897  Bluetooth Technology Overview

Comprehensive Guide to Bluetooth and BLE for IoT

networking
wireless
bluetooth
ble
iot
Author

IoT Textbook

Published

January 19, 2026

Keywords

bluetooth, ble, bluetooth low energy, wireless, iot, piconet, gatt, mesh

897.1 Overview

Bluetooth has evolved from a simple cable replacement technology to one of the most ubiquitous wireless standards for IoT. Present in billions of devices worldwide, Bluetooth enables short-range communication between smartphones, sensors, wearables, and smart home devices.

This chapter series provides comprehensive coverage of Bluetooth technology for IoT applications, from fundamental concepts to advanced mesh networking and security.

897.2 Chapter Series

897.2.1 1. Bluetooth Fundamentals and Evolution

Core concepts and technology comparison:

  • Bluetooth Classic vs BLE differences
  • Frequency Hopping Spread Spectrum (FHSS)
  • Adaptive Frequency Hopping (AFH)
  • Version evolution from 1.0 to 5.4
  • Technology selection decision tree

897.2.2 2. Bluetooth Network Architecture

Network topologies and power management:

  • Piconet structure and 7-device limitation
  • Master-slave communication model
  • Power classes (Class 1, 2, 3) and range
  • Scatternet topology for larger networks
  • BLE connection states and parameters

897.2.3 3. BLE Protocol Stack and GATT

Protocol architecture and data exchange:

  • BLE protocol stack layers (PHY to Application)
  • Generic Attribute Profile (GATT) client-server model
  • Services, Characteristics, and Descriptors
  • Standard Bluetooth profiles (HID, Heart Rate, etc.)
  • iBeacon and Eddystone beacon formats

897.2.4 4. Bluetooth Implementation and Labs

Hands-on development with ESP32:

  • BLE Scanner implementation
  • GATT Server (Temperature Sensor)
  • iBeacon transmitter
  • Indoor positioning with trilateration
  • Common development mistakes

897.2.5 5. Bluetooth Mesh and Advanced Topics

Large-scale networks and security:

  • BLE Mesh architecture and node types
  • TTL management and capacity planning
  • Pairing methods and security levels
  • LE Secure Connections (BLE 4.2+)
  • Troubleshooting guide

897.2.6 6. Bluetooth Assessment and Exercises

Comprehensive knowledge validation:

  • Quick review quizzes
  • Scenario-based questions
  • Technical deep-dive problems
  • Calculation exercises
  • Practice implementation exercises

897.3 Key Concepts Summary

Concept Description
Classic Bluetooth Connection-oriented for audio/data streaming
BLE Ultra-low power for sensors and IoT
Piconet 1 master + up to 7 active slaves
GATT Service/characteristic model for data exchange
Pairing/Bonding Security authentication and key storage
BLE Mesh Many-to-many communication (32K+ nodes)

897.4 Quick Reference

When to use Classic Bluetooth: - Continuous audio streaming (headphones, speakers) - High-throughput file transfer - Legacy device compatibility

When to use BLE: - Battery-powered sensors - Beacon/proximity applications - Smartphone-connected IoT devices - Low-latency periodic data

When to use BLE Mesh: - Building automation (lighting, HVAC) - Large-scale sensor networks - Self-healing network requirements

897.6 What’s Next

Start with Bluetooth Fundamentals and Evolution to learn the core concepts, or jump directly to the chapter most relevant to your needs.