Digital transactions have permeated almost every sphere of activity in today’s world. This increase in digital transactions has introduced additional and stringent requirements with regard to security and privacy. People reveal lots of personal information by compromising their private credentials during digital interactions. It is imperative that in addition to security of on-line transactions, user credentials must also be safeguarded. This has necessitated the requirement for a rigorous and foolproof credential system with provision for anonymous and revocable identity management system. Biometric system based identity management systems offer advantage over conventional knowledge and possession based systems.
Considerable research has been undertaken in the past to identify newer and reliable biometrics for more efficient and secure identity management. Fusion of multiple biometrics to achieve better results is also an area of active research. However, making biometric credential systems revocable and anonymous without sacrificing efficiency and efficacy of detection, still remains a challenge. This survey paper makes an attempt to give an insight into the approaches that have been made in the direction of multimodal biometric fusion and into the various options that have been explored to make biometric authentication systems revocable and anonymous.