Differentiate Fat Fat32 And Ntfs Information Technology Essay

In this term paper I have introduced the FAT, FAT32 and NTFS different file system . It includes features of FAT 32 and NTFS. At last there is comparison between FAT32 and NTFS.

INTRODUCTION:-

FAT:-

FAT means file allocation table used by the operating system for locating files on a disk, a file can be divided into many parts due to fragmentation that is scattered around the disk. The File Allocation Table keeps track of group of all these pieces. File Allocation Table is a group of addresses that reach in the form of a table to see which cluster is coming next, when a file is accessed or a directory is scanned.

In DOS, FAT is stored after the boot sector. The older versions of FAT for Windows 95 and earlier is called FAT16, and for new versions of Windows 98 and 95 is called FAT32.

Terminology:-

FAT: stands for File Allocation Tables, a data structure that is found in all FAT volumes.

FAT1: It is the first thing to see in FAT.

FAT2: The 1st copy that is used by the FAT.

FAT12: File Allocation Table file systems uses 12-bits clustered addresses.

FAT16: File Allocation Table file systems uses 16-bit clustered address.

FAT32: File Allocation Table file systems uses 32-bit clustered address..

FATxx: File system that use File Allocation Table and all that is used by FAT.

VFAT: It is the 32-bit code used for operation the file system in Win9x Graphical User Interface mode.

Cluster: It is the Single unit for storage of data on the FATxx file systems.

Sector: It is the unit of storage devices at the physical level of disk.

Physical sector address: It refers to Sector addresses at absolute physical hardware terms.

CHS sector address mode: As above, expressed in Cylinder, Head etc

Logical sector address: It is a Sector address which is relative to the FATxx volume.

Folder: It is a collection of items named as seen with the help of Windows Explorer.

File Folder: It resembles the same as windows call it “directory”.

Directory: It is a data structure that lists file and directory.

Directory entry: It generally points to a file or directory, and contains the information about it.

Attributes: It refers to the collection of bits in a directory entries that mention it.

File Allocation Table is the entries list which is mapped to each and every cluster at the time of partition. The partition is further divided up into identically sized clusters, small block of space. The size of cluster varies depending on the type of FAT file

Each entry contains records of one of five things:

the cluster numbering of the coming cluster in a sequence

a special end of chain cluster (EOC) entry that points to the end of a chain

a special entry for marking a bad clustering

a special entry for marking a reserved cluster

a zero to note that the cluster on which we are working is unused

FAT entry values:

FAT12

FAT16

FAT32

Description

0x000

0x0000

0x0000000

Free Cluster

0x001

0x0001

0x0000001

Reserved value; do not use

0x002-0xFEF

0x0002-0xFFEF

0x0000002-0x0FFFFEF

Used cluster; value points to next cluster

0xFF0-0xFF6

0xFFF0-0xFFF6

0x0FFFFF0-0x0FFFFF6

Reserved values; do not use.

0xFF7

0xFFF7

0x0FFFFF7

Bad sector in cluster or reserved cluster

0xFF8-0xFFF

0xFFF8-0xFFFF

0x0FFFFF8-0x0FFFFFF

Last cluster in file (EOC)

File System Structure:-

The File Allocation Table volume has been divided into different four areas:

The boot record:- It is the first and the starting sector of a FAT12 or FAT16 volume. It gives us the definition of the volume that we are using, as well as for the other remaining three areas. If the volume is made bootable, then the very first record will also contains the code required to enter the file system and for the purpose to boot the Operating System.

The File Allocation Tables:- It is a address that can be reached as a lookup table to check which cluster comes next, when a file is load or scanning a directory. Because the File Allocation Table is such a important data structure, there are typically two copies (i.e. FAT1 and FAT2) so that corruption of the File Allocation Table i.e. FAT can be detected and intelligently repaired.

The root directory:- It fixed in length and is always located at the starting of the volume (after the FAT) in FAT12 and FAT16 volumes, but FAT32 treats the root directory as just another cluster chain in the data area. However, even in FAT32 volume, the root directory will automatically follow immediately after the two FATs.

The data area:- It fills the remaining part of the volume, and is divided into many clusters; it is only here that the file data is stored. Subdirectories are the very special files with a structure that can be easily understood by the file system, and is marked as directories rather than files by setting the “directory” attribute bit on the directory entry that always points to it.

FAT32:-

The FAT32 file system is that one which was originally introduced in Windows 95 Service Pack 2, which is really just an extension of the original FAT16 file system that provides a much larger number of clusters per partition as compared to others. As such, it helps greatly in improving the overall disk utilization when it compared to a FAT16 file system. However, FAT32 shares all of the other limitations of FAT16, and adds an vital additional limitation-many operating systems that recognize FAT16 will not work with FAT32-most probably Windows NT, but also Linux, UNIX etc as well. Now this is not the problem if we running FAT32 on a Windows XP computer and sharing our drive out to other computers on our network-we don’t need to know (and generally don’t really care) what our underlying file system is.

Features:-

FAT32 supports drives up to 2 terabytes in size.

FAT32 uses space more efficiently as compared to others.

FAT32 is more robust. FAT32 can be used to relocate the root folder and use the backup copy of the file allocation table instead of default copy.

FAT32 is more flexible as compared to others. The root folder on a FAT32 drive is a cluster chain, so it can be used to locate anywhere on the drive. The previous flaws on the number of root folder entries no longer exist. Further, file allocation table monitoring can be disabled, allowing a copy of the file allocation table other than the first one to be active.

NTFS:-

NTFS is define as New Technology File System .it is a file system that was introduced by Microsoft in 1993 with Windows NT. It supports hard drive sizes up to 256TB.

It is the primary file system used in Microsoft Windows 7, Windows Vista, Windows XP, Windows 2000 and Windows NT operating systems. The Windows Server also primarily uses NTFS.

NTFS has several advantages over FAT and HPFS (High Performance File System) such as improved support for metadata and the use of advanced data structures to improve performance, reliability, and disk space utilization.

The File Allocation Table (FAT) file system was the primary file system in Microsoft older operating systems but it is still supported today along with NTFS. It is more powerful and offers security advantages not found in the other file systems. There are normally three different file systems available in Windows XP: FAT16 i.e.short for File Allocation Table, FAT32, and NTFS, short for NT File System.

The NTFS file system is generally not supportable with other OS installed on the same computer, nor is it available when we have booted a computer from a floppy disk.

Advantages of NTFS:-

It introduced the first version of Windows NT, which is totally different file system from FAT. It provides for highly increased security.

If we have already upgraded to Windows XP and did not do the conversion then, it is not a problem. You can convert FAT16 or FAT32 volumes to NTFS at any point.

NTFS Security Features:-

. File compression

Encrypting File System (EFS)

NTFS Security and Permissions

Hard links and short filenames

COMPARISON :-

In FAT 32 operating system that are used is Windows 98 & XP whereas operating system used in NTFS is Windows XP.

These are much file system for hard drives.  Each has it’s own pro’s and con’s. But FAT32 is preferred because it is easy to read and write to with a boot floppy.  Windows XP comes with a conversion utility for FAT32 to NTFS called convert.exe.  Only the operating system decide whether a partition’s file system can be read or not .

There are no security features in built-in FAT which was designed in single user era whereas NTFS has many security features built into it making it the a file system for multi user operating system.

BibliographY:-.

Operating system concepts by Gill n Smith

A fundamental aaproach to Operating System by Jain and Iyer