On the Black-Box Separation Between Ring Signatures and Public Key Encryptions

ePrint Report: On the Black-Box Separation Between Ring Signatures and Public Key Encryptions

Kyosuke Yamashita, Keisuke Hara

In this paper, we show that it is impossible to construct a public key encryption scheme (PKE) from a ring signature scheme in a black-box fashion in the standard model. Such an impossibility is highly non-trivial because, to the best of our knowledge, known generic constructions of ring signature scheme are based on public key cryptosystems or in the random oracle model. Technically, …

box encryption eprint report fashion key public public key report ring signature signatures standard