Brief Review on Cloud Computing

Cloud Computing has become a scalable services consumption and delivery platform in the field of Services Co mputing. The technical foundations of Cloud Computing include Service-Oriented Architecture (SOA) and Virtualizations o f hardware and software. Cloud computing is the development of parallel computing, distributed computing, grid computing and virtualization technologies which define the shape of a new era. Cloud computing is an emerging model of business com puting. In this paper, we explore the concept of cloud architecture and compares cloud computing with grid computing. We also address the characteristics and applications of several popular cloud computing platforms. In this paper, we aim to pinp oint the challenges and issues of cloud computing. We identified several challenges from the cloud computing adoption pers pective and we also highlighted the cloud interoperability issue that deserves substantial further research and development. However, security and privacy issues present a strong barrier for users to adapt into cloud computing systems. In this paper, we investigate several cloud computing system providers about their concerns on security and privacy issues. The goal of Cloud Computing is to share resources among the cloud service consumers, cloud partners, and cloud vendors i n the cloud value chain. The resource sharing at various levels results in various cloud offerings such as infrastructure clou d (e.g., hardware, IT infrastructure management), software cloud (e.g. SaaS focusing on middleware as a service, or traditio nal CRM as a service), application cloud (e.g., Application as a Service, UML modeling tools as a service, social network as a service), and business cloud (e.g., business process as a service). KeywordsCloud computing, SaaS, IaaS, PaaS, DaaS.