A user collaboration privacy protection scheme with threshold scheme and smart contract

Recently, the revolution of 5G networks has promoted a wide application of wireless technology, and then followed with the prosperity of Location-Based Service (LBS). However, an intricate problem called privacy violation still restricts the development of this type of service. To preserve users’ privacy, some privacy preservation strategies had been proposed. As an efficient framework used for protecting personal privacy, users’ collaboration is mainly proposed for dealing with the issue of service bottleneck and the issue of attack focus. However, there are still several challenges far from being perfectly solved, such as the collusion attacks as well as the willingness of collaborative users. Therefore, to address these challenges, in this paper, based on the conception of information division and user’s incentive, a (t,n) smart contract privacy preservation scheme short for (t,n) SCPPS is proposed. In this scheme, the query information is encrypted and split by (t, n) threshold scheme, so the collaborative users will be difficult to learn anything about the initiator, and the collusion will be difficult to constitute the integral query without t users colluding with each other. On the other hand, the combination of (t, n) threshold scheme and smart contract further provide incentive competition, as just the earliest collaborative users that submit the partition information and get the corresponding feedback will obtain the incentive. At last, the security analyses were given, and then tests of users’ granularity and locations difference in the continuous query in the real environment. Furthermore, simulation experiments are conducted to demonstrate the effectiveness of the proposed scheme, and the experimental verification is executed using two different types of datasets. Thus, compared with other similar schemes, the results with brief explanations about reasons can further demonstrate the superiority of the proposed scheme.