Traditional and Emerging Data Protection Methods

This chapter treats data protection mechanisms not covered in other parts of the book and examines whether they can be used to protect biometric templates in verification and identification applications. The considered mechanisms include cryptographic, non-cryptographic, and hardware-based solutions, which are divided into traditional and emerging mechanism categories. The chapter demonstrates that many of these protection mechanisms are not suitable as solutions for Biometric Template Protection (BTP). For example, cryptographic constructions such as encryption schemes and hash functions possess strong security properties; however, the strong obfuscation they achieve by erasing all patterns from the input is the reason they are not suitable for working with noisy biometric data. We also discuss potential solutions that rely on distributed databases, smart cards, and trusted execution environments (TEEs) and only consider TEE as conceptually suitable for achieving the necessary security guarantees for protecting biometric templates in verification and identification applications.