The web, mobile, or SPA application registration enables your app to sign in with Azure AD B2C. To enable your app to sign in with Azure AD B2C and call a web API, you need to register two applications in the Azure AD B2C directory. It reads the claims that are encoded in the token (optional). It validates the permissions (scopes) in the token.

It reads the bearer token from the authorization header in the HTTP request. It passes the access token as a bearer token in the authentication header of the HTTP request by using this format: Authorization: Bearer It acquires an access token with the required permissions (scopes) for the web API endpoint. It authenticates users with Azure AD B2C. Token-based authentication ensures that requests to a web API are accompanied by a valid access token. Configure authentication in a sample single-page application (SPA).Configure authentication in a sample ASP.NET Core application.Then, follow the steps in this article to replace the sample web API with your own web API. Prerequisitesīefore you begin, read one of the following articles, which discuss how to configure authentication for apps that call web APIs. After you complete the steps in this article, only users who obtain a valid access token will be authorized to call your web API endpoints.

This article shows you how to enable Azure AD B2C authorization to your web API. To authorize access to a web API, you can serve only requests that include a valid access token that's issued by Azure Active Directory B2C (Azure AD B2C).

Azure b2c login