course: computer platforms. topic: introduction to software and operating systems
TRANSCRIPT
COURSE:
COMPUTER PLATFORMS
Topic: INTRODUCTION TO SOFTWARE AND OPERATING SYSTEMS
OBJECTIVES
• Components of a computer system
• Interpret the basic functions of Operating System
• Files and directory structure
• Client-Server Model
• Network Operating System
COMPONENTS OF A COMPUTER SYSTEM
The computer system is basically
divided into 4 components:
1. Hardware
2. Operating System
3. Application programs
4. Users
Users
Application Programs
Operating system
Computer Hardware
ABSTRACT OVERVIEW
HARDWARE
This provides the Basic system
resources.
SYSTEM SOFTWARE
• Refers to the Operating system and all utility programs that manage computer resources at a low level.
• It includes compilers, loaders, linkers and debuggers.
APPLICATION PROGRAMS
A program or group of programs
designed for end users.
Examples: Word processing, Graphics,
Spreadsheets, Databases,
Games.
GOALS OF AN OPERATING SYSTEM
• To make the computer system convenient to use.
• To use the computer hardware in an efficient manner.
PURPOSE OF AN OPERATING SYSTEM
• The purpose of an operating system is to provide an environment in which a user may execute programs.
WHAT IS AN OPERATING SYSTEM?
• An Operating System is an interface between user and hardware of a computer system.
WHAT IS AN OPERATING SYSTEM?
• An Operating System is a system software which may be viewed as an organized collection of software consisting of procedures for operating a computer and providing an environment for execution of programs.
OTHER DEFINITIONS
• An Operating System is a control program.
• An Operating System is similar to a Government.
• An Operating System can be defined as a Resource Manager.
OTHER DEFINITIONS
• An Operating System is the layer between the H/W and the S/W
• An Operating System is a virtual computer manager
• Operating System is the first program run on a computer when the computer boots up
USER INTERFACE
A set of commands or menus through
which user communicates with the
program.
TYPES OF INTERFACES
• Command driven
• Menu driven
• Graphical user interface(GUI)
WAYS TO INTERACT WITH OPERATING SYSTEM
• OPERATING SYSTEM CALLS
• OPERATING SYSTEM COMMANDS
SYSTEM CALLS
System Calls provide the interface to a
running program and the O/S.
OPERATING SYSTEM COMMANDSUsers nay interact with the O/S directly
by means of O/S commands.
MULTIPROGRAMMING
• Multiprogramming was used as a technique to enhance the throughput efficiency.
• Overlapping interleaving computing of different jobs.
• More than one job is “ready” at the same time.
Different types of Multiprogramming Operating System
• Multitasking operating system
• Multiprocessing operating system
• Multi-user operating system
FUNCTIONS OF OPERATING SYSTEM
Memory management
Process management
Device management
Information management
Protection
Error Handling
FUNCTIONS OF OPERATING SYSTEM
Memory management
Process management
Device management
Information management
Protection
Error Handling
The o/s keeps track of the memory, what parts are in use and by whom.
FUNCTIONS OF OPERATING SYSTEM
Memory management
Process management
Device management
Information management
Protection
Error Handling
The o/s keeps track of The o/s keeps track of processors and the status processors and the status
of processes. It decidesof processes. It decides who will have a chance to who will have a chance to
use the processor.use the processor.
FUNCTIONS OF OPERATING SYSTEM
Memory management
Process management
Device management
Information management
Protection
Error Handling
The o/s keeps track of the devices,
channels, control units and decides what is an efficient way to allocate the device.
FUNCTIONS OF OPERATING SYSTEM
Memory management
Process management
Device management
Information management
Protection
Error Handling
O/S keeps track of the information, its location, use, status etc. and decides who gets use
of the resources, enforce protection requirements.
FUNCTIONS OF OPERATING SYSTEM
Memory management
Process management
Device management
Information management
Protection
Error Handling
An o/s is to protect the userAn o/s is to protect the user from unauthorized access from unauthorized access
of his files or data.of his files or data.And also it should protectAnd also it should protect
itself from usersitself from users
FUNCTIONS OF OPERATING SYSTEM
Memory management
Process management
Device management
Information management
Protection
Error Handling
An o/s must respond to errors by taking the appropriate actions.
FILE CONCEPT
File is a collection of related information.
It is named and is referred by its name.
Files are organized into directories for
easy access.
DIRECTORY STRUCTURE
ROOT D0
F1
D3D2
D21 D31
F311
F31F21
D1
D311
CLIENT-SERVER MODEL
User process(client process) sends the
request to a server process, which
when does the work and sends back
the answer.
CLIENT-SERVER ARCHITECTURE
CLIENT is an application that runs on a
personal computer or on a workstation
and relies on SERVER to perform some
operations such as managing files,
disk drives, printers or network traffic.
NETWORK OPERATING SYSTEM
The Software that enhances a basic
Operating System by adding Networking
Features.
Examples: Novell Netware, WINDOWS NT
• Operating system is an essential component of system software which consists of procedures for managing computer resources.
• Operating system functions primarily includes Memory, Process,Device, File management.