What type of identity proofing do questions like "What's your pet's name?" represent?

The type of identity proofing represented by questions such as "What's your pet's name?" falls under knowledge-based authentication. This method relies on information that the user knows and is often used for verifying identity when accessing accounts. Knowledge-based authentication is typically employed in scenarios where a user must provide answers to specific questions that ideally only they would know, thereby proving their identity.

This approach is commonly used during account recovery processes or when accessing sensitive information. While it offers a layer of security, it can also present vulnerabilities, such as the potential for answers to be guessed or publicly obtained.

In contrast, biometric authentication relies on unique physical characteristics, such as fingerprints or facial recognition, rather than knowledge. Two-factor authentication and multi-factor authentication involve a combination of different forms of authentication, typically requiring something the user knows (like a password) along with something they have (like a smartphone for receiving a code) or something they are (like a biometric). These methods enhance security beyond the simple knowledge-based approach, emphasizing the importance of using multiple verification factors for higher security.