Operation canceled: Microsoft Graph .NET SDK CancellationToken propagation

Cancellation behavior in Microsoft Graph SDK

When utilizing the Microsoft Graph .NET SDK (v5.0+), developers can pass a CancellationToken to asynchronous methods to manage request lifecycles. While the SDK is designed to throw an OperationCanceledException when a token is triggered, there is uncertainty regarding how this cancellation propagates through the underlying HttpClient and downstream Microsoft 365 services.

Backend propagation and timeouts

The default HttpClient configuration typically implements a 100-second timeout. However, when a request is handed off to backend services—such as Exchange Online or Azure AD—it is unclear if the cancellation of the client-side token effectively terminates the processing on the server side or if the backend continues to execute the operation until a timeout occurs.

This creates a gap in understanding whether client-side cancellation truly reduces backend load or simply ignores the eventual response.

• Does the CancellationToken reliably trigger an immediate abort of the HTTP request in the underlying HttpClient?
• Is there documented behavior confirming that cancellation tokens propagate to downstream M365 service providers to stop backend processing?