Design And Implementation Of LBS Privacy Protection Algorithm In Mobile P2P Network Environment

As the development of wireless communication technology, and GPS, Location-Based Services(LBS) is widely used in recent years. Although providing users with aconvenient serving, LBS gives rise to new security problems. When using the LBS,users have to offer some information of privacy, such as location and query. Therefore,users concern about LBS would reveal their private information. A large number ofalgorithms and solutions have been put forward from many researchers all over theworld. The k-anonimity is the most used privacy-preserving algorithms. Most of thesesolutions are designed with a centralized architecture which collect location informationfrom a third trustworthy party. However, in some the practical application environment,there is difficult to pre-set a trusted third-party.As a result, some researchers begin toresearch the privacy-preserving algorithms of LBS in the mobile peer-to-peer(P2P)network environment. However these solutions only meet the request of k-anonimity,and cloak the spatial position of uses. Further more these algorithms need modeanonymous response time and lead to a great system communication overhead which isdifficult to meet the requirements of the practical application of mobile P2P network.In view of the issues of the current privacy-preserving algorithms for the mobileP2P network, this thesis puts forward a new LBS privacy-preserving algorithm.According to the change of the users’ velocity, the algorithm broadcast the users’location infomation. When requesting service, users can figure out the current locaionfrom the received information to build the anonymous region. After that, we import thetheory of entropy to ask the users’ query be kept uncertainty which can prevent thequery homogeneity attack. The algorithm meets the request of k-anonimity andl-diversity, and cloaks not only the location informatino but also the query. Finally, inorder to against the continuous queries attack, we improve the velocity-based algorithm.When users want to query continuously，they have to use the information of the userswho have the same velocity of them to build the anonymous region. So they can use thesame anonymous set to ask service for many times. The solution can reduce thedifference of the anonymous set from the continuous queries, and reduce the probability of the attack.According to the simulation experiment results, the given algorithms have raised ofcertain level compare with the existing algorithms in the anonymous success rate,system communication overhead and the anonymous response time, showing thesuperiority and effectiveness of the algorithm.