Testing this simple ASP.NET MVC application, you can enter the user credentials (Figure 1).

Figure 1: Log On form

If your information is correct, you’ll see a textbox appeared asking you for a verification code to enter. At the same time, code is generated and set to the mobile number of the user (Figure 2).

Figure 2: Text message received

You receive the number and can enter that to verify the user (Figure 3).

Figure 3: Enter verification code

And you’ll be signed into the site! Next time, if you visit the page with the same IP address and browser, you will automatically log in without dealing with the verification code.