Fingerprint template protection scheme based on partial minutiae patterns: a comprehensive non-invertibility analysis

A crucial property of an effective fingerprint template protection scheme is non-invertibility, which ensures that the original fingerprint template cannot be recovered from its secured counterpart. Since it is extremely difficult to design a function that achieves a high degree of non-invertibility, it is unsafe to use an entire fingerprint template as the input to any such function. Most existing fingerprint template protection mechanisms, however, do exactly this. One scheme that stands apart from the rest, in that its protected template originates from only a small portion of the minutiae template, is a new fingerprint construct based on partial minutiae patterns. This paper presents a comprehensive analysis of the non-invertibility of this scheme. It is found that the new fingerprint construct has extremely strong non-invertibility and good resistance to a Record Multiplicity Attack in practice. We also propose a modification to improve the method's resistance to this type of attack.