it architecture © holmes miller 1999. building metaphor 3customer’s concern has vision about...
Post on 19-Dec-2015
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BUILDING METAPHOR
CUSTOMER’S CONCERN Has vision about building that will meet
needs and desiresARCHITECT’S CONCERN Translates the vision into a plan to construct
the building
ANALOGOUS TO A BUILDING
GENERAL MANAGER’S CONCERN Applications to use, data that will be accessible,
and communications that will be possibleIT ARCHITECT’S CONCERN Desired system functions and appropriate
technology
HARDWARE COMPONENTS
Central processing unitPrimary storageSecondary storageInput devicesOutput devicesTelecommunications links
DATABASE ORGANIZATION
SEQUENTIAL ORGANIZATION Tape oriented - one file follows
anotherDIRECT ORGANIZATION Disk oriented - can be accessed
without regard to physical sequence
DATABASE MANAGEMENT SYSTEMS
STORED IN WAY FOR DIFFERENT BUSINESSES TO ACCESS THE SAME DATA
COMPONENTSData definition languageDatabase management softwareData dictionary
DATABASE PROS & CONS
HIERARCHIAL High efficiency - Low flexibilityNETWORK Medium efficiency - Medium flexibilityRELATIONAL Low efficiency - High flexibility
DATABASE TRENDS
DISTRIBUTED PROCESSING Multiple systems connected via a network DISTRIBUTED DATABASE Data physically stored in more than one location DATA WAREHOUSE Consolidate current & historical information --
Data Mining!
DATABASE TRENDSDATA WAREHOUSE: Organization’s
electronic library stores consolidated current & historic data for management reporting & analysis
DATA MART: Small data warehouse for special function, e.G., Focused marketing based on customer info
COMPONENTS OF DATA WAREHOUSE
INFORMATIONDIRECTORY
INTERNALDATASOURCES
EXTERNALDATASOURCES
OPERATIONAL,HISTORICAL DATA
DATA WAREHOUSE
EXTRACT,TRANSFORM
DATAACCESS &ANALYSIS
QUERIES &REPORTS
OLAP
DATA MINING
DATABASE TRENDS
ON-LINE ANALYTICAL PROCESSING (OLAP): ability to manipulate, analyze large volumes of data from multiple perspectives
LINKING DATABASES TO THE WEB
ELEMENTS OF DATABASE ENVIRONMENT
DATABASE MANAGEMENT
SYSTEM
DATA
ADMINISTRATION DATABASETECHNOLOGY & MANAGEMENT
USERS
DATA PLANNING & MODELING
METHODOLOGY
COMMUNICATIONS LINKS
NETWORKS Hardware and software that permits
computer-computer or computer-peripheral communication
COMMUNICATIONS DEVICES Hardware devices to control communication
in a computer system
DEVELOPING AN ARCHITECTURE
SOME ISSUESOn-going business processCentral vs. local controlStandardsVendorsRules & policies
DEVELOPING AN ARCHITECTURE
OVERALL PROCEDUREWhere are we now?Where do we want to be?How should we get there?TWO APPROACHESEvolutionaryRevolutionary
DEVELOPING AN ARCHITECTURE
FIVE STEPSArticulate the business strategy and architecture
implicationsBaseline the company architectureDetermine key architecture questionsDesign the blueprintInitiate the architecture plan
CAPITAL BUDGETING MODELSLIMITATIONS: Assume all relevant alternatives
have been examined; cost & benefits can be expressed as $$
Ignore intangible benefits
UNDERSTANDING BUSINESS VALUE OF INFO SYSTEMS
Capital Budget:
Process of analyzing, selecting capital expenditures
Payback method Return on investment Cost-benefit ratio Net present value Profitability index Internal rate of return
Tangible benefit: Increased productivity Low operating costs Reduced work force Lower computer expenses Lower vendor costs Lower clerical/professional costs Reduced growth of expenses Reduced facility costs
Costs & Benefits:
Intangible benefit: Improved asset use; resource control; planning Increased flexibility More timely information Increased learning Attain legal requirements Enhanced employee goodwill, job satisfaction,
decision making, operations Higher client satisfaction Better corporate image
Costs & Benefits: