supported by the National Natural Science Foundation of China(Grant Nos.61976032 and 62002039);the GenReral Scientific Research Project of Liaoning(No.LJKZ0063).
1 Introduction The k-NN(k Nearest Neighbors)searching problem on road network constitutes a crucial aspect of location-oriented services,which has boasted the practical implications.
support by the National Key R&D Program of China(No.2020YFB1005900);the National Natural Science Foundation of China(Grant Nos.62172216,62032025,62071222,U20A201092);the Key R&D Program of Guangdong Province(No.2020B0101090002);the Natural Science Foundation of Jiangsu Province(No.BK20211180,BK20200418);the Research Fund of Guangxi Key Laboratory of Trusted Software(No.KX202034);JSPS Postdoctoral Fellowships for Research in Japan(No.P21073).
Secure k-Nearest Neighbor(k-NN)query aims to find k nearest data of a given query from an encrypted database in a cloud server without revealing privacy to the untrusted cloud and has wide applications in many areas,s...