It is a fully managed Message Broker service
Protocols: HTTP/HTTPS, AMQP
Service Bus can be used to create Queue similar to Azure Queue
It can also create topics which are queues which can be monitored by multiple subscribers
A subscription acts like a dedicated queue for the subscriber with its own configuration
Supports message ordering FIFO (Needs to be enabled on queue and topic)
Supports Duplicate Detection and Batch Processing
DLQ (Dead-letter Queue)
Capture messages that where not processed in their lifetime and process them accordingly
Azure Service Bus Topic Filters - Azure Service Bus | Microsoft Learn
Pricing Tiers
Basic
Does not support Topics
Standard
Uses “Pay as you go model”
Variable throughput and variable message latency
Supports messages up to 256 KB
Supports auto-scaling
Supports Queue and Topic Partitions
Premium
Pricing and throughput is based on Messaging Units
Requires configuration of scaling rules
Messages up to 1 MB is supported
Supports Availability Zone & Geo-disaster recovery
Does not support Queue and Topic Partitions