Network technologies

This is where most procurement debates happen, and they are usually the wrong debate. Range, power and data rate pull against each other, and no radio wins all three. Pick the one that matches the job, then let the platform absorb the difference.

Family	Technologies	Designed for
LPWAN	LoRaWAN	Long range and very low power, small payloads sent infrequently
Cellular IoT	NB-IoT, LTE-M	Wide coverage on existing networks, low power, no network to build
Cellular broadband	4G LTE, 5G	High data rates and low latency, mains-powered applications
LAN	WiFi, Ethernet	High throughput over short range, existing infrastructure
Short range	BLE	Very low power, small payloads, phone and gateway friendly
Mesh	ZigBee, Z-Wave, Matter	Devices relay for each other, extending range indoors
Building automation	BACnet, KNX, Modbus	Heating, ventilation, cooling and building systems
Industrial	Modbus, PROFINET	Robust real-time control on the factory floor

The four characteristics that decide it

• Range, from tens of metres for short-range and mesh technologies, to kilometres for LPWAN and cellular.
• Power, where LPWAN, cellular IoT and BLE support multi-year battery operation, while WiFi and cellular broadband generally require mains power.
• Data rate, which rises in the same order, from a few bytes per message on LPWAN to video on WiFi and 5G.
• Infrastructure, meaning whether you build the network yourself, use an operator's, or use what is already in the building.

A fifth consideration is who owns the network. A private LoRaWAN network is yours to run and to fix; an operator network is theirs, which removes work and adds a dependency. Both are legitimate, and the choice usually follows how critical the application is and how much of the estate you control.

LPWAN

Low-power wide-area networks trade data rate for range and battery life, and the trade is dramatic: kilometres of range and years of battery, in exchange for small payloads sent occasionally.

LoRaWAN is the dominant open example. It has an excellent link budget, works in unlicensed spectrum (868 MHz in the EU), and can be deployed privately or bought from an operator. It suits remote monitoring, smart cities, buildings, agriculture and industry, where small readings are sent every few minutes to a few times a day.

The characteristics to design around:

• Payloads are small, typically a few dozen bytes, so devices encode aggressively.
• Range depends heavily on topography and construction. Basements and interior rooms often need an additional indoor gateway. Placing devices near ventilation ducts and stairwells frequently gains several dB.
• Delivery is best-effort by default. Confirmed messages and retransmission are available where they are worth the battery.
• Duty-cycle rules on unlicensed spectrum limit how often a device may transmit.

The chain has four hops: the device broadcasts; every gateway in range receives it and forwards over IP; the network server deduplicates the copies and handles security and session; the platform receives the payload, usually over MQTT. Several gateways hearing the same transmission is normal and gives redundancy for free.

Note the encryption along the bottom of that diagram: each hop protects its own leg, rather than one key covering the whole path.

Cellular IoT: NB-IoT and LTE-M

NB-IoT and LTE-M (Cat-M1) are cellular technologies designed for IoT rather than for phones. They give wide coverage on a network that already exists, with low power consumption, and need no network build of your own beyond a SIM.

• NB-IoT is optimized for small payloads and infrequent reporting, with excellent building penetration, and is well suited to metering and static sensors.
• LTE-M supports moving devices and faster transfers, which suits trackers and anything that needs to hand over between cells.

Both are designed for building penetration, reaching indoors and into basements. Both involve an operator subscription, and both leave the protocol choice open, so devices may arrive over MQTT, CoAP, UDP or raw TCP. That freedom is useful and it is also work: the integration is less uniform than LoRaWAN, where the network server standardizes the handover.

The operator's APN server is the hand-off point. Everything to the left of it belongs to the mobile network; everything to the right is ordinary internet traffic.

Cellular broadband: 4G and 5G

4G LTE and 5G offer high data rates and low latency, which is what applications with large payloads or real-time requirements need: cameras, video, AI at the edge, vehicle systems and critical control.

The trade is power and cost. These radios expect mains power or regular charging, and subscriptions cost more than IoT-tier connectivity. At the highest 5G frequencies, range shortens considerably. 5G additionally supports very large device populations and network slicing for critical traffic.

LAN: WiFi and Ethernet

WiFi gives very high throughput and low latency indoors, using infrastructure most buildings already have. It expects mains power except for short duty cycles, has shorter range than cellular or LPWAN, and shares a crowded band in dense environments.

Ethernet remains the most reliable option wherever a cable can go, and is common for gateways, controllers and anything stationary that matters.

Short range: BLE

Bluetooth Low Energy is built for very low power and small payloads over short to medium range, in practice 100 to 200 metres outdoors with BLE 5.0 and considerably less through walls.

It is easy to integrate with phones and gateways, which makes it the usual choice for wearables, beacons, asset tags, locks and a large family of medical devices. BLE devices reach the internet through a gateway or a phone rather than directly.

Mesh: ZigBee, Z-Wave and Matter

Mesh protocols have devices relay for each other, so coverage grows as the network grows and a single obstruction stops mattering. Range per hop is short, typically 10 to 50 metres indoors, and data capacity is modest, which suits building and home automation well.

• ZigBee has a large ecosystem and shares the 2.4 GHz band.
• Z-Wave uses sub-GHz spectrum with a limited number of channels, and includes AES-128 S2 security.
• Matter is a newer application-layer standard designed to let devices from different ecosystems work together over WiFi, Ethernet and Thread.

All of them need a hub or gateway to reach the internet.

That gateway is what the local technologies have in common, whichever radio they use:

The gateway is also where the protocol changes. Whatever the device spoke locally, what leaves the gateway is MQTT, HTTP or CoAP over IP, which is why these technologies integrate the same way despite being very different radios.

Building automation and industrial protocols

BACnet, KNX, Modbus and PROFINET came first, and they still run much of what is installed in buildings and factories. They are robust, real-time and thoroughly proven.

They predate internet-era security models and were designed for isolated networks, so security is normally provided at the network level around them rather than inside the protocol. They are also where a great deal of existing, valuable data already sits. The most useful data in a building is often already there, in a system installed long before anyone said the word IoT.

Yggio treats all of these as first-class. Connectors cover LoRaWAN network servers, cellular and generic devices over MQTT, HTTP, CoAP and UDP, building and industrial systems, and hubs that bring in Z-Wave, ZigBee and Matter. A LoRaWAN server can be included where you want one. Whichever way the data arrives, it lands as the same kind of device, with the same fields, access rights and history. See Connectors.

Choosing between them

Work backwards from the application, not forwards from the technology:

1. How often does the value need to arrive, and how quickly after it changes?
2. How much data is that, per message and per day?
3. Is mains power available, or must it run for years on a battery?
4. Where is the device physically, and what is between it and the nearest infrastructure?
5. Who will own and maintain the network?

The answers usually leave one or two candidates, and the rest of the argument is cost and coverage.