UNIT -3OPERATING

SYSTEM FUNDAMENTALS

A. S. Sardar

PERSONAL COMPUTER OPERATING SYSTEMS Microsoft Windows Microsoft Windows Versions UNIX Linux Apple Macintosh Operating Systems

MICROSOFT WINDOWS Microsoft Windows is a series of graphical

interface operating systems developed, marketed, and sold by Microsoft.

Microsoft introduced an operating environment named Windows on November 20, 1985 as a graphical operating system shell for MS-DOS in response to the growing interest in graphical user iterfaces.

Microsoft Windows came to dominate the world's personal computer market with over 90% market share, overtaking Mac OS, which had been introduced in 1984. 

was founded by Bill Gates and Paul Allen in Albuquerque.

PRODUCT’S OF MICROSOFT Operating Systems. Office Suites. Xbox for Games. Internet Explorer. Search Engine. Mail’s. Security. Servers. Cloud Storage Device. Visual Studio. Calling Device. Etc………….

WINDOWS TIMELINE

UNIX Unix is a multitasking, multi- user computer  operating system that exists in many variants. Unix was designed to be portable, multi-tasking and multi-user in a time-sharing configuration.  Unix systems are characterized by various concepts: the

use of plain text for storing data; a hierarchical file system; treating devices and certain types of inter-process communication (IPC) as files; and the use of a large number of software tools, small programs that can be strung together through a command line interpreter using pipes, as opposed to using a single monolithic program that includes all of the same functionality. 

LINUX Linux is a generic term referring to Unix-like graphical

user interface (GUI) based computer operating systems. It is Multi-user, Multitasking, Multiprocessor Has the X Windows GUI Coexists with other Operating Systems Runs on multiple platforms Includes the Source Code

WHY IS IT SIGNIFICANT? Powerful

Runs on multiple hardware platforms Users like its speed and stability No requirement for latest hardware

It’s “free” Licensed under GPL Vendors are distributors who package Linux

An operating system, or OS, is a software program that enables the computer hardware to communicate and operate with the computer software. Without a computer operating system, a computer would be useless.E.g.. Linux

Operating System

Multi-user A multi-user operating system allows for multiple users to use the same computer at the same time and/or different times.

Multiprocessing An operating system capable of supporting and utilizing more than one computer processor. Multitasking An operating system that is capable of allowing multiple software processes to run at the same time.

Multithreading Operating systems that allow different parts of a software program to run concurrently. Operating systems that would fall into this category are:

APPLE MACINTOSH OPERATING SYSTEMS The Macintosh or Mac is a series of personal

computers designed, developed, and marketed by Apple Inc.

The first Mac was introduced by Apple's then-chairman Steve Jobs on January 24, 1984; it was the first commercially successful personal computer to feature a mouse and a Graphical User Interface rather than a command-line Interface.

In 1998, Apple consolidated its multiple consumer-level desktop models into the iMac “all-in-one”. This was proven to be a sales success and saw the Macintosh brand revitalized.

APPLE MACINTOSH OPERATING SYSTEMS

Mac much to do with home, education, and creative professional markets.

It follows the vertical integration model in that Apple facilitates all aspects of its hardware and creates its own OS that is pre-installed on all Mac computers . Apple does not license Mac OS X for use on non-Apple computers.

The Macintosh project started in the late 1970s with Jef Raskin, an Apple employee who envisioned an easy-to-use, low-cost computer for the average consumer.

WINDOWS OS FILE SYSTEMS MS-DOS and Windows 95/98/NT/2000/XP allow use of FAT-16 or FAT-32. Windows NT/2000/XP uses NTFS (NT File System)Each directory entry is 32 bytes: • File Name (8 bytes) • Extension (3 bytes) • Attributes (1 byte) • Reserved (10 bytes) • Time (2 bytes) • Date (2 bytes) • Block number of first file block (2 bytes) • File size in bytes (4 bytes)Attributes (one-bit each): R: Read Only A: Archive (set when file modified, cleared when backed up) S: System File (file cannot be deleted by the del command) H: Hidden File (file is not listed with dir command) D: Directory V: Volume Label Note: FAT and directory entry both keep track of how many blocks in a file—could be inconsistency. FAT (versus Unix) keeps all information about a file in the directory entry rather than an Inode.

WINDOWS OS FILE SYSTEMS

NT/2000/XP File System (NTFS) Uses clusters (basically same as a block) as the unit

of disk allocation. A cluster consists of one or more physical sectors on the disk.

They are numbered by numbers called logical cluster numbers (LCNs).

Information about NTFS files stored as attributes: file name (names if there are aliases), creation time, security descriptor, unnamed data attribute (contents of the file).

WINDOWS OS FILE SYSTEMSMaster File Table (MFT) Special file containing one entry for each file in a volume. MFT

entry can be from 1KB to 4KB.

Info contained in an MFT entry about a file:

standard info such as time stamps, file size Fle’s name in Unicode (16-bit chars) and also an 8.3 DOS-style

name Security info Data for the file. If a small file this attribute can be stored in the

MFT entry (resident attribute vs. non-resident attribute).

PERMISSSIONS Right-Click on the appropriate folder or file.  Selecting "Properties" or "Sharing and Security" will

enter the Windows Security Management pane. Selecting (click once) any user name listed will

display the rights that user has in the bottom half of the pane.

 

PERMISSIONS 1 Full Control Allows: 1, 2, 3, 4, 5, 6, 7

 2.  Modify Allows: 2, 3, 4, 5, 6 3.  Read & Execute Allows: 3, 4  4.  List Folder Contents Allows: 4 (but cannot run programs) 

 5.  Read Allows: 5 (Implies: 4)

 6.  Write Allows: 6 (Implies:4 )

7.  Special Permissions Allows: Combinations 

PERMISSIONSBest PracticesCommonly used security practices suggest that all FILES should

have the following permissions. Owner  :  Read & Write        Group   :  Read Only        Others : Read Only

All DIRECTORIES/FOLDERS should have the following permissions.        Owner  : Read, Write & Execute        Group   : Read & Execute        Others : Read & Execute

WHAT ARE ADMINISTRATIVE TOOLS?

Administrative Tools is a folder in Control Panel that contains tools for system administrators and advanced users. The tools in the folder might vary depending on which version of Windows you are using.

Open Administrative Tools by clicking the Start button , and then clicking Control Panel. In the search box, typeadministrative tools, and then click Administrative Tools.

CONTROL PANEL Component Services. Configure and administer Component

Object Model (COM) components. Component Services is designed for use by developers and administrators.

Computer Management. Manage local or remote computers by using a single, consolidated desktop tool. Using Computer Management, you can perform many tasks, such as monitoring system events, configuring hard disks, and managing system performance.

Data Sources (ODBC). Use Open Database Connectivity (ODBC) to move data from one type of database (a data source) to another. For more information, see What is ODBC?

Event Viewer. View information about significant events, such as a program starting or stopping, or a security error, which are recorded in event logs.

CONTROL PANEL iSCSI Initiator. Configure advanced connections between storage devices on a

network. For more information, see What is Internet Small Computer System Interface (iSCSI)?

Local Security Policy. View and edit Group Policy security settings. Performance Monitor. View advanced system information about the central

processing unit (CPU), memory, hard disk, and network performance. Print Management. Manage printers and print servers on a network and perform

other administrative tasks. Services. Manage the different services that run in the background on your

computer. System Configuration. Identify problems that might be preventing Windows from

running correctly. For more information, see Using System Configuration. Task Scheduler. Schedule programs or other tasks to run automatically. For more

information, see Schedule a task. Windows Firewall with Advanced Security. Configure advanced firewall settings

on both this computer and remote computers on your network. Windows Memory Diagnostic. Check your computer's memory to see if it's

functioning properly.