Rachana Desale, Purva Kolhatkar, Anju More, Piyush Katira, Vishal Kokane Prof.S.M.Jaybhaye / International Journal of Engineering Research and Applications (IJERA) ISSN: 2248-9622 www.ijera.com Vol. 3, Issue 3, May-Jun 2013, pp.042-046 42 | P a g e Software as a Service (SaaS) for Management information system using multiple tenants Rachana Desale, Purva Kolhatkar, Anju More, Piyush Katira, Vishal Kokane Prof.S.M.Jaybhaye (Department of Information Technology, Sinhgad College of Engineering, Pune University,Pune) ABSTRACT Today, reliable broadband internet access, service-oriented architectures (SOAs), and the cost inefficiencies of managing dedicated on-premises applications are driving a transition toward the delivery of decomposable, managed, shared, Web-based services called software as a service (SaaS). Tenants using a multitenant service operate in virtual isolation from one another; Organizations can use and customize an application as though they each have a separate instance, yet their data and customizations remain secure and insulated from the activity of all other tenants. The single application instance effectively morphs at runtime for any particular tenant at any given time. Multitenancy is an architectural approach that pays dividends to both application providers and users. Operating just one application instance for multiple organizations yields tremendous economy of scale for the provider. Only one set of hardware resources is necessary to meet the needs of all users, a relatively small, experienced administrative staff can efficiently manage only one stack of software and hardware, and developers can build and support a single code base on just one platform (operating system, database, etc.) rather than many. The economics afforded by multitenancy allow the application provider in turn offer the service at a lower cost to customers. Keywords-Cloud Computing, Multitenancy, SaaS, Virtualized database. I. Introduction Leave management system is an MIS that is required in every company, however big or small the company might be. Hence using the concepts of SaaS for multiple tenants we are going to build a real time flexible leave management system which will morph according to any company requirements and keep individual customizations and data of each company intact. II. Cloud Computing Cloud Computing is Internet based (Cloud) development with the use of computer technology (Computing). Cloud Computing is an emerging technology in the area of parallel and distributed computing. Clouds consist of a collection of virtualized resources, which include both computational and storage facilities that can be provisioned on demand, depending on the user’s needs. Cloud computing is defined as a computing capability that provides an abstraction between the computing resource and its underlying technical architecture (e.g. servers, storage, networks), enabling convenient, on demand network access. There are 3 types of cloud computing: 1) SaaS-Software as a Service Applications run on hosted servers as a service. 2) PaaS-Platform as a Service 3) IaaS-Infrastructure as a Service III. SaaS SaaS (Software as a Service) is an application hosted on a remote server and accessed through internet. Software as a Service (SaaS) is a model in which application is hosted as a service to customers who access it via the Internet Software as a service, sometimes referred to as ”on -demand software”, is a software delivery model in which software and associated data are centrally hosted on the cloud. Software as a service (or SaaS) is a way of delivering applications over the Internet as a service. Instead of installing and maintaining software, you simply access it via the Internet, freeing yourself from complex software and hardware management. The most important difference between SaaS applications and ordinary apps is multi-tenancy.  A multitenant web application framework for SaaS (IEEE Paper)[8]: In the framework, multiple tenants share a single application server, and this lowers operational costs. Industry-specific, tenant specific and department-specific customizations are supported by multilevel inheritance. It promotes reuse of user interface and business logic components. The system can scale by adding SaaS application servers. This also improves the availability of the system.