Biblio
Mobile crowd sensing (MCS) is a rapidly developing technique for information collection from the users of mobile devices. This technique deals with participants' personal information such as their identities and locations, thus raising significant security and privacy concerns. Accordingly, anonymous authentication schemes have been widely considered for preserving participants' privacy in MCS. However, mobile devices are easy to lose and vulnerable to device capture attacks, which enables an attacker to extract the private authentication key of a mobile application and to further invade the user's privacy by linking sensed data with the user's identity. To address this issue, we have devised a special anonymous authentication scheme where the authentication request algorithm can be obfuscated into an unintelligible form and thus the authentication key is not explicitly used. This scheme not only achieves authenticity and unlinkability for participants, but also resists impersonation, replay, denial-of-service, man-in-the-middle, collusion, and insider attacks. The scheme's obfuscation algorithm is the first obfuscator for anonymous authentication, and it satisfies the average-case secure virtual black-box property. The scheme also supports batch verification of authentication requests for improving efficiency. Performance evaluations on a workstation and smart phones have indicated that our scheme works efficiently on various devices.
Nowadays, the design of a secure access authentication protocol in heterogeneous networks achieving seamless roaming across radio access technologies for mobile users (MUs) is a major technical challenge. This paper proposes a Distributed Anonymous Authentication (DAA) protocol to resolve the problems of heavy signaling overheads and long signaling delay when authentication is executed in a centralized manner. By applying MUs and point of attachments (PoAs) as group members, the adopted group signature algorithms provide identity verification directly without sharing secrets in advance, which significantly reduces signaling overheads. Moreover, MUs sign messages on behalf of the group, so that anonymity and unlinkability against PoAs are provided and thus privacy is preserved. Performance analysis confirm the advantages of DAA over existing solutions.