Research On Privacy-preserving Secure Protocols

Identity privacy is an important security requirement in modern society. Withoutprivacy-preserving, user sensitive context information will be easily disclosed, throughwhich adversaries can learn users’ movement route, habit or even beliefs, etc.To address this issue, we propose four privacy-preserving schemes for differentapplication systems. The main contributions of this dissertation can be summarized asfollows:First, we propose a privacy-preserving acceleration authentication protocol formobile pay-TV systems. It is highly probable that many requests for the same service(popular/hot videos) arrive at the service provider in a short period of time or evensimultaneously in a pay-TV system. In conventional schemes, for non-repudiation ofcommunication, the service provider verifies each service request signed by subscribersone by one, which results in a high computation burden and long delay. Instead, wepropose an efficient privacy-preserving authentication mechanism for mobile pay-TVsystems. The mechanism adopts batch verification technique, allowing the service toverify multiple requests from different subscribers in a batch manner instead of one byone. In addition, a hand-off authentication mechanism with privacy-preserving based onproxy signature cryptography is also proposed to support mobile pay-TV systems. Withthe proxy signature technique, the communication is only between a subscriber and anew transmitter while the head end system is no longer involved during hand-off.Simulation results show that even in the case of high bogus request ratio (p=25%),batch verification still excels individual verification in performance. Moreover, theproposed protocol only requires point multiplication operations on subscribers.Therefore, this scheme enjoys computation and communication efficiency comparedwith the existing schemes.Second, an anonymous data aggregation scheme is proposed for smart grid systems.By integrating the traditional grid with the advanced communication and informationtechnologies, smart grid can provide a reliable and efficient energy service for ourmodern society. Data aggregation plays an important role in evaluating the currentenergy usage information of consumer domains, based on which the operation centercan accommodate distributed power sources to maximize the utilization efficiency.However, it also incurs a potential risk to the consumer privacy. In this dissertation, wepropose an anonymous multi-dimensional data aggregation for smart grid systems. With the proposed scheme, the operation center can compute both additive and non-additiveaggregation functions over the collected reports from consumers. The computation costof each consumer is independent of the number of collected data types. In addition, byusing the batch verification technique, the operation center’s computation cost can besignificantly reduced. The security analysis demonstrates that the proposed scheme canachieve identity privacy preserving, data authentication, and confidentiality.Third, we present an efficient anonymous message authentication scheme forvehicular ad hoc networks. By using identity-based sign-cryption technique, a vehicularuser can first authenticate with a region center to obtain a group signature key material,where the group is managed by the region center. Then, the user can employ the keymaterial to sign a message and broadcast it into the network. Other vehicular users candirectly check the signature without revocation verification. In addition, the used groupsignature supports batch verification, which significantly reduces the verificationoverhead. Compared with the existing schemes, the proposed scheme can achieveforward secure revocation.Last, a secure data sharing for dynamic groups in cloud computing is proposed.With the character of low maintenance, cloud computing provides an economical andefficient solution for sharing group resource among cloud users. Unfortunately, sharingdata in a multi-owner manner while preserving data and identity privacy from anuntrusted cloud is still a challenging issue, due to the frequent change of themembership. We propose a secure multi-owner data sharing scheme, named Mona, fordynamic groups in the cloud. By leveraging group signature and dynamic broadcastencryption techniques, any cloud user can anonymously share data with others.Meanwhile, the storage overhead and encryption computation cost of our scheme areindependent with the number of revoked users. In addition, we analyze the security ofour scheme with rigorous proofs, and demonstrate the efficiency of our scheme inexperiments.