The work described in this paper is an investigation of COTS-based software development within a particular NASA environment, with an emphasis on the processes used. Fifteen projects using a COTS-based approach were studied and their actual process was documented. This process is evaluated to identify essential differences in comparison to traditional software development. The main differences, and the activities for which projects require more guidance, are requirements definition and COTS selection, high level design, integration and testing. Starting from these empirical observations, a new process and guidelines for COTS-based development are developed and briefly presented. The new process is currently under experimentation.

Abstract. Software products are an everyday phenomenon. Yet, there are very few scientific studies reported on the engineering of software as a product in particular. This paper stipulates the urgent need for more research on product software. The various terms used for software products are reviewed and some categorizations of software products are presented. Moreover, we provide a software product development framework to position the key business domains in a product software company. 1

COTS based development impacts several issues in software development. New techniques have been proposed, or existing ones have been adapted. Several approaches have been proposed for effort and size estimation, product selection, and architectural mismatches identification. But a fundamental question must be clarified before: what is a COTS product? According to the literature a COTS seems to be anything from an operating system to a UI widget. It appears obvious that a finer level of granularity is required if we want to acquire a deeper insight in COTS related issues. This paper proposes a COTS classification scheme, which is as inclusive as possible.

The work described in this paper is an investigation of COTS-based software development within a particular NASA environment, with an emphasis on the processes used. Fifteen projects using a COTS-based approach were studied and their actual process was documented. This process is evaluated to identify essential differences in comparison to traditional software development. The main differences, and the activities for which projects require more guidance, are requirements definition and COTS selection, high level design, integration and testing. Starting from these empirical observations, a new process and set of guidelines for COTS-based development are developed and briefly presented. Keywords Commercial off-the-shelf, COTS, component-based, empirical study, software development process. 1

Commercial Off The Shelf tools (COTS) are now widely distributed, of good quality, relatively cheap and cover most of the application domains. It is thus a surprise to consider that it is uncommon to reuse COTS when building large applications. At least it is recognized that building a large application based on COTS is a tough issue.

Many software engineering research tools are stand-alone applications that have trouble interoperating with other development tools and do not fit well into the software developers' established work processes. Our main hypothesis is that in order for new tools to be adopted effectively, they must be compatible with both existing users and existing tools.

In the last decade, the world of software development has evolved rapidly. This evolution has led to Component-Based Software Development (CBSD), which in turn has generated tremendous interest in the development of plug-and-play reusable software, leading to the concept of Commercial Off The Shelf (COTS) software components. The use of COTS is increasingly becoming commonplace. This is mainly due to shrinking budgets, accelerating rates of COTS enhancement, reducing development time and effort constraints, and expanding system requirements. However, the COTS marketplace is characterized by a vast array of products and product claims, extreme quality and capability differences between products, and many products incompatibilities, even when they purport to adhere to the same standards. Therefore, there is need for a robust COTS evaluation methodology to help software developers select appropriate components for projects. A variety of COTS evaluation methods have already been proposed. These methods are based on either consensual opinion aggregation approach or regression models. However, both approaches are inadequate for the COTS Evaluation process. In this paper, we propose an agent-based COTS evaluation method, which models each of the players as either a cooperative or a competing agent that is capable of making its own decisions to meets its goals. In this model, there is an administrator agent that collects, evaluates, and combines knowledge from different areas of expertise (Roles) to offer support in the COTS selection process. This way, we circumvent COTS evaluation problems associated with the consensual opinion aggregation and the regression models approaches. 1.

This paper has illustrated how a system dynamics model and simulation of the COTS integration and glue code development can be used to assist in predicting when good software productivity levels will be achieved. Our model can be calibrated to a project

This paper summarizes the results of a study on fifteen projects that used a COTS-based approach. The process they followed is evaluated to identify essential differences in comparison to traditional software development. The main differences, and the activities for which projects require more guidance, are requirements definition and COTS selection, high level design, integration and testing.

References ................................................................................................................... 6 This is a partial and biased list of literature resources on COTS. It is incomplete because (save a few exceptions) I ve read or at least browsed all the literature listed here. It is biased because it somewhat reflect my personal discovery path in this broad field. 1 Definitions and classifications 1.1 COTS Definitions Source Description Federal Acquisition Regulations [1] The acronym "COTS" stands for Commercial-Off-The-Shelf, so firstly we must define what is 'commercial', and what is 'off-the-shelf'. The official definition of the term "commercial" is given in the Federal Acquisition Regulations (FARs). A commercial item is: 1. Property customarily used for non governmental purposes and has been sold, leased, or licensed (or offered for sale, lease or license) to the general public; 2. Any item evolved from an