Knowledge-based authentication, commonly referred to as KBA, is a method of authentication which seeks to prove the identity of someone accessing a service such as a financial institution or website. As the name suggests, KBA requires the knowledge of private information from the individual to prove that the person providing the identity information is the owner of the identity. There are two types of KBA: static KBA, which is based on a pre-agreed set of shared secrets, and dynamic KBA, which is based on questions generated from a wider base of personal information.