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1. PURPOSE
The objectives of the document are to describe
the Rapid Application Development (RAD) task structure and
to detail the procedures involved in conducting RAD projects.
2. SCOPE
The target audience of the document are
those who would adopt the RAD for systems development.
The RAD Procedures Guide is structured according
to the stages of the RAD methodology namely Requirements
Planning, User Design, Rapid Construction and Transition.
For each task in the RAD stage, the following information
is documented:
- Objectives
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- the objectives of performing the task; |
- Description
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- a general description of the task; |
- Prerequisites
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- a list of reference materials; |
- Deliverables
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- a list of deliverables that may be produced; |
- Guidelines
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- the guidelines, if applicable, for accomplishing the task; |
- Techniques
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- a list of applicable techniques; |
- Roles
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- a list of roles that may be involved; and |
- Sub-tasks
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- a graphical representation of the sequence of sub-tasks involved. |
For ease of reference, parts of the contents
are extracted from the document and summarized in the following
sections.
3. RAD OVERVIEW
Rapid Application Development (RAD) refers
to a development life cycle designed to give much faster
development and higher quality systems than the traditional
life cycle. It is designed to take advantage of powerful
development software like CASE tools, prototyping tools
and code generators. RAD is a people-centered and incremental
development approach. Active user involvement, as well as
collaboration and co-operation between all stakeholders
are imperative. Testing is integrated throughout the development
life cycle so that the system is tested and reviewed by
both developers and users incrementally.
The key objectives of RAD are:
- High Speed;
- High Quality; and
- Low Cost.
The RAD life cycle composes of four stages:
- Requirements Planning;
- User Design;
- Rapid Construction; and
- Transition.
3.1 Requirements Planning
(RP)
The objectives of the RP stage are (i) to
establish a general understanding of the business problems
that surround its development and eventual operation; (ii)
to become familiar with existing systems and; (iii) to identify
the business processes that will be supported by the proposed
application.
The RP stage begins with a meeting, or series
of meetings, between the business and IS management. These
meetings initiate the development process by establishing
a mutual understanding of the objectives of the development
project in general and the system in particular.
Business executives, end users and IS professionals,
then, take part in Joint Requirements Planning (JRP) workshops
which progress through a structured set of steps. During
this stage, an outline of the system area and definition
of the system scope are developed.
The tasks of this stage are:
(a) Research Current Situation
This task initiates the RP stage for the
proposed system by researching the current environment.
The information developed in the initial discussions provides
a starting point for this investigation. This research is
conducted for preparing the requirements definition through
JRP workshops. The project team members become familiar
with the current situation by investigating current systems,
the information available in any existing CASE repositories,
and by looking at similar systems for the purpose of looking
for any reusable structures.
(b) Define Requirements
The outline system area model and scope
of the proposed system are developed in this task. The functionality
of the system is expressed in terms of the business processes
and the data that the system will support. Management issues
that affect subsequent development and transition activities
are also identified.
Deliverables of this task are accomplished
via a series of JRP workshops. Participants in these workshops
include the managers of business areas that will be directly
affected by the operation of the proposed system.
(c) Finalize Requirements
In this task, the scope of the proposed
system is formally documented. An estimate of the cost and
duration to implement the system is prepared. Sometimes,
the cost and duration may already be fixed when the project
commences. In this case, the scope must be well defined
such that the project is still viable with the cost and
duration provided. Approval to proceed with the implementation
is then obtained.
3.2 User Design (UD)
The objectives of the UD stage are (i) to
analyze in detail business activities associated with the
proposed system area; (ii) to analyze in detail the business
data associated with the proposed system area; (iii) to
develop the system structure in terms of the automated and
manual functions that will comprise the system; (iv) to
develop proposed screen layouts for the most important automated
functions; (v) to select the appropriate construction approach
for the system and; (vi) to prepare a work plan defining
the steps necessary for transition of the system, the effort
required to perform these steps, and a schedule by which
these steps can be completed.
The UD stage produces a detailed system
area model, an outline system design, and an implementation
plan. End users participating in Joint Application Design
(JAD) workshops perform the analysis and design activities
associated with this stage.
The tasks of this stage are:
(a) Produce Detailed System Area
Model
JAD workshops are conducted to complete
the analysis of the business activities and data associated
with the proposed system, and produce a detailed system
area model. Once the detailed system area model is completed,
it is possible to refine the scope to ensure that the critical
functions will be delivered in the required time frame.
(b) Develop Outline System Design
An outline system design is developed by
the JAD workshop participants using the system area model
that has been completed and confirmed. Upon completion of
the outline design, interactions between procedures (series
of functions) and data are identified. That is, data usage
per function is defined. The deliverables produced in this
task include functions required for the system, reusable
design components to be incorporated into the system design,
system structures and tentative layouts of critical screens
and reports to be supported by the system.
(c) Refine System Design
The design that emerges from the JAD workshops
is reviewed by the project team members and the user design
team. The consistency of the analysis and design is confirmed
via interaction analysis and prototyping. By interaction
analysis, the interactions between functions and data are
analyzed to identify missing/extraneous functions (no data
usage) or data (not used by any function). The completeness
of the detailed system area model and outline system design
is verified. When inconsistencies are resolved, prototypes
of screens are developed and shown to the users for review
and revision. Adjustment to the list of open issues are
then made.
(d) Prepare Implementation Strategies
A plan for the implementation of the system
is developed. The implementation approach is selected after
reviewing the design of the system. To speed up delivery,
parallel development and timebox development can be adopted.
An implementation plan is prepared listing all the tasks
that must be performed to develop the system and convert
it into operational use. An estimate of the effort necessary
to complete each task is made and summarized into an overall
project cost estimate.
(e) Finalize System Design
The outline design of the system and implementation
plan needs to be finalized. Usually JAD workshops are conducted.
Workshop participants suggest changes to the design based
on their experience in reviewing the prototypes and further
research into the system requirements. Open design issues
are discussed and resolved except those with no impact to
the system design such as cultural issues. The implementation
plan for the system is presented and discussed, enabling
workshop participants to point out any unforeseen problems
or invalid assumptions in the plan.
(f) Obtain Approval for Construction
The results of the final JAD workshop are
incorporated into the system design and implementation plan,
and approval to proceed to the Rapid Construction Stage
is sought.
3.3 Rapid Construction (RC)
The objectives of the Rapid Construction
stage are (i) to complete the detailed design of the proposed
system; (ii) to create and test the software that implements
the proposed system; (iii) to generate a system that operates
at an acceptable level of performance; (iv) to prepare documentation
necessary to operate the proposed application; (v) to design,
develop, and test the required transition software and;
(vi) to perform the steps necessary to prepare for the conversion
of the system to production status.
The design of the proposed system, initially
described in the UD stage, is completed in the RC stage,
and application software to implement that design is developed
and tested. Activities to prepare for the transition of
the system to production status are also performed.
The tasks of the RC stage are:
(a) Prepare for Rapid Construction
The development environment is finalized
including workstations and workspace for the system developers,
and the CASE software for their use. Additionally, the database
is designed based on the preliminary data structure developed
in the UD stage.
Finally, the testing strategy for the system
is completed and the acquisition of facilities necessary
to operate the system after it is constructed is initiated.
(b) Construct System
The detailed definition of the design of
each function is completed, based on the requirements of
the future end-users. Software to implement the automated
functions is developed and tested.
(c) Generate Test Data and System
Documents
This task involves developing the necessary
test data that will verify the operational capacity of the
system. This data will be used during the integration, system
and acceptance tests. Documentation explaining how the system
is to be operated by users and computer operations personnel
is produced.
(d) Prepare for Transition
Activities in this task are to prepare for
the subsequent conversion of the application into production
status. These activities include:
- To prepare a detailed work plan for
transition activities and a contingency plan to cover
failure of the converted application;
- To develop software needed to convert
data from existing formats into formats used by the application;
- To develop transition procedures and
arrangements;
- To prepare a user training plan and training
materials; and
- To resolve organizational issues related
to deployment of the new application.
(e) Verify System Construction
The system must be put through a series
of tests to ensure that each component of the system and
the complete system performs according to the user requirements.
3.4 Transition (TR)
The objectives of the TR stage are (i) to
install the system in production operation with minimal
disruption of normal business activity; (ii) to maximize
the effectiveness of the system in supporting the intended
business activities and; (iii) to identify potential future
enhancement.
The system developed in the RC stage becomes
operational in the TR stage. At this time, the developers
prepare existing data for the new system and train users
to operate the new application. They also provide support
to resolve any problems that arise immediately after the
application becomes operational.
The tasks of the TR stage are:
(a) Conduct User Training
Training sessions are conducted to instruct
future users of the new system on how it operates. This
training is completed before the application is placed into
production. The training sessions are based on materials
developed during the RC stage and follow the training plan
that was developed at that time. The training may include
a train-the-trainers program if a large number of users
have to be trained or permanent training is required.
(b) Perform Data Conversion
Information necessary for the operation
of the new system is converted from existing data sources
into a format accessible by the new system. The converted
data is then loaded into the data structures associated
with the system.
(c) Install Production System
Steps necessary to commence operation of
the system in the production environment are performed in
this task. Necessary adjustments to the hardware and system
software configuration are completed, instructions given
to the operations personnel who will be operating the system,
and software libraries loaded with the production versions
of the application software.
(d) Accept System Installation
The new system installation can be regarded
as successful and will be accepted when it operates for
a specified period within defined tolerances for performance,
error rate and usability. This acceptance is based upon
agreements among users, production/operations staff, support
staff, and the information management organization about
schedules, procedures, pricing policies, warranty agreements,
software, and systems documentation.
For further information, you are welcome to
contact us through email enquiry@ogcio.gov.hk
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