Group relational privacy protection on time-constrained point of interests

1 Introduction With the rapid development of mobile networks,locationbased services has become popular in the daily lives of people.The service providers can recommend the profitable services to persons through mining the frequent interests or places of persons.However,one aspect is that the historical data on Internet can easily cause the leakage of user-relationship privacy,another aspect is that the historical interests of person are always bound to time.Therefore,this paper devotes to study a privacy protection method on time-constrained point of interests(PoIs)based on the group relationships of users.