IoT Protocols & Networking Guides
IoT networking is a different world from regular internet networking. Battery-powered sensors that wake up once an hour, mesh networks that route messages hop-by-hop, industrial PLCs running protocols designed in the 1970s — all need to interoperate with cloud platforms and consumer apps. The protocols that solve these problems are weird and specialized. This section explains the major ones in plain English: how MQTT, CoAP, Zigbee, Thread, Z-Wave, Matter, Modbus, and OPC UA actually work, and the architecture patterns that combine them into working systems.
Where to start
For most cloud-connected IoT projects, start with what is MQTT — the dominant publish/subscribe protocol for device-to-cloud communication. If you are building constrained devices that need RESTful semantics over UDP, see CoAP vs MQTT vs HTTP.
For consumer smart home devices, see Zigbee vs Thread vs Z-Wave for the radio layer, then Matter for the unified application layer landing on top.
For industrial / OT systems, see industrial IoT protocols for Modbus, OPC UA, and the legacy-to-modern bridges that connect factory floors to clouds.
Application protocols
The protocols devices use to talk to cloud platforms and apps.
Application Protocols
What is MQTT?
The dominant pub/sub protocol for IoT — brokers, topics, QoS, keep-alive.
CoAP vs MQTT vs HTTP
When to pick each transport for IoT — pub/sub vs request/response, UDP vs TCP.
MQTT QoS Levels Explained
QoS 0, 1, 2 in detail — at-most-once, at-least-once, exactly-once delivery.
MQTT Topics and Wildcards
Topic design, + and # wildcards, and ACL implications.
MQTT Retained Messages
Last-known-state for late-joining subscribers, plus the LWT pattern.
CoAP Protocol Deep Dive
Constrained Application Protocol — Observe, block-wise transfer, DTLS.
Wireless Networks
Zigbee vs Thread vs Z-Wave
Three smart home mesh standards compared — radio, range, ecosystem.
Matter Protocol Explained
The unified smart home standard from Apple, Google, Amazon — what it is and what it solves.
What Is LoRaWAN
Long-range low-power wide-area networking for IoT.
Bluetooth Low Energy for IoT
BLE GATT, advertising, BLE 5, and BLE Mesh.
Architecture & Industrial
IoT Device Network Architecture
Gateways, edge processing, cloud, and the patterns that scale.
Industrial IoT Protocols
Modbus, OPC UA, and the OT/IT bridges that connect factories to clouds.
Edge vs Cloud IoT
Where IoT workloads should actually run — device, gateway, or cloud.
IoT Addressing and IPv6
6LoWPAN, Thread, and IP at the edge.