The Rational Unified Process (RUP) is an iterative software development process framework created by the Rational Software Corporation, a division of IBM since 2003. RUP is not a single concrete prescriptive process, but rather an adaptable process framework, intended to be tailored by the development organizations and software project teams that will select the elements of the process that are appropriate for their needs. RUP is a specific implementation of the Unified Process.
Rational Software originally developed the rational unified process as a software process product. The product includes a hyperlinked knowledge-base with sample artifacts and detailed descriptions for many different types of activities. RUP is included in the IBM Rational Method Composer (RMC) product which allows customization of the process.
Philippe Kruchten, an experienced Rational technical representative was tasked with heading up the original RUP team. This journey began with the creation of the Rational Objectory Process (ROP) in 1996, when Rational acquired the Objectory Process that had been written by Ivar Jacobson and company. This was renamed Rational Unified Process (RUP) in subsequent releases, in part to align the name with that of the Unified Modeling Language.
These initial versions combined the Rational Software organisation's extensive field experience building object-oriented systems (referred to by Rational field staff as the Rational Approach) with Objectory's guidance on practices such as use cases, and incorporated extensive content from Jim Rumbaugh's Object Modeling Technology (OMT) approach to modeling, Grady Booch's Booch method, and the newly released UML 0.8.
To help make this growing knowledge base more accessible, Philippe Kruchten was tasked with the assembly of an explicit process framework for modern software engineering. This effort employed the HTML-based process delivery mechanism developed by Objectory. The resulting "Rational Unified Process" (RUP) completed a strategic tripod for Rational:
This guidance was augmented in subsequent versions with knowledge based on the experience of companies that Rational had acquired.
In 1997, a requirements and test discipline were added to the approach, much of the additional material sourced from the Requirements College method developed by Dean Leffingwell et al. at Requisite, Inc., and the SQA Process method developed at SQA Inc., both companies having been acquired by Rational Software.
In 1998 Rational Software added two new disciplines:
These additions lead to an overarching set of principles that were defined by Rational and articulated within RUP as the six best practices for modern software engineering:
These best practices were tightly aligned with Rational's product line, and both drove the ongoing development of Rational's products, as well as being used by Rational's field teams to help customers improve the quality and predictability of their software development efforts.
Additional techniques including performance testing, UI Design, data engineering were included, and an update to reflect changes in UML 1.1.
In 1999, a project management discipline was introduced, as well as techniques to support real-time software development and updates to reflect UML 1.3. Besides, the first book to describe the process, The Unified Software Development Process (ISBN 0-201-57169-2), was published in the same year.
Between 2000 and 2003, a number of changes introduced guidance from ongoing Rational field experience with iterative development, in addition to tool support for enacting RUP instances and for customization of the RUP framework. These changes included:
IBM acquired Rational Software in February 2003.
RUP is based on a set of building blocks and content elements, describing what is to be produced, the necessary skills required and the step-by-step explanation describing how specific development goals are to be achieved. The main building blocks, or content elements, are the following:
Within each iteration, the tasks are categorized into nine disciplines:
The RUP has determined a project life-cycle consisting of four phases. These phases allow the process to be presented at a high level in a similar way to how a 'waterfall'-styled project might be presented, although in essence the key to the process lies in the iterations of development that lie within all of the phases. Also, each phase has one key objective and milestone at the end that denotes the objective being accomplished. The visualization of RUP phases and disciplines over time is referred to as the RUP hump chart.
The primary objective is to scope the system adequately as a basis for validating initial costing and budgets. In this phase the business case which includes business context, success factors (expected revenue, market recognition, etc.), and financial forecast is established. To complement the business case, a basic use case model, project plan, initial risk assessment and project description (the core project requirements, constraints and key features) are generated. After these are completed, the project is checked against the following criteria:
If the project does not pass this milestone, called the life cycle objective milestone, it either can be cancelled or repeated after being redesigned to better meet the criteria.
The primary objective is to mitigate the key risk items identified by analysis up to the end of this phase. The elaboration phase is where the project starts to take shape. In this phase the problem domain analysis is made and the architecture of the project gets its basic form.
The outcome of the elaboration phase is:
This phase must pass the lifecycle architecture milestone criteria answering the following questions:
If the project cannot pass this milestone, there is still time for it to be canceled or redesigned. However, after leaving this phase, the project transitions into a high-risk operation where changes are much more difficult and detrimental when made.
The key domain analysis for the elaboration is the system architecture.
The primary objective is to build the software system. In this phase, the main focus is on the development of components and other features of the system. This is the phase when the bulk of the coding takes place. In larger projects, several construction iterations may be developed in an effort to divide the use cases into manageable segments to produce demonstrable prototypes.
The primary objective is to 'transit' the system from development into production, making it available to and understood by the end user. The activities of this phase include training the end users and maintainers and beta testing the system to validate it against the end users' expectations. The system also goes through an evaluation phase, any developer which is not producing the required work is replaced or removed. The product is also checked against the quality level set in the Inception phase.
If all objectives are met, the product release milestone is reached and the development cycle is finished.
The IBM Rational Method Composer product is a tool for authoring, configuring, viewing, and publishing processes. See IBM Rational Method Composer and an open source version Eclipse Process Framework (EPF) project for more details.
In January 2007 the new RUP certification examination for IBM Certified Solution Designer - Rational Unified Process 7.0 was released which replaces the previous version of the course called IBM Rational Certified Specialist - Rational Unified Process. The new examination will not only test knowledge related to the RUP content but also to the process structure elements.
To pass the new RUP certification examination, a person must take IBM's Test 839: Rational Unified Process v7.0. You are given 75 minutes to take the 52 question exam. The passing score is 62%.