What is RUP?

RUP short for Rational Unified Process is a process for software engineering. Originally develped by Rational Software, Inc. - now acquired by IBM.

RUP focuses on the following best practices:

1. Four major phases in a software development cycle (inception, elaboration, construction and transition)

2. Within each phase RUP allows for iteration and incremental development. this supports refined requirements, risk reduction and results oriented management.

3. Disciplines which group activities by nature. There are nine disciplines defined (business modeling, requirements, analysis and design, implementation, test, deployment, configuration management, project management and environment). These disciplines spread across the four phases of a software project.

4. Manage requirements using tools that support traceability, prioritization, validation and quality management.

5. Develop component-based architectures, where components are primary concepts for design. They are self-contained modules with clear interfaces that can provide a well-defined function.

6. Visually model software using languages such as UML, or SysML. Numerous tools on the market support these languages such as IBM's Rational Suite, IBM's Telelogic DOORS, iRise, Visual Use Case, Visual Paradigm and many others.

7. Verify software quality, especially in the areas of functional, performance and reliability compliance.

8. Control changes to software through a traceable and end-to-end approach.

Common Software System Development Methodologies

There are 4 common software system development methodologies. These methodologies comprise of:

(1) A process - to define activities or tasks to achieve the goal of the methodology
(2) A vocabulary - to describe the process and work products created during the process application.
(3) Rules and guidelines - to define the quality of the process and the work products

The four methodologies are shown in the table below along with their strengths and weaknesses.

Domain	RUP	Shlaer-Mellar	CRC	XP
Emphasis	- Incremental and iteration	- Execution for verification	Scenarios and simplicity	Simplicity, design through integration and refactoring
Strengths	- Comprehensive - Well Defined artifacts and roles - Incremental deliveries	- Simulation capability - Well defined testing rules - Well defined transition from one step in the process to another - Real-time system support	- Simplicity - Easy to use to transition from procedural to object oriented concepts - Focuses on object value, leading to optimized system	- Focuses and cares about the programming environment - Supports and requires close relationship between clients and developers - Accounts for changes in the development process
Weakness	- Large and difficult - Complicated rules - Customization is not straight-forward - Limited vendors supporting the process	- Considerable learning curve - Focuses too much on state modeling. - Limited vendors supporting the process	- Supports primarily classes - Requires a facilitator	- Relies on an ideal development environment - Depends extensively on client commitments - Requires high quality human interaction among development team - The system is in a constant state of maintenance