Introduction to Information Systems PDF

Introduction to Information Systems Rainer, Prince, Sanchez-Rodriguez, Splettstoesser Hogeterp, Ebrahimi Fifth Canadian Edition Chapter 13 Acquiring Information Systems and Applications Copyright ©2021 John Wiley & Sons Canada, Ltd. ...

Introduction to Information Systems Rainer, Prince, Sanchez-Rodriguez, Splettstoesser Hogeterp, Ebrahimi Fifth Canadian Edition Chapter 13 Acquiring Information Systems and Applications Copyright ©2021 John Wiley & Sons Canada, Ltd. Learning Objectives 1. Discuss the business decisions that companies must make when they acquire new applications 2. Enumerate the primary tasks and the importance of each of the six processes involved in the systems development life cycle 3. Describe alternative development methods and the tools that augment these methods Copyright ©2021 John Wiley & Sons Canada, Ltd. 2 Chapter Outline 1. Strategies for Acquiring IT Applications 2. Traditional Systems Development Life Cycle 3. Alternative Methods for Systems Development Copyright ©2021 John Wiley & Sons Canada, Ltd. 3  13.2 Strategies for Acquiring IT Applications (1 of 2) Fundamental decisions in acquiring IT applications o How much computer code does the company want to write? o How will the company pay for the application? o Where will the application run? Purchase a prewritten application- designed by vendors Customize a prewritten application- ask the vendor to tweak it for you. Lease the application- use application service provider or software as a service vendor. Subscription service. Application service providers (ASP) and Software-as-a- Service (SaaS) vendors Copyright ©2021 John Wiley & Sons Canada, Ltd. 4 13.2 Strategies for Acquiring IT Applications (2 of 2) Use open-source software- free of charge. In house expertise. Outsourcing- the use of an external entity to help you carry out software development tasks. o Onshore- the use of same companies in same country as the business to produce software. o Nearshore- using nearby countries.. o Offshoring- far away. End-user development- use of workers in an organization who do not posses IT skills Copyright ©2021 John Wiley & Sons Canada, Ltd. 5 TABLE 13.1 Advantages and Limitations of the Buy Option Advantages Many different types of off-the-shelf software are available. The company can try out the software before purchasing it. The company can save a lot of time by buying rather than building. The company can know what it is getting before it invests in the product. Purchased software may eliminate the need to hire personnel specifically dedicated to a project. Disadvantages Software may not exactly meet the company’s needs. Software may be difficult or impossible to modify, or it may require huge business process changes to implement. The company will not have control over software improvements and new versions. Purchased software can be difficult to integrate with existing systems. Vendors may discontinue a product or go out of business. Software is controlled by another company with its own priorities and business considerations. The purchasing company lacks intimate knowledge about how and why the software functions as it does. Copyright ©2021 John Wiley & Sons Canada, Ltd. 6 FIGURE 13.2 Operation of an application service provider Copyright ©2021 John Wiley & Sons Canada, Ltd. 7 FIGURE 13.3 Operation of a Software- as-a-Service vendor Copyright ©2021 John Wiley & Sons Canada, Ltd. 8 13.3 Traditional Systems Development Life Cycle Systems development life cycle (SDLC) stages: o Systems Investigation or Planning o Systems Analysis o Systems Design o Systems Programming o Systems Testing o Systems Implementation o Systems Maintenance PADPTIM Copyright ©2021 John Wiley & Sons Canada, Ltd. 9 Figure 9.1 The SDLC and Its Associated Activities Systems development life cycle (SDLC) – The overall process for developing information systems. It starts with systems planning and ends with systems maintenance in the initial iteration. Copyright ©2021 John Wiley & Sons Canada, Ltd. 10 The Traditional Systems Development Life Cycle (SDLC) Team Users Systems analysts Programmers Technical specialists Top management (i.e., directors) Copyright ©2021 John Wiley & Sons Canada, Ltd. 11 SDLC: Systems Investigation/Planning Establishes a high-level plan of the intended project and determines project goals Brainstorming takes place at this phase. Three basic solutions are deal with: o Do nothing and continue to use the existing system unchanged; Modify or enhance the existing system; Develop a new system Feasibility studies (Technical, Economic, Behavioral) are carried out Steering committee provides support for the project. Oversee project progress. Change agent is chosen Copyright ©2021 John Wiley & Sons Canada, Ltd. 12 SDLC: Systems Analysis Involves systems analysts examining and analyzing end- user business requirements and refining project goals into defined functions and operations of the intended system Deliverable: o A set of system requirements (i.e., user requirements) Copyright ©2021 John Wiley & Sons Canada, Ltd. 13 SDLC: Systems Design Describes how the system will resolve the business problem Establishes descriptions of the desired features and operations of the system including screen layouts, business rules, process diagrams, pseudo code, and other documentation Deliverable: o A set of technical system specifications that specify: System outputs, inputs, calculations or processing, and user interfaces Hardware, software, databases, telecommunications, personnel, and procedures A blueprint of how these components are integrated Copyright ©2021 John Wiley & Sons Canada, Ltd. 14 SDLC: Systems Programming Involves taking all of the detailed design documents from the design phase and transforming them into the actual system. Programming: translating the design specifications into computer codes Programming languages are used to create the programs/systems. Copyright ©2021 John Wiley & Sons Canada, Ltd. 15 SDLC: Systems Testing Involves bringing all the project pieces together into a special testing environment to eliminate errors and bugs, and verify that the system meets all of the business requirements defined in the analysis phase Testing: assesses whether the computer codes written for the program produces the expected and desired results. o It is intended to detect errors or debug computer codes. Copyright ©2021 John Wiley & Sons Canada, Ltd. 16 The Systems Development Life Cycle (SDLC) Copyright ©2021 John Wiley & Sons Canada, Ltd. 17  SDLC: Systems Implementation Implementation (i.e., deployment): the process of converting from an old computer system to a new one. Involves placing the system into production so users can begin to perform actual business operations with it. Implementation or conversion strategies: o Direct conversion- old system is completely replaced by new one o Pilot conversion- new system is implemented in a small part o Phased conversion- new system is introduced in stages o Parallel conversion- new system and old system run simultaneously. Copyright ©2021 John Wiley & Sons Canada, Ltd. 18 SDLC: Systems Maintenance Involves performing changes, corrections, additions, and upgrades to ensure the system continues to meet its business goals. It is required to keep a computer system running properly. There are four types of corrections. - Corrective- changes to design flaws - Adaptive- changes to functionality - Perfective- improve performance/interface - Preventive- preventing system failure Copyright ©2021 John Wiley & Sons Canada, Ltd. 19 Alternative Methods of Systems Development Joint application design (JAD) Rapid application development (RAD) Agile development - SCRUM End-user development DevOps Copyright ©2021 John Wiley & Sons Canada, Ltd. 20 Alternative Methods of Systems Development - JAD Joint application design (JAD) Joint application design is a term originally used to describe a software development process pioneered and deployed during the mid-1970s. JAD is a popular fact-finding technique that brings users into the development process as active participants. Copyright ©2021 John Wiley & Sons Canada, Ltd. 21 Alternative Methods of Systems Development - RAD Rapid application development (RAD) RAD is a methodology for fast application production using an iterative software development process. It uses continuous user feedback It focuses on producing swift prototypes. Copyright ©2021 John Wiley & Sons Canada, Ltd. 22 FIGURE 13.6 A rapid prototyping development process versus SDLC Copyright ©2021 John Wiley & Sons Canada, Ltd. 23 Alternative Methods of Systems Development – Agile development Agile development is a broad term that refers to any project management methodology that uses an iterative and flexible approach. Scrum is an agile team collaboration framework commonly used in software development and other industries. Scrum prescribes teams to break work into goals to be completed within time-boxed iterations, called sprints. Each sprint is no longer than one month and commonly lasts two weeks. The scrum team assesses progress in time- boxed, stand-up meetings of up to 15 minutes, called daily scrums Copyright ©2021 John Wiley & Sons Canada, Ltd. 24  Alternative Methods of Systems Development – End-user development End-user development (EUD) or end-user programming (EUP) refers to activities and tools that allow end-users – people who are not professional software developers – to program computers or develop their own programs. Microsoft Excel is probably the most widely used end-user development application. Workers around the world make use of functions, macros, and other tools every day. Simple video game engines like RPG Maker are accessible to non-programmers. A variety of tools collectively known as “no code” platforms make it possible to develop apps without programming knowledge of any kind. Copyright ©2021 John Wiley & Sons Canada, Ltd. 25 Alternative Methods of Systems Development – DevOps DevOps – It is a combination (and a portmanteau) of the terms and concepts: "development" and "operations“. DevOps is a methodology in the software development and IT industry. It uses a set of practices and tools to automate the work of software development (Dev) and IT operations (Ops) to improve and shorten the systems development life cycle. Copyright ©2021 John Wiley & Sons Canada, Ltd. 26 Alternative Methods of Systems Development – DevOps SDLC focuses on how the application is designed and built; DevOps aims to shift ownership of each application's production environment away from traditional IT teams and into the hands of the developers; This allows developers to focus on automating as many build, test, and release processes as possible. Copyright ©2021 John Wiley & Sons Canada, Ltd. 27 Copyright Copyright © 2021 John Wiley & Sons Canada, Ltd. or the author. All rights reserved. Students and instructors who are authorized users of this course are permitted to download these materials and use them in connection with the course. No part of these materials should be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, except as permitted by law. Advice on how to obtain permission to reuse this material is available at http://www.wiley.com/go/permissions. Copyright ©2021 John Wiley & Sons Canada, Ltd. 28