657  IoT Protocols Overview

NoteLearning Objectives

By the end of this section, you will be able to:

  • Understand why traditional internet protocols need adaptation for IoT
  • Identify protocols at each layer of the IoT protocol stack
  • Compare IPv4 and IPv6 for IoT applications
  • Understand the role of 6LoWPAN in IoT networks
  • Compare CoAP and MQTT application protocols
  • Map protocols to the TCP/IP layer model
  • Select appropriate protocols for different IoT scenarios

657.1 Prerequisites

Before diving into this chapter, you should be familiar with:

  • Networking Basics for IoT: Understanding of fundamental networking concepts, TCP/IP stack, and protocol layers provides the foundation for learning about specialized IoT protocols
  • Layered Models: Fundamentals: Knowledge of the OSI and TCP/IP layered models is essential for understanding where each IoT protocol fits in the stack (application, transport, network, link layers)
  • IoT Protocols: Fundamentals: Basic understanding of why IoT requires specialized protocols helps contextualize the specific protocols covered in this overview chapter

657.2 Chapter Overview

IoT protocols form the communication backbone that enables billions of connected devices to exchange data reliably and efficiently. Unlike traditional internet protocols designed for desktop computers and servers, IoT protocols must operate within severe constraints: limited memory (kilobytes, not gigabytes), low processing power (MHz, not GHz), battery operation (years, not hours), and unreliable wireless links (10-40% packet loss).

This comprehensive guide is organized into six focused chapters, each addressing a critical aspect of IoT protocol design and selection:

657.2.1 Chapter Guide

Chapter Topic Key Content Estimated Time
1 Introduction to IoT Protocols Why IoT needs specialized protocols, protocol stack layers, deployment scenarios 15 min
2 IPv6 and 6LoWPAN IPv6 addressing for IoT, 6LoWPAN header compression, Thread integration 20 min
3 Application Layer Protocols CoAP vs MQTT comparison, interactive comparison tools, protocol selection 25 min
4 Protocol Selection Guide Decision frameworks, comparison matrices, interactive selector tool 20 min
5 Protocol Overhead Analysis Battery life calculations, overhead comparison, hands-on labs 25 min
6 Real-World Protocol Examples Tilt maze case study, use case analysis, deployment patterns 20 min

657.2.2 Quick Reference: Protocol Stack

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graph TB
    subgraph "Application Layer"
        CoAP["CoAP<br/>RESTful UDP"]
        MQTT["MQTT<br/>Pub/Sub TCP"]
        HTTP["HTTP<br/>Web APIs"]
    end

    subgraph "Transport Layer"
        UDP["UDP<br/>Connectionless"]
        TCP["TCP<br/>Reliable"]
    end

    subgraph "Network Layer"
        IPv6["IPv6<br/>128-bit addresses"]
        RPL["RPL<br/>Routing"]
    end

    subgraph "Adaptation Layer"
        LoWPAN["6LoWPAN<br/>Header compression"]
    end

    subgraph "Link Layer"
        IEEE["802.15.4<br/>Zigbee/Thread"]
        BLE["Bluetooth LE"]
        LoRa["LoRaWAN"]
    end

    CoAP & MQTT --> UDP & TCP
    UDP & TCP --> IPv6
    IPv6 --> RPL
    RPL --> LoWPAN
    LoWPAN --> IEEE & BLE
    HTTP --> TCP

    style CoAP fill:#2C3E50,stroke:#16A085,stroke-width:2px,color:#fff
    style MQTT fill:#2C3E50,stroke:#16A085,stroke-width:2px,color:#fff
    style LoWPAN fill:#16A085,stroke:#2C3E50,stroke-width:2px,color:#fff
    style IPv6 fill:#E67E22,stroke:#2C3E50,stroke-width:2px

657.2.3 Key Concepts at a Glance

Concept What It Does Why It Matters
6LoWPAN Compresses IPv6 headers from 40 to 6 bytes Enables IPv6 on constrained 802.15.4 networks
CoAP RESTful protocol over UDP with 4-byte header 10x more efficient than HTTP for IoT
MQTT Publish-subscribe messaging over TCP Scales to millions of devices via broker
IPv6 340 undecillion addresses Every IoT device gets unique global address
RPL Routing for lossy networks Builds mesh routes for battery-powered sensors

657.2.4 Learning Path Recommendations

For Beginners: Start with Introduction to IoT Protocols to understand why specialized protocols matter, then proceed to Application Layer Protocols for practical CoAP vs MQTT comparison.

For Practitioners: Jump to Protocol Selection Guide for decision frameworks, then reference Protocol Overhead Analysis for battery life calculations.

For Deep Understanding: Work through all chapters sequentially, completing the hands-on labs in Protocol Overhead Analysis and studying the Real-World Protocol Examples.

657.3 Videos

NoteProtocol Stack Overview
Protocol Stack Overview
Lesson 4 β€” foundational networking concepts used across IoT protocols.
NoteApplication Protocols in Context
Application Protocols in Context
Lesson 4 β€” MQTT vs CoAP vs HTTP vs AMQP and when to use each.

657.4 What’s Next?

Start your journey through IoT protocols with Introduction to IoT Protocols to understand why traditional internet protocols need adaptation for resource-constrained devices.

Deep Dives: - MQTT Fundamentals - Publish-subscribe messaging protocol - CoAP Architecture - Constrained Application Protocol - HTTP for IoT - RESTful API design - AMQP vs MQTT - Enterprise messaging comparison

Comparisons: - IoT Protocols Review - Comprehensive protocol comparison - Protocol Selection Framework - Decision tree for protocol choice - Transport Protocols - TCP vs UDP for IoT

Architecture: - Layered Network Models - Protocol stack organization - IoT Reference Models - Where protocols fit in IoT architecture