Challenge–response authentication
Challenge–response authentication is a way to help make sure that your identity is securely verified when accessing an account. When challenge–response authentication is used, you will be asked to provide a response to a question or enter a code that only you know. The challenge (question or code) ensures that you are the true owner of your account. For example, imagine you want to log in to a website that uses challenge–response authentication. They may send you a code via text message or email that you need to enter correctly in order to access your account.
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