I nternational Journal of Application or I nnovation in E ngineering & M anagement (I JAI E M ) Web Site: www.ijaiem.org Email: editor@ijaiem.org, editorijaiem@gmail.com Volume 1, Issue 2, October 2012 ISSN 2319 - 4847 Volume 1, Issue 2, October 2012 Page 226 ABSTRACT Cloud computing is an attractive computing model since it allows for resources to be provisioned according to a demand basis. It has also made it possible to process a large amount of data, using clusters of commodity computers. Moreover, the diffusion of cloud computing is expected to generate substantial direct and indirect impacts on economic and employment growth and also to face the world with new possibilities which are specific to cloud computing. In this paper we have introduced the most renowned cloud solution providers at present, and explained their features and different aspects. Besides, we have given a telling overview of cloud computing concept, service models and deployment methods. Keywords: Cloud Solution Providers, Deployment Methods, Cloud Service Models, Cloud Concept 1. INTRODUCTION Cloud computing is a pay-per-use consumption and delivery model that enables real-time delivery of configurable computing resources (for example, networks, servers, storage, applications, services) [2]. Typically, these are highly scalable resources delivered over the Internet to multiple companies, which pay only for what they use. Cloud delivery models can help organizations scale their investments as they grow their business. They can also open the door to new business approaches through standardized applications, infrastructure, testing environments and business processes that help improve service delivery and efficiency [1]. This concept that is broadly recognized by Australian businesses and government agencies. But not always well understood in details. To some degree, this is due to the rapid evolution of cloud computing service offering. Indeed, cloud computing is a catchall term that is often misused. The US National Institute of standards and Technology (NIST) defines cloud computing as:”A model for enabling ubiquitous, convenient, on demand network access to a shared pool of configurable computing resources that can be rapidly provisioned and released.” In practice, cloud computing describes three over-aching and related service models, delivered over a network to replace product models. Each of these service lines displays the same core criteria. The concept itself has been around since the 1960s and has been boosted in recent years. Various factors have contributed to this such as the increased availability of broadband internet, improved technologies such as virtualization and new models to deliver web-based services. The concept itself has been around since the 1960s and has been boosted in recent years. Various factors have contributed to this such as the increased availability of broadband internet, improved technologies such as virtualization and new models to deliver web-based services. Cloud computing has the following main characteristics[4]: • Multi-tenancy – IT resources are shared between different users and customers • Rented service delivery model – customers pay for the service instead of buying software licenses and hardware • On-demand usage/flexibility – cloud services can be used almost instantly and can easily be scaled up and down • External data storage – a customers’ data is usually stored externally at the location of the cloud computing vendor Parts of IT resources can also be reserved and dedicated for one customer only. This type of cloud computing is called private cloud computing Cloud services can also be hosted, delivered and used exclusively within one organization. This is called internal cloud computing. As this variant is almost fully dependent on internal, on-premise IT resources, it is highly questionable if internal cloud computing should be defined as cloud computing at all. In this paper, we have first explained about the concept of cloud computing and its various categories. We have mentioned Cloud service models and Deployment methods at present in chapter 2. After that, in chapter three, we have focused on current reputed solution providers in the scope of cloud computing. Finally, chapter 4 concludes the paper. 2. CLOUD SERVICE MODELS AND DEPLOYMENT METHODS A Survey on Cloud Computing and Current Solution Providers Vahid Ashktorab 1 , Seyed Reza Taghizadeh 2 , Dr. Kamran Zamanifar 3 1 Department of Computer Engineering, Islamic Azad University of NajafAbaad, Isfahan, Iran 2 Department of Information Technology, Kahje-Nassir-Toosi University of Technology, Tehran, Iran 3 Department of Computer Engineering, Islamic Azad University of NajafAbaad, Isfahan, Iran