Abstract: To solve the problem that the traditional location services anonymity model takes a lot of time to produce anonymous region,the quasi real-time cloak model (QR-TCM) was established．The model proposes a privacy protection method called clock rotation cloak algorithm (CRCA)．After comprehensive analysis of the reasons that influence the anonymity,a model that can solve the users’ service delayed and the method of measuring the quality of service were proposed．The experiment uses the standard data sets,and measures the QR-TCM model with multiple dimensions such as the response time and the degree of privacy．The experiment results confirm that the method is suitable for continuous query location privacy protection,and can effectively protect the user’s privacy and offer fast service.

Key words: Location-based services,Privacy protecting,K-anonymity,K-means,Quality guarantee