Unified Process or better know it like UP is an architecture-centric, use-case driven, iterative an incremental development process that leverages unified modeling language and is compliant with the system process engineering meta-model.
Unified process can be applied to different software systems with different levels of technical and managerial complexity across various domains and organizational cultures.
Unified process is based on the enlargement and refinement of a system through multiple iterations, with cyclic feedback and adaptation.
This system is developed incrementally over time, iteration by iteration, and thu this approach is also known as iterative and incremental software development. This system spread over four phases where each phace consist of one or more iterations.
Inception—the first and the shortest phase in the project. It is used to prepare basis for the project, including preparation of business case, establishing project scope and setting boundaries, outlining key requirements, and possible architecture solution together with design tradeoffs, identifying risks, and development of initial project plan—schedule with main milestones and cost estimates. If the inception phase lasts for too long, it is like an indicator stating that the project vision and goals are not clear to the stakeholders. With no clear goals and vision the project most likely is doomed to fail. At this scenario it is better to take a pause at the very beginning of the project to refine the vision and goals. Otherwise it could lead to unnecessary make-overs and schedule delays in further phases.
Elaboration—during this phase the project team is expected to capture a majority of system’s requirements (e.g., in the form of use cases), to perform identified risk analysis and make a plan of risk management to reduce or eliminate their impact on final schedule and product, to establish design and architecture (e.g., using basic class diagrams, package diagrams, and deployment diagrams), to create a plan (schedule, cost estimates, and achievable milestones) for the next (construction) phase.
Construction—the longest and largest phase within Unified Process. During this phase, the design of the system is finalized and refined and the system is built using the basis created during elaboration phase. The construction phase is divided into multiple iterations, for each iteration to result in an executable release of the system. The final iteration of construction phase releases fully completed system which is to be deployed during transition phase, and
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