Realizing Fully Secure Unrestricted ID-Based Ring Signature in the Standard Model Based on HIBE

We describe a secure and unrestricted identity-based ring signature scheme in the standard model. Our construction is provably fully secure in the standard model under static assumptions and is motivated by an existing HIBE scheme. Our observation on the relationship between ID-based ring signatures and HIBE is of interest to researchers in other fields as well. Following the strongest anonymity definition in ring signatures, we define a new level of anonymity for ID-based ring signatures in which the attacker can specify the randomness used in the creation of the user secret key, in addition to the private key generators master key. Our scheme provides unconditional anonymity in this model.