Answer:   The passport authentication process uses Microsoft's passport service to authenticate users and to describe the authentication process in simple terms-
For Example: “In the passport authentication process, an application first looks for the encrypted authentication cookie. If the user is already signed into the passport, the application considers them as authenticated. If the application does not find the passport cookie, it redirects the user to the passport login page. When the user logs in, the passport service authenticates the details, stores the authentication credentials on the user's machine and redirects them to the requested web page.”