Overview of spatial index in the cloud storage

With the progress of WebGIS in the cloud storage environment, it is the foundation and a key technology of WebGIS to build highly efficient spatial index. The requirements of cloud storage and the development of spatial index structures and algorithms were analyzed, and the research were classified as single master metadata server, cluster metadata server and semantic sharing, the index of small files in one data block model were validated with HDFS. At last, the future works were discussed.