Resources / Azure Azure Messaging Component Map Last updated: September 03, 2026 messaging azure event-driven service-bus event-hubs event-grid practical Related guides Azure Service Bus for System Architects Azure Event Hubs for System Architects Azure Event Grid for System Architects Azure Logic Apps & Durable Functions The Entities Inside Each Broker The routing entities inside Azure Service Bus, Event Hubs and Event Grid Three bands showing the internal components of each broker: a Service Bus topic fanning into filtered subscriptions each with its own dead-letter queue, Event Hubs partitions as append-only logs with independent consumer group offsets, and Event Grid event subscriptions filtering before pushing to handlers. SERVICE BUS · A TOPIC FANS OUT INTO INDEPENDENT SUBSCRIPTIONS topics need Standard+ Producer NAMESPACE Topic Subscription filter: subject Subscription filter: event type DLQ per entity Competing one wins the lock EVENT HUBS · PARTITIONS ARE LOGS, CONSUMER GROUPS HOLD OFFSETS 2+ consumer groups need Standard+ Producer EVENT HUB Partition 0 · ordered, append-only Partition 1 · ordered, append-only Partition 2 · ordered, append-only analytics alerts group: analytics behind, at its offset group: alerts same events, later Capture to Storage partition key EVENT GRID · SUBSCRIPTIONS FILTER, THEN IT PUSHES pull delivery needs a Standard namespace Event source a resource Topic system or custom Event subscription filter: subject prefix Event subscription filter: event type Functions validation handled Webhook Logic Apps, Automation dead-letter to Storage Dead-lettering is a different mechanism in each: a sub-queue in Service Bus, a Storage container in Event Grid, and nothing at all in Event Hubs, where retention alone drops an event. ✗ a blob container is never an Event Grid handler, only its dead-letter destination Found this useful? Share it: Share on LinkedIn
