Transcript IT 10103

IT 10103
Introduction to Information Technology
CHAPTER 08 – Operating System
System Software
System Software?
Programs that control or maintain the
operations of the computer and its devices.
The interface between the user, application
software, and the computer’s hardware.
System Software
Two Types of System Software
Operating Systems
Utility Programs
System Software
Operating System Software
Coordinates all the activity of the computer
hardware
System Software
Operating System Software
Resides on the Hard Drive usually found on
the 1st Hard Drive Partition or Drive C:\
System Software
Operating System Functions
Starting A Computer
Providing a User Interface
Managing Programs
Managing Memory
Scheduling Jobs
Configuring Devices
Establishing Network Connections
Monitoring Performance
File Management
Controlling a Network
Administering Security
System Software
Starting A Computer
Booting a Computer
Cold Boot – Turning on the computer
Warm Boot – Restarting the computer
System Software
How does a personal computer boot up?
Step 1. Power supply
Step 4. Results of POST are
sends signal to components in system unit
compared with data in CMOS chip
Step 2. Processor
in floppy disk drive or CD/DVD
drive, and then hard disk
accesses BIOS to start
computer
Step 3. BIOS runs tests,
called the POST, to
check components such
as mouse, keyboard,
and adapter cards
Step 5. BIOS looks for system files
Step 6. Kernel (core) of operating
system loads into RAM
Step 7. Operating system loads
configuration information and
displays desktop on screen
System Software
Providing a User Interface
Controls how data is entered and how
information is displayed
Three Types:
Command-Line Interface
Menu-Driven Interface
Graphical User Interface (GUI)
System Software
Command-Line Interface
System Software
Menu-Driven Interface
System Software
Graphical User Interface (GUI)
System Software
Managing Programs
There are four ways an OS manages
programs:
System Software
Real-time operating system (RTOS)
Real-time operating systems are used to control
machinery, scientific instruments and industrial systems.
An RTOS typically has very little user-interface
capability, and no end-user utilities, since the system will
be a "sealed box" when delivered for use. A very
important part of an RTOS is managing the resources of
the computer so that a particular operation executes in
precisely the same amount of time every time it occurs.
In a complex machine, having a part move more quickly
just because system resources are available may be just
as catastrophic as having it not move at all because the
system is busy.
System Software
Single-user, single task
As the name implies, this operating system is
designed to manage the computer so that one
user can effectively do one thing at a time. The
Palm OS for Palm handheld computers is a good
example of a modern single-user, single-task
operating system.
System Software
Single-user, multi-tasking
This is the type of operating system most people
use on their desktop and laptop computers today.
Microsoft's Windows and Apple's MacOS
platforms are both examples of operating
systems that will let a single user have several
programs in operation at the same time. For
example, it's entirely possible for a Windows user
to be writing a note in a word processor while
downloading a file from the Internet while printing
the text of an e-mail message.
System Software
Multi-user
A multi-user operating system allows many
different users to take advantage of the
computer's resources simultaneously. The
operating system must make sure that the
requirements of the various users are balanced,
and that each of the programs they are using has
sufficient and separate resources so that a
problem with one user doesn't affect the entire
community of users. Unix, VMS and mainframe
operating systems, such as MVS, are examples
of multi-user operating systems
System Software
Multi-Processing
Supports two or more processors (CPU)
Aysmmetric:
one CPU does the work
of the system, the other
CPUs service user
requests.
Symmetric:
All processors can be
used by the system and
users alike. No CPU is
special.
System Software
Managing Memory
To optimize the use of random access
memory or RAM. One way to do this is to
utilize Virtual Memory
System Software
Virtual Memory
The OS allocates a portion of storage (usually
the hard drive) to function as additional RAM.
System Software
Virtual Memory
The OS allocates a portion of storage (usually
the hard drive) to function as additional RAM.
Step 1. The
operating system
transfers the least
recently used data
and program
instructions to disk
because memory is
needed for other
functions.
Step 2. The
operating system
transfers data and
program instructions
from disk to
memory when they
are needed.
System Software
Windows Vista ReadyBoost
Windows ReadyBoost lets users use a
removable flash memory device, such as a
USB thumb drive, to improve system
performance without opening the box.
Windows ReadyBoost can improve system
performance because it can retrieve data kept
on the flash memory more quickly than it can
retrieve data kept on the hard disk,
decreasing the time you need to wait for your
PC to respond.
System Software
Windows Vista ReadyBoost
ReadyBoost does not cache file writes—it's a
write-through cache. That way, you never lose
any precious data that's meant to be written to a
hard drive. After all, a flash memory key can get
yanked out of a system at any time. The cache
itself is encrypted using AES-128 encryption, so
no one can steal your flash memory key and
casually browse through the cache file to see
what you've been doing.
System Software
Scheduling Jobs
Determines the order in which jobs are
processed. A job is an operation the
processor manages.
Utilizes a Buffer – a segment of memory for
temporary storage of items until needed
Utilizes Spooling – sending a job to a buffer
instead of directly to a device (printers)
Utilizes a Queue – a list in the buffer of jobs
waiting to be completed
System Software
Configuring Devices
The OS configures through a Device Driver or
Driver. Each hardware component of a
computer has a device driver. It is how the
OS communicates with the hardware.
Plug-N-Play – the OS automatically configures
any new devices connected to the computer
System Software
Establishing a Network Connection
Provides the means of making a connection
to a network including the Internet
Usually a Web Browser is provided for the
Internet connection function
System Software
Monitoring Performance
A part of the OS that shows the performance
statistics of the system. Useful for
troubleshooting problems or just seeing how
well your system works.
(In Windows XP it is located under the
Task Manager Dialog Box)
System Software
File Management
Saving, Reading, Copying, Moving, Deleting
Windows Explorer is the primary file manager
in Windows XP
System Software
Controlling a Network
Some Operating Systems are specifically
designed to control networks. These types
are called Network Operating Systems (NOS).
They coordinate the activities of the network
System Software
Administering Security
The OS provides a way to control user access
through security authentication.
Example: Logging into this labs computers
System Software
System Utilities
A program that allows us to perform
maintenance or management of our
computers. These include File Managers,
Image Viewers, Uninstallers, Disk Scanners,
Disk Defragmenters, Diagnostics, Backup,
Screen Savers, Spyware/Adware Removers,
and Antivirus Utilities.
System Software
Stand-Alone Operating Systems
DOS
WINDOWS
MAC OS X
UNIX
LINUX
System Software
Network Operating System
NETWARE
WINDOWS SERVER
UNIX
LINUX
SOLARIS
System Software
Embedded Operating System
WINDOWS CE
WINDOWS MOBILE
PALM OS
SYMBIAN OS
System Software
Types of Utility Software
Antivirus Programs
Personal Firewalls
File Compression
Personal Computer Maintenance
System Software
Personal Firewall
System Software
QUESTIONS ?
System Software
BUYERS GUIDE 2006
PAGE 444
System Software
ASSIGNMENT 06
Buy a New PC Computer (Pretend)
You can choose whatever components you
want from any supplier or retailer.
Explain to me why you chose this computer
and what it will do for you. Also list the
individual components of the computer and
the final total cost of the system.
You have a budget of: $ 5,000.00
System Software
Some Starting Points:
System Resellers
www.dell.com
www.gateway.com
www.hp.com
Parts Resellers
www.newegg.com
www.mwave.com
www.buy.com
www.pricewatch.com