A new path based reliability approach for estimation of reliability of Component Based Software Development Lata Nautiyal*, Dr. Neena Gupta**, Dr. Sushil Chandra Dimri*** *Department of Computer Applications Graphic Era University Dehradun, India lata.nautiyal1903@gmail.com **Department of Computer Sciences Kanya Gurukul Campus, GKV Dehradun, India neena71@hotmail.com *Department of Computer Applications Graphic Era University Dehradun, India dimri.sushil82@gmail.com Abstract—One of the motivations for stipulating software architectures explicitly is the use of high intensity structural design information for improved control and prediction of software system quality attributes. Gradually software applications are mounting more complex and with more stress on reuse. The focus of this paper is to provide an outline for the state of the art of Component Based Systems reliability estimation and to present an approach for determining the reliability of component-based software architectures. The proposed model in this paper provides software system dependability in term of the reliability of different execution paths and the usage ratio of each component. The reliability of a component most powerfully depends on its environment. Therefore, we promote a reliability model parameterized by mandatory component reliability in a deployment perspective. Keywords-Software reliability, Probability distribution, weighted mean, Component reliability, component- based software development. I. INTRODUCTION Software reliability is one of the key metrics for determining the eminence of software. It is often defined as the probability of a failure-free operation of a computer program within a specified exposure time interval. Most of the analytical models, developed for measuring reliability, focus on observing the behavior of software, based on an operational profile and not on software architecture. Software architecture is defined as the structure of software at an abstract level, consists of a set of components, connectors and configurations. Modern software often embodies complex heterogeneous construction to achieve multiple quality requirements, such as the use of a parallel architecture to increase performance and/or introduce a back-up component to provide fault tolerance. In the new era of science where software are required almost all aspects of life, we can’t imagine life without software. We have gigantic complex systems, massive data handling, record keeping everywhere software is required, Now the question comes how we can develop reliable software in less amount of time ?,the answer is the Component based software engineering . But the reliability of the software is a big question, the Software system failure occurs daily but in some cases the failures are not costly but some time the cost cannot be compensated, this makes reliability of the system very important. II. COMPONENT RELIABILITY AND ITS CONTRIBUTION TO SYSTEM RELIABILTY The reliability of a component can be uttered as a function from an input allotment or operational outline to a number between 0 and 1, as mentioned in [1]. In this paper, we presume that individual component reliability is known in advance. One of the methods to estimate component reliability is by identifying operational and logical errors and then predicting component reliability based on them [2]. This approach is useful when no documentation and source code is available, and can be used effectively when components are basically program functions. Another loom is based on service architecture of a component, measuring component reliability on the basis of the services used by that component where involvement of each reliability service is weighted by relative frequency of invocation of that service [3]. Overall system reliability is a function of Lata Nautiyal et al. / International Journal of Computer Science Engineering (IJCSE) ISSN : 2319-7323 Vol. 2 No.06 Nov 2013 295