Deliverable Structure Chart that maps the project life cycle and systems development life cycle phases to the deliverables defined in the DDT.
Although the electronic commerce application system is listed as a project-oriented deliverable, we really do not have any idea what exactly will be delivered to the client. In general, the application system will be the largest project deliverable and will, therefore, require the most time and resources to complete. Identifying the features and functionality of the application system (and their complexity) will be pivotal for estimating the time and cost of producing this deliverable.
Product-Oriented Scope Definition Tools Product scope therefore focuses on identifying the features and functionality of the information system to be implemented.
Commerce banking project
A useful tool for refining the scope boundary and defining what the system must do is a modeling tool called a context level data flow diagram (DFD). A DFD is a process model that has been available for quite some time and is often taught in systems analysis and design courses. A context level DFD, however, presents a high-level representation of the system that has one process (i.e., a circle or rounded rectangle that represents the system as a whole) and depicts all the inflows and outflows of data and information between the system and its external entities. The external entities are usually represented by a square and can be people, departments, or other systems that provide or receive flows of data. Arrows represent the directional flow of data between external entities and the system. Each arrow and entity should be labeled appropriately. Lower level DFDs can be developed later to model the processes and flows of data in greater detail. An example of a context level DFD for our banking electronic commerce system is provided in Figure 5.4. As you can see, the high level features and functionality of the system focus on what the system must do.
Another useful tool for defining the product scope is the use case diagram, which has been used in the object-oriented world as part of the Unified Modeling Language (UML). While Jacobson (Jacobson, Cristerson et al. 1992) introduced the use case as a tool for software development, a use case diagram can provide a high level model for defining, verifying, and reaching agreement upon the product scope.
The use case diagram is a relatively simple diagram in terms of symbols and syntax, but it is a powerful tool for identifying the main functions or features of the system and the different users or external systems that interact with the system. At this early stage of the project, the use case can provide a high level diagram that can be further refined and detailed during requirements analysis later in the project.
Actors are people (i.e., users, customers, managers, etc.) or external systems (i.e., the bank's ERP system) that interact, or use, the system. Think of actors in terms of roles (e.g., customer) instead of as specific individuals (e.g., Tom Smith). A use case,
Accouru batanee info
Accouru batanee info
on the other hand, depicts the major functions the system must perform for an actor or actors. When developing a use case diagram, actors are identified using stick figures, while use cases are defined and represented using ovals. Figure 5.5 provides an example of a use case diagram for the bank example.
As you can see in Figure 5.5, the use case diagram provides a simple yet effective overview of the functions and interactions between the use cases and the actors. The box separating the use cases from the actors also provides a system boundary that defines the scope boundary. Use cases inside the boundary are considered within the scope of the project, while anything outside of the boundary is considered outside the scope of the project. Listing the actors provides an opportunity to identify various stakeholders and can be useful for understanding the needs of the organization as a whole. It can be useful not only for addressing competing needs among various stakeholders, but also for identifying security issues as well (Fowler and Scott 1997). The development of a use case diagram is an iterative process that can be developed during a joint application development (JAD) session. JAD is a group-based method where the users and systems analysts jointly define the system requirements or design the system (Turban, Rainer and Potter 2001).
The use case diagram used to define the product scope can be used to refine the level of detail and functionality later on in our project. Following our example, the use case diagram in Figure 5.5 identifies the customer actor as using the system to transfer payments. However, a scenario or set of scenarios could be developed during the analysis and design phases of our project to determine how a customer would transfer funds successfully, while another scenario might focus on what happens when a customer has insufficient funds in their account. This level of detail is more suited to the requirements definition rather than the scope definition. At this point, it is more important to identify that the system must allow a customer to transfer funds than to identify how the funds may be transferred. Later on, the product scope can be compared or measured against the detailed requirements. These detailed requirements will be defined during the SDLC component of the ITPM.
But what is the appropriate level of detail for defining the product scope? Knowing the right level of detail is more an art than a science. The right level allows the project manager to estimate the time it will take to produce the application system accurately. As the next chapter shows, estimating the time and effort to produce the application system deliverable depends on the size of the application, the number of features incorporated, and their level of complexity. Therefore, the quality of the estimates will be greatly influenced by our understanding of the information system to be delivered.
The time and resources committed to developing the project charter and plan may limit the amount of time and energy we can devote to defining the details of the information system. Thus, the objective during this planning stage of the project should be to secure enough detail about the information system to allow us to estimate the time and effort needed to produce this deliverable. During the analysis and design phases, we can commit more time and resources to increasing our understanding and to documenting the level of detail needed to built and deliver the system.
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What you need to know about… Project Management Made Easy! Project management consists of more than just a large building project and can encompass small projects as well. No matter what the size of your project, you need to have some sort of project management. How you manage your project has everything to do with its outcome.