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© Gabriele Piccoli
Creating Information Systems
What managers need to know about the process by which organizational information systems come to be
© Gabriele Piccoli
Course Roadmap
• Part I: Foundations• Part II: Competing in the Internet Age• Part III: The Strategic use of Information Systems• Part IV: Getting IT Done
– Chapter 10: Funding Information Systems– Chapter 11: Creating Information Systems– Chapter 12: Information System Trends– Chapter 13: Security, Privacy and Ethics
© Gabriele Piccoli
Learning Objectives
1. Come to appreciate how complex it is to design and implement organizational information systems and the stable, robust, secure technology at their core
2. Articulate the advantages and disadvantages of custom software design and development versus acquisition of an off-the-shelf product
3. Describe and be able to use the main methodologies for custom software design and development. Specifically: the system development life cycle (SDLC) and the prototyping approach
4. Describe the systems selection methodology and be able to use it to choose a prepackaged software program for a specific organization
5. Describe why end-user development is increasingly prominent in modern organizations. Articulate its benefits and risks
© Gabriele Piccoli
How Hard can IT be?
© Gabriele Piccoli
Information Systems Development
• Technology Development– The process of creating the core IT– IT can be acquired and integrated into
existing infrastructure– IT can be custom-built by (or for) the
organization• Information System Development
– Successfully integrating the technology with the other components to achieve a working system
© Gabriele Piccoli
Three Approaches
1. Custom design and development• Implementing software that is expressly made
to fit the unique needs of the organization2. System selection and acquisition
• Implement an off-the-shelf application that is mass produced by a vendor
3. End-user development• Implement a software application that is
created by an end users, rather than the firms IS professionals
© Gabriele Piccoli
Advantages of Custom Development
• Unique Tailoring– Molded to fit the unique features,
characteristics, and needs of the firm that commissions them.
– Off-the-shelf software may require adjustment (customization) to fit the organization
• Flexibility and Control– Building from scratch allows the software to
be molded into any form and modified at a later time
© Gabriele Piccoli
Advantages of Purchasing• Faster Roll-Out
– Purchased software dramatically reduce the time it takes to obtain the software and to begin the implementation process
• Knowledge Infusion– Software developers proactively seek out best
practices in order to code their applications• Economically Attractive
– The firm can capitalize on economies of scale created by the vendor
• Software Quality: Mature off-the-shelf products have been heavily tested
© Gabriele Piccoli
Make and Buy
• Modern firms are blending the custom development and selection approaches– First firms acquire off-the-shelf systems, then
they modify them extensively– Few firms modify off-the-shelf applications
slightly or not at all– Off-the-shelf applications are becoming larger
and more complex, and require some modification to fit the purchasing firm
© Gabriele Piccoli
Design and Development Methodologies
© Gabriele Piccoli
Systems Development Life Cycle
• The SDLC approach is predicated on the notion that detailed justification and planning will reduce risk and uncertainty in systems development– Critical: Involvement from end-users and
functional managers– Requires considerable time analyzing
requirements up front– Requires that changes after the project has
started be kept to a minimum
© Gabriele Piccoli
Principal Phases of the SDLC
• Definition– Investigation– Feasibility Analysis– System Analysis
• Build– System Design– Programming– Testing
• Implementation– Installation– Operations– Maintenance
© Gabriele Piccoli
SDLC: Definition Phase
• Concerned with clearly identifying the features of the proposed information system
• Critical is the involvement of end-users and functional managers at this time
• Systems Analysts:– Identify and articulate the system
requirements– Act as liaisons with the technical staff
© Gabriele Piccoli
SDLC: Definition Phase
• Investigation– Identify the business issues the system will
pertain to– Formulate:
• Main goals of the system• Scope of the design• Value proposition of the new system
– Typically a very informal stage
© Gabriele Piccoli
SDLC: Definition Phase
• Feasibility Analysis– Used to ensure that organizational resources are put
to the best use– Technical Feasibility: Evaluate whether the
proposed system is viable from a technology standpoint
– Operational Feasibility: Evaluate whether the Information System as planned will work in the organization
– Economic Feasibility: Evaluation of the financial viability of the system
• Perform a cost/benefit analysis in order to ensure the money spent will meet the firm’s financial hurdles.
© Gabriele Piccoli
SDLC: Definition Phase
• Systems Analysis– The process of identifying and articulating the system
requirements– Systems analysts play a major role at this stage– Systems analysts must seek out and value the input of
end-users and other stakeholders– The systems requirements document
• Details the inputs the systems will accept • Details the outputs the system will produce• Once approved (client sign-off), the requirements are “frozen” • In a strict waterfall approach no further changes are allowed
© Gabriele Piccoli
Principal Phases of the SDLC
• Definition– Investigation– Feasibility Analysis– System Analysis
• Build– System Design– Programming– Testing
• Implementation– Installation– Operations– Maintenance
© Gabriele Piccoli
SDLC: Build Phase
• Take system requirements document and produce a:– Robust– Secure– Efficient application
• Systems Design– Using the results from the definition phase, systems
architects create the overall structure of the system– The output of this stage is a precise set of documents
that programmers will employ to write code
© Gabriele Piccoli
System Design: Example
© Gabriele Piccoli
SDLC: Build Phase
• Programming– The process of translating the abstract
software design into a set of instructions that can be executed by the hardware
– Thorough and clear documentation is essential for
– Support– Maintenance– Upgrades
© Gabriele Piccoli
SDLC: Build Phase
• Testing– Programmers are constantly engaged in
testing as they develop the system– Formalized testing of the completed
application is an essential stage of the SDLC– The objective it to release the application
when it is good enough, not when it is flawless
© Gabriele Piccoli
Principal Phases of the SDLC
• Definition– Investigation– Feasibility Analysis– System Analysis
• Build– System Design– Programming– Testing
• Implementation– Installation– Operations– Maintenance
© Gabriele Piccoli
SDLC: Implementation Phase
• The process of ensuring that the technology is properly integrated with the other components of the information system
• Extremely delicate time• Success at this stage requires:
– Project management skills – Executive involvement
© Gabriele Piccoli
SDLC: Implementation Phase
• Installation– The software is loaded on the production
hardware and the databases are populated– Typically occurs during slow periods for the
organization– Four ,major approaches:
1. Parallel 3. Phased
2. Direct 4. Pilot
© Gabriele Piccoli
SDLC: Implementation Phase
• Parallel Installation– Old and new systems are run for a time
together, in parallel• Offers insurance against failure of new application• Most costly as it requires redundancy of efforts
Old System
New System
© Gabriele Piccoli
SDLC: Implementation Phase
• Direct (Cutover) Installation– The old system is discontinued and the firm
cuts over to the new one.– Most radical approach– Unavoidable in some cases (e.g., Y2K)
Old System
New System
© Gabriele Piccoli
SDLC: Implementation Phase
• Phased Installation– The new system progressively replaces the
functionalities of the old one– Best suited for componentized or modular
applications that can be rolled out in stages
New SystemOld System
© Gabriele Piccoli
SDLC: Implementation Phase
• Pilot Implementation– Allows the firm to run the new system in one
business unit or one of the firm’s departments before rolling it out completely
– Well suited for multi-unit operations
Old System New System
© Gabriele Piccoli
SDLC: Implementation Phase
• End-user training– Occurs during the installation phase– Typically occurs in formal settings, such as
classrooms or make-shift computer labs• Change Management
– Process of smoothing the transition from the old system to the new work practices
– User resistance and inertia are the biggest dangers
© Gabriele Piccoli
SDLC: Implementation Phase
• Operations– At this stage the system is up and running and the
firm begins to use it– The system becomes a permanent asset of the
organization• Maintenance
– The process of:• Compiling errors requests• Prioritizing them• Implementing fixes and improvements
– Functionality gaps may arise and can be closed by way of upgrades and additions
© Gabriele Piccoli
Advantages of SLDC Approach
• Provides a systematic approach to software development
• Identifies roles and expectations of team members
• Best-suited for large-scale projects• Designed for cost control• Enforces a means of communication
between the project team and the project stakeholders
© Gabriele Piccoli
Prototyping
• Rooted in the notion that it is impossible to clearly estimate and plan complex information systems projects
• Allows for flexibility and iteration in the design process
• Enabled by tools that speed up the development process
• Can be used internally within the SDLC as a way to seek input user input
© Gabriele Piccoli
Prototyping Life Cycle
• Can be used as an alternative to the SDLC to develop a complete system:
1. Requirement Definitions2. Initial Prototype3. Evaluation4. Revision5. Completion
© Gabriele Piccoli
Prototyping Life Cycle
• Requirements Definitions– Process of determining basic requirements– Degree of precision is less than with SDLC
because requirements are not frozen• Initial Prototype
– The first iteration of the software– At this point, the software can take many
forms and can evolve in many directions
© Gabriele Piccoli
Prototyping Life Cycle
• Evaluation– Stakeholders review the prototype and provide
feedback on the current design– Offer requests for enhancements and new
functionality• Revision
– Design and coding of the requested changes– New prototype is developed and is submitted
for review
© Gabriele Piccoli
Prototyping Life Cycle
• Completion– Occurs after multiple iterations– The iterative evaluation and revision cycle
stops– The development team finalizes the system– Documentation and testing occur prior to the
formal release of the software
© Gabriele Piccoli
Advantages of the Prototyping Approach
• Speed• Closer to the users expectations:
– The process require more user involvement – Multiple iterations structure user feedback
• Enables the firm to experiment with new technologies
• Best suited to smaller-scale projects
© Gabriele Piccoli
Limitations to the Prototyping Approach
• The software is more likely to be lacking from a:– Security– Robustness– Reliability
• Often less thoroughly tested and documented
• May lead to unreasonable expectations • May lead to scope creep
© Gabriele Piccoli
Outsourced Development
• Custom-designed software programs are increasingly outsourced
• Virtual Development Teams– Teams that work together but are not
physically located together• Superior cost/quality ratio
– Superior quality products at a fraction of the cost of internal development
© Gabriele Piccoli
System Selection
• The process of:– Identifying – Purchasing – Implementingsuitable off-the-shelf software programs
• Typically spearheaded by management interest
© Gabriele Piccoli
Definition Phase
• Investigation– Identify the business issues the system will be
designed to address– Formulate goals and the scope of design
• Feasibility Analysis– Technical Feasibility: Evaluate whether the
proposed system is viable from a technology standpoint
– Operational Feasibility: Evaluate whether the Information System as planned will work in the organization
– Economic Feasibility: Evaluation of the financial viability of the system
© Gabriele Piccoli
Definition Phase
• Systems Analysis– Focus on determining the specific
functionalities required of the proposed system
• Formulate Evaluation Criteria– Essential features:
• Capabilities the system must have– Value adding features:
• Capabilities that offer significant advantages for which the firm will pay a premium
© Gabriele Piccoli
Definition Phase
• Compile Short List of Vendors– Identify potential vendors that meet the
Request For Proposal (RFP) requirements• Compile and Distribute the RFP
– RFP identifies critical system requirements and expectations
– Interested firms will respond to the RFP– An internal selection committee is formed
© Gabriele Piccoli
Definition Phase
• Evaluate Alternatives– The firm assesses competing solutions using the
criteria developed earlier– Compile list of top vendors
• Negotiate Contract– Object is to draft and sign a contract that provides the
needed solution and insulates the firm from future risk– Common components
• Cost,• Eventual liabilities• Control of intellectual property
© Gabriele Piccoli
Build Phase
• Configuration– The process of modifying through parameters– If necessary
• Customization– The process of modifying the application by designing
new functionality– Follows the system design and development
approach– Necessary to accommodate specific needs of the
organization• Testing for system performance
© Gabriele Piccoli
Implementation Phase
• Similar to SDLC implementation phase• Process change requirements are typically
greater for off-the-shelf applications than custom software
• Users are trained to operate the software• Change management may be substantial• The organization should plan to invest
considerable resources
© Gabriele Piccoli
End-User Development
• An umbrella term capturing the many ways in which knowledge workers, not IT professionals, create software
• Examples:– Spreadsheet models (written in MS Excel)– Personal databases (MS Access)– Software programs built with user-friendly
computer languages (Visual Basic for Application)
© Gabriele Piccoli
The Benefits of End-User Development
• Increased Speed of Development– Projects can be completed independently by
the end-user• End-user Satisfaction
– When a user creates their own applications, they are more likely to be satisfied with the result
• Reduced Pressure on the IS Function
© Gabriele Piccoli
The Risks of End-user Development
• Unreliable Quality Standards– Because of the limited skill set and knowledge of most
end users, the quality of their work varies dramatically• High Incidence of Errors
– The focus on outcomes and rapid development increase the likelihood of errors
• Continuity Risks– Often difficult for anyone but the individual who wrote
the program to understand it, enhance it, or support it
© Gabriele Piccoli
What we Learned
1. Come to appreciate how complex it is to design and implement organizational information systems and the stable, robust, secure technology at their core
2. Articulate the advantages and disadvantages of custom software design and development versus acquisition of an off-the-shelf product
3. Describe and be able to use the main methodologies for custom software design and development. Specifically: the system development life cycle (SDLC) and the prototyping approach
4. Describe the systems selection methodology and be able to use it to choose a prepackaged software program for a specific organization
5. Describe why end-user development is increasingly prominent in modern organizations. Articulate its benefits and risks