Indexing the Past, Present and Future Positions of Moving Objects on Fixed Networks

The development of a spatio-temporal access method suitable for objects moving on fixed networks is a very attractive challenge due to a large number of applications dealing with this type of objects. In this paper, we propose a novel indexing technique named PPFI which consists of a 2D R*-tree, a forest of 1D R*-tree, and a hash structure. PPFI not only supports queries related to the past positions or trajectories of moving objects on fixed networks, but also provides an efficient update mechanism, stores current positions and supports predictive query. The performance study, comparing this access method with FNR-Tree, STR-Tree under range query and trajectory query, shows that PPFI outperforms them.