A User-Centric Protocol for Conditional Anonymity Revocation

Conditional Privacy Using Re-encryption

“…An ARM may decrypt the escrowed information, even when the attached conditions remain unfulfilled: the attached conditions are not enforceable except through the 'trust' that the ARM can properly and honestly assess the fulfillment of the attached conditions. One attempt to address such a trust problem is proposed in [14] whereby PCS is combined with universal custodian-hiding verifiable encryption (UCHVE) -we henceforth call this approach UCHVE-PCS. The UCHVE-PCS approach in [14] distributes the trust between the ARM and a set of referees.…”

“…One attempt to address such a trust problem is proposed in [14] whereby PCS is combined with universal custodian-hiding verifiable encryption (UCHVE) -we henceforth call this approach UCHVE-PCS. The UCHVE-PCS approach in [14] distributes the trust between the ARM and a set of referees. However, the UCHVE-PCS approach [14] has accountability and efficiency problems.…”

“…The UCHVE-PCS approach in [14] distributes the trust between the ARM and a set of referees. However, the UCHVE-PCS approach [14] has accountability and efficiency problems. If A's private information is misused, it is not clear as to who is responsible for such misuse because the UCHVE-PCS approach allows any one of the referees, ARM or B to learn A's private information.…”

“…If A's private information is misused, it is not clear as to who is responsible for such misuse because the UCHVE-PCS approach allows any one of the referees, ARM or B to learn A's private information. In addition, UCHVE-PCS [14] suffers from severe computational inefficiency due to the large number of online modular exponentiations that need to be performed. This paper proposes a new mechanism to improve the UCHVE-PCS approach [14] by using an existing proxy re-encryption (PRE) scheme proposed by Ateniese et al (2006) [1].…”

“…In addition, UCHVE-PCS [14] suffers from severe computational inefficiency due to the large number of online modular exponentiations that need to be performed. This paper proposes a new mechanism to improve the UCHVE-PCS approach [14] by using an existing proxy re-encryption (PRE) scheme proposed by Ateniese et al (2006) [1]. PRE has been used in the area of secure file storage, access control, and delegations.…”