Understanding Eddystone: The Open-Source Beacon Solution

Eddystone is an open-source, cross-platform Bluetooth Low Energy (BLE) beacon format developed by Google in 2015. It is designed to enable proximity-based communication between BLE beacons and compatible devices (smartphones, tablets, IoT sensors), allowing beacons to broadcast standardized data packets for use cases like location-based services, asset tracking, and contextual notifications. Unlike proprietary beacon formats (e.g., Apple’s iBeacon), Eddystone is vendor-agnostic, supporting both Android and iOS devices, and offers flexible packet types to accommodate diverse application needs.

Core Technical Features

1. Key Characteristics of Eddystone Beacons

BLE Low Energy Operation: Uses Bluetooth 4.0+ Low Energy technology, ensuring low power consumption (battery life of months to years for small beacons) and compatibility with most modern mobile devices.
Open Standard: No licensing fees or proprietary restrictions; the specification is publicly available for developers and hardware manufacturers.
Multi-Packet Support: Transmits different packet types to serve distinct use cases, with beacons able to broadcast multiple packet formats simultaneously.
Cross-Platform Compatibility: Works with Android (via Google Play Services) and iOS (via Core Bluetooth framework), eliminating platform lock-in.

2. Eddystone Packet Types

Eddystone defines four primary packet formats, each optimized for specific proximity-based applications:

Packet Type	Full Name	Core Function	Key Technical Details	Typical Use Case
UID	Unique ID Packet	Broadcasts a unique, static identifier for beacon tracking	– Consists of a 10-byte Namespace ID (for organizational grouping) and a 6-byte Instance ID (for individual beacon identification).- Does not include location or URL data.	Asset tracking (e.g., monitoring equipment in a warehouse), indoor positioning system (IPS) mapping.
URL	URL Packet	Broadcasts a compressed web link that devices can resolve and open	– Uses a compact URL encoding scheme to fit web addresses into BLE’s limited payload (max 17 bytes after compression).- Supports prefixes like `http://www.`, `https://`, `ftp://` to reduce byte usage.	Proximity marketing (e.g., a beacon in a café broadcasts a menu URL; users receive a link when nearby), museum exhibit information.
TLM	Telemetry Packet	Transmits beacon health and status data (non-user-facing)	– Includes metrics like battery voltage, beacon temperature, uptime, and broadcast count.- Sent periodically alongside UID/URL packets to enable remote monitoring.	Beacon fleet management (e.g., alerting administrators when a beacon’s battery is low), troubleshooting signal strength issues.
EID	Ephemeral ID Packet	Broadcasts a rotating, encrypted identifier for secure proximity tracking	– Uses public-key cryptography to generate time-limited, unique IDs that change at predefined intervals (e.g., every few minutes).- Prevents unauthorized tracking or spoofing of beacons.	Secure asset tracking (e.g., high-value goods in a supply chain), privacy-focused location services.

How Eddystone Works

The Eddystone ecosystem operates in a simple, three-step workflow between beacons, mobile devices, and backend systems:

Beacon Configuration:
- Administrators use tools (e.g., Google’s Beacon Tools app, manufacturer-provided software) to program beacons with desired packet types (e.g., UID + TLM, URL). For EID packets, encryption keys and rotation intervals are set during configuration.
- Beacons are deployed in physical locations (e.g., retail stores, office buildings, factories) and begin broadcasting BLE signals continuously at a configurable interval (100ms–10s).
Device Detection & Data Reception:
- Compatible mobile devices (Android/iOS) scan for BLE signals. When a device enters the beacon’s range (typically 0–50m, depending on signal strength), it detects the Eddystone packet.
- For URL packets: Android devices can resolve the link directly via Google Play Services; iOS devices require a custom app to process the URL.
- For UID packets: The device sends the beacon’s namespace/instance ID to a backend server, which maps the ID to a location or action (e.g., “Namespace ABC, Instance 123 = 1st floor café”).
- For TLM packets: Backend systems collect telemetry data to monitor beacon health and performance.
Action Triggering:
- Based on the received data, the device or backend triggers predefined actions:
  - Display a notification (e.g., “Special offer at this store!”).
  - Open a web page or app (e.g., museum exhibit details).
  - Log beacon location data for asset tracking.
  - Alert administrators to low beacon battery levels.

Eddystone vs. iBeacon

As the two most widely used BLE beacon formats, Eddystone and Apple’s iBeacon differ in key design goals and capabilities:

Feature	Eddystone	iBeacon
Ownership	Open-source (Google), vendor-agnostic	Proprietary (Apple), iOS-focused
Packet Flexibility	Supports 4 packet types (UID/URL/TLM/EID) for diverse use cases	Only supports a single packet type (UUID + Major/Minor IDs)
Cross-Platform Support	Native support for Android and iOS	Optimized for iOS; Android requires custom code for full functionality
Security	EID packet provides encrypted, rotating IDs for privacy	No built-in encryption; static UUIDs are vulnerable to spoofing
Use Case Focus	Proximity marketing, asset tracking, beacon telemetry	Indoor positioning, iOS-only location services
URL Support	Native URL compression and broadcasting	No native URL support; requires backend mapping of UUIDs to links

Applications of Eddystone

1. Retail & Proximity Marketing

Beacons placed in stores broadcast URL packets with promotional offers, product information, or loyalty program links. Customers receive notifications when they are near specific aisles or displays.
UID packets enable foot traffic analytics (e.g., tracking how many customers visit a section and how long they stay).

2. Indoor Positioning & Navigation

Deployed in large venues (malls, airports, hospitals) to power indoor mapping and navigation apps. UID packets are mapped to specific locations, allowing users to find stores, gates, or medical departments without GPS (which is ineffective indoors).

3. Asset Tracking & Management

Used in warehouses, factories, and supply chains to track high-value assets (e.g., tools, pallets, equipment). UID packets uniquely identify each beacon, and backend systems monitor asset location in real time. TLM packets alert managers to low battery or malfunctioning beacons.

4. Smart Cities & Public Services

Beacons in public spaces (parks, transit stations) broadcast URL packets with public transit schedules, event information, or emergency alerts.
EID packets are used for secure tracking of public assets (e.g., streetlights, waste bins) to prevent tampering.

5. Museums & Cultural Institutions

Beacons near exhibits broadcast URL packets with detailed exhibit descriptions, videos, or audio guides. Visitors can access content on their smartphones without needing physical brochures.

Challenges & Limitations

Range Constraints: BLE signals have a limited range (up to 50m in ideal conditions; reduced in crowded or concrete-heavy environments), requiring dense beacon deployment for full coverage.
Device Compatibility: While Eddystone supports iOS, Apple’s Core Bluetooth framework requires custom apps to process packets—unlike Android, which integrates with Google Play Services for seamless detection.
Privacy Concerns: Static UID packets can be used to track user movements if beacons are not properly secured. EID packets mitigate this, but they require additional configuration and backend support.
Battery Life: Although BLE is low-power, beacon battery life depends on broadcast interval (frequent broadcasts drain batteries faster) and environmental factors (temperature, humidity).

Future of Eddystone

Edge Computing Support: New beacon hardware includes edge processing capabilities, allowing beacons to trigger local actions (e.g., activating a sensor) without relying on a backend server.

Integration with IoT Systems: Eddystone beacons are increasingly paired with IoT platforms to enable smart building automation (e.g., triggering lighting or HVAC adjustments when a user enters a room).

Enhanced Security: Adoption of EID packets is growing for privacy-sensitive applications, with improvements to encryption and rotation algorithms to prevent spoofing.