# CybusMQ CybusMQ is a robust MQTT broker tailored for industrial applications, offering support for both MQTT 5 and MQTT 3.1.1 protocols. It serves as the central message broker within the Connectware ecosystem, facilitating efficient data exchange and inter-service communication. ## Key Features * **Industrial-grade stability and scalability**: Engineered to withstand the demands of industrial environments, ensuring reliable performance under high-load conditions. See [Scaling the Broker Cluster](/broker/cybusmq/operations/scaling-the-broker-cluster.md) for scaling strategies. * **Protocol support**: Offers services for MQTT, secure MQTT over TLS (MQTTS), and MQTT over WebSockets, providing flexibility in communication methods. See [Collocated One-way and Mutual TLS](/broker/cybusmq/configuration/collocated-tls-configuration.md) for TLS configuration details. * **Metrics exposure**: Exposes comprehensive usage and performance metrics for integration with monitoring systems like Prometheus and Grafana. See [Monitoring & Analytics](/broker/cybusmq/configuration/monitoring-and-analytics.md) for details. * **Authentication delegation**: Employs webhooks to delegate authentication processes to the Auth-Server, ensuring secure access control. See [Self-Refreshing Webhooks Cache](/broker/cybusmq/configuration/self-refreshing-webhooks-cache.md) for implementation details. ## Technical Specifications * **Foundation**: CybusMQ is built on VerneMQ, a high-performance distributed MQTT message broker. This foundation provides robust messaging capabilities across distributed systems. * **Technology stack**: CybusMQ is written in Erlang, a language optimized for concurrent operations and fault tolerance. The Erlang/OTP virtual machine uses preemptive scheduling, delivering consistent low latency for real-time applications at scale. * **Configuration**: CybusMQ can be configured through environment variables and configuration files. See [Configuration Options](/broker/cybusmq/configuration.md) and [Environment Variables](/broker/cybusmq/environment-variables.md) for available settings. For a detailed comparison between CybusMQ and VerneMQ, see [Feature Overview](#feature-overview). ## Feature Overview Comparison between CybusMQ and VerneMQ, highlighting the advantages of CybusMQ. | Feature | CybusMQ | VerneMQ | CybusMQ Advantage | | ------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------- | ------------------------------------------------------------------- | | **Performance & Scalability** | | | | | [Message Deduplication for Overlapping Subscriptions](/broker/cybusmq/configuration/duplicate-message-delivery.md) | Configurable single/multiple delivery | Multiple delivery | Reduced network overhead and simplified client implementation | | [Synchronous SUBSCRIBE Handling](/broker/cybusmq/configuration/synchronous-subscribe-handling.md) | Synchronous processing at cluster level | Asynchronous processing | Better control over subscription acknowledgments | | **Clustering & High Availability** | | | | | [Continuous Cluster Discovery in Kubernetes](/broker/cybusmq/configuration/continuous-cluster-discovery-in-kubernetes.md) | Periodic discovery attempts at runtime | Single cluster discovery attempt at startup | Seamless scaling and node management in cloud environments | | [Clustering Connection Improvements](/broker/cybusmq/configuration/clustering-connections.md) | Detached queue and sender tolerating network instabilities, multithreaded routing on receive | Single sender/queue sensitive to network delays, single-threaded routing on receive | Better cluster stability and performance | | [Metadata Store Improvements](/broker/cybusmq/configuration/metadata-store.md) | Improved data structures, optimizations, faster initial sync | Upscale is slow and memory-intensive for aged replicas | Faster initial sync when cluster is upscaled, better memory profile | | **Security** | | | | | [Collocated One-way and Mutual TLS](/broker/cybusmq/configuration/collocated-tls-configuration.md) | Flexible TLS configuration options | Separate listeners needed for one-way and mutual TLS | Simplified client configuration and network maintenance | | [Self-Refreshing Webhooks Cache](/broker/cybusmq/configuration/self-refreshing-webhooks-cache.md) | Detached authentication updates from publish processing | Trial and error expiration strategy during publish processing | No delayed message forwarding due to authentication | --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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