Exam AZ-305 topic 4 question 79 discussion

C. Azure Service Bus queues with sessions enabled Explanation: Azure Service Bus supports a FIFO pattern through the use of sessions. A session is a sequence of ordered messages. All messages in a session are handled in the order they arrive. This ensures that messages are processed in the order they were added to the queue. Options A and D are incorrect because Azure Storage queues do not natively support the First In, First Out (FIFO) pattern. There are no such features as custom metadata setting or stored access policy that can establish FIFO in Azure Storage queues. Option B is incorrect because while partitioning in Azure Service Bus can improve performance by spreading the load across multiple message brokers and stores, it doesn't enforce FIFO ordering across partitions. FIFO ordering is maintained within a partition, but not across partitions. Hence, for strict FIFO, you would not want to enable partitioning, you would want to use sessions.

C is the answer. https://learn.microsoft.com/en-us/azure/service-bus-messaging/message-sessions Azure Service Bus sessions enable joint and ordered handling of unbounded sequences of related messages. Sessions can be used in first in, first out (FIFO) and request-response patterns. This article shows how to use sessions to implement these patterns when using Service Bus.

Given Answer C is correct Service Bus queues are part of a broader Azure messaging infrastructure that supports queuing, publish/subscribe, and more advanced integration patterns. They're designed to integrate applications or application components that might span multiple communication protocols, data contracts, trust domains, or network environments Advanced messaging features like first-in and first-out (FIFO), batching/sessions, transactions, dead-lettering, temporal control, routing and filtering, and duplicate detection

The wording of the question is slightly misleading. A queue has by default a FIFO mechanism to send and receive messages. In this context the user wants to create his own CUSTOM order. To do this, sessions are used to mark the messages that should be received first, then second, etc, so what is known as FIFO is broken. This article helps with a visualization of the process: https://learn.microsoft.com/en-us/azure/service-bus-messaging/message-sessions#session-features A session is like a subqueue.

"Azure Service Bus queues with sessions enabled" As a solution architect/developer, you should consider using Service Bus queues when your solution requires the queue to provide a guaranteed first-in-first-out (FIFO) ordered delivery. https://learn.microsoft.com/en-us/azure/service-bus-messaging/service-bus-azure-and-service-bus-queues-compared-contrasted#consider-using-service-bus-queues Sessions can be used in first in, first out (FIFO) and request-response patterns. https://learn.microsoft.com/en-us/azure/service-bus-messaging/message-sessions

C. Azure Service Bus queues with sessions enabled. Azure Service Bus queues with sessions enabled ensure a FIFO pattern by allowing messages to be processed in order, and messages are processed by a single receiver instance.

C. Azure Service Bus queues with sessions enabled

C is a go and recommended from what i can see. Service Bus queues ordering guarantee Yes - First-In-First-Out (FIFO) (by using message sessions)

Only Service Bus quarantees FIFO and you need to use Sessions for this. https://learn.microsoft.com/en-us/azure/service-bus-messaging/service-bus-azure-and-service-bus-queues-compared-contrasted

C: Sessions: Enabling sessions on an Azure Service Bus queue allows for grouping of related messages together. This can be useful if you need to ensure that messages related to a specific session or conversation are processed in order. With sessions, you can also allow multiple consumers to process messages from the same session in parallel, which can improve the overall throughput of the queue. This is useful if you expect to have a large number of conversations and need to scale out the processing of those messages.