© 2009 Pearson Education, Inc. Publishing as Prentice Hall System Development Chapter 9 & 10...

© 2009 Pearson Education, Inc. Publishing as Prentice Hall

System Development

Chapter 9 & 10Information Systems

Management in Practice

8th Edition

© 2009 Pearson Education, Inc. Publishing as Prentice Hall 9-2

Today’s Lecture

Foundations of Systems Development System Integration Project Management Measuring Benefits


Introduction

1970s: System Development Lifecycle (SDLC) Improved process of building system (methodical)

1980s: “Friendly” 4GL (algorithms to solve problems) Reduces programming effort SQL, Postscript, SAS, MathLab, Cold Fusion

1990s: Business Process Reengineering ERP

Late 1990s and 2000s: Internet-based systems Networks and open systems Internet centricity (Web services)


Foundations of Systems Development


Structured Development

Systems development a “craft” in the early years More art than science

Evolved to a structured process in 1970s Took a more scientific approach 3GL, DBMS, mainframes, professional

programmers, well-defined processes Classical Waterfall approach

Much touted but rarely used in its pure form


Waterfall Approach


Structured Development cont’d

Structured development methodologies accompanied this SDLC, characterized by: Discipline (Best practices) Modularity (Divide and conquer) Reliability (few errors) Efficient use of resources (Cost effectiveness)


Fourth-Generation Languages

4GL & Prototyping developed in early 1980s 4GL is more than a computer language. They are

programming environments 4GL facilitated:

Development of some programs by end users Use of different development methods

(prototyping) Focus on problem-solving and system design

rather laborious ‘coding’ – automated coding


Software Prototyping

A software prototype is a live “work-in-progress” system that may be implemented as an actual production system of some variant

An iterative process to test assumptions and gather feedback about: User requirements Application design Program logic

Quick and relatively inexpensive method for system development Xtreme Programming (agile method)


Computer-Aided Software Engineering

CASE developed in 1980s: Automation of 1970s structured development techniques to reduce tediousness and maintenance costs

CASE tools help quickly design, develop, deploy and maintain software

CASE environment includes: Information repository (database) Front-end tools for planning through design Back-end tools for generating code Development workstation


Computer-Aided Software Engineering cont’d

Timeboxing CASE technique used to guarantee delivery of a

system within a fixed period (120 days) Rapid Application Development (RAD):

IS departments that aim for speed over complexity also employ RAD (based on concept of prototyping) to complement CASE


Dupont Cable Management Services

Case example: CASE and RAD Needed a software system to manage its telephones

and voice network systems throughout offices Use CASE and timeboxing to build a custom system

Day 1: Go ahead Day 2-30: Defining components of system Day 31-90: Designing the specifications, developing prototype Day 91-120: Installed the system, followed by second timebox

Final production system took 9 months, vis-à-vis 2-3 years in other firms


Object-Oriented Development

OO development introduced a radical change in systems development in the late 1980s

Modular nature (crux of OO) Code packaging technique

Objects (with specific attributes) Methods (to access attributes of objects) Programming in JAVA

Point-and click programming (GUI) Visual programming (e.g., Visual Basic)


Client-Server Computing

Discussed in earlier chapters Early 1990s architecture

More flexibility than mainframe systems Workload (processing) split between client and

server Integration of pizzazz of the PC world with

the necessary back-end production strengths of the mainframe world


System Integration

Systems integration poses the biggest problem to IS Complex Expensive Risky

Number of products can help facilitate the integration of systems DBMS (e.g., Oracle) ERP (e.g., SAP) Middleware


ERP Systems

ERP provides the means to integrate business departments and functions across an organization (business ‘streams’) Single vendor (e.g. SAP) Single set of applications Single database

Many successes and failures historically Functionality (<59%) Completed on time and within budget (<10%) Business value? (“technical myopism” common)


Middleware

Middleware is a class of software products that enables IS to integrate disparate systems (“translator”)

Variety of applications Different platforms Legacy systems with newer systems

Middleware used for several functionalities Data sharing Transactions Security Software distribution and synchronization


Interorganizational System Development

Business ecosystems Groupings of businesses working together to reduce costs

and time across value chains Supply chain management systems (SCM) Requires teams from different organizations to work

together

Platform (another type — service provider role) Provides infrastructure for the operation of a business

ecosystem SABRE reservation system and more recently Amazon

Web Services


ExxonMobil

Case Example: Platform Mobil created SpeedPass in 1996

1.5”-long keychain gadget that enables customers to wave at a reader when paying for gas

Objective was to “speed” motorists in and out Business Value

Improved customer satisfaction (convenience) 5 million SpeedPass holders to date Speedpass holders purchase more Mobil gas and more

frequently


ExxonMobil cont’d

Case Example: Platform To leverage the technology, Mobil teamed up

with McDonald’s restaurants in Chicago to test the use of SpeedPass to pay for food

Plans to develop similar partnerships with other chains Create network externalities (increase value of

SpeedPass) Can Mobil do more? Is technology imitable?


Internet-Based Systems

Internet-based systems are where the system development action is occurring.

Examine three aspects and instances: Framework

Application Servers Language

Java Environment

Web Services


Application Servers

Preferred framework for developing Internet-based systems

Architecture Virtual server takes requests, runs business logic, and

provides connectivity to back-end systems Goal

Automate and manage technical tasks in development and running of Internet-based applications

Result Developers can focus more on business issues, rather than

technical details


Application Servers

FIGURE 9-4 An Application Server Architecture


Java

“Platform independent” promise “Write once, run anywhere” But poor compatibility with other languages, e.g. C++

Evolved into standard platform for developing server-side applications Enterprise Java Beans (EJB) Java 2 Enterprise Edition (J2EE)

Powerful starting point for building online systems Multivendor platform capability Pre-built package Reusable components


Building a Web Service

Case Example: Web Services Building a Web-based currency converter

1. Expose the code

2. Write a service description

3. Publish the service

4. Find a currency conversion Web service

5. Invoke a Web service


Building a Web ServiceFIGURE 9-5 Building a Web service


Contingencies for Building a Web Service

Preparing for On-The-Fly Web Service Dev Today’s killer app cannot fulfill tomorrow’s needs

Develop scalable and adaptable systems Personal silos of data and apps and intertwining

of a variety of Web Services IS must devise schemes and implement systems to

manage these inevitabilities


Conclusion

Evolution of system development Craft (1960s) Discipline, control and efficiency (1970s) Better development tools and methods (1980s) Client-server, integration, Internet-based systems

(1990s-2000s) Today: Focus on interorganizational systems and

Internet-based systems Role of IS even more salient (project management)

© 2009 Pearson Education, Inc. Publishing as Prentice Hall

MANAGEMENT ISSUES IN SYSTEMS DEVELOPMENT

Chapter 10


Project Management

Project is a collection of related tasks and activities undertaken to achieve a specific goal within a finite time period (temporal)

IT projects are similar to other forms but arguably more difficult Intangibility (you cannot see it or feel it!)

People become confused and concerned

IT project management Coordination (managing interdependencies)


Scope: Job of a Project Manager

Getting the project started Managing the schedule Managing the budget Managing the benefits Managing the risks, opportunities and issues Soliciting feedback and formative evaluation


Change Management

Beyond technical aspects of system Managing change (people side of system)

Assimilation of new systems into work processes Resistance (organizational inertia)

ODR a methodology to manage technology-triggered change (stakeholders involved) Sponsor Change agent Target


Risk Management

Management of risks in IT projects crucial Technical risk

Sub-performance; scope creep Business risk

IT-triggered organizational change not as planned

Risk management “cookbook”1. Assess the risk

2. Mitigate the risk

3. Adjust project management approach


Risk Management cont’d

1. Assess change risks (predominant factors) Leadership

Project leader should be business executive How does project leadership affect outcome?

Employees’ perspective How would they react and why?

Scope and urgency Is the scope too wide? How urgent?

Gibson’s “plus-minus” decision tree





2. Mitigate the risks Risk avoidance

Identify and eliminate source of perceived risk Risk limitation

Implementing controls to contain potential risk effects Risk transfer

Letting others assume risk (outsourcing)



3. Adjust project management approach Project management style

Authoritative vs. participatory Project budget and timeframe

Rigid vs. flexible Gibson’s Four Approaches

Big Bang Approach (all other 3 must be positive) Improvisation Guided evolution Top-down coordination


Gibson’s Four Approaches to Risk Management


Dow Corning

Case Example: Risk Management Successful ERP implementation (1995-

1999) How did it manage the different business risks?

Phase 0: Get Ready (assessed risks) Leadership (high) Employee perception (high) Scope and urgency (high)


Dow Corning cont’d

Phase 1: Understand the new system Used improvisation approach of participatory

management and flexible deadlines Emphasized building employee commitment

Phase 2: Redesign work processes Used guided evolution approach of participatory

management and fixed deadlines Achieving employee commitment did little to get work

processes redesigned Continued through the pilot (ERP cutover in new

European subsidiaries)


Dow Corning cont’d

Phase 3: Implement ERP worldwide Used top-down coordination with an authoritative

management style and flexible timelines Pilot’s success demonstrated managers’ resolve and

shifted employee perception to the positive “Company wide” scope created negative shift

Phase 4: Complete implementation Used the Big Bang approach of authoritative

management and firm deadlines ERP implemented in most sites by 1998, so all risk

factors turned positive


Fast Tips: Good IS Management

Establish the ground rules Foster discipline, planning, documentation and

management Obtain and document “final” user requirements Obtain tenders from all appropriate potential

vendors Include vendors in decision making Convert existing data Follow through after implementation


Modernizing Legacy Systems

BCG study: Replace or not? About 40% of replacement projects fail Seduction of “new toys” Upgrading is a better option

BCG three analyses (replace or not) Costs-benefits of system Fit between new system and business needs IS staff capabilities (Can they do the job?)


Options for Improving Legacy Systems

1. Restructuring the system Getting system ready for reengineering e.g., An application working fine but not running

efficiently needs restructuring 7 steps involved in the process


Restructuring the System


Options for Improving Legacy Systems cont’d

2. Reengineering the system (not BPR) Reverse Engineering

Extracting and converting data elements from existing systems and formats

Forward Engineering Moving them to new hardware platforms and creating

new applications



3. Refurbishing the system Add new extensions to a “good working” old

system Some examples of legacy system extensions

Supply input in a new manner Make new uses of input Allow programs to deal more comprehensively with

data Add a Web interface around a “blackbox”

e.g., FedEx’s package tracking system



4. Rejuvenate the system Adding new functions to a reengineered system

to make it more valuable Phases of rejuvenation process

1. Recognize a system’s potential

2. Clean up the system and make it more efficient

3. Establish a strategic role for the system Add new functionalities to create business value



5. Rearchitect the system Involves having an architecture for new systems,

and then using that design to upgrade legacy systems

CTOs now devising enterprise level IT architecture

How systems are interconnected One-system-at-a-time migration strategy



6. Replace with a package or service Replace a legacy system with a commercial

package Commercial packages have many options and

features that can be customized Replace with service delivered over the Internet

Quick availability Outsource IS responsibility to vendors Cost can be expensed (tax benefits)



7. Rewrite the system System is “too far gone” to rescue

Code convoluted and patched; technology antiquated

Alternative to replacement Rare (usually only for very specialized systems)


Measuring Systems Benefits

Measuring the value of information systems is an ongoing task for IS managers (justify) Constant evolution of technology

Top executives demand specific links between new systems and corporate financial measures (e.g., ROA, revenue) Is this reasonable?


Measuring Systems Benefits cont’d

Difficult task because IT itself is only one of many factors that contribute to successful use of systems

IT can trigger a series of events toward a goal, but those events are very much dependent on organizational context

Can you measure the value of decision support systems or data warehouses?

Can you calculate the ROI of e-commerce systems? Three suggestions to alleviate this conundrum

1. Distinguish between different roles of systems2. Measure what is important to management3. Assess investments across organizational levels


Distinguish Between the Different Roles of Systems

Information systems can play three roles1. Performance: “Support systems” to increase

efficiency

2. Business Value: Carry out a business strategy e.g., CAD system used to design products

3. Product or Service: Itself or as a basis for a product or service

e.g., Web-based information services


Measure what is important to management

1. Measuring organizational performance Meeting deadlines and milestones Operating within budget Quality (efficiency, costs)

e.g., time and costs reductions

2. Measuring business value Impact on value network (relationships)

Customers, partners, suppliers

3. Measuring a product or service Can be measured as a business venture (ROI)


Assess Investments Across Organizational Levels

Sources of value for IT at three levels Individual Division (or department) Corporation

Impact focus of an IT investment extends to Economic performance payoffs Organizational process payoffs Technology impacts (functionality)

Combine views to form 3 x 3 matrix


Do Investors Value IT Investments?

A study found that every $1 invested in computers yielded up to $17 in stock market value (and no less than $5) vis-à-vis $1 invested in property, plant and equipment (book value)

only yielded $1 in stock market value $1 investment in other assets (inventory, liquid assets, and

accounts receivables) yielded only $0.70

Researchers’ argument IT investment creates intangible asset value

Know-how, skills, organizational structures


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