
Explanation:

Scenario: Shipping Function app: Implement secure function endpoints by using app-level security and include Azure Active Directory (Azure AD).
Box 1: Function
Box 2: JSON based Token (JWT)
Azure AD uses JSON based tokens (JWTs) that contain claims
Box 3: HTTP
How a web app delegates sign-in to Azure AD and obtains a token
User authentication happens via the browser. The OpenID protocol uses standard HTTP protocol messages.
References:
https://docs.microsoft.com/en-us/azure/active-directory/develop/authentication-scenarios