Why require to develop sisten information?

system development can mean to compile a[n system [of] a[n new system to replace the system old ones as a whole or improve;repair the system which there have. system old ones require to be improve;repaired or changed [by] the disebakan [of] because several things, that is as follows:

Ø Existence of Problems ( problems)

Ø Ketidakberesan in Organizational Growth System

Ø To Reach for the opportunity ( opportunities)

Ø Existence of instruction ( directives)

System Development Target

v Solving problems

v Reach for the opportunity

v Fulfilling given instruction

What expected new system?

· Performance ( performance)

- Measured to use the throughput and response time

· Information ( information)

- Make-Up of information quality

· Economy ( economic)

- Make-Up of benefit of vs decreasing cost

· Control ( operation)

- Detecting and improve;repairing mistake

· Efficiency ( efficiency)

- Efficient [of] operational

· Services ( service)

- Make-Up of system service

System development phase:

1. System planning

2. System analysis

3. System design

4. System selection

5. System implementation and maintenance

System development life cycle with step-step utama

System planing

System analis

Design (general)

Evalution and selection

Design (terinci)

System implemention

System maintenance

front

end Masing-masing \

phase Siklus menghasilkan

sebagai

back

end

phase

Systems Development Life Cycle

System development life cycle or software development life cycle in system engineering and software engineering refers to the process of creating or altering systems, and the models and methodologies that people use to develop these systems. The concept generally refers to computer or information systems

In systems engineering and software engineering refers to the process of creating or altering systems, and the models and methodologies that people use to develop these systems. The generally refers to computer or information systems.

Overview Systems Development Life Cycle (SDLC) is any logical process used by a systems analyst to develop an information systems. Including requirements, validation, training, and user ownership. An SDLC should result in a high quality system that meets or exceeds customer expectations, reaches completion within time and cost estimates, works effectively and efficiently in the current and planned Information Technology infrastructure, and is inexpensive to maintain and cost-effective to enhance. Computer systems have become more complex and often (especially with the advent of Service-Oriented Architecture) link multiple traditional systems potentially supplied by different software vendors. To manage this level of complexity, a number of system development life cycle (SDLC) models have been created: “waterfall,” “fountain,” “spiral,” “build and fix,” “rapidprototyping,” “incremental,” and “synchronize and stabilize.” Although the term SDLC can refer to various models, it typically denotes a waterfall methodology. In project management a project has both a life cycle and a “systems development life cycle,” during which a number of typical activities occur. The project life cycle (PLC) encompasses all the activities of the project, while the systems development life cycle focuses on realizing the product requirements. History Systems development life cycle is the oldest formalized methodology for building informatio systems, intended to develop information systems in a very deliberate, structured and methodical way, reiterating each stage of the life cycle. The traditional systems development life cycle originated in the 1960s to develop large scale functional business systems in an age of large scale business conglomerates. Information systems activities resolved around heavy data processing and number crunching routines. In the 1980s the Structured Systems Analysis and Design Method (SSADM) was based in SDLC. SSADM is a systems approach to the analysis and design of information systems, produced for the Office of Government Commerce, a UK government office concerned with the use of technology in government. Since the 1980s the traditional life cycle approaches to systems development has been increasingly replaced with alternative approaches and frameworks, which attempted to overcome some of the inherent deficiencies of the traditional SDLC. System development phase.

Systems Development Life Cycle (SDLC) adheres to important phases that are essential for developers, such as planning, analysis, design, and implementation, and are explained in the section below. There are several Systems Development Life Cycle Models in existence. The oldest model, that was originally regarded as “the Systems Development Life Cycle” is the waterfall model a sequence of stages in which the output of each stage becomes the input for the next. These stages generally follow the same basic steps but many different waterfall methodologies give the steps different names and the number of steps seems to vary between 4 and 7. There is no definitively correct Systems Development Life Cycle model, but the steps can be characterized and divided in several steps.

Planning

To generate a high-level view of the intended project determine the goals of the project. The feasibility study is sometimes used to present the project to upper management in an attempt to gain funding. Projects are typically evaluated in three areas of feasibility: economical, operational, and technical. Furthermore, it is also used as a reference to keep the project on track and to evaluate the progress of the MIS team.^[6] The MIS is also a complement of those phases. This phase is also called the analysis phase.

Analysis

The goal of systems analysis is to determine where the problem is in attempt to fix the system. This step involves breaking down the system in different pieces and drawing diagrams to analyze the situation. Analysts project goals, breaking down functions that need to be created, and attempt to engage users so that definite requirements can be defined.

Design

In systems design functions and operations are described in detail, including screen layouts, business rules, process diagrams and other documentation. The output of this stage will describe the new system as a collection of modules or subsystems.

Testing

The code is tested at various levels in software testing. Unit, system and user acceptance testing are often performed. This is a grey area as many different opinions exist as to what the stages of testing are and how much if any iteration occurs. Iteration is not generally part of the waterfall model, but usually some occurs at this stage.

Types of testing:

• Data set testing
• Unit testing
• System testing
• Black box testing
• White box testing
• Module testing
• Regression testing
• Automatic testing
• User acceptaing testing

Operations and Maintenance

The deployment of the system includes changes and enhancements before the decommissioning or sunset of the system. Maintaining the system is an important aspect of SDLC. As key personnel change positions in the organization, new changes will be implemented, which will require system updates. Model Waterfall

Waterfall model

The waterfall model is a sequential development process, in which development is seen as flowing steadily downwards (like a waterfall) through the phases of requirements analysis, design, implementation, testing (validation), integration, and maintenance. The first formal description of the waterfall model is often cited to be an article published by Winston W. Royce in 1970 although Royce did not use the term “waterfall” in this article. Basic principles of the waterfall model are:

Ø Project is divided into sequential phases, with some overlap and splashback acceptable between phases.

Ø Emphasis is on planning, time schedules, target dates, budgets and implementation of an entire system at one time.

Ø Emphasis is on planning, time schedules, target dates, budgets and implementation of an entire system at one time.

Model spiral (RAD) Rapid Application Development (RAD) is a software development methodology, which involves iterative development and the construction of prototypes. Rapid application development is a term originally used to describe a software development process introduced by James Martin in 1991. Basic principles:

Ø Key objective is for fast development and delivery of a high quality system at a relatively low investment cost.

Ø Attempts to reduce inherent project risk by breaking a project into smaller segments and providing more ease-of-change during the development process.

Ø Aims to produce high quality systems quickly, primarily through the use of iterative Prototyping (at any stage of development), active user involvement, and computerized development tools. These tools may include Graphical User Interface (GUI) builders, Computer Aided Software Engineering (CASE) tools, Database Management Systems (DBMS), fourth-generation programming languages, code generators, and object-oriented techniques.

Ø Key emphasis is on fulfilling the business need, while technological or engineering excellence is of lesser importance.

Ø Project control involves prioritizing development and defining delivery deadlines or “timeboxes”. If the project starts to slip, emphasis is on reducing requirements to fit the timebox, not in increasing the deadline.

Ø Generally includes Joint Application Development (JAD), where users are intensely involved in system design, either through consensus building in structured workshops, or through electronically facilitated interaction.

Ø Active user involvement is imperative.

Ø Iteratively produces production software, as opposed to a throwaway prototype.

Ø Produces documentation necessary to facilitate future development and maintenance.

Ø Standard systems analysis and design techniques can be fitted into this framework.

Model spiral

Spiral

The spiral model is a software development process combining elements of both design and prototyping-in-stages, in an effort to combine advantages of top-down and bottom-up concepts. Basic principles:

Ø Focus is on risk assessment and on minimizing project risk by breaking a project into smaller segments and providing more ease-of-change during the development process, as well as providing the opportunity to evaluate risks and weigh consideration of project continuation throughout the life cycle.

Ø Each cycle involves a progression through the same sequence of steps, for each portion of the product and for each of its levels of elaboration, from an overall concept-of-operation document down to the coding of each individual program.

Ø Each trip around the spiral traverses four basic quadarants: (1) determine objectives, alternatives, and constrainst of the iteration; (2) Evaluate alternatives; Identify and resolve risks; (3) develop and verify deliverables from the iteration; and (4) plan the next iteration.

Ø Begin each cycle with an identification of stakeholders and their win conditions, and end each cycle with review and commitment.

Model iterative

System development approach.

· Classic approach [of] vs of structure approach

· approach of Rasher of vs of system approach

· approach of Bawah-Naik vs of approach atas-turun

· approach of Sistem-Menyeluruh vs of approach moduler

· Approach [of] jumping movement far vs approach expand

System development Approach.

v Classic approach [of] vs of structure approach

- Classic approach

· Step in SDLC

· [Do] not involve the consumer, more emphasizing [of] system analyst

· Problems: difficult development, costly treatment expense, big mistake possibility, efficacy less be well guaranted, internal issue applying

- Structure approach

· Consumer involved from early to determine the system requirement

· Using tools-tools of] like data of flow diagram

Approach of Rasher system approach.

- Rasher approach

· Emphasizing at a[n application or activity

Heedless of the target of[is overall of

System approach

· See system as one intact union

· Emphasizing at goal achievement as a whole

Approach of bottom-up vs of approach top-down

- approach bottom-up

· Started from level of under that is operational

· Representing approach marking classical

· Recognized with the term data-analysis

- approach top-down

· Started from level for that is strategy planning

· Representing marking of structure approach

· Recognized also by decision-analysis

Approach of all system vs approach moduler

- approach all system

· Developing system at a time and totally

· Representing classic approach marking

- approach moduler

· Breaking complicated system become the parts of simple

· System developed become on schedule, easy to to be comprehended and looked after

v Representing marking of structure approach

- approach of great loop vs approach expand the

· great-loop approach

· Developing system at a time use the sophisticated technology

· High risk and finish a lot of expense

- Approach expand the ( evolutionary approach)

· Applying sophisticated technology for the application of certain

· Developed to follow the requirement

· Cost effective and can keep abreast of technology

System development methodologies.

What that methodologies?

- Method used in science

What is method?

- A[N way of systematic to do something

What that algorithm?

Procedure medley to solve an problem

Classification of development Methodologies.

v Functional Decomposition

- Emphasizing system resolving become the subsistem

- Follow the example of the: HIPO, Stepwise Refinement, iterative stepwise refinement, information hiding

v Data-Oriented

- Emphasizing at processed data characteristic

· Data-flow Oriented: module [of] according to data element type

· Data-structure Oriented: structure of input and output

v Prescriptive

- [Is] usually provided by factory of software maker

Appliance in system development.

· In form of graph: HIPO, SADT, Jackson’S Diagram, and others

· Appliance using schema:

- Activity Charting: depicting activity, follow the example of the: Gant Chart, flowchart.

- Layout Charting: depicting

- Personal Relationship charting: depicting personnel relation/link, follow the example of the: organization chart, working distribution chart

System development Technique.

· technique of project Management ? for the schedule of project, follow the example of the: CPM And PERT

· Technique find the fact ? to collect and determine the data / fact

- Interview the

- Observation

· Technique analyse the expense / benefit ? cost-benefit and cost-effectiveness analysis

· Technique run the meeting

· Inspection technique

System Analyst & Pemrogram.

· System analyst: learning problem and determine the requirement of system wearer to identify the resolving

· programer: writing code program pursuant to designing to devel/build which is]made by by a analyst

· System analyst undertake to link the knowledge difference that happened among/between wearer of system and programer

Needed knowledge.

· data processing Technology, Computer and programmer

· Business knowledge in general

· Quantitative method: regresi, linear programming,

· Trouble-Shooting membership

· Communications Membership usher the personnel

· Membership construct the usher personnel