A Survey of Hard Core Functions
María Isabel González Vasco, Mats Näslund · Birkhäuser Basel eBooks · 2001
The security of public key protocols relies nowadays on the use of one-way functions. However, even assuming a certain function f(x) is hard enough to invert, we should always keep in mind the fact that some information may leak through. A function b(x) that does not leak in this way is said to be a hard core for f ; given f(x) , b(x) cannot even be computationally distinguished from a random string. In this survey, we review what is known in this area, both from a more theoretical point of view and also for ‘practical’ choices of f such as RSA.