
8
Big Data: Storage, Sharing, and Security
objects, and several systems have emerged over the past few years to fill this gap. Well-
known systems and prototypes include HadoopGIS [8–10], SpatialHadoop [16,17], Parallel
Secondo [20,21], and GIS tools for Hadoop [4,30]. These systems are based on the open source
implementation of MapReduce—Hadoop, and provides similar analytics functionality. How-
ever, they differ in implementation details and architecture: HadoopGIS and SpatialHadoop
are pure MapReduce-based query evaluation systems; Parallel Secondo is a hybrid system
that combines a database engine with MapReduce; and GIS tools for Hadoop is a