ABSTRACT
Many 21st century challenges require the timely integration of vast amounts of geospatial information through a Geographic Information System (GIS) to address global and regional issues such as emergency response and planning. The timely integration of large amounts of information requires the readiness of a computing infrastructure with the following characteristics: sufcient computing capabilities, minimized energy cost, fast response, and wide accessibility to the public. Traditional GIS software, such as ArcGIS, is operated on desktops and local servers, and is focused on single users, mostly GIS experts. It requires the installation and maintenance of both hardware and software, and lacks the ability to support the needs of largescale concurrent access. Cloud computing provides the computing capability to build and deploy GIS as a service, which can be referred to as cloud-enabled GIS or Cloud GIS (Mann 2011). The emergence of Cloud GIS is motivated by the need to establish new maintenance, usage, and billing modes which can address the existing computing issues and satisfy a broader user base. The technologies and architecture that cloud computing can offer are key areas of research and development for GIS solutions (Kouyoumjian 2010). New GIS solutions, such as the ArcGIS Online (introduced in Section 7.2.1), have been provided by delivering GIS as cloud
services (Bhat et al. 2011). Cloud GIS can provide users with (1) no installation and maintenance of software, (2) unlimited computing resources and storage space, and (3) on-demand services. Additionally, Cloud GIS extends the application scope of GIS from geography to various social and business elds.
