Qpid

Apache Qpid is an open-source messaging framework developed under the Apache Software Foundation. It provides messaging products that implement the AMQP protocol to enable asynchronous communication between applications and services. The project includes broker implementations, client libraries, and tooling for building distributed systems.

The project includes broker software, such as traditional message brokers, and client libraries for languages including C++, Java, and Python, allowing applications to connect to brokers and exchange messages. The Proton library offers AMQP 1.0 client APIs across languages, while the Qpid Dispatch Router provides a lightweight router that scales messaging in large deployments.

Architecture and design: Qpid emphasizes modular components that can be mixed and matched; brokers manage queues and routing, clients publish and consume messages, and routers route messages between endpoints in dynamic topologies. It supports features such as durable messaging, transactions, and flow control to ensure reliability and performance in distributed environments.

History and status: Apache Qpid originated under the Apache Software Foundation as an implementation of AMQP. It has evolved through community contributions and is maintained with releases that include components such as the C++ broker, Java clients, and the Proton library. The project remains part of the ASF ecosystem and is available as an open-source AMQP messaging solution.

Licensing and availability: Apache Qpid is released under the Apache License 2.0 and is available through ASF repositories and distribution channels, with ongoing community support.