Pertemuan – Matakuliah: M0304/Corporate Information System Management Tahun: 2008

Fakultas Ilmu Komputer Modul-17-2 M ETODOLOGI P ENGEMBANGAN S OFTWARE M ANDIRI

Fakultas Ilmu Komputer Modul-17-3 S YSTEMS D EVELOPMENT L IFE C YCLE M ETHODOLOGY Systems development life cycle (SDLC) – a highly structured approach for development of new customized software applications

Fakultas Ilmu Komputer Modul-17-4 S YSTEMS D EVELOPMENT L IFE C YCLE M ETHODOLOGY The SDLC Steps Figure 17.1 The Systems Development Life Cycle Key characteristic is extensive formal reviews required at end of each major step

Fakultas Ilmu Komputer Modul-17-5 S YSTEMS D EVELOPMENT L IFE C YCLE M ETHODOLOGY The SDLC Steps Figure 17.2 Cost Breakdown for $1 Million SDLC Project Hallmark of SDLC approach: extensive up- front time spent determining requirements to avoid expensive changes later

Fakultas Ilmu Komputer Modul-17-6 S YSTEMS D EVELOPMENT L IFE C YCLE M ETHODOLOGY The SDLC Steps SDLC: – Most often requires a lot of documentation – Outputs from one step inputs to next – Often referred to as the “waterfall” model

Fakultas Ilmu Komputer Modul-17-7

Fakultas Ilmu Komputer Modul-17-8 S YSTEMS D EVELOPMENT L IFE C YCLE M ETHODOLOGY Definition Phase – Requirements Definition Focuses on logical design: processes, data flows, and data interrelationships – not specific physical implementation Deliverable – system requirements document: – Detailed descriptions of inputs and outputs, processes used to convert input data to outputs – Formal diagrams and output layouts – Revised cost/benefit analysis – Revised plan for remainder of project

Fakultas Ilmu Komputer Modul-17-9 S YSTEMS D EVELOPMENT L IFE C YCLE M ETHODOLOGY Construction Phase System Design System Building System Testing Figure 17.3 Characteristics of High Quality Systems Documentation is a major mechanism of communication during development process

Fakultas Ilmu Komputer Modul S YSTEMS D EVELOPMENT L IFE C YCLE M ETHODOLOGY Implementation Phase Installation Operations Maintenance

Fakultas Ilmu Komputer Modul Implementation Phase – Installation Figure 17.4 Implementation Strategies Parallel Strategy

Fakultas Ilmu Komputer Modul Implementation Phase – Maintenance Figure 17.5 Percent of Development Resources Devoted to Maintenance

Fakultas Ilmu Komputer Modul Implementation Phase – Maintenance Figure 17.6 The Widening Gap Between Organization’s Needs and System’s Performance

Fakultas Ilmu Komputer Modul S YSTEMS D EVELOPMENT L IFE C YCLE M ETHODOLOGY The SDLC Project Team Usually temporary Includes personnel from IS and business units Has a project manager – Traditionally from IS – Can be from business unit – May be one from each – Responsible for success of project – delivering quality system on time and within budget

Fakultas Ilmu Komputer Modul S YSTEMS D EVELOPMENT L IFE C YCLE M ETHODOLOGY The SDLC Project Team Includes systems analysts – Have critical roles – Work closely with business managers and end users – Have problem-solving skills, knowledge of IT capabilities, strong business understanding Has a business sponsor and a champion

Fakultas Ilmu Komputer Modul S YSTEMS D EVELOPMENT L IFE C YCLE M ETHODOLOGY Managing an SDLC Project Characteristics critical for success: – Manageable project size – Accurate requirements definition – Executive sponsorship

Fakultas Ilmu Komputer Modul S YSTEMS D EVELOPMENT L IFE C YCLE M ETHODOLOGY Figure 17.7 Costs of Error Correction by SDLC Step Managing an SDLC Project (Adapted from Boehm, 1976)

Fakultas Ilmu Komputer Modul S YSTEMS D EVELOPMENT L IFE C YCLE M ETHODOLOGY SDLC Advantages and Disadvantages Figure 17.8 Advantages and Disadvantages of Traditional SDLC Approach

Fakultas Ilmu Komputer Modul P ROTOTYPING M ETHODOLOGY Prototyping approach: – Takes advantage of availability of fourth generation procedural languages and relational database management systems – Enables creation of system (or part of system) more quickly, then revise after users have tried it – Is a type of evolutionary development process

Fakultas Ilmu Komputer Modul P ROTOTYPING M ETHODOLOGY Prototyping examples: – Input and output screens developed for users to test as part of requirements definition – “First-of-a-series” – a completely operational prototype used as a pilot – “Selected features” – only some essential features included in prototype, more added later – Prototyping used as a complete alternative to traditional SDLC methodology

Fakultas Ilmu Komputer Modul P ROTOTYPING M ETHODOLOGY Prototyping used as a complete alternative to traditional SDLC methodology: – Good when requirements hard to define – Good when system needed quickly – Impractical for large, complex applications

Fakultas Ilmu Komputer Modul The Prototyping Steps Figure 17.9 The Prototyping Life Cycle

Fakultas Ilmu Komputer Modul P ROTOTYPING M ETHODOLOGY Representatives from IS and user management necessary Need team members who can quickly build systems using advanced tools Requires dedicated business user roles The Prototyping Project Team

Fakultas Ilmu Komputer Modul P ROTOTYPING M ETHODOLOGY Advantages: – Only basic requirements needed at front end – Used to develop systems that radically change how work is done, so users can evaluate – Allows firms to explore use of new technology – Working system available for testing more quickly – Less strong top-down commitment needed at front end – Costs and benefits can be derived after experience with initial prototype – Initial user acceptance likely higher Prototyping Advantages and Disadvantages

Fakultas Ilmu Komputer Modul P ROTOTYPING M ETHODOLOGY Disadvantages: – End prototype often lacks security and control features – May not undergo as rigorous testing – Final documentation may be less complete – More difficult to manage user expectations Prototyping Advantages and Disadvantages

Fakultas Ilmu Komputer Modul P ROTOTYPING M ETHODOLOGY Prototyping within an SDLC Process Figure SDLC with Prototyping to Define Requirements

Fakultas Ilmu Komputer Modul P ROTOTYPING M ETHODOLOGY Prototyping within an SDLC Process Figure Prototyping/Piloting Replaces SDLC Definition Phase

Fakultas Ilmu Komputer Modul N EWER A PPROACHES Rapid Application Development (RAD) Figure Four-Step RAD Cycle Hybrid methodology – aspects of SDLC and prototyping Goal is to produce a system in less than a year

Fakultas Ilmu Komputer Modul N EWER A PPROACHES Rapid Application Development (RAD) Joint application design (JAD) – a technique in which a team of users and IS specialists engage in an intense and structured process in order to minimize the total time required for gathering information from multiple participants

Fakultas Ilmu Komputer Modul N EWER A PPROACHES Rapid Application Development (RAD) Joint application design (JAD) – a technique in which a team of users and IS specialists engage in an intense and structured process in order to minimize the total time required for gathering information from multiple participants Computer-aided software engineering (CASE) – any software tool used to automate one or more steps of a software development methodology

Fakultas Ilmu Komputer Modul N EWER A PPROACHES Rapid Application Development (RAD) Figure Types of CASE Tools (Adapted from Valacich, George, and Hoffer, 2001)

Fakultas Ilmu Komputer Modul N EWER A PPROACHES Rapid Application Development (RAD) Figure RAD Advantages and Disadvantages

Fakultas Ilmu Komputer Modul N EWER A PPROACHES Agile Software Development Discipline Alternative methodology for smaller projects Based on four key values: – Simplicity – Communication – Feedback – Courage One type: Extreme Programming (XP) – Programmers write code in pairs – Use simple design and frequent testing

Fakultas Ilmu Komputer Modul M ANAGING S OFTWARE P ROJECTS U SING O UTSOURCED S TAFF Advantages: – Helps keep software development costs down – Uses technical expertise not available in-house – Can often complete projects more quickly Off-site outsourcing: – Onshore – within same country or region – Offshore – not within same country or region

Fakultas Ilmu Komputer Modul M ANAGING S OFTWARE P ROJECTS U SING O UTSOURCED S TAFF Offshore alternative good option when: – System requirements well-defined and remain stable – Time is of essence and 7x24 hour availability of resources a good idea – Cost of project important

Fakultas Ilmu Komputer Modul M ANAGING S OFTWARE P ROJECTS U SING O UTSOURCED S TAFF Guidelines for managing offsite outsourcer: – Manage expectations, not staff – Take explicit actions to integrate the offsite workers – Communicate frequently – Abandoning informal ways may result in increased rigor

Fakultas Ilmu Komputer Modul Reff-Haag Prosedure Outsource

Modul OUTSOURCING Developing strategic partnerships Outsourcing - the delegation of specific work to a third party for a specified length of time, at a specified cost, and at a specified level of service

Modul Developing Strategic Partnerships

Modul Developing Strategic Partnerships IT outsourcing takes on 1 of 4 forms: 1. Purchasing existing software 2. Purchasing existing software and pay the publisher to make certain modifications 3. Purchasing existing software and pay the publisher for the right to make modifications yourself 4. Outsourcing the development of an entirely new and unique system for which no software exists

Modul The Outsourcing Process

Modul The Outsourcing Process Steps of the outsourcing process 1. Planning 2. Define project scope 3. Select a target system 4. Establish logical requirements

Modul The Outsourcing Process 5. Develop a request for proposal Request for proposal (RFP) - a formal document that describes in detail your logical requirements for a proposed system and invites outsourcing organizations to submit bids for its development 6. Evaluate request for proposal returns and choose a vendor 7. Test and accept solution 8. Monitor and reevaluate

Modul The Outsourcing Process – an RFP

Modul Offshore Outsourcing  Offshore outsourcing - using organizations from other countries to write code and develop systems

Modul The Advantages of Outsourcing Focus on unique core competencies Exploit the intellect of another organization Better predict future costs Acquire leading-edge technology Reduce costs Improve performance accountability

Modul The Disadvantages of Outsourcing Reduces technical know-how for future innovation Reduces degree of control Increases vulnerability of strategic information Increases dependency on other organizations