CONNECTED TECHNOLOGY. CLEARLY EXPLAINED.
Topics & protocols
Make sense of connected-technology terms. Find plain definitions, illustrative examples and practical checks, with links to primary references and deeper protocol guides.
A practical IoT glossary
Start with the featured protocol definitions below, or search a term or abbreviation. Each definition includes an example and a question to check when applying the idea. Use “Show more entries” to continue through the directory.
Definitions give you a starting point. Follow the primary references and full protocol guides for implementation details, supported versions and the requirements of a particular device or service.
PROTOCOL DEFINITION
Bluetooth LE
Bluetooth communication designed for connected and broadcast exchanges between supported devices with constrained energy use.
Illustrative example: A tracker exchanges records with its supported phone application.
Check: Check supported roles, services, phone or gateway dependencies and practical connection behaviour for the intended function.
Search terms: BLE; Bluetooth Low Energy
Bluetooth LE primary reference. Short definition; the full protocol guide documents additional sources and limits.
PROTOCOL DEFINITION
LoRaWAN
A networking specification for low-power wide-area devices using LoRa radio technology and defined network-service roles.
Illustrative example: A field sensor's payload passes through a gateway and network service to its application.
Check: Plan devices, gateways and network service roles around payloads, coverage, power and the relevant regional requirements.
Search terms: LoRa wide-area network; LPWAN
LoRaWAN primary reference. Short definition; the full protocol guide documents additional sources and limits.
PROTOCOL DEFINITION
LTE-M
A cellular IoT technology offering supported device and network capabilities for particular communication workloads.
Illustrative example: A moving tracker needs the actual module, operator support and service plan assessed together.
Check: Confirm module, operator and local network support, coverage, provisioning and power behaviour for the intended deployment.
Search terms: LTE Cat-M1; cellular IoT
LTE-M primary reference. Short definition; the full protocol guide documents additional sources and limits.
PROTOCOL DEFINITION
Matter
An IP-based connected-device application standard defining supported device types and interactions across implemented systems.
Illustrative example: A controller and accessory need support for the particular requested feature.
Check: Check the exact device type, controller and implemented features. Matter uses supported networks and does not replace every vendor app or service.
Search terms: Matter application protocol; connected-home interoperability
Matter primary reference. Short definition; the full protocol guide documents additional sources and limits.
PROTOCOL DEFINITION
Modbus
An application protocol for exchanging structured data through supported serial or network transport arrangements.
Illustrative example: A register value needs the correct address map, unit and access permissions.
Check: Verify transport, device roles, register maps, units and access controls for the exact implementation.
Search terms: Modbus RTU; Modbus TCP
Modbus primary reference. Short definition; the full protocol guide documents additional sources and limits.
PROTOCOL DEFINITION
MQTT
An application messaging protocol in which clients exchange topic-based messages through a server or broker.
Illustrative example: A sensor publishes a reading that an authorized application subscribes to.
Check: Review broker access, topic permissions, session settings and message delivery handling for the intended device workflow.
Search terms: publish subscribe messaging; MQTT broker
MQTT primary reference. Short definition; the full protocol guide documents additional sources and limits.
PROTOCOL DEFINITION
NB-IoT
A cellular IoT technology intended for constrained connected-device workloads using supported network and module features.
Illustrative example: An installed meter needs coverage and report timing checked at its actual location.
Check: Check actual operator coverage, device support, upload pattern and downlink requirements rather than relying on a broad coverage claim.
Search terms: narrowband IoT; LTE Cat-NB
NB-IoT primary reference. Short definition; the full protocol guide documents additional sources and limits.
PROTOCOL DEFINITION
OPC UA
An industrial interoperability architecture with services, information models and security mechanisms implemented by supported applications.
Illustrative example: A client interprets an asset variable using the server's supported information model.
Check: Evaluate supported roles, information models, identities and permissions for an industrial exchange rather than relying on the protocol badge.
Search terms: OPC Unified Architecture
OPC UA primary reference. Short definition; the full protocol guide documents additional sources and limits.
PROTOCOL DEFINITION
Thread
An IPv6-based low-power mesh network technology used beneath supported connected-device applications.
Illustrative example: A border router connects a Thread network to an adjacent IP network.
Check: Check device and border-router roles, network credentials and recovery. Distinguish the network from an application protocol such as Matter.
Search terms: Thread network; border router
Thread primary reference. Short definition; the full protocol guide documents additional sources and limits.
PROTOCOL DEFINITION
Wi-Fi
A family of wireless local-network technologies through which devices communicate with supported access points or peers.
Illustrative example: A camera joins the documented local network before its app reaches a remote service.
Check: Check the exact band and security support, coverage and network requirements of each device at its intended installation point.
Search terms: wireless LAN; WLAN
Wi-Fi primary reference. Short definition; the full protocol guide documents additional sources and limits.
PROTOCOL DEFINITION
Z-Wave
A connected-device wireless technology with supported application roles and region-specific radio implementations.
Illustrative example: An imported accessory needs the correct regional radio and controller support.
Check: Check the regional device variant, controller support and intended functions before choosing or importing hardware.
Search terms: ZWave; Z-Wave regional variant
Z-Wave primary reference. Short definition; the full protocol guide documents additional sources and limits.
PROTOCOL DEFINITION
Zigbee
A connected-device technology with networking and application definitions built on IEEE 802.15.4 radio foundations.
Illustrative example: A supported hub exposes a particular accessory's implemented controls.
Check: Verify the device, coordinator and supported application functions. A radio label alone does not establish every integration feature.
Search terms: IEEE 802.15.4 ecosystem; Zigbee coordinator
Zigbee primary reference. Short definition; the full protocol guide documents additional sources and limits.
PROTOCOL DEFINITION
4G
A mobile-network generation commonly associated with LTE-family services; its label does not specify a complete device or service capability.
Illustrative example: A router needs supported bands and an appropriate operator plan.
Check: Evaluate the selected modem, bands, operator plan and service coverage along the actual deployment area or route.
Search terms: LTE; LTE-Advanced; fourth-generation mobile
3GPP: Mobile Broadband Technologies. Generation context; no operator coverage or service guarantee.
PROTOCOL DEFINITION
5G
A mobile-system generation supporting varied network capabilities whose availability depends on the implemented device and network arrangement.
Illustrative example: A 5G modem label does not establish an application's end-to-end latency.
Check: Check modem capabilities, network availability, plan terms and application needs; the generation label alone does not guarantee latency.
Search terms: NR; fifth-generation mobile
3GPP: Mobile Broadband Technologies. Generation context; no operator coverage or service guarantee.
TOPIC DEFINITION
Acoustic intelligence
Methods that infer defined events or patterns from sound recordings or acoustic measurements.
Illustrative example: A model flags a particular sound class for a human to investigate.
Check: Record microphones, background noise and the sound classes being evaluated; distinguish useful detection from a complete diagnosis.
Search terms: sound event detection; audio classification
TensorFlow: Model Optimization. Model-efficiency context; validate the selected task separately.
TOPIC DEFINITION
Agent permissions
The allowed data access and actions of software acting toward a goal using models and tools.
Illustrative example: An assistant may read an equipment record without permission to issue a control command.
Check: Grant only the tools and data needed for a defined task, with explicit boundaries on consequential actions and an audit trail.
Search terms: tool authorization; least privilege agents
OWASP: Excessive Agency. Agent-authorization context; no security certification.
TOPIC DEFINITION
Anomaly detection
Methods that identify observations or patterns differing from an expected reference behaviour.
Illustrative example: An unusual vibration window is flagged for investigation rather than declared a failure.
Check: Define a relevant normal baseline and record false alerts, missed events and investigation effort alongside detections.
Search terms: outlier detection; novelty detection
scikit-learn: Model Evaluation. Evaluation-method context; no deployment-quality claim.
TOPIC DEFINITION
Assistant integrations
Connections that expose selected device information or actions through an assistant's supported interfaces.
Illustrative example: A voice command may control a lamp while detailed settings remain in its app.
Check: Check which commands and device states an assistant integration supports, along with accounts, permissions and service dependencies.
Search terms: voice assistant integration; device commands
W3C: WoT Architecture 1.1. Architecture context; exact implementations require separate documentation.
TOPIC DEFINITION
Attestation
Evidence about a device or software state that a verifier evaluates under a defined trust policy.
Illustrative example: A verifier checks a signed statement about an identified platform's measured state.
Check: Check what device or software state is evidenced, who verifies it and the limitations of the trust decision.
Search terms: remote attestation; platform evidence
NIST: Platform Firmware Resiliency. Firmware protection, detection and recovery context; no device audit.
TOPIC DEFINITION
Backup recovery
Restoration of required data or configuration from a protected backup through a supported recovery process.
Illustrative example: A controller backup is useful only with the material and procedure needed to restore it.
Check: Record what the backup contains and where recovery materials are kept. Verify a supported restoration process before depending on the installation.
Search terms: restore testing; configuration backup
NIST: Contingency Planning Guide. Planning context; adapt to the actual system and responsibilities.
PROTOCOL DEFINITION
Bluetooth Mesh
Additional Bluetooth networking models and procedures for many-to-many device communication, with explicit provisioning and application support.
Illustrative example: A building-lighting group uses implemented mesh models rather than ordinary phone pairing alone.
Check: Review provisioning, supported models and network design for the intended mesh application; verify exact device interoperability.
Search terms: Bluetooth mesh networking
Bluetooth SIG: Mesh Networking. Technology context; exact mesh models and product support vary.
TOPIC DEFINITION
Building access integrations
Connections that coordinate access identities, permissions and events with a building's approved operating system.
Illustrative example: Ending a visitor booking should follow the supported credential-revocation process.
Check: Define enrollment, guest access, revocation and documented emergency or manual operation with the responsible building operator.
Search terms: access control integration; guest credentials
NIST: OT Security, Revision 3. Operational-system context; not an integration approval.
PROTOCOL DEFINITION
CAN bus
A communication bus technology used for exchanging defined messages among supported controllers and devices.
Illustrative example: A readable frame still needs the correct message definition for interpretation.
Check: Check the specific network, message definitions and approved integration method; a physical connection does not authorize control commands.
Search terms: Controller Area Network; CAN
Bosch: CAN Controller IP. CAN-family context; variant and message definitions must match.
TOPIC DEFINITION
Carbon reporting integrations
Connections that supply activity or measurement records to an emissions-accounting process with an explicit boundary.
Illustrative example: An electricity record needs the applicable calculation method before becoming an emissions estimate.
Check: Keep measurement boundaries, source data, assumptions and calculation methods explicit. Transferring readings does not validate an emissions claim.
Search terms: emissions data integration; GHG inventory
GHG Protocol: Corporate Standard. Accounting-boundary context; no emissions inventory verified.