International journal of Science Technology & Management (IJSTM) ISSN: 2229-6646 Presented in National Conference on RTICCN-2015 at CGC-COE , Landran , Mohali(Punjab) on 26-27 th March 2015 Cloud Computing- A new Trend in IT Era Gurleen Kaur #1 , Ranjit Kaur *2 , Sita Rani #3 #1 Assistant Professor, Department of Computer Applications, Ludhiana Group of Colleges, Ludhiana, Punjab, India 1 gurleenkkohli89@gmail.com *2 Assistant Professor, Department of Computer Applications, Ludhiana Group of Colleges, Ludhiana, Punjab, India 2 ranjit75135@gmail.com #3 Associate Professor cum HOD [Department of Computer Science Engineering], Ludhiana Group of Colleges, Ludhiana, Punjab, India 3 sitasaini80@yahoo.in Abstract— Cloud computing is one of the most recent trends in IT sector. It involves sharing of computer resources in turn saving huge cost. It facilitates the users with flexible data and is becoming a business standard now a days. This paper is a brief review of various characteristics of cloud computing. Different cloud services and deployment models along with the steps to set up own private cloud is discussed in this paper. A comparison of various cloud services is also made and major service providers of cloud computing are discussed. An effort is made to throw some light on Big Data, an important aspect of cloud computing. In the end various challenges in the field of loud computing are discussed. It is also concluded that when user data is kept on third party infrastructure, it could be misused, so security is one of the biggest issue in cloud computing need to be dealt with. Keywords— Cloud computing, Infrastructure as a Service, Platform as a Service, Software as a Service, Private Cloud, Public Cloud, Big Data I. INTRODUCTION Cloud is a storage space which allows data transmission over the network. The data emerged from the cloud is encapsulated, converted and transported in various ways. Cloud computing in an emerging area of distributed computing which facilitates organizations by making information technology services available as a commodity[1]. Cloud computing means different to different people. Few consider it as outsourcing IT services and some define as a framework providing software, storage, computing power and services to various entities. Cloud computing is an internet- based network made up of large number of servers taking into consideration open standards, modularity and cost[1],[24]and[25]. Demand for cloud based software is rising because the approach allows the organization to start using new programs faster and at lower cost than already existing products that are installed at a customer’s own data center[17]. Cloud as a host delivers services over the internet. In cloud computing, the clients have to pay as per their usage. This facilty of pay for what you use is just like you pay your electricity bills and for fuel at petroleum station[17]and[18]. A. CHARACTERISTICS OF CLOUD COMPUTING Following are the important characteristics of cloud computing [17]and[19]:  On Demand Service: A user can use resources/services as per their need. There is no need to interact with cloud service provider personnel.  Location Independence: Cloud computing allows the access of resources from any part of the world, you need to have internet access from your device.  Broad Network Access: Using standard methods, a user can access resources/services generally available over broadband facilitating platform independency.  Rapid Elasticity: The number of resources can be dynamically increased or decreased.  Resource Pooling: Resources created by the cloud service provider are shared amongst users via existing central large pool.  Measured Service: Client has to pay as per their usage of the resources/services.  Scalability: Ensures the well functioning of the system on scale-ups or scale-outs.  Reliability: Ensures reliability in terms of computation and resource accessibility. II. CLOUD SERVICES Cloud systems provide various services , as shown in Fig. 1, which have become popular because they are economical and provide large space for storage. An internet connection is required to use different cloud services[7]and[8].