AZ-900 Describe Azure architecture and services Practice Question

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

• ✗

  Azure Service Bus

  Why it's wrong here

  Azure Service Bus is a fully managed enterprise message broker that decouples applications using queues and topics, enabling reliable FIFO ordering, sessions, transactions, and dead-lettering for backend integration. It is designed to deliver messages between services or applications, not to route notifications through platform-specific push services (APNs, FCM, WNS). A mobile push notification requires device registration and direct integration with each platform's notification gateway, which Service Bus does not provide, so it cannot be used to send cross-platform push notifications.

• ✗

  Azure Event Grid

  Why it's wrong here

  Azure Event Grid is a serverless event routing service that reacts to state changes in Azure resources or custom events and delivers them to subscribers like Azure Functions, webhooks, or Logic Apps. It is optimized for high-throughput discrete events (e.g., blob created, resource deleted) and uses a publish-subscribe model with event filtering. Event Grid does not manage device tokens, registrations, or platform-specific send logic; it simply forwards event payloads, so it is unsuitable for delivering personalized push notifications to mobile devices.

• ✓

  Azure Notification Hubs

  Why this is correct

  Azure Notification Hubs is a dedicated push notification engine that abstracts the complexities of multiple Platform Notification Systems (PNS) including APNs, FCM, and WNS. It manages device registrations, handles token expiry and retries, and provides a single API to send notifications to iOS, Android, and Windows devices. With template support, you can tailor message payloads per platform without altering your backend logic, making it the correct service for cross-platform mobile push notifications.

• ✗

  Azure Communication Services

  Why it's wrong here

  Azure Communication Services (ACS) is a comprehensive platform for integrating communication capabilities like voice calls, video, chat, SMS, and email into applications. While ACS has a Chat feature that can send chat-specific push notifications to mobile users, it is not a generalized push notification hub for targeting arbitrary app users across all platforms. Its primary purpose is real-time multi-channel communication, not managing device registrations and delivering broadcast or segmented push notifications to Apple, Google, and Microsoft push services.