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Which link fits your product?

Describe what your product has to do — how far, how fast, on what power, in what environment — and get the wired and wireless options ranked for it, with the trade-offs, the red flags, and the certification burden spelled out.

No sign-up Shareable link 10 options · 25 sources

All 10 options

Side by side, before you choose

The same table the tool ranks against: bandwidth, power, range, security, interoperability, cost class, and what certification it drags in. Ranges are engineering rule of thumb; the protocols and the certification rules are sourced below.

Ten communications options compared on data rate, power, range, security, interoperability, cost class, and certification burden
Option	Bandwidth	Power	Range	Security	Interoperability	Cost class	Certification burden
Wi-Fi	10 Mbit/s to multi-gigabit (802.11ax peaks at 9.6 Gbit/s)	High: mains or USB. Association and keep-alives are the biggest battery drain in a connected product	About 30 m indoors, 100 m line of sight (rule of thumb: walls and floors decide)	WPA2/WPA3, with 802.1X in enterprise. Getting credentials into a screenless device is the real work	Phones, laptops, and routers; reaches your cloud over the existing network	Low	Radio: FCC Part 15C with an FCC ID, ISED RSS-247, EU RED and CE. Wi-Fi Alliance certification if you use the name
Bluetooth LE	2 Mbit/s on paper, roughly 100 kbit/s with the GATT overhead in practice	Very low: around 10 mA while connected, microamps asleep. A coin cell runs a sensor for years	About 10 m practical, up to 100 m line of sight (rule of thumb)	LE Secure Connections (ECDH and AES-CCM) with pairing and bonding. The pairing flow is where devices get stolen	Phones and tablets natively. Anything else needs a hub that speaks both	Low	Radio: FCC Part 15C with an FCC ID, ISED RSS-247, EU RED and CE. Bluetooth SIG qualification is mandatory for the name
Thread / Matter	250 kbit/s raw (802.15.4), tens of kbit/s of real payload	Low for end devices: sleepy battery sensors are the normal case. Mesh routers need mains	10 to 30 m per hop; the mesh covers a home or a floor of a building	AES-128-CCM at the link layer, network keys, and Matter's device attestation and access control on top	Building and smart-home systems. Phones reach it through the Matter controllers in iOS, Android, and the big ecosystems	Low	Radio: FCC Part 15C with an FCC ID, ISED RSS-247, EU RED and CE. Thread Group certification, then CSA Matter certification for the product
Zigbee	250 kbit/s raw (802.15.4), tens of kbit/s of payload	Low for end devices; routers need mains	10 to 30 m per hop; the mesh reaches a whole floor	AES-128 at the link layer with network and application keys; Zigbee 3.0 tightened the provisioning story	Building and HVAC products, mostly. Phones do not speak it	Low	Radio: FCC Part 15C with an FCC ID, ISED RSS-247, EU RED and CE. CSA certification for Zigbee products
LoRa / LoRaWAN	0.3 to 50 kbit/s, set by the spreading factor	Very low: a coin cell runs years between messages	About 2 km in a city, 10 km or more with line of sight (rule of thumb: the spreading factor decides)	LoRaWAN 1.1 uses AES-128 session keys and end-to-end encryption. 1.0 splits network and application keys, which is weaker	Building and plant sensing. Phones do not speak it, and you need gateway coverage	Low	Radio: FCC Part 15.247 for 902 to 928 MHz with an FCC ID, ISED, EU RED and CE, plus the regional duty-cycle and band-plan rules
Cellular IoT (LTE-M / NB-IoT)	LTE-M up to about 1 Mbit/s in practice; NB-IoT around 60 kbit/s	Medium to high: transmit current is in amps, so the battery needs a buffer. Power-save modes buy years	Wherever the carrier reaches: kilometres to hundreds, with no local link budget	Carrier authentication plus your own TLS. SIM identity, eSIM provisioning, and SMS ports need care	Any site with coverage: buildings, vehicles, machines, remote sites. A phone does not speak to it directly	Medium	Licensed radio: FCC Parts 22, 24, and 27 certification, then carrier acceptance (PTCRB) and operator approval per carrier
CAN bus	10 kbit/s to 1 Mbit/s; CAN FD reaches 8 Mbit/s in the data phase	Powered from the vehicle bus, so there is no battery to design	About 40 m at 1 Mbit/s, 100 m at 500 kbit/s, 1 km at 50 kbit/s (rule of thumb)	None in the protocol: anything on the bus can inject frames, so security has to live in a gateway or an ISO/SAE 21434 design	Vehicle ECUs, OBD-II diagnostics, and OEM networks. Nothing else	Low	No radio certification. Road vehicles: E-mark and UNECE R10 for EMC, plus the OEM's automotive quality expectations
RS-485 / Modbus	9.6 kbit/s to 10 Mbit/s, usually 9.6, 19.2, or 115.2 kbit/s	Low to medium: the transceiver idles around 1 mA, and bus-powered devices exist	About 1.2 km at 100 kbit/s (rule of thumb: 10 m per 100 kbit/s)	None: an unauthenticated serial-to-Ethernet gateway is often the weakest link in the whole system	Building management, HVAC, meters, and factory PLCs. Modbus is the common language	Low	No radio certification. As a product in the US: FCC Part 15B emissions. EU: EMC Directive. Mains-powered parts also need safety approval
Ethernet (incl. single-pair)	100 Mbit/s to 10 Gbit/s; single-pair runs 10 Mbit/s to 2.5 Gbit/s	Mains or PoE: the switch can power the device, 15 W to 90 W a port	100 m per copper segment. Single-pair Ethernet (10BASE-T1S) carries the link over one pair	None in the protocol: the switch's VLANs, 802.1X, and the physical port are the security	Building networks, plant floors, and cameras. No phone path without an adapter	Medium	No radio certification. As a product: FCC Part 15B or EU EMC. PoE parts also need safety approval; anything with a radio also needs RED or FCC 15C
USB	480 Mbit/s for USB 2.0; 5 to 20 Gbit/s for USB 3.2 and USB4	Powered by the host: 5 V by default, and up to 240 W with USB Power Delivery	About 3 m for USB 2.0, 5 m for USB 3.2	None in the protocol: a plugged-in device can act as the host, so it comes down to signed firmware and secure boot	Phones, laptops, and test equipment. A configuration and debug link, not a field network	Low	No radio certification. USB-IF certification for the logo, USB Power Delivery compliance above 5 V, and safety approval for mains-powered parts

Swipe the table sideways on a phone. Cost class is relative module cost, never a price.

Wi-Fi

Wireless · Low cost

The wireless network that is already there: internet, phones, and laptops, no new infrastructure.

Topology: Star through an access point; dozens of clients per AP

Wrong when Wrong when the device runs on a battery, when there is no network to join, or when it lives in a metal cabinet. It is also wrong when a phone has to reach the device and the phone is not on your network.

Wi-Fi Pre-certified radio module Antenna design and matching Wi-Fi Alliance: Discover Wi-Fi IEEE 802.11 (wireless LAN)47 CFR Part 15 Subpart C (eCFR)Radio Equipment Directive 2014/53/EU (EUR-Lex)

Bluetooth LE

Wireless · Low cost

The phone's radio: short range, tiny power, and no infrastructure at all.

Topology: Point-to-point or a small star: one central, a handful of peripherals

Wrong when Wrong when more than a handful of devices share one central, when the phone app has to keep working in the background, or when the payload is bigger than a few packets. It is also wrong for a device that a building system has to control.

Bluetooth Low Energy Over-the-air Pre-certified radio module Bluetooth Core Specification Bluetooth SIG: qualification listing 47 CFR Part 15 Subpart C (eCFR)Radio Equipment Directive 2014/53/EU (EUR-Lex)

Thread / Matter

Wireless · Low cost

A low-power IP mesh for a whole home or building, with Matter on top for the app layer.

Topology: Mesh: IPv6 over 802.15.4, with one border router to the wider network

Wrong when Wrong when you need bandwidth, when the building has no Thread border router and no Matter controller, or when a phone has to reach the device directly. It is also wrong when your customer has no smartphone and no home hub.

Thread Matter MQTT Pre-certified radio module Thread Group CSA: Matter 47 CFR Part 15 Subpart C (eCFR)Radio Equipment Directive 2014/53/EU (EUR-Lex)

Zigbee

Wireless · Low cost

The older mesh standard that building, HVAC, and sensing products already speak.

Topology: Mesh, with a coordinator as the bridge into IP

Wrong when Wrong when you want a modern IP stack, when the customers are on Matter or Thread, or when a phone app has to drive the product. It is also wrong when you need to carry anything but readings and commands.

MQTT Pre-certified radio module Node-RED CSA: Zigbee 47 CFR Part 15 Subpart C (eCFR)Radio Equipment Directive 2014/53/EU (EUR-Lex)

LoRa / LoRaWAN

Wireless · Low cost

Kilometres on a coin cell, for small messages sent now and then.

Topology: Star: devices to gateways, gateways to a network server

Wrong when Wrong when the data is not tiny: no video, no large update images. It is also wrong indoors behind concrete, when you need a fast round trip, or where there is no gateway coverage.

LoRa and LoRaWAN Antenna design and matching Pre-certified radio module LoRa Alliance: about LoRaWAN The Things Network: LoRaWAN regional parameters 47 CFR Part 15 Subpart C (eCFR)Radio Equipment Directive 2014/53/EU (EUR-Lex)

Cellular IoT (LTE-M / NB-IoT)

Wireless · Medium cost

Coverage instead of range: the carrier's network is the link.

Topology: Star to the carrier, with a SIM or eSIM per device

Wrong when Wrong where the carrier does not reach, when a per-device data plan makes the unit cost run away, or when the radio's amp-scale transmit current breaks the battery budget. It is also wrong when the link has to work with no signal and no power.

LTE-M and NB-IoT Pre-certified radio module 3GPP: LTE-M GSMA: NB-IoT PTCRB: about 47 CFR Part 22 (eCFR)

CAN bus

Wired · Low cost

The vehicle bus: deterministic, cheap, and already inside every car and machine.

Topology: Linear bus, multi-master, 120 ohm termination at both ends, one bus per ECU domain

Wrong when Wrong when you need security, bandwidth, or a link that crosses a building. It is also wrong outside a vehicle: CAN has no authentication, and it stops being deterministic the moment something else joins the bus.

CAN bus Predictive maintenance CAN in Automation: CAN knowledge ISO 11898-1 (CAN)

RS-485 / Modbus

Wired · Low cost

The field bus: a daisy chain of devices on one pair of twisted wires.

Topology: Daisy-chain bus: 32 unit loads per segment with modern transceivers, 120 ohm termination at both ends

Wrong when Wrong when you need security, when you need more than a few tens of kilobits, or when the nodes are far apart in a star. It is also wrong where the customer wants a phone app with no gateway in the middle.

RS-485 Modbus PLC MQTT TIA: standards (TIA-485-A, RS-485)Modbus Organization: specifications 47 CFR Part 15 Subpart B (eCFR)EMC Directive 2014/30/EU (EUR-Lex)

Ethernet (incl. single-pair)

Wired · Medium cost

Cabled IP: the network the building already has, with power over the same cable.

Topology: Star to a switch, a campus of switches, fibre between buildings

Wrong when Wrong when you cannot run cable, when the device is battery-powered, or when the product moves. It is also wrong when a physical port in a public place is a security decision you would rather not make.

Power over Ethernet MQTT Node-RED IEEE 802.3 (Ethernet)IEEE 802.3cg (single-pair Ethernet, 10BASE-T1S)47 CFR Part 15 Subpart B (eCFR)EMC Directive 2014/30/EU (EUR-Lex)

USB

Wired · Low cost

Short, fast, and powered by the host: the cable you already own.

Topology: Point-to-point: one host, one device, hubs for more

Wrong when Wrong when the device has to run unattended, when it moves, or when it is more than a few metres away. It is also wrong as the product's only link: unplug it and the product stops working.

USB Power Delivery USB-IF USB-IF: specifications and documents

free review

Want an engineer to check the shortlist?

Send the ranking to yourself, and get a free 15-minute review of your product with an engineer: which option we'd pick, what the module choice saves, and what to ask your lab. No sales sequence.

How the ranking works

Eight dimensions, each with a weight: range, data rate, power, phone, existing system, environment, security, and cost. Every option is scored 0 to 1 on each one against your inputs.
Range and data rate are pass or fail with a margin: an option that reaches 2 km when you need 100 m scores full marks, and one that reaches 20 m scores almost nothing. The shortfall is proportional, not a cliff.
Power only bites when you are on a battery: a coin-cell radio keeps full marks for a five-year target, a mains-powered radio loses most of them.
Existing system decides the wired-versus-wireless fight: an option that joins the system you named wins, and one that needs a hub or gateway you would have to build loses.
Environment is per option, not per rule: LoRa is superb outdoors and poor indoors, CAN is superb in a vehicle and poor anywhere else.
Red flags come from the option's own entry: a dimension that falls below its threshold says the specific thing that will go wrong, not a generic warning.
Scale is a flat penalty when you have more devices on one link than that link comfortably carries.
Ties break in the order the options are listed in the data file, so the result is stable.

All of it lives in one open data file, comms-rules.json. Model v1.0, updated 2026-10-22.

How srvo helps

The radio choice is an engineering decision, not a preference.

Most connectivity mistakes are made in the first week, when the radio is picked from a datasheet and the antenna, the enclosure, the power budget, and the certification plan follow later. We make those choices together: module and antenna in the same review as the battery, the enclosure, and the lab dates.

The usual first step is a connectivity review: a fixed-fee look at your product and the options above, ending with the link we would pick, the trade-offs we would accept, and the certification lane it puts on your schedule.

Start a project ↵

Certification mapWhich approvals your radio or product needs, market by market. Battery life calculatorWhat the radio costs you in the power budget. Production readiness sprintA funded-ready roadmap with the risks already worked.

FAQ

Questions founders ask

Should I pick Wi-Fi or Bluetooth LE?

Pick Wi-Fi when the device is mains-powered and needs internet: phones, laptops, and your cloud are already on that network. Pick Bluetooth LE when the phone is the other end and the battery has to last years. The two are not rivals: many products ship BLE for setup and commissioning and Wi-Fi for the data.

How do I know if my range is realistic?

Take the worst case, not the happy path: the far end of the building, a metal cabinet, a concrete wall. The numbers in the table are engineering rule of thumb, because range is not a specification: it depends on the antenna, the enclosure, the body of the person standing there, and the noise around it. If a link has to work at 2 km, LoRa or cellular is the realistic answer.

What does the certification burden cost me in time?

Any radio (Wi-Fi, BLE, Thread, Zigbee, LoRa, cellular) needs certification: FCC Part 15C with an FCC ID in the US, ISED in Canada, and the Radio Equipment Directive in Europe. On top of that, Thread and Matter add ecosystem certification, and cellular adds carrier acceptance (PTCRB) per operator. A pre-certified module carries most of that load; the finished product still needs its own EMC and safety work. The certification map spells that out market by market.

Why is the wired option not ranked first?

Because the ranking follows your inputs, not a fashion. Ethernet and USB carry far more data than any radio, but they need cable, a port, or a host: if your device has to be wireless, unattended, or on a battery, those points go to the radios. Ask for the range and power you really need, and the ranking follows.

Who made this, and has an engineer reviewed it?

srvo built it from the protocol specifications and the standards bodies listed below, with the ranges as engineering rule of thumb. Engineer review of the rules is still pending, so treat it as a shortlist to argue with, not a sign-off. If you want an engineer to look at your product specifically, send the result and we will tell you what we would check.

Sources & assumptions

Defaults are starting points drawn from these sources, not quotes for your product. Every number above is editable; replace them with your own quotes as soon as you have them.

Wi-Fi Alliance: Discover Wi-Fi — What the Wi-Fi name covers, and the generations of 802.11 in use.
IEEE 802.11 (wireless LAN) — The standard fixes the rates and the PHY. It does not fix a range: every range number here is rule of thumb.
Bluetooth Core Specification — LE rates, power classes, and the security model.
Bluetooth SIG: qualification listing — Qualification (and the cost of it) is required before you may use the Bluetooth name or logo.
Thread Group — The Thread protocol, the certification programme, and the mesh rules.
CSA: Matter — Matter's application layer, device attestation, and the certification path.
CSA: Zigbee — Zigbee 3.0, the certification programme, and the current specification downloads.
LoRa Alliance: about LoRaWAN — The LoRaWAN network protocol, its security model, and the regional parameters.
The Things Network: LoRaWAN regional parameters — Band plans, duty-cycle limits, and dwell time per region: the same module is not the same radio everywhere.
3GPP: LTE-M — LTE-M as standardised: data rates, power-save modes, and coverage behaviour.
GSMA: NB-IoT — NB-IoT coverage, power, and deployment guidance from the mobile industry.
PTCRB: about — Carrier acceptance for cellular devices: the step after the radio certification.
CAN in Automation: CAN knowledge — CAN, CAN FD, and the bus rules the CiA publishes.
ISO 11898-1 (CAN) — The CAN protocol standard. Bitrate-to-distance figures here are rule of thumb, not standard values.
TIA: standards (TIA-485-A, RS-485) — The RS-485 standard and its revisions; the unit-load and distance limits come from here.
Modbus Organization: specifications — The Modbus application protocol and the serial-line rules.
IEEE 802.3 (Ethernet) — Copper segment lengths and PoE classes.
IEEE 802.3cg (single-pair Ethernet, 10BASE-T1S) — Single-pair Ethernet: one pair, one device, industrial and automotive reach.
USB-IF — The USB specification, the compliance programme, and the trademark rules.
USB-IF: specifications and documents — Cable lengths, data rates, and the Power Delivery rules.
47 CFR Part 15 Subpart C (eCFR) — Licence-exempt radiators need certification and an FCC ID before you market them in the US.
47 CFR Part 15 Subpart B (eCFR) — Wired products with digital electronics still have emissions limits.
47 CFR Part 22 (eCFR) — Cellular transmitters are licensed radios, not licence-exempt ones.
Radio Equipment Directive 2014/53/EU (EUR-Lex) — The EU's radio rules: safety, EMC, and spectrum in one assessment.
EMC Directive 2014/30/EU (EUR-Lex) — The EU's EMC rules for products without a radio.