Messaging or Queueing

Messaging and Queueing are related, but they solve different problems.

Choose Messaging when

• one event should fan out to multiple handlers
• producers should not care which consumers react
• the model is event-driven and publish/subscribe oriented
• integration or side effects should be loosely coupled

For details, see Messaging.

Choose Queueing when

• one work item should be handled by one logical consumer
• retries, waiting-for-handler behavior, or durable work dispatch matter
• background work needs operational visibility
• the model is work ownership, not event fan-out

For details, see Queueing.

Comparison

Concern	Messaging	Queueing
Delivery style	Publish/subscribe	Single-consumer work dispatch
Typical fan-out	One-to-many	One-to-one
Primary use	Events and reactions	Background work items
Consumer model	Multiple handlers may react	One handler owns one message type
Operational focus	Event propagation	Work processing and queue control

Decision rule

Use Messaging when something happened.

Use Queueing when something needs to be processed.