Building a new information
system is a planned organizational change.
Information technology can promote various degrees of organizational
change. Four kinds of structural organizational
change that are enabled by information technology include automation,
rationalization, business process redesign, and paradigm shifts. Each of these carries different risks and
rewards. Automation is the most common
form of IT-enabled organizational change.
It is using the computer to speed up the performance of different
tasks. It frequently reveals new
bottlenecks in production and makes the existing arrangement of procedures and
structures painfully cumbersome.
Rationalization of procedures is the streamlining of standard operating
procedures. It is often found in
programs for making a series of continuous quality improvements in products,
services, and operations. Business
process redesign is where business processes are analyzed, simplified, and
redesigned. It reorganizes workflows
combining steps to cut waste and eliminate repetitive, paper-intensive
tasks. Paradigm shift refers to
rethinking the nature of the business and the nature of the organization.
Many businesses are trying
to use information technology to improve their business processes. Organizations are turning to business process
management. This provides a variety of
tools and methodologies to analyze existing processes, design new processes,
and optimize those processes. Companies
practicing business process management go through several steps. The first step is to identify processes for
change. The next step is to analyze existing processes. The third step is to design the new
process. Step four is to implement the
new process. Step five is to
continuously measure the implemented process.
Tools are also provided by software firms to help businesses identify
and document processes requiring improvement, create models of improved
processes, capture and enforce business rules for performing processes, and
integrate existing systems to support new or redesigned processes. Some BPM tools can document and monitor
business processes to help firms identify inefficiencies. BPM tools can also automate some parts of a
business process and enforce business rules so that employees perform that
process more consistently and efficiently.
Another category of tools can help businesses integrate their existing
systems to support process improvements.
They can automatically manage processes across the business, extract
data from various sources and databases, and generate transactions in multiple
related systems.
Systems development are the
activities that go into producing an information system solution to an
organizational problem or opportunity.
It is a structured kind of problem solved with distinct activities. These activities consist of systems analysis,
systems design, programming, testing, conversion, and production and
maintenance.
System analysis is the
analysis of a problem that a firm tries to solve with an information
system. It consists of defining the
problem, identifying its causes, specifying the solution, and identifying the
information requirements that must be met by a system solution. The systems analysis process identifies
several alternative solutions that the organization can pursue and assess the
feasibility of each. The systems analyst
must define the specific information requirements that must be met by the
chosen system solution. The information
requirements of a new system involve identifying who needs what information,
where, when, and how.
Systems design shows how a
system will meet the information requirements as determined by the systems
analysis. It consists of all the
specifications that give the system its form and structure. Systems designer details the system
specifications that will deliver the functions identified during systems
analysis.
Programming is where system
specifications that were prepared during the design stage are translated into
software program code. Testing must be
conducted to ascertain whether the system produces the right results. Testing can be broken down into three types
of activities: unit testing (testing
each program separately in the system), system testing (tests the functioning
of the information system as a whole), and acceptance testing (provides the
final certification that the system is ready to be used in a production
setting). A test plan is then developed
which includes all the preparations for the series of tests. Conversion is the process of changing from
the old system to the new system. Four
main conversion strategies can be employed.
These include the parallel strategy (both the old system and its
potential replacement are run together for a time until everyone is assured
that the new one functions correctly; it is the safest conversion approach),
the direct cutover strategy (replaces the old system entirely with the new
system on tan appointed day; it is a very risky approach), the pilot study
strategy (introduces the new system to only a limited area of the organization),
and the phased approach strategy (introduces the new system in stages, either
by functions or by organizational units).
Documentation showing how the system works from both a technical and
end-user standpoint is finalized during conversion time for use in training and
everyday operations.
During the production stage,
the system is reviewed by both users and technical specialists to determine how
well it has met its original objectives and to decide whether any revisions or
modifications are in order. Once
fine-tuned, the system must be maintained while it is in production to correct
errors, meet requirements, or improve processing efficiency. Maintenance is the changes in hardware,
software, documentation, or procedures to a production system to correct
errors, meet new requirements, or improve processing efficiency. Maintenance is approximately 20 percent
debugging or correcting emergency production problems, 20 percent concerned
with changes in data, files, reports, hardware, or system software, and 60
percent consists of making user enhancements, improving documentation, and
recoding system components for greater processing efficiency.
Structured methodologies and
object-oriented development are two alternative methodologies for modeling and
designing systems. Structured
methodologies are used to document, analyze, and design information systems,
progressing from the highest, most abstract level to the lowest level of
detail. They are process-oriented,
focusing primarily on modeling the processes, or actions that capture, store,
manipulate, and distribute data as the data flow through a system. This method separates data from
processes. The primary tool for
representing a system’s component process and the flow of data between them is
the data flow diagram. It offers a
logical graphic model of information flow, partitioning a system into modules
that show manageable levels of detail, and it specifies the processes or
transformations that occur within each module and the interfaces that exist
between them. Another tool is a data
dictionary. It defines the contents of
data flows and data stores so that systems builders understand exactly what
pieces of data they contain. Also,
software design is modeled using hierarchical structure charts, which is a
top-down chart showing each level of design, its relationship to other levels,
and its place in the overall design structure.
Object-oriented development
uses the object as the basic unit of systems analysis and design. It is based on the concepts of class and
inheritance. Objects belong to a certain
class, or general categories of similar objects. These classes are grouped into hierarchies in
which a subclass inherits the attributes and methods from its superclass.
Computer-aided software
engineering (CASE) is the automation of step-by-step methodologies for software
and systems development to reduce the amounts of repetitive work the developer
needs to do. CASE tools facilitate the
creation of clear documentation and the coordination of team development
efforts. They enforce common methods and
standards, which may discourage their use in situations where organizational
discipline is lacking.
Alternative systems-building
approaches have been developed to deal with the fact that systems differ in
terms of their size and technological complexity and in terms of the
organizational problems they are meant to solve. Such approaches include the traditional systems
life cycle, prototyping, application software packages, end-user development,
and outsourcing.
The systems life cycle is a
phased approach to building a system, dividing systems development into formal
stages. It maintains a formal division
of labor between end users and information system specialists. It is used for building large complex systems
that require a rigorous and formal requirements analysis, predefined
specifications, and tight controls over the system-building process. However, it can be costly, time-consuming,
and inflexible.
Prototyping is the building
an experimental system rapidly and inexpensively for end users to
evaluate. The process of building a
preliminary design, trying it out, refining it, and trying again is known as an
iterative process of systems development.
Prototyping is more explicitly iterative and it actively promotes system
design changes. The four steps of
prototyping are to identify the user’s basic requirements, develop an initial
prototype, use the prototype, and revise and enhance the prototype. Once no more iterations are required, the
approved prototype then becomes an operational prototype that furnishes the
final specifications for the application.
Prototyping encourages intense end-user involvement throughout the
systems development life cycle, however it can miss essential steps in systems
development and may not easily accommodate large quantities of data or a large
number of users in a production environment.
End-user development are
types of information systems developed by end users with little or no formal
assistance from technical specialists.
Fourth-generation languages make this possible. These are software tools that enable end
users to create reports or develop software applications with minimal or no
technical assistance. They tend to be
nonprocedural, or less procedural, than conventional programming languages,
which means they only specify what has to be accomplished rather than provide
details about how to carry out the task.
End-user developed systems can be completed more rapidly than those
developed through the conventional systems life cycle. However, is poses organizational risks
because it occurs outside of traditional mechanisms for information systems
management and control, and when systems are created rapidly, testing and
documentation may be inadequate.
Using software packages that
are common to all business organizations can save a company time and
money. If the software package does not
meet all requirements for an organization, it can be customized. This feature allows a software package to be
modified to meet an organization’s unique requirements without destroying the
integrity of the packaged software. If
the package cannot be customized because the organization’s requirements
conflict with the way the package works, then the organization will have to
adapt to the package and change its procedures.
Outsourcing is contracting
the applications development to external vendors. Firms may use this if they do to want to use
their internal resources to build or operate their information systems. A company could also hire an external vendor
to design and create the software for its system, but that company would operate
the system on its own computers. Outsourcing
vendors may be domestic or in another country.
Domestic outsourcing is driven by the fact that outsourcing firms
possess skills, resources, and assets that their clients do not have and it is
often less expensive. Offshore
outsourcing is more cost-driven and many of these firms offer world-class
technology assets and skills.
In order to keep up with the
digital environment and respond to new opportunities, organizations need to be
able to add, change, and retire their technology capabilities quickly. Fast-cycle techniques such as rapid
application development (RAD), joint application design (JAD), agile
development, and reusable standardized software components allow them to do
so. RAD is the process for developing
systems in a very short time period by using prototyping, fourth generation
tools, and close teamwork among users and systems specialists. JAD is the process to accelerate the
generation of information requirements by having end users and information
systems specialists work together in intensive interactive design
sessions. Agile development focuses on
rapid delivery of working software by breaking a large project into a series of
small subprojects that are completed in short periods of time using iteration
and continuous feedback. Component-based
development enables a system to be built by assembling and integrating existing
software components. Web services can be
used as tools for building new information system applications or enhancing
existing systems. They can perform
certain functions on their own and they can engage other Web services to
complete more complex transactions.
No comments:
Post a Comment