Comprehensive Overview of the COCOMO Model Introduction to COCOMO The COCOMO (COnstructive COst MOdel) is a procedural software cost estimation model developed by Barry W. Boehm. It is used to estimate the cost, effort, and schedule when planning new software development. This model plays a crucial role in helping software developers, project managers, and stakeholders plan their projects effectively by forecasting various parameters that impact project outcomes. Basic Concepts of COCOMO Levels of COCOMO ● Basic COCOMO: Provides a rough estimate of software development costs based on size expressed in Lines of Code (LOC). ● Intermediate COCOMO: Refines these estimates by incorporating a set of cost drivers that affect project effort and duration. ● Complete COCOMO: Further refines estimates by considering the project as an assembly of multiple subsystems, each with potentially different characteristics. Categories of COCOMO ● Organic: Projects characterized by small teams with good experience working on relatively less complex applications. ● Semidetached: Intermediate projects with mixed teams having varying experience levels. ● Embedded: Complex projects requiring a set of tight hardware, software, and operational constraints. Intermediate COCOMO Model Key Characteristics ● The intermediate model includes 15 cost drivers that reflect various project attributes affecting effort and time. ● Cost drivers are classified into four categories: ● Product Attributes: Refers to the inherent complexity and reliability requirements of the product. ● Computer Attributes: Includes necessary execution speed and storage space. ● Personnel Attributes: Incorporates the experience level and capabilities of the development team. ● Development Environment Attributes: Captures the sophistication of the automation tools and other supports available for development. Application ● Project attributes are rated on a scale from one to three. ● Ratings guide the selection of cost multiplier values which adjust the initial estimates from the basic model. Complete COCOMO Model Essential Elements ● The complete model transcends the limitations of considering a project as a single homogeneous entity by addressing differing characteristics of various subsystems. ● Each subsystem’s cost is estimated separately, accounting for variance in attributes such as complexity, reliability, and team experience. ● This approach enables a more granular and accurate estimation which aggregates the subsystems’ costs for a comprehensive project cost forecast. Example Application ● A distributed Management Information System (MIS) with sub-components like: ● Database: Considered semi-detached. ● GUI: Viewed as organic software. ● Communication: Shaped as embedded software. ● The individualized cost assessment of each subsystem improves the accuracy of the total project estimate. Conclusion The COCOMO model, with its progressive improvements from basic to complete levels, provides a structured approach for software project cost estimation. By considering a range of influencing factors and breaking down projects into more manageable parts, COCOMO delivers more reliable and actionable insights for planning and managing software development efforts. For detailed insights into each aspect of the COCOMO model, including the specifics of the various cost drivers and their impacts, refer to the lecture notes from the Department of Computer Science and Engineering and Information Technology at VSSUT, Burla.