HCIA-IoT key terms

A network of physical objects embedded with sensors, software, and network connectivity that collect and exchange data with other devices and systems over the internet, enabling remote monitoring and automated control.

The lowest layer of the classic IoT architecture model, containing sensors, actuators, and smart devices that gather physical-world data and execute commands. It converts analog environmental conditions into digital signals for upper layers.

The IoT architecture layer that transports data from perception devices to platforms and applications. It covers access networks, bearer networks, and protocols such as cellular, Wi-Fi, Ethernet, and LPWA technologies.

The top IoT architecture layer where collected data is processed, stored, and presented to users through industry applications such as smart metering, fleet tracking, or building management systems.

A device that detects a physical quantity such as temperature, humidity, light, motion, or pressure and converts it into an electrical signal that can be digitized, transmitted, and analyzed.

A component that converts an electrical control signal into physical action, such as opening a valve, moving a motor, or switching a relay. Actuators let IoT systems change the environment, not just observe it.

An intermediate device that aggregates data from local sensors, performs protocol conversion or edge preprocessing, and forwards traffic to a wider network. It bridges short-range device networks with cellular or IP backhaul.

Processing data near the source, on gateways or devices, instead of sending everything to a central cloud. It reduces latency and bandwidth use and allows local decisions when connectivity is intermittent.

On-demand delivery of computing, storage, and networking resources over the internet with elastic scaling. IoT platforms commonly run device management, data storage, and analytics in cloud environments.

Low Power Wide Area: a family of wireless technologies designed for long-range, low-bitrate, battery-powered devices. Examples include NB-IoT and LoRa, suited to meters, sensors, and tracking tags.

Narrowband IoT: a licensed-spectrum cellular LPWA standard using a 180 kHz bandwidth. It offers deep indoor coverage, low power consumption, massive connection density, and support for power-saving features.

A chirp spread spectrum physical-layer modulation for long-range, low-power links in unlicensed ISM bands. It is often paired with the LoRaWAN protocol for network management and security.

An open MAC-layer protocol built on LoRa radios, defining device classes, join procedures, and network topology with gateways forwarding frames to a network server. It supports bidirectional and multicast traffic.

A low-power, short-range mesh networking standard based on IEEE 802.15.4, widely used in home and building automation. Devices relay traffic for each other to extend coverage without extra infrastructure.

A short-range wireless technology optimized for very low power consumption, common in wearables, beacons, and local device configuration. It supports point-to-point links and star topologies rather than wide-area coverage.

A lightweight publish-subscribe messaging protocol over TCP, using a broker to route topics between clients. Its small headers and quality-of-service levels suit constrained devices and unreliable networks.

Constrained Application Protocol: a REST-style request-response protocol over UDP for very limited devices. It uses compact binary headers and supports observe mode for server-pushed state changes.

Quality of Service: in MQTT, the delivery guarantee level for a message, ranging from at most once to exactly once. More broadly, it describes how a network prioritizes or guarantees traffic characteristics.

Lightweight Machine to Machine: a device management protocol from the Open Mobile Alliance built on CoAP. It defines object models for registration, firmware updates, and remote configuration of constrained devices.

Power Saving Mode: a cellular feature where a device deregisters from the network and sleeps for a configured period while keeping its session context, waking to send data without reattaching.

Extended Discontinuous Reception: a power-saving mechanism that lengthens the interval between paging opportunities so a device can sleep longer while remaining reachable for downlink data.

A topology in which nodes connect to multiple peers and relay traffic for one another, so coverage grows with node density. It offers path redundancy but adds complexity and hop latency.

The internet protocol version with 128-bit addresses, providing a vast address space that lets huge numbers of IoT devices be individually addressed without translation.

IPv6 over Low-Power Wireless Personal Area Networks: an adaptation layer that compresses IPv6 headers and fragments packets so IPv6 can run over IEEE 802.15.4 links.

An IP-based, low-power mesh networking protocol built on IEEE 802.15.4 with 6LoWPAN adaptation, designed for secure home automation and native IPv6 connectivity to each node.

A software layer that connects devices, manages their lifecycle, ingests and stores telemetry, exposes APIs, and provides rules or analytics so applications can be built without handling raw connectivity.

The set of functions for registering, provisioning, configuring, monitoring, updating, and retiring connected devices at scale, including credential handling and remote diagnostics.

A software model that mirrors a physical asset's state and behavior using live telemetry. It supports simulation, predictive maintenance, and what-if analysis without touching the real device.

Automatically collected measurement data sent from remote devices to a monitoring system. In IoT it usually means periodic or event-driven sensor readings carried over a messaging protocol.

Measurements indexed by timestamp, such as hourly meter readings or per-second temperature values. Its volume and ordering requirements shape how IoT platforms store and query telemetry.

Delivering firmware or software updates to devices remotely over a network. A safe design uses staged rollout, integrity checks, and rollback so a failed update does not brick a fleet.

The downlink path that sends instructions from an application or platform to a device, such as opening a valve or changing a setpoint. It requires authentication and often acknowledgement.

Verifying that a device or user is genuine before granting access, typically through certificates, pre-shared keys, or tokens. Weak device identity is a common cause of IoT breaches.

A TLS handshake in which both client and server present certificates and validate each other. In IoT it gives strong device-to-platform authentication and encrypted transport in one step.

Rules that decide which users, services, or devices may perform which actions on which resources. Least-privilege policies limit the damage a compromised device or credential can cause.

A startup process that verifies the cryptographic signature of firmware before execution, blocking tampered or unauthorized code. It anchors device trust and complements encrypted update delivery.

A network of compromised devices controlled remotely by an attacker. IoT botnets such as Mirai recruit weakly secured devices and launch large distributed denial-of-service attacks.

An IoT application where utility meters report consumption remotely and support remote disconnect or tariff changes. It relies on LPWA or cellular links and strict security for billing integrity.

Using sensor data and models to forecast equipment failure before it happens, so maintenance is scheduled just in time. It is a leading industrial IoT use case that cuts downtime and spare-part costs.