During analysis, we constructed a conceptual model and a behavioral model for the proposed system. In the design step, we use the class structure defined in the conceptual model to design a system that behaves in the manner specified by the behavioral model. The main UML tool that we employ here is the sequence diagramSequence diagram. In a sequence diagram, the designer details how the behavior specified in the model will be realized. This process requires the system’s actions to be broken down into specific tasks, and the responsibility for these tasks to be assigned to the various players (classes and objects) in the system. In the course of assigning these responsibilities, we determine the public methods of each class and also describe the function performed by each method. Since the stage after design is implementation, which is coding, testing, and debugging, it is imperative that we have a full understanding of how the required functionality will be realized through code.