Transcript Operating Systems and Application Software.ppt

BA471
Management
Information Systems
Operating Systems and
Application Software
Operating Systems
 What do Operating Systems do?
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Perform hardware functions
Manage I/O
Use and monitor memory
Initiate, terminate, monitor processing
Provide network functions
Control access
Manage files
Operating Systems - analogy
“Tessekkuler”
means “Thank
you.”
TRAFFIC
COP
TRANSLATOR
NIGHT
WATCHMAN
Operating System
 Who’s on first?
Application Software
Operating
System
ALU
CONTROL
UNIT
REGISTER
MEMORY
Operating Systems
 Famous Operating Systems
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MVS (OS/390)
Unix (AIX, Solaris)
Linux
Windows
Mac OS
Operating Systems
 Compilers convert software (including
OS’s) into machine language (0,1)
Source
Code
Compile
Machine
Language
Note: It’s a one-way process.
Operating Systems
 Other OS Capabilities
 User Interface
 Commands
 GUI
 Multi-tasking
 Time-sharing
Scalability: The ability of a system to handle more
or less demand, more or fewer users; also a
product selling point – able to expand or
contract to accommodate growing configuration.
 A set of conventions governing the
treatment and especially the
formatting of data in an electronic
communications system.
Operating Systems
 Other OS Capabilities
 File Management
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Retrieve from secondary storage
Manage sharing among users
Naming conventions
Restrict/authorize access to files
Operating Systems
 Platforms
 Personal
 Workgroup
 Enterprise
Operating Systems - Utilities
 Utility Programs
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Check status of operations, hardware
Compress files, optimize space usage
Monitor performance / error-checking
Perform back-ups
Application Software
 What is it?
 Application software enables the power
of computers to give organizations,
companies, workgroups or individuals
the ability to solve problems or perform
tasks / work.
Application Software
 “I need application software that …”
 Proprietary (home-grown, in-house)
 COTS (commercial off-the-shelf)
 ASP
Application Software
Pros
Proprietary Get what you want
Modifications can be
accommodated
Cons
Takes a long time; expensive
Requires specialized skills
Not "acquisition-friendly"
COTS
ASP
Lower cost - since product
development shared by
many
Pay for customer-specific features
"Basic" business needs likely
met
Business process needs to be changed
"Hands-off" application
All eggs in one basket
"Basic" business needs likely
met
Customization unlikely
Vendor management required
Sensitive info in "their" control
Application Software
 Enterprise “Solutions”
 ERP’s – integrated programs that enable
vital business processes for entire
organization
 GIS
 File Management/ Knowledge
Management
Application Software
 Languages
 Keyword, symbols, structure, syntax
 Statements constructed so that
computers can do what we want
 Code = set of instructions, directing
computer to respond to binary input
Application Software
 Generations of Languages
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Machine language (1GL)
Assembler (2GL)
COBOL (3GL)
Essbase, Focus, SAS (4GL)
 The next frontier … Fifth Generation
 Pseudo code
Application Software
 Which one? What to consider?
 Hardware/OS platform
 Maintainability
 Available skillset
 Difficulty
 Future platforms
Application Software
 “Bugs” = Defect; Results:
 Immediate termination
 Gradual accumulation of errors
 5 – 15 bugs in every 1,000 LOC
 What causes them?
 Rush to market / competition
 Invisibility
Application Software
 “Personal Productivity” software
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MS Office
Financial
Taxes
Project Mgmt
Graphics