A logistics company is designing an online monitoring dashboard that tracks live telemetry data from delivery vehicles. The solution needs to automatically run custom code whenever new telemetry data arrives in the database and immediately broadcast the updates to connected web browsers without managing underlying servers or paying for idle compute time. Which Azure serverless architecture best meets these requirements?

Azure Functions combined with Azure SignalR Service: ### What Azure Functions and Azure SignalR Service Are **Azure Functions** is a serverless **Function-as-a-Service (FaaS)** platform that allows developers to run event-driven code without provisioning or managing infrastructure. **Azure SignalR Service** is a fully managed cloud service that simplifies adding real-time, two-way web communication (such as WebSockets) to applications, broadcasting live content directly to connected client browsers. ### How It Meets the Requirements - **Event-Driven Execution**: **Azure Functions** responds dynamically to database changes (such as an Azure Cosmos DB change feed or event queue triggers) to execute transformation logic the instant new vehicle telemetry arrives. - **Real-Time Client Broadcasting**: The **SignalR Service output binding** enables the serverless function to push real-time updates directly to thousands of active client dashboard sessions without polling. - **No Idle Costs**: Under serverless consumption plans, compute billing is purely **pay-for-what-you-use**, ensuring the organization is only billed when code executes in response to events. - **Zero Server Management**: Both components are fully managed cloud services that automatically scale out during traffic bursts and scale down to zero when idle. ### Key Advantages and Capabilities - **Pre-built triggers and bindings**: Simplifies integrating data sources like **Azure Event Hubs**, **Azure Cosmos DB**, and **Azure Service Bus**. - **Multi-language support**: Developers can author logic in **C#**, **JavaScript/TypeScript**, **Python**, or **Java**. - **Massive scalability**: Automatically scales to handle millions of simultaneous telemetry messages and connected dashboard users. - **Built-in security**: Integrates natively with authentication providers via **Microsoft Entra ID**. ### Why This Is Optimal Combining **Azure Functions** with **Azure SignalR Service** delivers an end-to-end serverless architecture tailored specifically for event-driven, real-time web scenarios. It eliminates ongoing virtual machine maintenance, ensures sub-second dashboard updates, and minimizes operational expenditure.