Apache Qpid Broker-J vs EMQX

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.

EMQX is an MQTT messaging platform for connecting, moving, and processing IoT business data in real time. EMQX Enterprise combines publish/subscribe messaging with durable message queuing, while a SQL-based Rule Engine and visual Flow Designer support filtering, transforming, enriching, and routing data. The platform supports MQTT and protocols or gateways including QUIC, CoAP, STOMP, and LwM2M; its listed protocols also include MQTT-SN, OCPP, GB/T 32960, JT/T 808, and NATS. EMQX says a cluster can handle up to 100 million concurrent MQTT connections and lists more than 50 native integrations. Security features include TLS/mTLS, X.509 authentication, access controls, and audit logs. Deployment options include Docker, a Kubernetes Operator, and installation packages, with macOS and Linux packages listed. Plans include free Serverless and Dedicated Flex starting at $234 per month, with a 14-day trial listed for Dedicated Flex. Serverless has limits including 1,000 sessions, 1,000 TPS, and a 1 MB message size.