Introduction
Welcome to The Zenoh Book — the definitive guide to the Zenoh protocol.
What is Zenoh?
Zenoh (pronounced zen-oh) is an open protocol that unifies:
- Data in motion — publish/subscribe messaging with location-transparent key expressions
- Data at rest and computations — a location-transparent query/queryable abstraction that enables geo-distributed queries resolved by databases, by on-demand computation, or both
Unlike traditional protocols that address only one tier of the stack, Zenoh works from microcontrollers up to multi-datacenter cloud deployments — with a single coherent API and a 5-byte wire overhead.
Design Goals
Zenoh was designed with five non-negotiable properties:
| Property | Description |
|---|---|
| Wire efficiency | 5-byte minimum overhead; fits smallest embedded payloads |
| Scale up | Scales to internet-wide deployments without re-architecting |
| Scale down | Runs on bare-metal with 2 KB RAM (Zenoh-Pico) |
| Topology freedom | Peer-to-peer, brokered, routed — any mix, no constraints |
| Location transparency | Producers and consumers are fully decoupled; resources move freely |
Why Zenoh?
"I had to do something. I started working on the idea of coming up with a protocol that could work efficiently from the microcontroller up to the data-center, would not have any topological constraints and would provide unified abstraction for dealing with data in movement and data at rest."
— Angelo Corsaro, February 2026
The name Zenoh references the pre-Socratic philosopher Zeno of Elea (known for paradoxes of infinity) and the Stoic founder Zenon of Citium — and doubles as an acronym: Zero Network OverHead.
Who Uses Zenoh?
Zenoh is the official DDS alternative selected by the ROS 2 Technical Steering Committee and is recommended by the ITU for Intelligent Transport Systems. It is adopted by General Motors (uProtocol), Bosch, Foxconn, NXP, Ampere Computing, Google/Intrinsic, and Dexory Robotics, among others.
How to Use This Book
If you're new to Zenoh, start with Getting Started. If you have a specific question, jump directly to the relevant chapter from the sidebar.
All code examples in this book use the Rust API. Bindings for Python, C, C++, Java, and more are documented at zenoh.io.