chapter 11 11-1 chapter eleven overview section 11.1 – developing enterprise applications...
TRANSCRIPT
Chapter 11
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CHAPTER ELEVEN OVERVIEW
SECTION 11.1 – DEVELOPING ENTERPRISE APPLICATIONS
• Developing Software• The Systems Development Life Cycle• Traditional Software Development Methodology: Waterfall• Agile Software Development Methodologies• Developing Successful Software SECTION 11.2 – PROJECT MANAGEMENT• Managing Software Development Projects• Project Management Fundamentals• Choosing Strategic Projects• Understanding Project Planning• Managing Projects, Resources, and Change• Outsourcing Projects
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DEVELOPING SOFTWARE
• As organizations’ reliance on software grows, so do the business-related consequences of software successes and failures including: Increase or decrease revenue Repair or damage to brand reputation Prevent or incur liabilities Increase or decrease productivity
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INTRODUCTION
• When developing a new system, you have 3 “who” choices…1. Insourcing – IT specialists inside your
organization2. Selfsourcing – do-it-yourself approach
many end users take with little or no help from IT specialists
3. Outsourcing – a third-party organization (i.e., let someone do the work and pay them for it)
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INSOURCING AND THE SDLC
• Systems development life cycle (SDLC) - a structured step-by-step approach for developing information systems
• 7 distinct phases, each with well-defined activities
• Also called a waterfall methodology, an approach in which each phase of the SDLC is followed by another, from planning through implementation
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SDLC Phases & Major Activities
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SDLC as a Waterfall Methodology
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Phase 1: Planning
• Planning phase - create a solid plan for developing your information system
• Three primary planning activities:1. Define the system to be developed
o You can’t build every system, so you make choices based on your organization’s priorities, which may be expressed as critical success factors
o Critical success factor (CSF) - a factor simply critical to your organization’s success
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Phase 1: Planning
2. Set the project scopeo Project scope - clearly defines the high-
level system requirements o Scope creep - occurs when the scope of the
project increaseso Feature creep - occurs when developers
add extra features that were not part of the initial requirements
o Project scope document - a written definition of the project scope and is usually no longer than a paragraph
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Phase 1: Planning
3. Develop the project plan including tasks, resources, and timeframeso Project plan - defines the what, when, and
who questions of system developmento Project manager - an individual who is an
expert in project planning and management, defines and develops the project plan and tracks the plan to ensure all key project milestones are completed on time
o Project milestones - represent key dates for which you need a certain group of activities performed
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Phase 1: Planning (Gantt chart)Can use MS-Project to create them)
Sample Project Plan
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Phase 2: Analysis
• Analysis phase - involves end users and IT specialists working together to gather, understand, and document the business requirements for the proposed system
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Phase 2: Analysis
• Two primary analysis activities:1. Gather the business requirements
o Business requirements - the detailed set of knowledge worker requests that the system must meet in order to be successful
o Business requirements address the “why” and “what” of your development activities
o Joint application development (JAD) - knowledge workers and IT specialists meet, sometimes for several days, to define or review the business requirements for the system
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Phase 2: Analysis
2. Prioritize the requirementso Requirements definition document –
prioritizes the business requirements and places them in a formal comprehensive document
o Again, you probably can’t do everything, so prioritizing is important
o Users sign off on this document which clearly sets the scope for the project
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Phase 2: Analysis
Take time during analysis to get the business requirements correct. If you find errors, fix them immediately. The cost to fix an error in the early stages of the SDLC is relatively small. In later stages, the cost is huge.
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Phase 3: Design
• Design phase - build a technical blueprint of how the proposed system will work
• Two primary design activities:1. Design the technical architecture
o Technical architecture - defines the hardware, software, and telecommunications equipment required to run the system
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Phase 3: Design
2. Design system modelso This includes GUI screens that users will
interface with, database designs (see XLM/C), report formats, software steps, etc
• Starting with design, you take on less of an active participation role and act more as a “quality control” function, ensuring that the IT people are designing a system to meet your needs
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Phase 4: Development
• Development phase - take all of your detailed design documents from the design phase and transform them into an actual system
• Two primary development activities:1. Build the technical architecture2. Build the database and programs
o Both of these activities are mostly performed by IT specialists
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Phase 5: Testing
• Testing phase - verifies that the system works and meets all of the business requirements defined in the analysis phase
• Two primary testing activities:1. Write the test conditions
o Test conditions - the detailed steps the system must perform along with the expected results of each step
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Phase 5: Testing
2. Perform the testing of the systemo Unit testing – tests individual units of codeo System testing – verifies that the units of
code function correctly when integratedo Integration testing – verifies that separate
systems work togethero User acceptance testing (UAT) –
determines if the system satisfies the business requirements
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Phase 6: Implementation
• Implementation phase - distribute the system to all of the knowledge workers and they begin using the system to perform their everyday jobs
• Two primary implementation activities1. Write detailed user documentation
o User documentation - highlights how to use the system
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Phase 6: Implementation
2. Provide training for the system userso Online training - runs over the Internet or
off a CD-ROM o Workshop training - is held in a classroom
environment and lead by an instructor
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Phase 6: Implementation
• Choose the right implementation method Parallel implementation – use both the
old and new system simultaneously Plunge implementation – discard the old
system completely and use the new Pilot implementation – start with small
groups of people on the new system and gradually add more users
Phased implementation – implement the new system in phases
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Phase 7: Maintenance
• Maintenance phase - monitor and support the new system to ensure it continues to meet the business goals
• Two primary maintenance activities:1. Build a help desk to support the system
users o Help desk - a group of people who responds
to knowledge workers’ questions
2. Provide an environment to support system changes
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COMPONENT-BASED DEVELOPMENT
• The SDLC focuses only on the project at hand• Component-based development (CBD) –
focuses on building small self-contained blocks of code (components) that can be reused across a variety of applications
• CBD focuses on1. Using already-developed components to build
systems quickly2. Building new components as needed that can
be used in all future systems
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Component-Based Development Methodologies
• Rapid application development (RAD)• Extreme programming (XP)• Agile methodology
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Rapid Application Development (RAD)
• Rapid application development (RAD) (also called rapid prototyping) - emphasizes extensive user involvement in the rapid and evolutionary construction of working prototypes of a system to accelerate the systems development process
• Prototypes are models of the software components• The development team continually designs,
develops, and tests the component prototypes until they are finished
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Agile Methodology
• Agile methodology - a form of XP, aims for customer satisfaction through early and continuous delivery of useful software components
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SoA – An Architecture Perspective
• Service-oriented architecture (SoA) – perspective that focuses on the development, use, and reuse of small self-contained blocks of code (called services) to meet all application software needs
• All CBD methodologies adhere to an SoA• Services are the same as components,
which are the same as small self-contained blocks of code
• More in Chapter 7
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SELFSOURCING
• Selfsourcing (end-user development) – the development and support of IT systems by end users with little or no help from IT specialists
• Do-it-yourself systems development approach
• Can relieve IT specialists of the burden of developing many smaller systems
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Selfsourcing Approach
• Is similar to traditional SDLC• Big exception is that design, development, testing, and implementation are replaced by the process of prototyping
• Prototyping is the process of building models, and – in this case – continually refining those models until they become the final system
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Selfsourcing Approach
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Selfsourcing Advantages
• Improves requirements determination• Increases end user participation and sense of
ownership• Increases speed of systems development• Reduces invisible backlog
Invisible backlog – list of all systems that an organization needs to develop but – because of the prioritization of systems development needs – never get funded because of the lack of organizational resources
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Selfsourcing Disadvantages
• Inadequate end user expertise leads to inadequately developed systems
• Lack of organizational focus creates “privatized” IT systems
• Insufficient analysis of design alternatives leads to subpar IT systems
• Lack of documentation and external support leads to short-lived systems
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The Right Tool for the Job
• End users must have development tools that: Are easy to use Support multiple platforms Offer low cost of ownership Support a wide range of data types
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PROTOTYPING
• Prototype – a model of a proposed product, service, or system
• Prototyping - the process of building a model that demonstrates the features of a proposed product, service, or system Proof-of-concept prototype - used to
prove the technical feasibility of a proposed system
Selling prototype - used to convince people of the worth of a proposed system
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The Prototyping Process
• The prototyping process involves four steps:1. Identify basic requirements2. Develop initial prototype3. User review4. Revise and enhance the prototype
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Advantages of Prototyping
• Encourages active user participation • Helps resolve discrepancies among users• Gives users a feel for the final system• Helps determine technical feasibility • Helps sell the idea of a proposed system
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Disadvantages of Prototyping
• Leads people to believe the final system will follow
• Gives no indication of performance under operational conditions
• Leads the project team to forgo proper testing and documentation
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OUTSOURCING
• Outsourcing – the delegation of specified work to a third party for a specified length of time, at a specified cost, and at a specified level of service
• The third “who” option of systems development, after insourcing and selfsourcing
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OUTSOURCING
• The main reasons behind the rapid growth of the outsourcing industry include the following: Globalization The Internet Growing economy and low unemployment
rate Technology Deregulation
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Outsourcing Options
• IT outsourcing for software development can take one of four forms:1. Purchase existing software2. Purchase existing software and pay the
publisher to make certain modifications3. Purchase existing software and pay the
publisher for the right to make modifications yourself
4. Outsource the development of an entirely new and unique system for which no software exists
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Outsourcing Process
• Like selfsourcing, the selfsourcing process looks similar to the traditional SDLC
• Big exception here is that you “outsource” most of the work to another company
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Outsourcing Options
• There are three different forms of outsourcing:1. Onshore outsourcing - the process of
engaging another company within the same country for services
2. Nearshore outsourcing - contracting an outsourcing arrangement with a company in a nearby country
3. Offshore outsourcing - contracting with a company that is geographically far away
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Offshore Outsourcing
• Primary outsourcing countries are: India China Eastern Europe (including Russia) Ireland Israel Philippines
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The Advantages and Disadvantages of Outsourcing
• Advantages: Focus on unique core competencies Exploit the intellect of another organization Better predict future costs Acquire leading-edge technology Reduce costs Improve performance accountability
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The Advantages and Disadvantages of Outsourcing
• Disadvantages: Reduces technical know-how for future
innovation Reduces degree of control Increases vulnerability of your strategic
information Increases dependency on other
organizations
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THE SYSTEMS DEVELOPMENT LIFE CYCLE
• Systems development life cycle (SDLC) – the overall process for developing information systems from planning and analysis through implementation and maintenance
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WATERFALL METHODOLOGY
• Waterfall methodology – an activity-based process in which each phase in the SDLC is performed sequentially from planning through implementation and maintenance
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AGILE METHODOLOGY
• Agile methodology – aims for customer satisfaction through early and continuous delivery of components developed by an iterative process
Rapid application development methodology (RAD)
Extreme programming (XP) methodology
Rational Unified Process (RUP) SCRUM
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DEVELOPING SUCCESSFUL SOFTWARE
• Primary principles for successful agile software development include:
Slash the budget If it doesn’t work, kill it Keep requirements to a minimum Test and deliver frequently Assign non-IT executives to software
projects
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THE TRIPLE CONSTRAINT
• Project management interdependent variables
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PROJECT MANAGEMENT FUNDAMENTALS
• Project management role
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CHOOSING STRATEGIC PROJECTS
• Three common techniques for selecting projects
1. Focus on organizational goals2. Categorize projects3. Perform a financial analysis
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UNDERSTANDING PROJECT PLANNING
• Building a project plan involves two key components: Project charter - a document issued by
the project initiator or sponsor that formally authorizes the existence of a project and provides the project manager with the authority to apply organizational resources to project activities
Project plan – a formal, approved document that manages and controls project execution
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PROJECT PLAN
• Two primary diagrams used in project planning include PERT and Gantt charts
PERT chart – a graphical network model that depicts a project’s tasks and the relationships between those tasks
o Dependencyo Critical path
Gantt chart – a simple bar chart that depicts project tasks against a calendar
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MANAGING PROJECTS
• Managing a project includes: Identifying requirements Establishing clear and achievable objectives. Balancing the competing demands of quality,
scope, time, and cost Adapting the specifications, plans, and
approach to the different concerns and expectations of the various stakeholders
• Primary areas of focus: Managing people; Managing communications;
Managing change
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OUTSOURCING PROJECTS
• Reasons companies outsource
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OUTSOURCING PROJECTS
• Outsourcing benefits include: Increased quality and
efficiency Reduced operating expenses, Outsourcing non-core
processes Reduced exposure to risk Economies of scale, expertise,
and best practices Access to advanced
technologies Increased flexibility Avoid costly outlay of capital
funds Reduced headcount and
associated overhead expense Reduced time to market for
products or services
• Outsourcing challenges Contract length Competitive edge Confidentiality Scope definition