Chapter 12 Systems Planning and Developement Flashcards
Planning Information Systems
- Enterprise ISs are gaining in popularity
- IS resource investment considerations
- Require a substantial investment
- Carry a high risk in implementation
- Successful integration of the system is vital
- Must align IT strategies with the overall organization strategies
- Careful planning of an IS implementation is necessary
IS resource investment considerations
- Require a substantial investment
- Carry a high risk in implementation
Steps in Planning Information Systems
Key steps in IT planning
- Create a corporate and IT mission statement
- Articulate the vision for IT within the organization
- Create IT strategic and tactical plans
- Create a plan for operations to achieve the mission and vision
- Create a budget to ensure that resources are available to achieve the mission and vision
- IT planning is similar to planning of other resource acquisitions
Steps associated w/ IS planning (example)
Coporate Mission IT Mission IT Vision IT Strategic Plan IT Tactical Plans Plans for Operations Budget
Mission statement
communicates the most important overarching goal of organization
-includes how the goal will be acheived
IT mission statement
describes the role of IT in the organization
- Should be compatible with the organizational mission statement
- Includes the ideal combination of hardware, software, and networking to support the mission
strategic plan for implementation of IT in the organization
developed by CIO
- addresses what technology will be used by employees, customers, and suppliers
Goals in strategic plan for implementation of IT in the organization
goals are broken down to objectives:
- Resources to be acquired or developed
- Timetables for acquiring and implementing resources
- Training
- Objectives are broken down to operational details
Growing proportion of IT funds is spent on software in recent years
- More purchasing and adapting of software
- Less developing in-house software
The Benefits of Standardization in Planning
- standardization
- Cost savings: better bargaining power in purchasing and leasing hardware and software
- Efficient training: a smaller variety of software reduces employee training needs
- Efficient support: enables more staff specialization
2 general approaches from planning to development
- Systems development life cycle (SDLC), the traditional approach
- Nontraditional methods, including agile methods
The two development approaches are not necessarily mutually exclusive
(same for in-house or purchased systems)
Prototyping
fast development of an application based on initial user requirements
Systems development may involve progressive elaboration…..why?
As more information and knowledge is available, a vision of an initiative continually develops and influences the final product
SDLC
systems development life cycle
Large ISs are conceived, planned, and developed within the framework
- Also known as “waterfall” development
Major sequential phases of SDLC
- Analysis
- Design
- Implementation
- Support
Systems analysis: a five-step process
- Investigation
- Small ad hoc team performs a preliminary investigation by interviewing employees
- Technical feasibility study
- determines if:
- Components exist or can be developed
- The organization has adequate hardware
- determines if:
- Economic feasibility study
- Cost/benefit analysis: spreadsheet showing all costs and benefits of the proposed system
- Return on investment (ROI): difference between the stream of benefits and the stream of costs over the life of the syste
- Operational feasibility study
- Software license fees, maintenance personnel, telecommunications, power, and computer-related supplies
- Total cost of ownership (TCO): a financial estimate for business leaders to objectively and accurately evaluate the direct and indirect costs of a new organizational project
- Organizational culture: general tone of the corporate environment
- Must determine the new system’s compatibility with the organizational culture
- Requirements definition
- System requirements: detail the functions and features expected from the new system
Feasibility studies
a larger analysis conducted after preliminary results indicate an IS is warranted
TCO
Total cost of ownership :
a financial estimate for business leaders to objectively and accurately evaluate the direct and indirect costs of a new organizational project
Organizational culture
general tone of the corporate environment
- Must determine the new system’s compatibility with the organizational culture
System requirements
detail the functions and features expected from the new system
Systems design
- Second phase in systems development
- Systems design: includes three steps for devising the means to meet all the requirements
- Description of the components
- Construction
- Testing
- If purchasing a system:
- Design phase determines how to adapt the existing software
- Construction: actual changes in program code
- Design phase determines how to adapt the existing software
- Symbols are used to communicate ideas about data, processes, and information
- Visual information can be grasped more quickly
3 steps in system design
1 description of components
2 construction
3 Testing
Data flow diagram (DFD)
describes the flow of data in a business operation using four symbols
- External entities: individuals and groups external to the system (customers, employees, etc.)
- Processes: an event or events that affect data
- Data store: any form of data at rest
- Direction of data flow: indicates how data moves
advantages of DFD
-symbols are suitable for describing any IS, including noncomputer-based ISs
- Can help pinpoint weaknesses:
- Where processes can be automated
- What is shared by different processes
- What can be changed to strengthen the IS
disadvantage of DFD
- cannot describe a system completely
- Does not depict computations within processes or timing relationships among data flows
Unified modeling language (UML)
de facto standard for visualizing, specifying, and documenting software
- Helps developers communicate and logically validate desired features
- Is independent of programming languages
- Provides standard symbols and notations for depicting object-oriented elements
UML diagrams
- Use case: an activity of the system in response to the user (an actor)
- Class: describes class structure and contents
- Interaction: describes interactions of objects and the sequence of their activities
- State charts: indicate the states through which objects pass and their responses to stimuli
- Activity: represents highly active states triggered by completion of other actions
- Physical diagrams: high-level descriptions of software modules
Design (construction)
- Consists of mostly programming activities
- May take months or years
- Each completed module is tested
- Modules are integrated
Design ( system testing )
- Tests the entire integrated system, comparing results to the system requirements
- Testing period often is the victim of schedule or budget compression, resulting in poor testing
Impementation
delivery of a new system
Steps include:
- Conversion
- Training
-Training may or may not precede conversion
Conversion
- switching from the old system to the new system
- Can be a very difficult time
Implementation Conversion Strategies
- Parallel conversion: the old system is used simultaneously with the new system at first
- Phased conversion: breaks the new IS into modules and integrates one at a time
- Reduces risk but delays some benefits
- Cut-over conversion (or flash cut conversion): immediately replaces all modules
- Risky but may be inexpensive
- Pilot conversion: introduces the IS into one business unit at a time
- Beta site: a site that tests the new system
Parallel conversion
the old system is used simultaneously with the new system at first
Phased conversion
breaks the new IS into modules and integrates one at a time
- Reduces risk but delays some benefits
Cut-over conversion (or flash cut conversion)
immediately replaces all modules
- Risky but may be inexpensive
Pilot conversion
introduces the IS into one business unit at a time
- Beta site: a site that tests the new system
Beta site
a site that tests the new system
Application systems support
includes two responsibilities
- Maintenance: post-implementation debugging, updates, and adding postponed features
- User help
- Maintenance comprises up to 80% of IS budgets
- Support is the longest phase of the system life cycle
- Effective maintenance requires good system documentation during development
Agile methods
alternative development methods
- Treat software development as series of contacts with users
- Goal: fast software development
- Improve software after user requests for modifications received
- Agile methods use iterative programming
- aim to have “light but sufficient” development processes
- User involvement is encouraged throughout the process
- Modules are tested immediately after completion
- Communication with users is informal
- XP uses two programmers per module working on the same computer
- Fosters constructive criticism and feedback
- DaimlerChrysler payroll system was a large XP project that failed
- British Airways provides an agile success story
Popular agile methods
- Extreme programming (XP)
- Adaptive software development (ASD)
- Lean development (LD)
- Rational unified process (RUP)
- Feature driven development (FDD)
- Dynamic systems development method (DSDM)
- Scrum
- Crystal Clear
Major advantage of agile methods
Fast development of application software
Some risks of agile methods
- Analysis phase is limited or eliminated, increasing the risk of incompatibilities
- More emphasis on programming, resulting in less documentation, which may make it difficult or impossible to make later modifications
Manifesto for Agile Software Development expresses these priorities:
- Individuals and interactions over processes
- Working software over comprehensive documentation
- Customer collaboration over contract negotiation
- Responding to change over following a plan
When to Use Agile Methods
When a desired system is small
- Analysis is less important
- Requires a smaller investment of resources
- For unstructured problems
- For developing user interfaces
- When users cannot specify all requirements at the start of the project
- They may be unfamiliar with the technology
- Requirements may be difficult to conceptualize
When Not to Use Agile Methods
- The desired system is large or complex
- System failure entails great financial loss
- The desired system must interface with other systems
- SDLC recommended for complex systems
- Documentation is key for integration
Outsourcing
the formal business relationship to transfer internal business processes and functions to a third-party business
- Outsourcing is steadily being used by organizations
- Maximize their value as well as reduce costs
- Many industries and businesses seek third-party outsourcing vendors to create efficiencies
- Not all outsourcing initiatives are successful
- UBS Global Asset Management attempt (2010)
Project Planning and Management Tools
- Several tools exist to help plan and manage a development project, including IS projects
- IBM’s Rational Portfolio Manager
Helps plan investment in a new system and manage the development project and delivery - Oracle’s Primavera 6
Provides integrated project portfolio management (PPM) software
- IBM’s Rational Portfolio Manager
- Tools designed to accommodate planning and management of any type of project
- Clarizen
- Project Insight
- AtTask
- Microsoft Projec
Systems integration
- Examines the needs of entire organization
- Produces a plan to combine disparate systems to allow data to flow between units
- Some service companies specialize in systems integration
- Integration is more challenging than development
- Legacy systems may need to be interfaced with new systems
- Systems integrators must be skilled in hardware and software
- May be difficult to overcome hardware and software incompatibility issues between systems
- Systems integration may span several organizations, requiring integration using telecommunications
Summary
- IT planning is important because of high investment costs and high risk in implementing enterprise applications
- Standardization is an important part of IT planning
- Systems development life cycle (SDLC) has well-defined phases: analysis, design, implementation, and support
- Purpose of systems analysis is to determine what needs the system will satisfy
- Feasibility studies determine if a proposed system is possible and desirable
- System requirements detail the features needed
- Developers outline system components graphically and construct the software
- Models of the desired system are created using tools, e.g., data flow diagrams and Unified Modeling Language (UML)
- Implementation includes training and conversion from the old system to the new system
- Support entails maintenance and satisfying changing needs
- Agile methods are a popular alternative to traditional systems development life cycle
- Tools help plan and manage development projects
- Systems integration may be more complicated than systems development
- Great responsibility of IS professionals results in the desirability of certification
