This chapter discusses file systems used by various operating systems. It describes the basic functions of file systems including organizing files into directories, establishing naming conventions, and providing file integrity and security. It then covers the file systems used by Windows (FAT16, FAT32, FAT64, NTFS), UNIX/Linux (ufs, ext), and Mac OS X (HFS+). The key components and features of these various file systems are outlined.
The document provides guidance on installing and upgrading operating systems. It discusses preparing for installation by checking hardware compatibility and obtaining necessary drivers. The installation process typically involves gathering system information, loading the installation program, configuring devices, copying files, and restarting. Migrating to a new OS may require upgrading existing systems or performing a clean installation, and it is best to test the process first on a representative computer before deploying widely. Training users is also recommended when transitioning to a new desktop operating system.
This document provides guidance on standard operating and maintenance procedures for file systems. It discusses file system maintenance techniques, such as creating an organized directory structure, finding and deleting unused files on a regular basis, and performing disk maintenance like defragmenting to optimize performance. Backup plans and software installation procedures are also covered. The document provides examples of directory structures and maintenance tasks for different operating systems including Windows, Linux/UNIX, and Mac OS X.
This chapter discusses operating system hardware components and their interaction with operating systems. It describes the basic features of CPUs like design type, speed, cache, buses, and scheduling. CPUs can be CISC or RISC and include elements like cores, clocks, caches, and address/data/control buses. Popular PC processors include Intel, AMD, and server chips from companies like Sun and HP. Hardware and operating systems evolved together with OSes taking advantage of new processor capabilities.
This document provides an overview and objectives for Chapter 1 of the textbook "Guide to Operating Systems". It discusses basic operating system concepts like kernels, resource managers, device drivers, and applications. It covers the history of operating system development from early mainframes to modern desktop and server OSs. It also differentiates between single-tasking and multitasking systems as well as single-user and multiuser OSs. Current common operating systems like Windows, Linux, and Mac OS are also listed.
This chapter discusses storage devices and technologies. It describes common disk storage options like hard drives, DVD/CD drives, removable drives, and flash drives. Hard drive interfaces like IDE, SATA, SCSI, and SAS are explained. The chapter also covers optical disc technologies like CDs, DVDs, and Blu-Ray discs. Network storage options such as SAN, NAS, cloud storage, and tape backup systems are introduced along with their capacities and features.
This chapter discusses how operating systems interface with input and output devices through device drivers and adapters. It explains the general process for installing and configuring new devices, which involves installing software drivers, connecting the hardware, and configuring the device. It covers how operating systems use device drivers to communicate with hardware and support various device features. It also describes how to install and update drivers in Windows, Linux/UNIX, and Mac operating systems. Popular input devices like mice, keyboards, touchscreens, and digital pads are discussed.
This chapter describes popular desktop and server operating systems. It discusses early Microsoft operating systems like MS-DOS, Windows 3.x, and Windows 95. It then covers Windows 98/Me, Windows NT, Windows 2000, and Windows XP. It provides details on features, versions, and capabilities of each. The chapter also examines current operating systems including Windows Server 2003/R2, Windows Vista, Windows Server 2008/R2, and Windows 7.
This document provides guidance on resource sharing over a network in Windows and UNIX/Linux operating systems. It discusses setting up file, disk, and printer sharing through server network operating systems like Windows Server and UNIX/Linux. It covers configuring user accounts, groups, permissions and security to control access to shared resources. The document also provides examples of how to set up groups, assign permissions, and share disks and files on both Windows Server and UNIX/Linux networks.
The document provides guidance on installing and upgrading operating systems. It discusses preparing for installation by checking hardware compatibility and obtaining necessary drivers. The installation process typically involves gathering system information, loading the installation program, configuring devices, copying files, and restarting. Migrating to a new OS may require upgrading existing systems or performing a clean installation, and it is best to test the process first on a representative computer before deploying widely. Training users is also recommended when transitioning to a new desktop operating system.
This document provides guidance on standard operating and maintenance procedures for file systems. It discusses file system maintenance techniques, such as creating an organized directory structure, finding and deleting unused files on a regular basis, and performing disk maintenance like defragmenting to optimize performance. Backup plans and software installation procedures are also covered. The document provides examples of directory structures and maintenance tasks for different operating systems including Windows, Linux/UNIX, and Mac OS X.
This chapter discusses operating system hardware components and their interaction with operating systems. It describes the basic features of CPUs like design type, speed, cache, buses, and scheduling. CPUs can be CISC or RISC and include elements like cores, clocks, caches, and address/data/control buses. Popular PC processors include Intel, AMD, and server chips from companies like Sun and HP. Hardware and operating systems evolved together with OSes taking advantage of new processor capabilities.
This document provides an overview and objectives for Chapter 1 of the textbook "Guide to Operating Systems". It discusses basic operating system concepts like kernels, resource managers, device drivers, and applications. It covers the history of operating system development from early mainframes to modern desktop and server OSs. It also differentiates between single-tasking and multitasking systems as well as single-user and multiuser OSs. Current common operating systems like Windows, Linux, and Mac OS are also listed.
This chapter discusses storage devices and technologies. It describes common disk storage options like hard drives, DVD/CD drives, removable drives, and flash drives. Hard drive interfaces like IDE, SATA, SCSI, and SAS are explained. The chapter also covers optical disc technologies like CDs, DVDs, and Blu-Ray discs. Network storage options such as SAN, NAS, cloud storage, and tape backup systems are introduced along with their capacities and features.
This chapter discusses how operating systems interface with input and output devices through device drivers and adapters. It explains the general process for installing and configuring new devices, which involves installing software drivers, connecting the hardware, and configuring the device. It covers how operating systems use device drivers to communicate with hardware and support various device features. It also describes how to install and update drivers in Windows, Linux/UNIX, and Mac operating systems. Popular input devices like mice, keyboards, touchscreens, and digital pads are discussed.
This chapter describes popular desktop and server operating systems. It discusses early Microsoft operating systems like MS-DOS, Windows 3.x, and Windows 95. It then covers Windows 98/Me, Windows NT, Windows 2000, and Windows XP. It provides details on features, versions, and capabilities of each. The chapter also examines current operating systems including Windows Server 2003/R2, Windows Vista, Windows Server 2008/R2, and Windows 7.
This document provides guidance on resource sharing over a network in Windows and UNIX/Linux operating systems. It discusses setting up file, disk, and printer sharing through server network operating systems like Windows Server and UNIX/Linux. It covers configuring user accounts, groups, permissions and security to control access to shared resources. The document also provides examples of how to set up groups, assign permissions, and share disks and files on both Windows Server and UNIX/Linux networks.
This chapter discusses network connectivity and operating systems. It explains networking basics such as topologies, hardware, protocols, and how devices connect to networks. It describes client and server operating systems and their roles. It also covers common network protocols like TCP/IP, Ethernet, wireless technologies, and how they are configured in operating systems. Network devices, addressing, and automatic configuration using DHCP are also summarized.
Enhanced Embedded Linux Board Support Package Field Upgrade – A Cost Effectiv...ijesajournal
Latest technology, new features and kernel bug fixes shows a need to explore a cost-effective and quick
upgradation of Embedded Linux BSP of Embedded Controllers to replace the existing U-Boot, Linux kernel,
Dtb file, and JFFS2 File system. This field upgrade technique is designed to perform an in-the-field flash
upgrade while the Linux is running. On successful build, the current version and platform specific information
will be updated to the script file and further with this technique the file system automates the upgrade
procedure after validating for the version information from the OS-release and if the version is different it will
self-extract and gets installed into the respective partitions. This Embedded Linux BSP field upgrade invention
is more secured and will essentially enable the developers and researchers working in this field to utilize this
method which can prove to be cost-effective on the field and beneficial to the stake holder.
This chapter describes different types of modems and communication devices. It discusses analog modem architecture, including how analog modems modulate and demodulate signals. It also covers digital modems for wireless, ISDN, cable, DSL, and satellite connections. Finally, it describes how to configure modems and Internet connections in various operating systems like Windows, Linux, and Mac OS X.
Selecting and Installing Operating SystemAmir Villas
The document provides an overview of installing and troubleshooting various Windows operating systems, including DOS, Windows 3.1, 95/98/Me, NT/2000/XP. It discusses selecting an OS based on system requirements, starting the setup program from various sources, planning for upgrades or clean installs, and addressing common installation problems like hardware incompatibilities or errors reading from the installation media.
The document provides an overview of the Microsoft Disk Operating System (MS-DOS). It describes the four major components of MS-DOS: the operating system loader, BIOS, user interface (Command.com), and kernel. The kernel provides services like file management, memory management, device I/O, and process control. It manages memory using a pool of variable blocks and supports conventional, expanded, and extended memory. MS-DOS identifies block and character devices differently and uses functions and handles to communicate with devices like keyboards, displays, and printers. While it can run multiple programs, MS-DOS is a single-tasking operating system.
This document provides an overview of storage technologies and concepts. It discusses the history of storage technologies from early drum memory to modern hard disks and solid state drives. Key concepts covered include RAID configurations, disk interfaces like SATA and SAS, tape storage technologies, storage controllers, and virtual tape libraries. The document concludes with a discussion of Kryder's law and projections for future disk capacity growth.
1. The document discusses various methods for managing memory in the Linux kernel, including physical memory, virtual memory, page tables, and different allocators like kmalloc, vmalloc, and SLAB for allocating memory to processes and the kernel.
2. It explains concepts like physical vs virtual addresses, page tables that map virtual to physical memory, and the Memory Management Unit (MMU) that handles virtual address translation.
3. Different allocators like kmalloc, vmalloc and SLAB are used depending on the size and properties of the memory needed, with kmalloc and SLAB handling physically contiguous memory and vmalloc only requiring virtual contiguity.
This document summarizes different types of storage drives - hard disk drives (HDDs), solid state drives (SSDs), and hybrid drives (SSHDs). It describes the basic components and workings of HDDs, including disks, read/write heads, motors, and interfaces. SSDs have no moving parts and offer faster access times than HDDs but lower capacity. SSHDs combine aspects of HDDs and SSDs. The document provides an overview of the key differences between HDDs and SSDs in terms of performance, reliability, size, and power consumption.
Linux is a widely used open source operating system kernel that can also refer to full operating system distributions. It is commonly used in embedded systems due to its portability, modularity, and ability to run on hardware with limited resources. Device drivers can be dynamically loaded and unloaded from the Linux kernel as modules, allowing new functionality to be added without rebooting the system. This makes Linux well-suited for embedded device development.
The document discusses operating systems and their components. It defines an operating system as a program that acts as an intermediary between the user and computer hardware. It describes the typical components of a computer system as hardware, operating system, application programs, and users. It also provides examples of common operating systems commands like DIR, DEL, DATE and TIME.
This document discusses disk storage and formatting. It explains that disks store data magnetically or optically using transitions between positive and negative polarity or pits and lands. Disk space is organized into cylinders, tracks, heads, and sectors. Low-level formatting creates this structure and high-level formatting creates file systems like FAT16, FAT32, and NTFS that organize data into clusters and directories. The document compares features of different file systems and operating system compatibility.
I/O System and Case Study of Operating System its easy way to find how the I/O's are connected with the Operating System and And the mechanism of the Operating System
Windows 2000 architecture has a layered design with a kernel mode and user mode. The kernel mode consists of the hardware abstraction layer, kernel, and executive services which have unrestricted system access. The user mode contains subsystems and has limited resource access. The kernel schedules processes and handles interrupts, synchronization, and recovery. Executive services provide common functions like I/O management, security, and power management through components like the object manager and process manager. Environment subsystems allow running applications from other operating systems by converting their API calls.
Case study of windows a product of microsoft including the history and related to operating system with MS-DOS its scheduling, networking, performance, etc. It also contains the windows architecture, it's system components like kernel, and scheduling through threads in windows.
This document discusses configuring devices in Windows, including identifying device resource needs, viewing and changing resource assignments, updating drivers, and disabling devices. It covers default interrupt requests, I/O addresses, memory addresses, and DMA channel assignments. Plug and play and ACPI are described as enabling automatic configuration and power management. Methods for installing PnP and non-PnP devices are provided.
The document discusses the history and development of Linux and Windows operating systems. It mentions that Linus Torvalds developed the initial Linux kernel version 0.0.1 in 1991 as an open source operating system. Microsoft developed Windows NT to support both OS/2 and POSIX APIs, though it later switched to the Win32 API. The document also compares advantages and disadvantages of Linux versus Windows, such as Linux being more stable and secure while Windows has a larger software selection.
This document discusses disk and file system concepts including:
- Creating file systems using newfs and how it connects to mkfs
- Mounting file systems manually, via fstab, and using volume manager
- Identifying mounted file systems using mount, df, and mnttab
- Repairing file systems using fsck and handling recoverable vs unrecoverable damage
- Benefits of journaling file systems like reduced reboot time and data retention
OPERATING SYSTEM AND SERVICES
TOPICS
1 Dos – History, Files and Directories
2 Internal and External Commands
3 Batch Files
4 Types of O.S.
Assignment:
• Draw the block diagram for computers and explain the various the components in few words, viz. Input, Storage, Processing, Output and Control
This document discusses disk formatting and partitioning. It explains that low-level formatting divides a disk into sectors that can be read and written to by adding headers, data, and trailers. Logical formatting then creates a file system by adding data structures to map free and allocated space. Disks can also be used as raw disks without a file system for things like swap space. Boot blocks contain bootstrap programs to initialize the system and load the operating system from a fixed location on the boot disk. Disk controllers can manage bad blocks by marking them or replacing them with spare sectors.
The document discusses the logical structure and partitioning of hard disks. It explains that the hard disk can be divided into logical partitions beyond its physical structure. This allows an operating system to access different sections of the hard disk as separate drives. There are two types of partitions - primary partitions that can directly contain an operating system, and extended partitions that allow creating additional logical drives beyond the 4 primary limit. Partitioning provides benefits like organizing data from multiple users, installing multiple operating systems, improving storage efficiency, and increasing data security through backups.
This chapter discusses network connectivity and operating systems. It explains networking basics such as topologies, hardware, protocols, and how devices connect to networks. It describes client and server operating systems and their roles. It also covers common network protocols like TCP/IP, Ethernet, wireless technologies, and how they are configured in operating systems. Network devices, addressing, and automatic configuration using DHCP are also summarized.
Enhanced Embedded Linux Board Support Package Field Upgrade – A Cost Effectiv...ijesajournal
Latest technology, new features and kernel bug fixes shows a need to explore a cost-effective and quick
upgradation of Embedded Linux BSP of Embedded Controllers to replace the existing U-Boot, Linux kernel,
Dtb file, and JFFS2 File system. This field upgrade technique is designed to perform an in-the-field flash
upgrade while the Linux is running. On successful build, the current version and platform specific information
will be updated to the script file and further with this technique the file system automates the upgrade
procedure after validating for the version information from the OS-release and if the version is different it will
self-extract and gets installed into the respective partitions. This Embedded Linux BSP field upgrade invention
is more secured and will essentially enable the developers and researchers working in this field to utilize this
method which can prove to be cost-effective on the field and beneficial to the stake holder.
This chapter describes different types of modems and communication devices. It discusses analog modem architecture, including how analog modems modulate and demodulate signals. It also covers digital modems for wireless, ISDN, cable, DSL, and satellite connections. Finally, it describes how to configure modems and Internet connections in various operating systems like Windows, Linux, and Mac OS X.
Selecting and Installing Operating SystemAmir Villas
The document provides an overview of installing and troubleshooting various Windows operating systems, including DOS, Windows 3.1, 95/98/Me, NT/2000/XP. It discusses selecting an OS based on system requirements, starting the setup program from various sources, planning for upgrades or clean installs, and addressing common installation problems like hardware incompatibilities or errors reading from the installation media.
The document provides an overview of the Microsoft Disk Operating System (MS-DOS). It describes the four major components of MS-DOS: the operating system loader, BIOS, user interface (Command.com), and kernel. The kernel provides services like file management, memory management, device I/O, and process control. It manages memory using a pool of variable blocks and supports conventional, expanded, and extended memory. MS-DOS identifies block and character devices differently and uses functions and handles to communicate with devices like keyboards, displays, and printers. While it can run multiple programs, MS-DOS is a single-tasking operating system.
This document provides an overview of storage technologies and concepts. It discusses the history of storage technologies from early drum memory to modern hard disks and solid state drives. Key concepts covered include RAID configurations, disk interfaces like SATA and SAS, tape storage technologies, storage controllers, and virtual tape libraries. The document concludes with a discussion of Kryder's law and projections for future disk capacity growth.
1. The document discusses various methods for managing memory in the Linux kernel, including physical memory, virtual memory, page tables, and different allocators like kmalloc, vmalloc, and SLAB for allocating memory to processes and the kernel.
2. It explains concepts like physical vs virtual addresses, page tables that map virtual to physical memory, and the Memory Management Unit (MMU) that handles virtual address translation.
3. Different allocators like kmalloc, vmalloc and SLAB are used depending on the size and properties of the memory needed, with kmalloc and SLAB handling physically contiguous memory and vmalloc only requiring virtual contiguity.
This document summarizes different types of storage drives - hard disk drives (HDDs), solid state drives (SSDs), and hybrid drives (SSHDs). It describes the basic components and workings of HDDs, including disks, read/write heads, motors, and interfaces. SSDs have no moving parts and offer faster access times than HDDs but lower capacity. SSHDs combine aspects of HDDs and SSDs. The document provides an overview of the key differences between HDDs and SSDs in terms of performance, reliability, size, and power consumption.
Linux is a widely used open source operating system kernel that can also refer to full operating system distributions. It is commonly used in embedded systems due to its portability, modularity, and ability to run on hardware with limited resources. Device drivers can be dynamically loaded and unloaded from the Linux kernel as modules, allowing new functionality to be added without rebooting the system. This makes Linux well-suited for embedded device development.
The document discusses operating systems and their components. It defines an operating system as a program that acts as an intermediary between the user and computer hardware. It describes the typical components of a computer system as hardware, operating system, application programs, and users. It also provides examples of common operating systems commands like DIR, DEL, DATE and TIME.
This document discusses disk storage and formatting. It explains that disks store data magnetically or optically using transitions between positive and negative polarity or pits and lands. Disk space is organized into cylinders, tracks, heads, and sectors. Low-level formatting creates this structure and high-level formatting creates file systems like FAT16, FAT32, and NTFS that organize data into clusters and directories. The document compares features of different file systems and operating system compatibility.
I/O System and Case Study of Operating System its easy way to find how the I/O's are connected with the Operating System and And the mechanism of the Operating System
Windows 2000 architecture has a layered design with a kernel mode and user mode. The kernel mode consists of the hardware abstraction layer, kernel, and executive services which have unrestricted system access. The user mode contains subsystems and has limited resource access. The kernel schedules processes and handles interrupts, synchronization, and recovery. Executive services provide common functions like I/O management, security, and power management through components like the object manager and process manager. Environment subsystems allow running applications from other operating systems by converting their API calls.
Case study of windows a product of microsoft including the history and related to operating system with MS-DOS its scheduling, networking, performance, etc. It also contains the windows architecture, it's system components like kernel, and scheduling through threads in windows.
This document discusses configuring devices in Windows, including identifying device resource needs, viewing and changing resource assignments, updating drivers, and disabling devices. It covers default interrupt requests, I/O addresses, memory addresses, and DMA channel assignments. Plug and play and ACPI are described as enabling automatic configuration and power management. Methods for installing PnP and non-PnP devices are provided.
The document discusses the history and development of Linux and Windows operating systems. It mentions that Linus Torvalds developed the initial Linux kernel version 0.0.1 in 1991 as an open source operating system. Microsoft developed Windows NT to support both OS/2 and POSIX APIs, though it later switched to the Win32 API. The document also compares advantages and disadvantages of Linux versus Windows, such as Linux being more stable and secure while Windows has a larger software selection.
This document discusses disk and file system concepts including:
- Creating file systems using newfs and how it connects to mkfs
- Mounting file systems manually, via fstab, and using volume manager
- Identifying mounted file systems using mount, df, and mnttab
- Repairing file systems using fsck and handling recoverable vs unrecoverable damage
- Benefits of journaling file systems like reduced reboot time and data retention
OPERATING SYSTEM AND SERVICES
TOPICS
1 Dos – History, Files and Directories
2 Internal and External Commands
3 Batch Files
4 Types of O.S.
Assignment:
• Draw the block diagram for computers and explain the various the components in few words, viz. Input, Storage, Processing, Output and Control
This document discusses disk formatting and partitioning. It explains that low-level formatting divides a disk into sectors that can be read and written to by adding headers, data, and trailers. Logical formatting then creates a file system by adding data structures to map free and allocated space. Disks can also be used as raw disks without a file system for things like swap space. Boot blocks contain bootstrap programs to initialize the system and load the operating system from a fixed location on the boot disk. Disk controllers can manage bad blocks by marking them or replacing them with spare sectors.
The document discusses the logical structure and partitioning of hard disks. It explains that the hard disk can be divided into logical partitions beyond its physical structure. This allows an operating system to access different sections of the hard disk as separate drives. There are two types of partitions - primary partitions that can directly contain an operating system, and extended partitions that allow creating additional logical drives beyond the 4 primary limit. Partitioning provides benefits like organizing data from multiple users, installing multiple operating systems, improving storage efficiency, and increasing data security through backups.
The document discusses disk partitioning, formatting, and different types of storage in Windows Server 2008. It defines basic disk storage using primary and extended partitions, and dynamic disk storage which allows volumes to span multiple disks. The different types of dynamic storage volumes are described - simple, spanned, striped, mirrored, and RAID-5. Steps are provided to create each type of volume on dynamic disks in Windows Server 2008.
Comparison of android and black berry forensic techniquesYury Chemerkin
As digital data is omnipresent now, the digital forensics has quickly become a legal necessity. Mobile devices have quickly grown and extend their own features which simplifying makes them less unique. Developers API, SDK, NDK provide great opportunity to build live, DLP or spyware for data extracting.
http://hakin9.org/hakin9-extra-412/
Major Google Algorithm Updates: A Brief OverviewOneThingMKT
Major Google algorithm updates include Panda, Penguin, Hummingbird, and Pigeon. Panda lowered the rank of sites with thin, low-quality content while increasing high-quality news sites. Penguin penalized sites using link schemes to boost rankings, while Hummingbird focused on user intent and providing deeper context search results. Pigeon aimed to improve local search results related to geographic location.
An Advanced SEO presentation that was done for the 2015 BlogPaws conference. Touching on semantic SEO including Latent Semantic Indexing, Schema/Microdata, technical seo and more, all presented in a way that was geared towards bloggers.
At the MnSearch Snippet #13 event held at Spyder Trap in Minneapolis, MN on April 30, 2014, Joe Wilebski presented his slidedeck "Panda, Penguin, Hummingbird."
What One Digital Forensics Expert Found on Hundreds of Hard Drives, iPhones a...Blancco
Do organizations have a defined process for wiping sensitive company information before discarding/reselling old drives and mobile devices?
In this webinar, Randy F. Smith and data security experts from Blancco Technology Group explore the following topics:
- How easily residual data can be recovered from hard drives and mobile devices
- The risks leftover data can pose to organizations
- The most secure ways to wipe company data from end-of-life devices and drives
Brev loc cloud data storage, backup and recovery presdanmraz
This document discusses data backup and recovery solutions, specifically Brevard Local Cloud. It notes that data loss can be catastrophic for businesses and outlines potential causes of data loss like hardware and human errors. Brevard Local Cloud is presented as a local backup solution where a user's data is backed up every 15 minutes to storage in Brevard County. The service provides up to 4 devices with 100GB storage, remote access, version restoration, and assistance for $35 per month.
The document discusses disk formatting, which prepares a data storage device. Formatting involves low-level formatting to subdivide tracks into blocks, partitioning to allow operating system access, and high-level formatting to set up a file system. Advanced format uses larger sectors for storage efficiency and error correction at higher densities. Formatting operations create the structure of sectors with gaps, sync marks, address marks, data, and error correction codes. Methods to check partition alignment on Windows include using the wmic command to view starting offsets.
Managing windows xp file systems and storage.2012.university duhok.bioloy.das...Dashty Rihany
This document discusses managing file systems and storage in Windows XP. It covers topics such as basic storage using partitions, dynamic storage using volumes, different file systems like NTFS, FAT, and FAT32, and utilities for disk management. Various activities are described to demonstrate tasks in Windows XP like creating and deleting partitions, converting between basic and dynamic disks, mounting volumes, and changing drive letters. The document also discusses file sharing, compression, burning CDs, using offline files, and folder redirection.
File systems organize and store data on various storage media like hard drives. They consist of structures like directories and files to track allocated space, file names and locations. Key functions include managing free space, directories, and file storage locations. Common file systems include FAT, NTFS, disk, flash, tape, database, network and special purpose file systems. File systems use inodes, directories, block allocation maps and other metadata to organize and track files.
This presentation was done by Raaj Paatkar at Mumbai SEO & SMM Meetup on March 30, 2014. It covers SEO strategies to rank in Google in face of punishing Google updates like Panda, Penguin and Hummingbird.
File carving is a process used in computer forensics to recover deleted files from unallocated space by analyzing fragments and reassembling them based on file headers and footers without relying on file system metadata. It works by searching raw data block by block for header and footer values to extract files. Common file carving tools include Foremost, Scalpel, and Photorec. New carving techniques like SmartCarving can recover even fragmented files through preprocessing, classifying fragments, and reassembling them in the proper sequence.
This document provides an overview of FAT and NTFS filing systems. It discusses key terms like files, directories, sectors, and clusters. FAT was first developed by Bill Gates in 1976 and includes versions like FAT12, FAT16, and FAT32. NTFS was developed later by Microsoft for Windows NT. It provides more security, reliability, and efficiency compared to FAT. The document outlines the advantages and disadvantages of both filing systems.
Disk drives map logical blocks of data to physical sectors sequentially, beginning with sector 0 on the outermost track and proceeding inward. Sectors are arranged in cylinders from outer to inner, and tracks within cylinders are mapped in order. Defective sectors are hidden by substituting spare sectors elsewhere. The number of sectors per track and bit density can vary depending on whether constant linear velocity (uniform bit density) or constant angular velocity (uniform rotation speed with decreasing density outward) is used.
Partitioning a hard drive involves creating, deleting, and formatting partitions to organize and manage the drive's storage space. It is commonly done when purchasing a new hard drive. Using disk management built into Windows, you can create partitions by selecting "New Simple Volume" on unallocated space. You can delete partitions by right clicking the unwanted partition and selecting "Delete Volume." Formatting a partition allows changing its file system or wiping data; right click the partition and select "Format" to begin this process. Partitioning provides benefits like independent storage areas that won't break other partitions if one fails, easier data organization, and the ability to encrypt partitions for security.
This document discusses data recovery techniques using macroscopic methods. It introduces scanning probe microscopy, specifically atomic force microscopy (AFM) and magnetic force microscopy (MFM). AFM uses a sharp tip attached to a flexible cantilever to produce topographic images of surfaces at an atomic scale. MFM similarly uses a magnetic tip to image magnetic fields. The document compares AFM and MFM, and discusses their advantages and disadvantages for data recovery applications.
The document discusses Microsoft file structures. It explains that clusters contain sectors and store file data, with cluster size varying by file system. It describes the master boot record containing partition tables and the file allocation table (FAT) or master file table (NTFS) storing file metadata. Finally, it notes that deleted files have metadata changed in FAT/NTFS and may remain recoverable from slack space.
Windows Forensics- Introduction and AnalysisDon Caeiro
This document provides an overview of file systems and disk structures relevant to computer forensics investigations. It discusses key components of file allocation tables (FAT) and file systems like FAT12, FAT16 and FAT32. It also covers the New Technology File System (NTFS) used in Windows, including the master file table and how files are stored as either resident or non-resident attributes. The document also examines disk partitioning, the master boot record, and startup processes for Windows, MS-DOS, and other operating systems. Understanding these fundamental concepts is important when acquiring or analyzing data from a suspect's computer.
The document discusses file systems in Windows. It describes the FAT and NTFS file systems used in Windows. FAT stores file information in a file allocation table and uses a linked list data structure. NTFS stores file data and metadata in a master file table. Key differences are that NTFS supports larger storage, permissions, and compression while FAT32 is more compatible across platforms but less secure locally.
Course 102: Lecture 26: FileSystems in Linux (Part 1) Ahmed El-Arabawy
This lecture introduces some concepts about FileSystems in Linux.
Video for this lecture on youtube:
http://www.youtube.com/watch?v=9jj1QOokACo
Check the other Lectures and courses in
http://Linux4EnbeddedSystems.com
or Follow our Facebook Group at
- Facebook: @LinuxforEmbeddedSystems
Lecturer Profile:
Ahmed ElArabawy
- https://www.linkedin.com/in/ahmedelarabawy
The document discusses file systems and how they organize files on storage devices. It covers key concepts like directories, file allocation tables (FAT), file attributes, and different file systems like FAT, FAT32, NTFS, and Ext3. It compares the capabilities and limitations of different file systems and how they are used depending on factors like hardware, software, security needs and disk size.
The document discusses file systems and their components. It covers directory organization, allocation schemes, file attributes, operations, structures and access methods. It also compares different file systems like FAT, FAT32 and NTFS in terms of their compatibility, volume size limits, fault tolerance and other advantages/disadvantages.
The document discusses Microsoft file structures. It explains that sectors are grouped into clusters to store files, and that clusters are numbered sequentially starting at 0 in NTFS and 2 in FAT. The Master Boot Record stores partition information, and files deleted in FAT have their directory entry marked with a sigma while files deleted in NTFS are removed from the Master File Table listing. The Master File Table in NTFS tracks file metadata in records containing attribute IDs.
The document discusses file systems and their components. It describes how files are organized logically and mapped to physical storage. It covers key file system concepts like directories, file allocation schemes, file attributes, and file operations. It also summarizes common file systems like FAT, FAT32, and NTFS and compares their features such as supported drive sizes, cluster sizes, and compatibility with different operating systems.
The document discusses and compares different file systems, including FAT, FAT32, NTFS, and their key features and limitations. FAT is the oldest file system and was designed for small disks and simple structures. It uses a file allocation table to organize files. NTFS is proprietary to Windows and offers improvements like larger volume sizes, security features like encryption, compression and quotas. It also has better performance, especially on large volumes.
UNIT 4-UNDERSTANDING VIRTUAL MEMORY.pptxLeahRachael
Virtual memory uses demand paging to improve memory usage by only loading pages from disk into RAM when needed by the CPU. This allows programs to be larger than physical RAM since unused pages remain on disk. When a program accesses a page not in RAM, a page fault occurs and the OS loads the required page from disk transparently. Demand paging allows more efficient use of physical RAM and faster program startup compared to loading the entire program at once.
- FAT (File Allocation Table) was the original file system developed by Microsoft for early versions of Windows to organize files on disks. It stored metadata in a file allocation table and used a linked list data structure.
- NTFS (New Technology File System) was developed later to replace FAT as disk sizes increased. NTFS uses more advanced data structures like B-trees and provides features like security, compression, encryption, and journaling.
- In NTFS, files are stored in clusters across the disk. The master file table stores metadata about every file and directory, including attributes like security and extended properties. System files also store information to enable features like recoverability.
File systems provide an organized way to store and access data on storage devices like hard drives. The Linux file system hierarchy standard defines a common structure across Linux distributions with directories like /bin, /etc, /home, /usr, and /var. Common Linux file system types include ext2, ext3, ext4 for disks, initramfs for RAM, and JFFS2 for flash storage. File systems can also be distributed across a network using NFS or optimized for specific purposes like squashfs for read-only files. Partitions divide available storage space to better manage files, users, and data security.
Disk and File System Management in LinuxHenry Osborne
This document discusses disk and file system management in Linux. It covers MBR and GPT partition schemes, logical volume management, common file systems like ext4 and XFS, mounting file systems, and file system maintenance tools. It also discusses disk quotas, file ownership, permissions, and the umask command for setting default permissions.
This document provides an overview of file systems and managing files on Windows PCs. It discusses different file systems like FAT, FAT32, NTFS, and CDFS. It covers basic file management tasks in Windows like selecting, copying, moving, deleting and renaming files. It also describes file attributes, troubleshooting common file errors, backing up files, and using command prompt commands to manage files from the command line interface.
This document provides an overview of Windows file systems and how they are used for digital forensics investigations. It discusses the File Allocation Table (FAT) file system and how it tracks file clusters. It also describes the New Technology File System (NTFS) and how it stores file metadata and tracks unused data clusters. The document outlines how file deletion, renaming and moving works in Windows, and artifacts that can be recovered from deleted files. It identifies several useful file types for forensic analysis, like shortcut files, the Recycle Bin, print spool files and registry keys.
The document discusses file systems and different types of file systems. It provides information on what a file and file system is, the main components of a file system including directories and file allocation methods. It also summarizes the key differences between common file systems like FAT32, NTFS, and exFAT and describes their ideal usage cases. Different structures for organizing files in directories like single-level, two-level, and tree-structured directories are also covered along with the advantages of maintaining directories.
The document discusses various topics related to file systems, partitions, and the Windows boot process. It describes the FAT and NTFS file systems, how partitions and volumes are used to organize disk space, and the steps involved in booting Windows, including the roles of the boot loader, kernel, and services.
The document discusses file management in operating systems. It covers topics such as the basic functions of a file system, different file organization techniques like sequential, direct and indexed sequential, file structures, file allocation methods like contiguous, linked and indexed, free space management using free lists or bitmaps, file access control, and backup techniques. File systems are responsible for organizing files and managing access to data on storage devices in a way that facilitates navigation and protects data from corruption or loss.
The document discusses object-oriented programming concepts in JavaScript, including creating custom objects using object literals, constructor functions, and the new operator. It provides examples of defining object properties and methods, and using nested functions to manage the state of buttons for a poker game application. The key topics covered are creating custom objects, defining object properties and methods, object constructor functions, and instantiating objects.
This document discusses using JavaScript to program web forms. It covers exploring the forms and elements objects to reference form fields and values. Methods are presented for setting field values, navigating between fields, and working with selection lists, radio buttons, check boxes, and hidden fields. The document also discusses formatting numeric values, applying form events, appending form data to URLs, and using regular expressions to extract data. Validation techniques like validating credit card numbers are also mentioned.
Chapter 12 Working with Document nodes and style sheetsDr. Ahmed Al Zaidy
This document discusses working with document nodes and style sheets in JavaScript. It covers exploring the node tree structure, creating element and text nodes, and appending nodes to documents. It also discusses creating external and embedded style sheets, adding them to documents, and enabling or disabling style sheets through JavaScript. The document provides examples of how to loop through child nodes, access node properties, and restructure node trees by moving nodes. It also explains working with attribute nodes and style sheet rules.
This document discusses working with events and styles in JavaScript. It covers creating event handlers, using the event object, exploring object properties, working with mouse and keyboard events, and controlling event propagation. Specific topics include adding and removing event listeners, changing inline styles, creating object collections with CSS selectors, and changing the cursor style. The overall goal is to teach how to build interactive elements that respond to user input through events.
Chapter 10 Exploring arrays, loops, and conditional statementsDr. Ahmed Al Zaidy
This document discusses using arrays, loops, and conditional statements in JavaScript. It begins by introducing the objectives of creating an array, working with array properties and methods, creating a for loop, using comparison and logical operators, and creating an if conditional statement. It then provides examples and explanations of creating and populating arrays, extracting values from arrays, sorting arrays, and using arrays as data stacks. The overall purpose is to demonstrate various array and loop techniques to generate a monthly calendar using JavaScript.
This document provides an overview of JavaScript programming concepts including:
1) It discusses server-side and client-side programming, with JavaScript being a client-side language that runs programs on a user's computer.
2) Core JavaScript concepts are explained such as objects, properties, methods, and how to reference browser and document objects.
3) Techniques for writing JavaScript programs are covered like adding comments, writing commands, debugging code, and working with variables.
This document discusses various methods for adding multimedia like audio and video to webpages. It covers HTML5 audio and video elements, supported file formats and codecs, adding captions and subtitles, applying CSS styles, embedding content from sites like YouTube, and using plugins as fallback options. The goal is to understand how to enhance a website with rich multimedia content in an accessible way across different browsers.
This document discusses designing web forms in HTML. It covers the basics of forms, including common form controls like text boxes, radio buttons, checkboxes, dropdown lists and more. It also discusses how to lay out forms, add labels and default values, and how forms interact with web servers. The goal is to explore the key elements for creating effective and functional web forms.
This document discusses using tables in HTML and CSS. It covers how to structure tables with <table>, <tr>, <th>, and <td> tags, style tables with CSS including borders and captions, work with rows and columns including grouping and spanning, and make tables responsive. The goal is to teach how to effectively organize and present information using tables and make those tables readable on different devices.
This document discusses responsive design and flexbox layouts for mobile web design. It covers creating media queries to apply different styles based on screen size, introducing the viewport and its relationship to device width, creating a responsive pulldown menu with CSS, and defining flexbox properties like flex-direction, flex-basis, flex-grow, and flex-shrink to create flexible layouts. The objectives are to make a website render well on devices of various sizes using these responsive design and flexbox techniques.
This document provides an overview of techniques for applying graphical effects to elements using CSS, including:
- Creating figure boxes and adding background images, borders, rounded corners, and gradients.
- Applying transformations, shadows, filters and semi-transparency to elements.
- Introducing 3D transformations and perspective.
- The document contains examples and explanations of CSS properties for each graphical effect.
This document discusses various page layout techniques in CSS including floats, grids, and positioning. It begins by explaining the objectives of creating a reset style sheet, exploring page layout designs, and various positioning techniques. It then covers creating floats, clearing floats, and preventing container collapse. The document ends by discussing grid-based layouts including setting up grids, fixed and fluid grids, and frameworks to support grid layouts.
This document discusses various CSS concepts including style sheets, selectors, inheritance, and properties for styling text, colors, and fonts. It covers the different types of style sheets like external, embedded, and inline styles. Contextual and attribute selectors are explained. Methods for applying colors like RGB, hex codes, and HSL are provided. The use of web fonts with the @font-face rule is also summarized.
The document discusses the objectives and structure of an HTML5 tutorial, including exploring the history of the web, creating the structure of an HTML document, inserting elements and attributes, and linking to other resources. It covers the basics of HTML5 such as the document type declaration, element tags, attributes, comments, and different types of elements like headings, paragraphs, images, and links.
An integer overflow occurs when the result of an arithmetic operation exceeds the maximum size of the integer type used to store it. This causes the value to wrap around and can lead to unexpected results. For example, adding 1 to the maximum 8-bit signed integer value of 127 would result in -128 instead of 128. Integer overflows can be exploited by attackers and cause issues like buffer overflows. Developers should choose appropriate integer types that can store all possible values and check for overflow conditions.
This document provides an overview of software testing fundamentals. It discusses why testing is necessary due to human errors that can lead to defects. It then defines software testing as a process used to evaluate a product against requirements and design specifications through execution of tests to detect defects. The document outlines the general test process, including test planning, analysis and design, implementation and execution, evaluating results against exit criteria, and closing testing activities.
The document discusses risk mitigation strategies for network security. It covers assessing threats through formal threat assessments that examine the likelihood and seriousness of potential threats. Risk assessments involve testing systems for vulnerabilities, managing changes to systems, auditing user privileges, and planning for incident response. The document outlines approaches to calculating risk both qualitatively and quantitatively by evaluating the likelihood and potential impact of risks based on historical data from sources like police, insurance companies, and computer incident monitoring organizations. Effective risk mitigation involves knowing potential threats, assessing related risks, and implementing strategies to reduce vulnerabilities and consequences.
The document discusses business continuity, which involves maintaining business operations after disruptive events through business continuity planning, business impact analysis, and disaster recovery planning. It describes business continuity planning as identifying threats, creating preventative and recovery procedures, and testing them. A business impact analysis identifies critical business functions and systems to prioritize in the event of disruption. The disaster recovery plan focuses on restoring IT resources and systems in a documented, tested process following a disruptive event through alternative processing sites and data resynchronization.
The document discusses vulnerability assessment and data security. It explains that vulnerability assessment involves systematically evaluating an enterprise's security posture by identifying assets, evaluating threats, assessing vulnerabilities, analyzing risks, and mitigating risks. This includes inventorying and prioritizing assets, modeling potential threats, cataloging existing weaknesses, estimating the impact of risks, and determining how to address risks. A variety of tools can be used for vulnerability assessment, such as port scanners, vulnerability scanners, and protocol analyzers.
Strategies for Effective Upskilling is a presentation by Chinwendu Peace in a Your Skill Boost Masterclass organisation by the Excellence Foundation for South Sudan on 08th and 09th June 2024 from 1 PM to 3 PM on each day.
The simplified electron and muon model, Oscillating Spacetime: The Foundation...RitikBhardwaj56
Discover the Simplified Electron and Muon Model: A New Wave-Based Approach to Understanding Particles delves into a groundbreaking theory that presents electrons and muons as rotating soliton waves within oscillating spacetime. Geared towards students, researchers, and science buffs, this book breaks down complex ideas into simple explanations. It covers topics such as electron waves, temporal dynamics, and the implications of this model on particle physics. With clear illustrations and easy-to-follow explanations, readers will gain a new outlook on the universe's fundamental nature.
A review of the growth of the Israel Genealogy Research Association Database Collection for the last 12 months. Our collection is now passed the 3 million mark and still growing. See which archives have contributed the most. See the different types of records we have, and which years have had records added. You can also see what we have for the future.
বাংলাদেশের অর্থনৈতিক সমীক্ষা ২০২৪ [Bangladesh Economic Review 2024 Bangla.pdf] কম্পিউটার , ট্যাব ও স্মার্ট ফোন ভার্সন সহ সম্পূর্ণ বাংলা ই-বুক বা pdf বই " সুচিপত্র ...বুকমার্ক মেনু 🔖 ও হাইপার লিংক মেনু 📝👆 যুক্ত ..
আমাদের সবার জন্য খুব খুব গুরুত্বপূর্ণ একটি বই ..বিসিএস, ব্যাংক, ইউনিভার্সিটি ভর্তি ও যে কোন প্রতিযোগিতা মূলক পরীক্ষার জন্য এর খুব ইম্পরট্যান্ট একটি বিষয় ...তাছাড়া বাংলাদেশের সাম্প্রতিক যে কোন ডাটা বা তথ্য এই বইতে পাবেন ...
তাই একজন নাগরিক হিসাবে এই তথ্য গুলো আপনার জানা প্রয়োজন ...।
বিসিএস ও ব্যাংক এর লিখিত পরীক্ষা ...+এছাড়া মাধ্যমিক ও উচ্চমাধ্যমিকের স্টুডেন্টদের জন্য অনেক কাজে আসবে ...
This slide is special for master students (MIBS & MIFB) in UUM. Also useful for readers who are interested in the topic of contemporary Islamic banking.
How to Fix the Import Error in the Odoo 17Celine George
An import error occurs when a program fails to import a module or library, disrupting its execution. In languages like Python, this issue arises when the specified module cannot be found or accessed, hindering the program's functionality. Resolving import errors is crucial for maintaining smooth software operation and uninterrupted development processes.
This presentation includes basic of PCOS their pathology and treatment and also Ayurveda correlation of PCOS and Ayurvedic line of treatment mentioned in classics.
Walmart Business+ and Spark Good for Nonprofits.pdfTechSoup
"Learn about all the ways Walmart supports nonprofit organizations.
You will hear from Liz Willett, the Head of Nonprofits, and hear about what Walmart is doing to help nonprofits, including Walmart Business and Spark Good. Walmart Business+ is a new offer for nonprofits that offers discounts and also streamlines nonprofits order and expense tracking, saving time and money.
The webinar may also give some examples on how nonprofits can best leverage Walmart Business+.
The event will cover the following::
Walmart Business + (https://business.walmart.com/plus) is a new shopping experience for nonprofits, schools, and local business customers that connects an exclusive online shopping experience to stores. Benefits include free delivery and shipping, a 'Spend Analytics” feature, special discounts, deals and tax-exempt shopping.
Special TechSoup offer for a free 180 days membership, and up to $150 in discounts on eligible orders.
Spark Good (walmart.com/sparkgood) is a charitable platform that enables nonprofits to receive donations directly from customers and associates.
Answers about how you can do more with Walmart!"
Executive Directors Chat Leveraging AI for Diversity, Equity, and InclusionTechSoup
Let’s explore the intersection of technology and equity in the final session of our DEI series. Discover how AI tools, like ChatGPT, can be used to support and enhance your nonprofit's DEI initiatives. Participants will gain insights into practical AI applications and get tips for leveraging technology to advance their DEI goals.
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...PECB
Denis is a dynamic and results-driven Chief Information Officer (CIO) with a distinguished career spanning information systems analysis and technical project management. With a proven track record of spearheading the design and delivery of cutting-edge Information Management solutions, he has consistently elevated business operations, streamlined reporting functions, and maximized process efficiency.
Certified as an ISO/IEC 27001: Information Security Management Systems (ISMS) Lead Implementer, Data Protection Officer, and Cyber Risks Analyst, Denis brings a heightened focus on data security, privacy, and cyber resilience to every endeavor.
His expertise extends across a diverse spectrum of reporting, database, and web development applications, underpinned by an exceptional grasp of data storage and virtualization technologies. His proficiency in application testing, database administration, and data cleansing ensures seamless execution of complex projects.
What sets Denis apart is his comprehensive understanding of Business and Systems Analysis technologies, honed through involvement in all phases of the Software Development Lifecycle (SDLC). From meticulous requirements gathering to precise analysis, innovative design, rigorous development, thorough testing, and successful implementation, he has consistently delivered exceptional results.
Throughout his career, he has taken on multifaceted roles, from leading technical project management teams to owning solutions that drive operational excellence. His conscientious and proactive approach is unwavering, whether he is working independently or collaboratively within a team. His ability to connect with colleagues on a personal level underscores his commitment to fostering a harmonious and productive workplace environment.
Date: May 29, 2024
Tags: Information Security, ISO/IEC 27001, ISO/IEC 42001, Artificial Intelligence, GDPR
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Main Java[All of the Base Concepts}.docxadhitya5119
This is part 1 of my Java Learning Journey. This Contains Custom methods, classes, constructors, packages, multithreading , try- catch block, finally block and more.
2. Guide to Operating Systems, 4th ed. 2
Objectives
2
• List the basic functions common to all file systems
• Explain the file systems used by Windows XP,
Windows Server 2003, Windows Vista, Windows
Server 2008, and Windows 7 (FAT16, FAT32,
FAT64, and NTFS)
• Discuss the file systems used by UNIX and Linux
systems, including ufs and ext
• Explain the Mac OS X Extended (HFS+) file system
including new features added in Mac OS X version
10.6 Leopard
3. Guide to Operating Systems, 4th ed. 3
Understanding the File System Functions
• All information stored on a computer’s hard disk is
managed, stored, and retrieved through a file
system
– The file system allocates locations on a disk for storage and it
keeps a record of where specific information is kept
– Some file systems also implement recovery procedures when a
disk area is damaged or when the OS goes down
• The overall purpose of a file system is to create a
structure for filing data
• A file is a set of data that is grouped in some logical
manner, assigned a name, and stored on the disk
4. Guide to Operating Systems, 4th ed. 4
Understanding File System Functions
• File systems used by operating systems perform
the following general tasks:
– Partition and format disks to store and retrieve information
– Enable files to be organized through directories and folders
– Establish file-naming conventions
– Provide utilities to maintain and manage the file system and
storage media
– Provide for file and data integrity
– Enable error recovery or prevention
– Secure the information in files
5. Guide to Operating Systems, 4th ed. 5
Understanding File System Functions
• Directory or folder – organizational structure that
contains files and may additionally contain
subdirectories (or subfolders)
• Directories may store the following information
– Date and time the directory or file was created
– Date and time the directory or file was last modified
– Date and time when the directory or file was last accessed
– Directory or file size
– Directory or file attributes, such as security information, or if the
directory or file was backed up
– If the information in a directory or file is compressed or
encrypted
6. Guide to Operating Systems, 4th ed. 6
Designing a Directory Structure
• A chaotic file structure:
– makes it difficult to run or remove programs
– Makes it difficult to determine the most current versions
– Makes users spend unproductive time looking for specific files
• Some users keep most of their files in the computer’s
primary level or root directory (root folder)
• Some programs use an automated setup that suggests
folders for new programs
– Example – creating new subfolders under the Program Files folder
• To avoid chaos, design the file and folder structure from
the start (especially on servers)
7. Guide to Operating Systems, 4th ed. 7
Designing a Directory Structure
• Consider following some general practices:
– Root folder should not be cluttered with files or too many
directories/folders
– Each software application should have its own folder/subfolder
– Similar information should be grouped (example: accounting
systems or office productivity software)
– Operating system files should be kept separate and protected
– Directories and folders should have names that clearly reflect
their purposes (a folder named “Shared” would contain
documents that can be shared by many users)
8. Guide to Operating Systems, 4th ed. 8
Designing a Directory Structure
Sample folder structure for a Windows-based system
9. Guide to Operating Systems, 4th ed. 9
Disk Storage Basics
• Hard disks arrive from manufacturer with low-level
formatting
– A low-level format is a software process that marks the
location of disk tracks and sectors
– Tracks are like several circles around a disk and each track is
divided into sections of equal size called sectors
11. Guide to Operating Systems, 4th ed. 11
Block Allocation
• Block allocation – divides the disk into logical blocks
called clusters, which correlate to sectors, heads, and
tracks on the disk
– Keeps track of where specific files are stored on the disk
• Cylinders – tracks that line up on each platter from
top to bottom and are all read at the same time
• Data regarding block allocation is stored using one
of two techniques:
– File allocation table (FAT)
– New Technology File System (NTFS) and Unix/Linux file systems
– uses various locations on the disk to store a special type of file
that is used for directory and file allocation information
12. Guide to Operating Systems, 4th ed. 12
Partitions
• Partitioning – process of blocking a group of
tracks and sectors to be used by a particular file
system, such as FAT or NTFS
• After partitioning, the disk must be high-level
formatted in order for the OS to store files
• It might be necessary for a disk to have more than
one file system
– Will require a partition for each file system
– Example: To allow the installation of Red Hat Enterprise Linux
and Windows 7 on the same computer
13. Guide to Operating Systems, 4th ed. 13
Partitions
• Logical drives – creating multiple logical volumes
on a single disk and assigning drive letters to each
volume
• When a partition is created, information about that
partition is stored in a special area of the disk
known as the partition table (in MS-DOS, Mac
OS, and Windows) and disk label (in UNIX/Linux)
• Another piece of disk that is reserved is known as
the boot block in UNIX/Linux and Mac OS X, or
the Master Boot Record (MBR) in MS-DOS and
Windows.
14. Partitions
• In Windows, the MBR consists of four elements:
– The boot program – examines the partition table to determine
which partition to boot from
– The disk signature – stores information about the disk and is
used by management software such as the Windows registry
– The partition table for the active partition
– The end-of-MBR marker – where the MBR ends
• Not all operating systems support partitions in the
same way
• Each operating system uses specific utilities to
create partitions
Guide to Operating Systems, 4th ed. 14
15. Guide to Operating Systems, 4th ed. 15
Formatting
• Formatting – the process of placing the file system
on the partition
– Necessary in order to install an operating system
• After the OS is installed, a disk management tool
can be used to partition and format additional free
space
• Can also use the format command from the
Command Prompt window
– The format command includes several switches (extra codes)
– To view a list of these switches, type format /?
16. Guide to Operating Systems, 4th ed. 16
Formatting
• When a file is stored to disk:
– Data is written to clusters on the disk
– Filename is stored in the folder, along with the number of the first
cluster the data is stored in
– When the OS fills the first cluster, data is written to the next free
cluster and the FAT entry corresponding with the first cluster points to
the number of the second cluster used
– When the second cluster is full, the OS continues with the next free
cluster and the FAT entry for the second cluster points to the number
of the third cluster used, and so on…
– When a file is completely written to the disk, the FAT entry for the final
cluster is filled with all 1s (means end of file)
– This is commonly referred to as the linked-list method
17. Guide to Operating Systems, 4th ed. 17
Formatting
• Clusters are a fixed length
– When a files does not use all of the space in a cluster, the rest
of the cluster is unusable
– Unusable spots are marked in the FAT as bad clusters (never
used for file storage)
• Each partition stores and extra copy of the FAT
table in case the first copy gets damaged
• There is only one copy of the root directory on each
partition (see figure on the following slide)
• The FAT tables and root directory are at the
beginning of each partition and always at the same
location
19. Formatting
• Each FAT directory entry contains filename, file
change date and time, file size, and file attributes
• Attributes can indicate whether a file is set to:
– Read-only
– Archive (to be backed up the next time a backup is made)
– System
– Hidden
Guide to Operating Systems, 4th ed. 19
20. Guide to Operating Systems, 4th ed. 20
Windows File Systems
• Windows XP, Vista 7, Server 2003, and Server
2008 support three files systems:
– Extended FAT16
– FAT32
– NTFS
• These OSs also support file systems for DVD/CD-
ROM drives and USB devices (flash drives)
21. FAT16 and Extended FAT16
• Extended FAT16 evolved from FAT16 used in
earlier versions of MS-DOS and Windows
(3.x/95/98/Me)
• In extended FAT16:
– Maximum size of a volume is 4GB
– Maximum size of a file is 2GB
– Has been around for awhile and can be read by non-Windows
operating systems like UNIX/Linux
– Considered a stable file system
– Long filenames (LFNs) can be used
• Can contain up to 255 characters
• Not case sensitive
Guide to Operating Systems, 4th ed. 21
22. Guide to Operating Systems, 4th ed. 22
FAT32
• Support for FAT32 started with Windows 95
Release 2
• Designed to accommodate larger capacity disks
• FAT32:
– Root folder does not have to be at the beginning of a volume
– Can use disk space more efficiently than FAT16 (because it
uses smaller cluster sizes)
– Largest volume that can be formatted is 32 GB
– Maximum file size is 4 GB
– Offers fast response on small 1 or 2 GB partitions
23. Guide to Operating Systems, 4th ed. 23
FAT64
• FAT64 is also known as exFAT
• Proprietary file system introduced by Microsoft for
mobile personal storage
• Good choice for USB flash devices that may store
large files (such as pictures, videos, etc…)
• Available in Service Pack 1 for Windows Vista,
Windows 7, and Windows Server 2008, Mac OS X
Snow Leopard
• Support is available for Linux from a third party
24. Guide to Operating Systems, 4th ed. 24
NTFS
• NTFS – dominant Windows file system for all
Windows operating systems starting with Windows
2000
• Uses a Master File Table (MFT) instead of FAT
tables
• The MFT and related files take up about 1 MB of
disk space
• When a file is created, a record for that file is
added to the MFT
– Contains additional attributes such as security settings,
ownership, and permissions
25. Guide to Operating Systems, 4th ed. 25
NTFS
• The MFT record reflects the sequence of clusters
that a file uses
• It is possible to have multiple filenames that refer to
the same file
– A technique known as hard linking
– This feature is also available in UNIX/Linux file systems
• Windows Vista, Server 2008, and 7 use NTFS
version 6
• Windows XP and Server 2003 use NTFS version 5
• Windows NT 4.0 used NTFS 4
26. Guide to Operating Systems, 4th ed. 26
NTFS
• Basic features of NTFS:
– Long filenames
– Built-in security features
– Better file compression than FAT
– Ability to use larger disks and files than FAT
– File activity tracking for better recovery and stability than FAT
– Portable Operating System Interface for Unix (POSIX)
support
– Volume striping and volume extensions
– Less disk fragmentation than FAT
27. Guide to Operating Systems, 4th ed. 27
NTFS
• NTFS is equipped with security features that meet
the US government’s C2 security specifications
– Refers to high-level, “top-secret” standards for data protection,
system auditing, and system access
• Examples:
– System files can be protected so only the server administrator
has access
– A folder of databases can be protected with read access, but
no access to change data
– Public folder can give users in a designated group access to
read and update files, but not to delete files
28. Guide to Operating Systems, 4th ed. 28
NTFS
• Some files can be compressed by more than 40%,
saving disk storage for other storage needs
• NTFS has the ability to keep a log or journal of file
system activity (called journaling)
– Makes it possible for files to be restored in the event of a power
failure
• NTFS supports volume striping
– Process that equally divides the contents of each file across two or
more volumes to extend disk life, enable fault tolerance, and
balance disk load for better performance
• NTFS has hot fix capabilities
– If a bad disk area is detected, automatically copies the information
to another disk area that is not damaged
29. Guide to Operating Systems, 4th ed. 29
NTFS
• In addition to NTFS 4 features, NTFS 5 adds
several new features:
– Ability to encrypt files
– No system reboot required after creating an extended volume
– Ability to reduce drive designations
– Indexing for fast access
– Ability to retain shortcuts and other file information when files
and folders are placed on other volumes
– Ability to establish disk quotas (to control how much disk space
users can occupy)
30. NTFS
• NTFS 6 (latest version) adds several new features:
– Transactional NTFS – used to perform operations in
transactions (all at once or not all)
– Partition resizing – allows administrator to expand or shrink
partitions
– Self-healing – the chkdsk utility runs in the background to
correct hard disk problems (instead of having to take the
volume down to run it)
Guide to Operating Systems, 4th ed. 30
31. NTFS
• The chkdsk utility can detect and fix an extensive
set of file system problems in FAT and NTFS
system
– This utility is available in all versions of Windows starting with
Windows 2000
– The most common problems found are files with 0 sizes,
caused when a file is not properly closed or chains of clusters
that have no directory entries
• Windows 2000 and later versions have a built-in
disk defragmenting tool
– Rearranges data on the disk in a continuous fashion, ridding
the disk of scattered open clusters
Guide to Operating Systems, 4th ed. 31
33. CDFS and UDF
• Windows versions after Windows 2000 recognize
some additional file systems used by peripheral
storage technologies
• CD-ROM File System (CDFS) – supported so that
OSs can read and write files to DVD/CD-ROM
drives
• Universal Disk Format (UDF) – also used on
DVD/CD-ROMs, which are used for huge file
storage to accommodate movies and games
Guide to Operating Systems, 4th ed. 33
34. The UNIX File System
• There are many different file systems that can be
used with UNIX
– Some file systems are more “native” to specific UNIX operating
systems than others
• Most versions of UNIX and Linux support the UNIX
file system (ufs), which is the original native UNIX
file system
– ufs is a hierarchical file system that is expandable, supports
large storage, provides excellent security, and is reliable
– Many qualities of NTFS are modeled after ufs (journaling and
hot fixes)
Guide to Operating Systems, 4th ed. 34
35. The UNIX File System
• In Linux, the native file system is called the
extended file system (ext or ext fs)
• ext is modeled after ufs and enables the use of the
full range of built-in Linux commands, file
manipulation, and security
• The first ext version had bugs
– ext2 – reliable file system that handles large disk storage
– ext3 – added journaling capabilities
– ext4 – supports file sizes up to 16 TB
Guide to Operating Systems, 4th ed. 35
36. The UNIX File System
• Both ufs and ext use the same structure
– Built on the concept of information nodes (or inodes)
– Each file has an inode and is identified by an inode number
– An inode contains general information about that file such as:
• User and group ownership, permissions, size and type of file, date
the file was created, and the date the file was last modified and
read
– Each disk is divided into logical blocks
• The superblock contains information about the layout of blocks,
sectors, and cylinder groups on the file system
– The inode for a file contains a pointer (number) that tells the
OS where to find a file on the hard disk (based on logical
blocks)
– Inode 0 contains the root of the folder structure and is the
jumping off point for all other inodesGuide to Operating Systems, 4th ed. 36
37. The UNIX File System
• A UNIX/Linux system can have many file systems
– Mounts file systems as a sub file system of the root file system
– All file systems are referred to by a path
– The path starts out with / (/ indicates the main root directory of
the file system)
– See Figure 4-14 on the next slide for examples
• Directories in the file system contain a series of
filenames
– UNIX/Linux allows the use of long filenames, which may
include any character that can be represented by ASCII
Guide to Operating Systems, 4th ed. 37
38. The UNIX File System
UNIX/Linux file system path entries
Guide to Operating Systems, 4th ed. 38
39. The UNIX File System
• Disks are referenced by a special inode called a
device
• There are two types of devices:
– Raw device – has no logical division in blocks
– Block device – does have logical division in blocks
• Devices are normally kept in the /dev or /devices
directory
• Symbolic link – used to link a directory entry to a
file that is on a different partition
– Merely a pointer to a file
Guide to Operating Systems, 4th ed. 39
40. The UNIX File System
• You must first partition a disk to use the UNIX/Linux file
system
• The command to partition the disk differs slightly
– Most UNIX systems use either fdisk or format
– Typing man fdisk or man format at the command prompt gives you an
overview of available commands
Guide to Operating Systems, 4th ed. 40
41. The UNIX File System
• Once a partition is made, a file system can be
created
– You must know the device name of the partition on which you
wish to create a file system
– Type newfs, followed by the name of the device
– The newfs command is not available in all versions of Linux
• Use the mkfs command instead
Guide to Operating Systems, 4th ed. 41
42. The UNIX File System
• When a file is saved to disk, the system first stores
part of the data to memory until it has time to write
to disk
– If computer is shut down prior to data being written to disk, you
can end up with a damaged file system
– UNIX/Linux systems should always be shut down using proper
shutdown commands
– You can manually force a write of all data in memory by using
the sync command
• Another utility is known as fsck
– Verifies the integrity of the superblock, the inodes, all cluster
groups, and all directory entries
Guide to Operating Systems, 4th ed. 42
43. The UNIX File System
UNIX/Linux file system commands
Guide to Operating Systems, 4th ed. 43
44. The Macintosh File System
• The original Macintosh Filing System (MFS) of
1984 was limited
– Kept track of 128 documents, applications or folders
– Reasonable limit when the only storage device was a 400 KB
floppy disk drive
• In 1986, Apple created Hierarchical Filing System
(HFS)
– Divided a volume (disk partition) into allocation blocks – similar
to clusters on PCs
• In 1998, Apple released Mac OS 8.1 with a new file
system called Hierarchical Filing System Extended
Format (HFS+)
Guide to Operating Systems, 4th ed. 44
45. The Macintosh File System
• In Mac OS X version 3.0, Mac OS Extended
(HFS+) includes new features:
– A case-sensitive format to make the file system more
compatible with other UNIX/Linux systems
– Journaling
– Ability to store up to 16 TB of data
• The first two sectors of a Mac-formatted disk are:
– Boot sectors, or boot blocks
– Volume information block – contains catalog b-tree
• Catalog b-tree is a list of all files on the volume and keeps track of
a file’s name, location in the folder structure, and its physical
location
Guide to Operating Systems, 4th ed. 45
46. The Macintosh File System
• Macintoshes can read and write to disks from other
operating systems
• Mac OS has always supported what might be
called medium filenames (up to 31 characters)
– Any character may be used in a filename except the colon (:)
– Reason for this: Macintosh paths are written as colon-
separated entities such as:
• Hard Drive:System Folder:Preferences:Finder Prefs
• Mac uses type codes and creator codes instead of
filename extensions as in Windows
– Files created with Apple’s SimpleText editor have a type code
of APPL and a creator code of ttxt
Guide to Operating Systems, 4th ed. 46
47. The Macintosh File System
• Macintosh files can contain two parts, or forks:
– Data fork – contains frequently changing information (such as
word processing data)
– Resource fork – contains information that is fixed (such as a
program’s icons, menu resources, and splash screens)
• Because Mac files have type and creator codes
and two forks can create problems when storing
files on non-Macintosh servers
– MacBinary – format which joins the two forks into one, and
safely stores the type and creator codes and finder flags
Guide to Operating Systems, 4th ed. 47
48. The Macintosh File System
• Apple’s equivalent to a Windows shortcut is the
alias (introduced in System 7.0 in 1991)
– The system-level Alias Manager keeps track of the original
– The word “alias” is tacked onto the filename when the alias is
created and the filename is italicized
• Mac OS X comes with two disk utilities:
– Disk Utility – manages disk drives
– Disk First Aid – repairs disk problems
• Mac OS X also comes with a utility (Sherlock) that
searches disks for filenames and text within files
– Spotlight replaced Sherlock in Mac OS X 10.4 Tiger
Guide to Operating Systems, 4th ed. 48
49. The Macintosh File System
A Spotlight search in Mac OS X Snow Leopard
Guide to Operating Systems, 4th ed. 49
50. The Macintosh File System
• When a Mac is not shut down properly a disk
integrity check will automatically run at the next
startup
• Macs will boot from a DVD/CD-ROM or various
SCSI devices
– To boot from a DVD/CD-ROM, press the “C” key while booting
up
– Pressing the Shift-Option-Delete-Apple (SODA) keys while
booting will bypass the internal hard drive and boot from the
next drive in a SCSI chain
Guide to Operating Systems, 4th ed. 50
51. Chapter Summary
• For the user, files are the “bread and butter” of an operating
system. Besides containing the operating system kernel, files hold
documents and programs on which users rely.
• Files are made possible by a file system that enables them to be
created, written, managed, and stored on disk media. All OSs must
have a file system that provides a file-naming convention, a way to
store files, and a means to partition and format disks.
• Besides creating and modifying files, the file system also should
offer the ability to defragment files, compress file contents, ensure
file and data integrity, secure files, and control removable storage
media.
• The main file systems used in Windows since Windows 2000 are
extended FAT16, FAT32, and NTFS.
Guide to Operating Systems, 4th ed. 51
52. Chapter Summary
• In FAT16 and FAT32, the file system creates a file allocation
table to store information about files.
• FAT32 is more robust than FAT16, providing for the use of
more clusters and larger partitions.
• FAT64 (exFAT) is mainly used for personal mobile storage
devices like flash drives.
• NTFS is the native file system for Windows 2000 and after
with the advantage of better security, larger disk and file
sizes, better management tools, and greater stability than
FAT16 and FAT32.
• chkdsk is an important disk verification and repair utility that
works for FAT16, FAT32, and NTFS.
Guide to Operating Systems, 4th ed. 52
53. Chapter Summary
• UNIX and Linux support many support many different file
systems but typically employ ufs or ext
• ufs and ext use information nodes (inodes) to organize
information about files.
• Different varieties of UNIX/Linux use different file system
utilities, such as fdisk and format to partition and format
disks. The fsck (file system checker) utility is used to verify
the integrity of UNIX/Linux file systems.
• Mac OS X uses Mac OS Extended (HFS+) file system, which
is an enhancement of HFS and was introduced in 1998 with
Mac OS 8.1.
Guide to Operating Systems, 4th ed. 53
54. Chapter Summary
• Two important Mac OS X disk tools include Disk Utility and
Disk First Aid.
• Table 4-8 shows the disk management tools you have
learned about in the chapter. Of these tools, the Mac OS X
tool might be the most “one-stop,” because you can use it to
configure, repair, and manage disks.
Guide to Operating Systems, 4th ed. 54