Apache Qpid Broker-J vs Eclipse Amlen

Apache Qpid Broker-J is free, open-source Java message-broker software for self-hosted deployments. It stores, routes and forwards messages using AMQP, supporting versions 0-8, 0-9, 0-9-1, 0-10 and 1.0, plus AMQP over WebSockets. Administration is available through REST, AMQP Management and a web console. Routing and queue features include header-based routing, message groups, server-side selectors, dead-letter queues, and last-value, priority and sorted queues. Pluggable persistence supports Derby, SQL and BDB stores. Listed operational features include high availability, producer flow control and flow to disk. Authentication can use LDAP, Kerberos, OAuth2 or SSL client certificates; access control lists and SSL secure connections are supported. The listed current release is 10.1.1, with source archives and tar.gz or zip binaries. Installation documentation covers Windows and UNIX systems. The project uses Apache License 2.0.

Eclipse Amlen is a self-hosted MQTT server for IoT and web messaging. It supports MQTT versions 3 through 5 over TCP/IP and WebSockets, plus JMS, and can convert messages between MQTT and JMS. A protocol plug-in SDK lets users add other protocols, including options for legacy sensors that cannot use MQTT. The Amlen Bridge forwards MQTT messages to another MQTT server or IBM Event Streams for IBM Cloud, with filtering, topic mapping, multiple forwarders, and REST API configuration and monitoring. Security controls include TLS profiles, user ID and password authentication against a configured LDAP server, and policy-based authorization for connections, topics, subscriptions, and queues. Administrators can manage message hubs and endpoints through a WebUI or REST Administration APIs. Supported client platforms include C, Java, Android, iOS, and JavaScript. Server and WebUI downloads are listed for RHEL and AlmaLinux 8, 9, and 10. The free software has configurable delivery guarantees. One limitation is that Amlen supports a single LDAP server connection, so users and groups must be provided through that server.