Introduction

Crossbar.io is an open source networking platform for distributed and microservice applications. It implements the open Web Application Messaging Protocol (WAMP), is feature rich, scalable, robust and secure.

What is Crossbar.io?

Crossbar.io is a WAMP router that provides:

  • Publish/Subscribe (PubSub) messaging for real-time notifications

  • Remote Procedure Calls (RPC) for request/response patterns

  • Routed RPC for decoupled distributed systems

  • Pattern-based routing for flexible message targeting

Key Features

WAMP Router

Full implementation of the WAMP protocol for both Basic and Advanced Profiles

Multi-Transport

Support for WebSocket, RawSocket, and HTTP/Long-Poll transports

Authentication

Multiple authentication methods including WAMP-CRA, Ticket, TLS client certificates, Cookie-based, and Anonymous

Authorization

Fine-grained, URI pattern-based authorization for all WAMP operations

Web Services

Built-in static file serving, reverse proxy, CGI, and more

MQTT Bridge

Protocol bridging to MQTT for IoT device integration

Why Crossbar.io?

  • Open Source: Apache 2.0 licensed

  • Production Ready: Battle-tested in production deployments

  • Scalable: Horizontal scaling with router clustering

  • Secure: TLS/SSL, end-to-end encryption support

  • Flexible: Extensive configuration options

Getting Started

New to Crossbar.io? Start with:

  1. Installation - Get Crossbar.io installed

  2. Getting Started - Your first WAMP application

  3. Basic Concepts - Understanding WAMP messaging

Note

Crossbar.io builds on Autobahn|Python for WebSocket and WAMP protocol implementation.