Cloud Computing: Overview and Research Issues

The computational world has become very large and complex. Cloud is an emerging technology in the world of Information Technology. Cloud computing offers IT capabilities as services. Cloud based services are on demand, scalable, device independent and reliable. Cloud computing is built on the virtualization concept. Virtualization separates hardware from software and has benefits of server consolidation and live migration. In this paper we present an overview of cloud computing and also describe about its key technology "virtualization". We are also presenting research challenges in cloud computing.