CHAPTER 7 Flashcards
is a model of software deployment where an application is hosted as a service provided to customers over the Internet. SaaS reduces the customer’s need for software maintenance, operation, and support.
Software as a Service
describe a second generation of the Web that will enable people to collaborate, interact, and share information much more effectively.
Web 2.0
refers to the cloud symbol that indicates a network, or the Internet.
cloud computing
is the transfer of information systems development, operation, or maintenance to an outside firm that provides these services, for a fee, on a temporary or long-term basis.
Outsourcing
firm that offers outsourcing solutions
service provider
Two popular outsourcing options
APPLICATION SERVICE PROVIDERS & INTERNET BUSINESS SERVICES
application service provider (ASP) is a firm that delivers a software application, or access to an application, by charging a usage or subscription fee.
APPLICATION SERVICE PROVIDERS
provide powerful Web-based support for transactions such as order processing, billing, and customer relationship management.
INTERNET BUSINESS SERVICES
Outsourcing Fees involves…
fixed fee model, subscription model & usage model or transaction model
uses a set fee based on a specified level of service and user support.
fixed fee model
has a variable fee based on the number of users or workstations that have access to the application.
subscription model
charges a variable fee based on the volume of transactions or operations performed by the application.
usage model or transaction model
refers to the practice of shifting IT development, support, and operations to other countries.
Offshore outsourcing, or global outsourcing
choice between developing versus purchasing software often
make or buy, or build or buy decision.
Companies that develop software for sale
software vendors.
firm that enhances a commercial package by adding custom features and configuring it for a particular industry
value-added reseller (VAR)
software package that can be used by many different types of organizations
horizontal application
software package developed to handle information requirements for a specific type of business
vertical application
Developing Software In-House
SATISFY UNIQUE BUSINESS REQUIREMENTS
MINIMIZE CHANGES IN BUSINESS PROCEDURES AND POLICIES
MEET CONSTRAINTS OF EXISTING SYSTEMS
MEET CONSTRAINTS OF EXISTING TECHNOLOGY
DEVELOP INTERNAL RESOURCES AND CAPABILITIES
Purchasing a Software Package
LOWER COSTS
REQUIRES LESS TIME TO IMPLEMENT
PROVEN RELIABILITY AND PERFORMANCE BENCHMARKS
REQUIRES LESS TECHNICAL DEVELOPMENT STAFF
FUTURE UPGRADES PROVIDED BY THE VENDOR
INPUT FROM OTHER COMPANIES
utilizes standard business software, such as Microsoft Word or Microsoft Excel
user application
responsible for providing user support
help desk, or information center (IC)
Financial Analysis Tools
Payback analysis
Return on investment (ROI)
net present value (NPV)
determines how long it takes an information system to pay for itself through reduced costs and increased benefits.
Payback analysis
percentage rate that compares the total net benefits (the return) received from a project to the total costs (the investment) of the project.
Return on investment (ROI)
total value of the benefits minus the total value of the costs, with both costs and benefits adjusted to reflect the point in time at which they occur.
net present value (NPV)
contains the requirements for the new system, describes the alternatives that were considered, and makes a specific recommendation to management.
system requirements document, or software requirements specification
defines what must take place, not how it will be accomplished.
logical design
set of blueprints for the actual construction of a building.
Physical design
build a system that satisfies business requirements. A successful system must be effective, reliable, and maintainable
systems design
Design considerations usually involves:
USER CONSIDERATIONS
DATA CONSIDERATIONS
ARCHITECTURE CONSIDERATIONS
USER CONSIDERATIONS
Carefully consider any point where users receive output or provide input.
Anticipate future needs.
Provide flexibility.
DATA CONSIDERATIONS
Enter data as soon as possible.
Verify data as it is entered.
Use automated methods of data entry whenever possible.
Control data entry access and report all entries or changes to critical values
Log every instance of data entry and changes.
Enter data once.
Avoid data duplication.
ARCHITECTURE CONSIDERATIONS
Use a modular design.
Design modules that perform a single function.
produces an early, rapidly constructed working version of the proposed information system
Prototyping
working version of the proposed information system
prototype
commands tend to resemble natural statements that people use
fourth-generation language (4GL)
the tools provide a framework for rapid, efficient software development
fourth-generation environment.
architectural style whose goal is to achieve loose coupling among interacting software objects that provide services.
Service-oriented architecture (SOA)
objects can interact, but are essentially independent.
Loose coupling