The waterfall model is a sequential design process, often used in software development processes, in which progress is seen as flowing steadily downwards (like a waterfall) through the phases of Conception, Initiation, Analysis, Design, Construction, Testing, Production/Implementation and Maintenance.

The waterfall development model originates in the manufacturing and construction industries: highly structured physical environments in which after-the-fact changes are prohibitively costly, if not impossible. Since no formal software development methodologies existed at the time, this hardware-oriented model was simply adapted for software development.^{[citation needed]}

The first known presentation describing use of similar phases in software engineering was held by Herbert D. Benington at Symposium on advanced programming methods for digital computers on 29 June 1956. This presentation was about the development of software for SAGE. In 1983 the paper was republishedwith a foreword by Benington pointing out that the process was not in fact performed in strict top-down, but depended on a prototype.

The first formal description of the waterfall model is often cited as a 1970 article by Winston W. Royce, though Royce did not use the term “waterfall” in this article. Royce presented this model as an example of a flawed, non-working model (Royce 1970). This, in fact, is how the term is generally used in writing about software development—to describe a critical view of a commonly used software practice.

Rational Unified Process is what is commonly known as RUP. It was developed by the IBM Corporation. A part of the IBM Corporation is the Rational Software Corporation which developed the RUP.

RUP is an adaptable and iterative software process framework. It is not prescriptive or singular process.

Rational Unified Process Origin

The Rational Unified Process framework was originally developed and created by its namesake, Rational Software. IBM then took over Rational Software in 2003.

What is Rational Unified Process (RUP)?

Rational Unified Process is an iterative adaptive software process.  RUP framework is built on blocks or content elements. The main blocks answer the questions of who, what and how. The “Who” part is encompassed in the block “Roles “which define certain related responsibilities and competencies. The “What “part is encompassed in the building block “Work Products “that defines the result of a task. The “How” part is encompassed in the building block “Tasks “which is nothing but a unit of work that is assigned to a Role and which is intended to produce a result.

Iteration consists of nine disciplines. Out of these nine disciplines, six are engineering disciplines like Business Modeling, Requirements, Design and Analysis, Implementation, Test, Deployment and remaining there are supporting disciplines which consist of Configuration and Change Management, Environment and Project Management. These iterations have to be followed with guidelines and templates at each stage. This way RUP provides a set of standards to be adhered to for all the stages of the System Development Life Cycle (SDLC). The RUP consists of a life cycle with four distinct phases as listed below.

The RUP Life Cycle phases:

1) INCEPTION

2) ELABORATION

3) CONSTRUCTION

4) TRANSITION

1) INCEPTION: Inception is the phase where the concept is actually commenced or initiated. The concept is explored with the definition of the scope of business, the stakeholders, cost benefit analysis, feasibility analysis etc. Inception phase provides a strong foundation to the phases to come next. Hence Inception phase must be properly planned and done.

2) ELABORATION: Elaboration is the second phase after Inception. Here the first draft is finalized and the requirements are finalized so that the work can take place.

3) CONSTRUCTION: Construction is the third phase of the RUP Life Cycle. As can be thought, in the CONSTRUCTION phase, the actual work begins. The software is actually ‘constructed’ in this phase and most important of all – the coding part of the project; is done in this phase. Testing is also done in this phase itself.

4) TRANSITION: Transition is the final phase of the RUP Life Cycle. Any project, no matter how good it may have been conceptualized and developed, needs to be successfully complete the transition phase at the client’s end .Here, software is released to the client and support phase then effectively starts.

USE OF RUP:

By its adaptive nature, RUP is a framework that can be used by any corporation or software project team for its purpose, by choosing the elements they need from it.  It is this specific adaptive tailoring as per needs feature of RUP which makes it highly popular with the developers team and the industry.

Rational Unified Process is what is commonly known as RUP. It was developed by the IBM Corporation. A part of the IBM Corporation is the Rational Software Corporation which developed the RUP.

RUP is an adaptable and iterative software process framework. It is not prescriptive or singular process.

Rational Unified Process Origin

The Rational Unified Process framework was originally developed and created by its namesake, Rational Software. IBM then took over Rational Software in 2003.

What is Rational Unified Process (RUP)?

Rational Unified Process is an iterative adaptive software process.  RUP framework is built on blocks or content elements. The main blocks answer the questions of who, what and how. The “Who” part is encompassed in the block “Roles “which define certain related responsibilities and competencies. The “What “part is encompassed in the building block “Work Products “that defines the result of a task. The “How” part is encompassed in the building block “Tasks “which is nothing but a unit of work that is assigned to a Role and which is intended to produce a result.

Iteration consists of nine disciplines. Out of these nine disciplines, six are engineering disciplines like Business Modeling, Requirements, Design and Analysis, Implementation, Test, Deployment and remaining there are supporting disciplines which consist of Configuration and Change Management, Environment and Project Management. These iterations have to be followed with guidelines and templates at each stage. This way RUP provides a set of standards to be adhered to for all the stages of the System Development Life Cycle (SDLC). The RUP consists of a life cycle with four distinct phases as listed below.

The RUP Life Cycle phases:

1) INCEPTION

2) ELABORATION

3) CONSTRUCTION

4) TRANSITION

1) INCEPTION: Inception is the phase where the concept is actually commenced or initiated. The concept is explored with the definition of the scope of business, the stakeholders, cost benefit analysis, feasibility analysis etc. Inception phase provides a strong foundation to the phases to come next. Hence Inception phase must be properly planned and done.

2) ELABORATION: Elaboration is the second phase after Inception. Here the first draft is finalized and the requirements are finalized so that the work can take place.

3) CONSTRUCTION: Construction is the third phase of the RUP Life Cycle. As can be thought, in the CONSTRUCTION phase, the actual work begins. The software is actually ‘constructed’ in this phase and most important of all – the coding part of the project; is done in this phase. Testing is also done in this phase itself.

4) TRANSITION: Transition is the final phase of the RUP Life Cycle. Any project, no matter how good it may have been conceptualized and developed, needs to be successfully complete the transition phase at the client’s end .Here, software is released to the client and support phase then effectively starts.

USE OF RUP:

By its adaptive nature, RUP is a framework that can be used by any corporation or software project team for its purpose, by choosing the elements they need from it.  It is this specific adaptive tailoring as per needs feature of RUP which makes it highly popular with the developers team and the industry.

What is SDLC (Software Development Life Cycle)?

SDLC or Software Development Life Cycle is the life cycle literally of the development of a system or software. This life cycle details all the processes that a system undergoes while it is being designed. That is the basic layman understanding of what SDLC stands for.

The steps of the System Development Life Cycle are detailed as below. They show the detailed working of how a system is developed for a particular project.

The Software Development Life Cycle (SDLC) starts when a client expresses the need to start a new project. Once the project is in hand, the steps of the SDLC work as:

• Project Planning:
  • Planning is the core of every process and only effective planning can make a Business Analyst realize if the intended system can really be developed or not. A feasibility study is conducted in this stage to determine if the actual system intended is indeed possible to work upon or not.
• System Analysis and Requirements Definition:
  • Here, the requirements of the client in the system to be developed are properly analyzed and then a final requirement definition is written by the Business Analyst in consultation with the client, who will be the end- user of the project. This requirements definition is used by the software team of programmers and developers to start the project.
• System Design:
  • This is the process of SDLC where the system is actually designed as per the requirements. The process of database design, structure design, nuances of the client/server technology, defining tiers of package architecture are all defined properly in this phase.
• System Development:
  • This is the phase where the actual project is made. The system‘s software is coded in this phase. Code generation makes the system machine-readable. The code is generated by the technical team of software developers and programmers. The code is generated with the help of languages like C, C++, Java, VB, SQL and tools like debuggers and compilers.
• System Implementation:
  • Here, the system developed is incorporated in the design of the project. The developers assemble their creations in the previous phases of the SDLC.
• System Integration and Testing:
  • The system generated is now checked for errors and bugs so to as to ascertain how workable the system developed really is. The System Testing phase shows whether the timelines of the project can be adhered to or how much work is still pending, depending on the number of errors and bugs found.
• System Acceptance and Installation :
  • Testing in live conditions is an acid test for the system’s success. Testing the project in a replica of live environment will enable the software developing team to ascertain whether the software developed will actually work in live conditions and as per how it was envisioned to work.
• System Maintenance :
  • Once system is implemented in live conditions, it has to be maintained properly. The software developed may face some changes due to some unexpected inputs or changes due to new personnel in the organization. Hence any problems arising need to be fixed to maintain the system well.

What is SDLC (Software Development Life Cycle)?

SDLC or Software Development Life Cycle is the life cycle literally of the development of a system or software.  This life cycle details all the processes that a system undergoes while it is being designed. That is the basic layman understanding of what SDLC stands for.

The steps of the System Development Life Cycle are detailed as below. They show the detailed working of how a system is developed for a particular project.

The Software Development Life Cycle (SDLC) starts when a client expresses the need to start a new project. Once the project is in hand, the steps of the SDLC work as:

• Project Planning:
  • Planning is the core of every process and only effective planning  can make a  Business Analyst realize if the intended system can really be developed or not. A feasibility study is conducted in this stage to determine if the actual system intended is indeed possible to work upon or not.
• System Analysis and Requirements Definition:
  • Here, the requirements of the client in the system to be developed are properly analyzed and then a final requirement definition is written by the Business Analyst in consultation with the client, who will be the end- user of the project.  This requirements definition is used by the software team of programmers and developers to start the project.
• System Design:
  • This is the process of SDLC where the system is actually designed as per the requirements.  The process of database design, structure design, nuances of the client/server technology, defining tiers of package architecture are all defined properly in this phase.
• System Development:
  • This is the phase where the actual project is made. The system‘s software is coded in this phase. Code generation makes the system machine-readable. The code is generated by the technical team of software developers and programmers. The code is generated with the help of languages like C, C++, Java, VB, SQL and tools like debuggers and compilers.
• System Implementation:
  • Here, the system developed is incorporated in the design of the project. The developers assemble their creations in the previous phases of the SDLC.
• System Integration and Testing:
  • The system generated is now checked for errors and bugs so to as to ascertain how workable the system developed really is. The System Testing phase shows whether the timelines of the project can be adhered to or how much work is still pending, depending on the number of errors and bugs found.
• System Acceptance and Installation :
  • Testing in live conditions is an acid test for the system’s success. Testing the project in a replica of live environment will enable the software developing team to ascertain whether the software developed will actually work in live conditions and as per how it was envisioned to work.
• System Maintenance :
  • Once system is implemented in live conditions, it has to be maintained properly. The software developed may face some changes due to some unexpected inputs or changes due to new personnel in the organization. Hence any problems arising need to be fixed to maintain the system well.