A scheme for general group oriented ID-based cryptosystems is proposed. This scheme allows an authorized subset in the general access structure to cooperatively decrypt the cipher...
Group signature schemes are cryptographic systems that provide revocable anonymity for signers. We propose a group signature scheme with constant-size public key and signature leng...
We present the first efficient group signature scheme that is provably secure without random oracles. We achieve this result by combining provably secure hierarchical signatures i...
Secure and reliable group communication is an increasingly active research area by growing popularity in group-oriented and collaborative application. One of the important challeng...
Sangwon Lee, Yongdae Kim, Kwangjo Kim, DaeHyun Ryu
We present a family of verifiable random functions which are provably secure for exponentially-large input spaces under a non-interactive complexity assumption. Prior construction...