRaWAN uses a star-of-stars: devices reach gateways in one hop, and gateways forward to a network server over IP. Mesh networking vs LoRaWAN compares that with a mesh, and Meshtastic is an open-source mesh built on LoRa radios.
How to choose
A few questions settle it quicker than spec sheets.
- Does a phone need to be a node? Then Bluetooth LE, the radio phone apps can reach directly.
- Is it a home or building product? Thread, under Matter, or Zigbee. Pick the one your target ecosystem certifies.
- Do readings need to cross kilometres on a battery? LoRa, with LoRaWAN if someone runs gateways and a network server, or a LoRa mesh if devices must talk to each other.
- How much data moves? Bluetooth LE’s published rates, up to 2 Mb/s, are well above Zigbee’s 250 kb/s, and LoRa gives up rate for range.
A single design can combine them: a sensor on Thread or LoRa, a gateway that bridges to IP, and a phone that configures it over Bluetooth LE.