Systems Analysis and Design

The analysis and design of systems contribute to two main parts of the SDLC. The SLDC has four main stages: contriving, analysis, excogitation, and enforcement. The stage of planning allows the understanding of the building of the information to be built. This assists in the determination of the building methods for the project team. The stage of analysis answers the why, where and when questions of the project which specifies the need, the place and the time plan for the project. The stage usually has a tri-step shape which is followed to realize what is needed perfectly, (Dennis, et.al 18). A strategy of analysis is formulated to check on the feasibility of the present system and hence the shortcomings that it might be having. The necessities assembled in the business model is the next analytical step. This checks whether the team will be able to meet all the necessities of the new system being developed Coming up with the system proposal to be presented to the project manager to decide whether the project is viable or not. System proposal forms the deliverable of the analysis phase and is used in the next phase.
The design phase checks on the definition of the faculties, ports, architecture, elements, and information for any system to be able to meet the specifications of the software requirements. A system specification from this phase informs the next phase (implementation) with a collection of deliverables. The Unified Model Language is a model that is used to design object oriented software/systems used in System Analysis and Design Phases.

The Use case Diagrams capture functional requirements with each use case representing a high-level business goal, (Shelly, et.al 39). Use cases are employed to join actors in the diagrams so as to constitute many different characters which interact with the functions. The Class Diagrams forms the blueprint of the classes required to implement a system. The Sequence Diagrams indicates any relationships between the components of the system which include its division and the end user through the passing of message. We have communication diagrams which are employed in showing the coaction among the lifelines and their connection in the representation of the importance of communication when executing and interacting with the elements of the system.
The Activity Diagram is a diagram that models the flow of control. This diagram divides the actions depending with any participant type involved. The SMD indicates the changes in the state and the crucial state objects accurately. The Components Diagram models the structures that build up the entire software system. Small parts gear-up forming bigger parts. Deployment Diagrams is whereby Software as artifacts and hardware as nodes are modeled to depict how the system will be deployed. All the above diagrams are either Environmental models or Behavioral models. The Environmental Models defines the interface existing between the scheme and the surrounding, (Dennis, et.al 48). The Environmental Model distinguishes the information produced by the system produces as the output being released to the surrounding and the data being as an input into the system from the surrounding. The components in this model include statement of purpose, event lists and context diagrams. The Behavioral Models are logical models defining what is a system in or what it does independent of implementations. Process Modeling involves Data Flow Diagrams and Data Modelling, (Shelly, et.al 79). The Data Flow Diagram is a tool that shows the flow of data through a system and the amount of work or processing performed by that system. A data model describes how data flows through the business processes in an organization. An ERD is a depiction of the data using the description of the data through its relationships as well as its entities. Entities hold similar kinds of information and lines joining entities depicts relationship among the data.
Work cited
Dennis, Alan, and Barbara Haley Wixom. Systems Analysis and Design. New York: Wiley, 2010.
Shelly, Gary B, Thomas J. Cashman, and Harry J. Rosenblatt. Systems Analysis and Design. Boston: Course Technology, 2011. Print.