FACTOID # 145: Three of the top ten countries for GDP per capita are island nations: Bermuda, Cayman Islands, and Iceland.
 
 Home   Encyclopedia   Statistics   Countries A-Z   Flags   Maps   Education   Forum   FAQ   About 
 
 
 
WHAT'S NEW
RECENT ARTICLES
More Recent Articles »
 

SEARCH ALL

FACTS & STATISTICS    Advanced view

Search encyclopedia, statistics and forums:

 

 

(* = Graphable)

 

 


Encyclopedia > 60056
NTFS
Developer Microsoft
Full name New Technology File System
Introduced July 1993 (Windows NT 3.1)
Partition identifier 0x07 (MBR)
EBD0A0A2-B9E5-4433-87C0-68B6B72699C7 (GPT)
Structures
Directory contents B+ tree
File allocation Bitmap/Extents
Bad blocks Bitmap/Extents
Limits
Max file size 16 TiB with current implementation

(16 EiB architecturally) A software developer is a person who is concerned with one or more facets of the software development process, a somewhat broader scope of computer programming or a specialty of project managing. ... Microsoft Corporation, (NASDAQ: MSFT, HKSE: 4338) is a multinational computer technology corporation with global annual revenue of US$44. ... 1993 is a common year starting on Friday of the Gregorian calendar and marked the Beginning of the International Decade to Combat Racism and Racial Discrimination (1993-2003). ... Windows NT is a family of operating systems produced by Microsoft, the first version of which was released in July 1993. ... In computer engineering, hard disk drive partitioning is the creation of logical divisions upon a hard disk that allows one to apply operating system-specific logical formatting. ... A master boot record (MBR) is the first sector (sector zero) of a data storage device such as a hard disk. ... This article or section may be confusing or unclear for some readers, and should be edited to rectify this. ... GUID Partition Table (GPT) is a standard for the layout of the partition table on a physical hard disk. ... A simple B+ tree example linking the keys 1-7 to data values d1-d7. ... A tebibyte is a unit of information or computer storage, commonly abbreviated TiB. 1 tebibyte = 240 bytes = 1,099,511,627,776 bytes The tebibyte is closely related to the terabyte, which can either be a synonym for tebibyte, or refer to 1012 bytes = 1,000,000,000,000 bytes... An exbibyte (a contraction of exa binary byte) is a unit of information or computer storage, abbreviated EiB. 1 exbibyte = 260 bytes = 1,152,921,504,606,846,976 bytes = 1,024 pebibytes The exbibyte is closely related to the exabyte, which can either be a synonym for exbibyte, or...

Max number of files 4,294,967,295 (232-1)
Max filename size 255 characters
Max volume size 256 TiB with current implementation (16 EiB architecturally)
Allowed characters in filenames any character except '0' (NULL) and '/'[1]

The Win32 Subsystem also excludes the use of  : * ? " < > and pipe A tebibyte is a unit of information or computer storage, commonly abbreviated TiB. 1 tebibyte = 240 bytes = 1,099,511,627,776 bytes The tebibyte is closely related to the terabyte, which can either be a synonym for tebibyte, or refer to 1012 bytes = 1,000,000,000,000 bytes... An exbibyte (a contraction of exa binary byte) is a unit of information or computer storage, abbreviated EiB. 1 exbibyte = 260 bytes = 1,152,921,504,606,846,976 bytes = 1,024 pebibytes The exbibyte is closely related to the exabyte, which can either be a synonym for exbibyte, or...

Features
Dates recorded Creation, modification, POSIX change, access
Date range 1 January 1601 - 28 May 60056
Forks Yes
Attributes Read-only, hidden, system, archive
File system permissions ACLs
Transparent compression Per-file, LZ77 (Windows NT 3.51 onward)
Transparent encryption Per-file,
DESX (Windows 2000 onward),
Triple DES (Windows XP onward),
AES (Windows XP Service Pack 1, Windows Server 2003 onward)
Supported operating systems Windows NT family (Windows NT 3.1 to Windows NT 4.0, Windows 2000, Windows XP, Windows Server 2003, Windows Vista)

NTFS or New Technology File System[2] is the standard file system of Windows NT and its descendants Windows 2000, Windows XP, Windows Server 2003, and Windows Vista. January 1 is the first day of the calendar year in both the Julian and Gregorian calendars. ... Events February 8 - Robert Devereux, 2nd Earl of Essex, rebels against Elizabeth I of England - revolt is quickly crushed February 25 - Robert Devereux beheaded Jesuit Matteo Ricci arrives in China Bad harvest in Russia due to rainy summer Dutch troops drive Portuguese from Málaga Battle of Kinsale, Ireland Births... May 28 is the 148th day of the year in the Gregorian calendar (149th in leap years). ... In computing, a fork is additional data associated with a file system object. ... Most modern file systems have methods of administering permissions or access rights to specific users and groups of users. ... The access control list (ACL) is a concept in computer security used to enforce privilege separation. ... LZ77 and LZ78 are the names for the two lossless data compression algorithms published in papers by Abraham Lempel and Jacob Ziv in 1977 and 1978. ... Windows NT is a family of operating systems produced by Microsoft, the first version of which was released in July 1993. ... Filesystem-level encryption, is a form of disk encryption where individual files or directories are encrypted by the file system, in contrast to full disk encryption where the entire partition or disk, where the file system resides, is encrypted. ... In cryptography, DES-X (or DESX) is a variant on the DES (Data Encryption Standard) block cipher intended to increase the complexity of a brute force attack using a technique called key whitening. ... Windows 2000 (also referred to as Win2K) is a preemptible, interruptible, graphical and business-oriented operating system that was designed to work with either uniprocessor or symmetric multi-processor 32-bit Intel x86 computers. ... In cryptography, Triple DES (also 3DES) is a block cipher formed from the Data Encryption Standard (DES) cipher. ... Windows XP is a line of proprietary operating systems developed by Microsoft for use on general-purpose computer systems, including home and business desktops, notebook computers, and media centers. ... In cryptography, the Advanced Encryption Standard (AES), also known as Rijndael, is a block cipher adopted as an encryption standard by the U.S. government. ... Windows Server 2003 is a server operating system produced by Microsoft. ... An operating system (OS) is a set of computer programs that manage the hardware and software resources of a computer. ... Windows NT is a family of operating systems produced by Microsoft, the first version of which was released in July 1993. ... Windows NT 3. ... Windows NT 4. ... Windows 2000 (also referred to as Win2K) is a preemptible, interruptible, graphical and business-oriented operating system that was designed to work with either uniprocessor or symmetric multi-processor 32-bit Intel x86 computers. ... Windows XP is a line of proprietary operating systems developed by Microsoft for use on general-purpose computer systems, including home and business desktops, notebook computers, and media centers. ... Windows Server 2003 is a server operating system produced by Microsoft. ... Windows Vista is the latest release of Microsoft Windows, a line of graphical operating systems used on personal computers, including home and business desktops, notebook computers, Tablet PCs, and media centers. ... In computing, a file system (often also written as filesystem) is a method for storing and organizing computer files and the data they contain to make it easy to find and access them. ... Windows NT is a family of operating systems produced by Microsoft, the first version of which was released in July 1993. ... Windows 2000 (also referred to as Win2K) is a preemptible, interruptible, graphical and business-oriented operating system that was designed to work with either uniprocessor or symmetric multi-processor 32-bit Intel x86 computers. ... Windows XP is a line of proprietary operating systems developed by Microsoft for use on general-purpose computer systems, including home and business desktops, notebook computers, and media centers. ... Windows Server 2003 is a server operating system produced by Microsoft. ... Windows Vista is the latest release of Microsoft Windows, a line of graphical operating systems used on personal computers, including home and business desktops, notebook computers, Tablet PCs, and media centers. ...


NTFS replaced Microsoft's previous FAT file system, used in MS-DOS and early versions of Windows. NTFS has several improvements over FAT such as improved support for metadata and the use of advanced data structures to improve performance, reliability, and disk space utilization plus additional extensions such as security access control lists and file system journaling. The exact specification is a trade secret, although (since NTFS v3.00) it can be licensed commercially from Microsoft through their Intellectual Property Licensing program. Microsoft Corporation, (NASDAQ: MSFT, HKSE: 4338) is a multinational computer technology corporation with global annual revenue of US$44. ... File Allocation Table (FAT) is a partially patented file system developed by Microsoft for MS-DOS and was the primary file system for consumer versions of Microsoft Windows up to and including Windows Me. ... Microsofts disk operating system, MS-DOS, was Microsofts implementation of DOS, which was the first popular operating system for the IBM PC, and until recently, was widely used on the PC compatible platform. ... Metadata is data about data. ... The access control list (ACL) is a concept in computer security used to enforce privilege separation. ... A journaling (or journalling) file system is a file system that logs changes to a journal (usually a circular log in a specially-allocated area) before actually writing them to the main file system. ... A trade secret is a formula, practice, process, design, instrument, pattern, or compilation of information used by a business to obtain an advantage over competitors within the same industry or profession. ...


NTFS has five versions:

  • v1.0
  • v1.1
  • v1.2 found in NT 3.51 and NT 4
  • v3.0 found in Windows 2000
  • v3.1 found in Windows XP, Windows Server 2003, and Windows Vista

These final three versions are sometimes referred to as v5.0, v5.1, and v6.0, after the version of Windows with which they ship. Each newer version added extra features, for example Windows 2000 introduced quotas. A disk quota is a limit set by a system administrator that restricts certain aspects of file system usage on modern operating systems. ...

Contents

Internals

In NTFS, everything that has anything to do with a file (file name, creation date, access permissions and even contents) is stored as metadata. This abstract approach allowed easy addition of filesystem features during the course of Windows NT's development — an interesting example is the addition of fields for indexing used by the Active Directory software. A computer file is a collection of information that is stored in a computer system and can be identified by its full path name. ... Metadata (Greek meta after and Latin data information) are data that describe other data. ... Typically Active Directory is managed using the graphical Microsoft Management Console. ...


NTFS allows any sequence of short values for file encoding. This means UTF-16 codepoints are supported, but the filesystem does not check whether the sequence is valid UTF-16 (it allows any sequence of short values, not restricted to those in the Unicode standard). In computing, UTF-16 is a 16-bit Unicode Transformation Format, a character encoding form that provides a way to represent a series of abstract characters from Unicode and ISO/IEC 10646 as a series of 16-bit words suitable for storage or transmission via data networks. ...


Internally, NTFS uses B+ trees to index file system data. Although complex to implement, this allows faster access times in some cases. A file system journal is used in order to guarantee the integrity of the file system itself (but not of each individual file). Systems using NTFS are known to have improved reliability compared to FAT file systems.[3] A simple B+ tree example linking the keys 1-7 to data values d1-d7. ...


The Master File Table (MFT) essentially contains metadata about every file and directory on an NTFS file system. It includes parameters such as location, size, and permissions. It is used to aid in minimizing disk fragmentation. Metadata (Greek meta after and Latin data information) are data that describe other data. ... In computing, file system fragmentation, sometimes called file system aging, is the inability of a file system to lay out related data sequentially (contiguously), an inherent phenomenon in storage-backed file systems that allow in-place modification of their contents. ...


Interoperability

Details on the implementation's internals are closed, so third-party vendors have a difficult time providing tools to handle NTFS.


Linux

A number of different software implementations have been developed to allow NTFS volumes to be read, and in some cases modified, under Linux:

  • NTFS partitions can be read by the Linux kernel since version 2.2.0.
  • Linux 2.6 contains a new driver written by Anton Altaparmakov (Cambridge University) and Richard Russon. It offers only file overwrite and file resize support, in some cases.
  • NTFSMount: More write support is available using ntfsmount,[4] a userspace driver written by Yura Pakhuchiy in which files and directories can be created, overwritten, renamed, deleted, truncated, and expanded with limited success.
  • NTFS-3G: In July of 2006, a GPL licensed, open source read-write driver, called NTFS-3G,[5] was introduced by Szabolcs Szakacsits. It has been based on ntfsmount and offers unlimited file creation, deletion, and many other functionality and performance improvements and fixes. The driver is in stable status since February of 2007 and included in most Linux distributions.
  • NTFS for Linux: Full write support is available using Paragon's NTFS for Linux driver, although criticised for leaving many errors on the volume when mounted read-write.[citation needed]
  • Captive NTFS: The Windows driver ntfs.sys can be used with Captive NTFS.

Due to the complexity of the internal NTFS structures, both the built-in 2.6.14 kernel driver and the FUSE drivers will deny changes to the volume when they are considered to be unsafe; thus avoiding corruption. The Linux kernel is a Unix-like operating system kernel. ... The University of Cambridge (usually abbreviated as Cantab. ... NTFS-3G is an open source, freely available NTFS driver for Linux with read and write support. ... Captive NTFS is a modern open source programming effort and project within the Linux programming community, started by Jan Kratochvil, to create a software wrapper around the original Microsoft Windows NTFS file system driver DLLs, in order to more fully implement safer compatibility of file read/write operations from... Filesystem in Userspace (FUSE) is a Free (GPL and LGPLed) Unix kernel module that allows non-privileged users to create their own file systems without the need to write any kernel code. ...


Windows

There are technical considerations for mounting newer NTFS volumes in older versions of Windows. This affects dual-booting, and external portable hard drives.


For example, "Previous Versions" (a.k.a. shadow copies) will be lost because the older OS doesn't understand how to keep the new feature's data updated.[6]


Others

FreeBSD, eComStation and Mac OS X versions 10.3 and later offer read-only NTFS support (there is a beta NTFS driver that allows write/delete for eComStation, but is generally considered unsafe). A free third-party tool for BeOS, which was based on NTFS-3G, allows full NTFS read and write. The read/write NTFS-3G driver has been also ported to FreeBSD, Mac OS X, NetBSD, Haiku and FreeDOS. FreeBSD is a Unix-like free operating system descended from AT&T UNIX via the Berkeley Software Distribution (BSD) branch through the 386BSD and 4. ... The correct title of this article is eComStation. ... Mac OS X (official IPA pronunciation: ) is a line of proprietary, graphical operating systems developed, marketed, and sold by Apple Inc. ... BeOS is an operating system for personal computers which began development by Be Inc. ...


Compatibility with FAT

Microsoft currently provides a tool (convert.exe) to convert HPFS (only on Windows NT 3), FAT16 and, on Windows 2000 and higher, FAT32 to NTFS, but not the other way around [1]. Various third-party tools are all capable of safely resizing NTFS partitions. Microsoft added the ability to expand the size of NTFS partitions in Windows Server 2003 using the Diskpart command line tool, and shrinking a partition was introduced with Windows Vista. HPFS or High Performance File System, is a file system created specifically for the OS/2 operating system to improve upon the limitations of the FAT file system. ... File Allocation Table (FAT) is a partially patented file system developed by Microsoft for MS-DOS and was the primary file system for consumer versions of Microsoft Windows up to and including Windows Me. ... Windows Server 2003 is a server operating system produced by Microsoft. ... Windows Vista is the latest release of Microsoft Windows, a line of graphical operating systems used on personal computers, including home and business desktops, notebook computers, Tablet PCs, and media centers. ...


For historical reasons, the versions of Windows that do not support NTFS all keep time internally as local zone time, and therefore so do all file systems other than NTFS that are supported by current versions of Windows. However, Windows NT and its descendants keep internal timestamps as UTC and make the appropriate conversions for display purposes. Therefore, NTFS timestamps are in UTC. This means that when files are copied or moved between NTFS and non-NTFS partitions, the OS needs to convert timestamps on the fly. But if some files are moved when daylight saving time (DST) is in effect, and other files are moved when standard time is in effect, there can be some ambiguities in the conversions. As a result, especially shortly after one of the days on which local zone time changes, users may observe that some files have timestamps that are incorrect by one hour. Due to the differences in implementation of DST between the northern and southern hemispheres, this can result in a potential timestamp error of up to 4 hours in any given 12 months.[7] ... Daylight saving time around the world  DST used  DST no longer used  DST never used Daylight saving time (DST), also summer time in British English, is the convention of advancing clocks so that afternoons have more daylight and mornings have less. ... Universal Time (UT) is a timescale based on the rotation of the Earth. ...


Features

NTFS v3.0, the third version of NTFS to be introduced, includes several new features over its predecessors: disk usage quotas, sparse file support, reparse points, distributed link tracking and file-level encryption, also known as the Encrypting File System (EFS).

Alternate data streams (ADS) 
Alternate data streams allows files to be associated with more than one data stream. For example, a file such as text.txt can have an ADS with the name of text.txt:secret.txt (of form filename:ads) that can only be accessed by knowing the ADS name or by specialized directory browsing programs. Alternate streams are not detectable in the original file's size but are lost when the original file (i.e. text.txt) is deleted with a RemoveFile or RemoveFileTransacted call (or a call that uses those calls), or when the file is copied or moved to a partition that doesn't support ADS (e.g. a FAT partition, a floppy disk, or a network share). While ADS is a useful feature, it can also easily eat up hard disk space if unknown either through being forgotten or not being detected.
Quotas 
Disk quotas were introduced in NTFS v3. They allow the administrator of a computer that runs a version of Windows that supports NTFS to set a threshold of disk space that users may utilise. It also allows administrators to keep track of how much disk space each user is using. An administrator may specify a certain level of disk space that a user may use before they receive a warning, and then deny access to the user once they hit their upper limit of space. Disk quotas do not take into account NTFS's transparent file-compression, should this be enabled. Applications that query the amount of free space will also see the amount of free space left to the user who has a quota applied to them.
Sparse files 
Sparse files are files which contain sparse data sets, data mostly filled with zeroes. Many scientific applications can generate very large sparse data sets. Because of this, Microsoft has implemented support for sparse files by only allocating disk space for regions that do not contain blocks of zero data. An application that reads a sparse file reads it in the normal manner with the file system calculating what data should be returned based upon the file offset. As with compressed files, the actual size of sparse files are not taken into account when determining quota limits.[8]
Reparse points 
This feature was introduced in NTFS v3. These are used by associating a reparse tag in the user space attribute of a file or directory. When the object manager (see Windows NT line executive) parses a file system name lookup and encounters a reparse attribute, it knows to reparse the name lookup, passing the user controlled reparse data to every file system filter driver that is loaded into Windows 2000. Each filter driver examines the reparse data to see if it is associated with that reparse point, and if that filter driver determines a match then it intercepts the file system call and executes its special functionality. Reparse points are used to implement Volume Mount Points, Directory Junctions, Hierarchical Storage Management, Native Structured Storage and Single Instance Storage:
Volume mount points 
Similar to Unix mount points, where the root of another file system is attached to a directory. In NTFS, this allows additional file systems to be mounted without requiring a separate drive letter (like C: or D:) for each.
Directory Junctions 
Similar to Volume Mount Points, however directory junctions reference other directories in the file system instead of other volumes. For instance, the directory C:exampledir with a directory junction attribute that contains a link to D:linkeddir will automatically refer to the directory D:linkeddir when it is accessed by a user-mode application. They are the equivalent of a Unix symbolic link, though in Unix a symbolic link can be applied on files as well as on directories.[9]
Hard links 
Hard links are similar to directory junctions, but used for files instead of directories. Hard links can only be applied to files on the same volume since an additional filename record is added to the file's MFT record. Short (8.3) filenames are also implemented as additional filename records that don't have separate directory entries.
Hierarchical Storage Management (HSM) 
Hierarchical Storage Management is a means of transferring files that are not used for some period of time to less expensive storage media. When the file is next accessed the reparse point on that file determines that it is needed and retrieves it from storage.
Native Structured Storage (NSS) 
NSS was an ActiveX document storage technology that has since been discontinued by Microsoft. It allowed ActiveX documents to be stored in the same multi-stream format that ActiveX uses internally. An NSS file system filter was loaded and used to process the multiple streams transparently to the application, and when the file was transferred to a non-NTFS formatted disk volume it would also transfer the multiple streams into a single stream.[10]
Volume Shadow Copy 
The Volume Shadow Copy (VSC) service keeps historical versions of files and folders on NTFS volumes by copying old, newly-overwritten data to shadow copy (copy-on-write). The old file data is overlaid on the new when the user requests a revert to an earlier version. This also allows data backup programs to archive files currently in use by the file system. On heavily loaded systems, Microsoft recommends setting up a shadow copy volume on separate disk to reduce the I/O load on the main volume.
File compression 
NTFS can compress files using a variant of the LZ77 algorithm (also used in the popular ZIP file format).[11] Although read-write access to compressed files is transparent, Microsoft recommends avoiding compression on server systems and/or network shares holding roaming profiles because it puts a considerable load on the processor.[12]
Single-user systems with limited hard disk space will probably use NTFS compression successfully. The slowest link in the 2.5 inch drive of a notebook computer is not the CPU, but the speed of the drive, so NTFS compression allows the limited storage space to be better used.
Single Instance Storage (SIS) 
When there are several directories that have different, but similar, files, some of these files may have identical content. Single instance storage allows identical files to be merged to one file and create references to that merged file. SIS consists of a file system filter that manages copies, modification and merges to files; and a user space service (or groveler) that searches for files that are identical and need merging. SIS was mainly designed for remote installation servers as these may have multiple installation images that contain many identical files; SIS allows these to be consolidated but, unlike for example hard links, each file remains distinct; changes to one copy of a file will leave others unaltered. This is similar to copy-on-write, which is a technique by which memory copying is not really done until one copy is modified.[13]
Encrypting File System (EFS) 
EFS provides strong and user-transparent encryption of any file or folder on an NTFS volume. EFS works in conjunction with the EFS service, Microsoft's CryptoAPI and the EFS File System Run-Time Library (FSRTL).
EFS works by encrypting a file with a bulk symmetric key (also known as the File Encryption Key, or FEK), which is used because it takes a relatively smaller amount of time to encrypt and decrypt large amounts of data than if an asymmetric key cipher is used. The symmetric key that is used to encrypt the file is then encrypted with a public key that is associated with the user who encrypted the file, and this encrypted data is stored in an alternate data stream of the encrypted file. To decrypt the file, the file system uses the private key of the user to decrypt the symmetric key that is stored in the file header. It then uses the symmetric key to decrypt the file. Because this is done at the file system level, it is transparent to the user.[14] Also, in case of a user losing access to their key, support for recovery agents that can unencrypt files has been built in to the EFS system.
Symbolic links 
Symbolic links were introduced in Windows Vista.[15]
Transactional NTFS 
As of Windows Vista, applications can use Transactional NTFS to group changes to files together into a transaction. The transaction will guarantee that all changes happen, or none of them do, and it will guarantee that applications outside the transaction will not see the changes until the precise instant they're committed.[16]

In computing, a fork is additional data associated with a file system object. ... A disk quota is a limit set by a system administrator that restricts certain aspects of file system usage on modern operating systems. ... In computer science, a sparse file is a type of computer file that attempts to use file system space more efficiently. ... In the mathematical subfield of numerical analysis a sparse matrix is a matrix populated primarily with zeros. ... 0 (zero) is both a number and a numerical digit used to represent that number in numerals. ... The Windows NT operating system familys architecture consists of two layers (user mode and kernel mode), with many different modules within both of these layers. ... Filiation of Unix and Unix-like systems Unix (officially trademarked as UNIX®) is a computer operating system originally developed in the 1960s and 1970s by a group of AT&T employees at Bell Labs including Ken Thompson, Dennis Ritchie and Douglas McIlroy. ... A mount point is a term used to describe where the computer puts the files in a file system on Unix-like systems. ... An NTFS junction point (JP) is a feature of the NTFS file system version 3. ... In computing, a symbolic link (often shortened to symlink and also known as a soft link) consists of a special type of file that serves as a reference to another file. ... In computing, a hard link is a reference, or pointer, to physical data on a storage volume. ... Hierarchical Storage Management (HSM) is a data storage technique that automatically moves data between high-cost and low-cost storage media. ... ActiveX is a series of high-level, Internet/Intranet technologies Microsoft introduced in late 1990s. ... The Volume Shadow Copy Service in modern versions of the Microsoft Windows operating system provides periodic snapshots of a systems volumes. ... Copy-on-write (sometimes referred to as COW) is an optimization strategy used in computer programming. ... In computer science and information theory, data compression or source coding is the process of encoding information using fewer bits (or other information-bearing units) than an unencoded representation would use through use of specific encoding schemes. ... LZ77 and LZ78 are the names for the two lossless data compression algorithms published in papers by Abraham Lempel and Jacob Ziv in 1977 and 1978. ... The ZIP file format is the most widely-used compressed file format in the IBM PC world. ... In human-computer interaction, computer transparency is an aspect of user friendliness which prevents the user from worrying about technical details (like installation, updating, downloading or device drivers). ... When several files in a computer filesystem contain exactly the same data, single instance storage can replace the references to these identical files by references to a single stored copy of the file. ... Copy-on-write (sometimes referred to as COW) is an optimization strategy used in computer programming. ... The EFS or Encrypting File System is a file system available in Microsofts Windows 2000, Windows XP,Windows Server 2003, and now Windows Media Center 2005 operating systems. ... The Cryptographic Application Programming Interface (also known variously as CryptoAPI, Microsoft Cryptography API, or simply CAPI) is an application programming interface included with Microsoft Windows operating systems that provides services to enable developers to secure Windows-based applications using cryptography. ... Symmetric-key algorithms are a class of algorithms for cryptography that use trivially related cryptographic keys for both decryption and encryption. ... In cryptography, an asymmetric key algorithm uses a pair of cryptographic keys to encrypt and decrypt. ... Public key cryptography is a form of cryptography which generally allows users to communicate securely without having prior access to a shared secret key, by using a pair of cryptographic keys, designated as public key and private key, which are related mathematically. ... In computing, a symbolic link (often shortened to symlink and also known as a soft link) consists of a special type of file that serves as a reference to another file. ... Windows Vista is the latest release of Microsoft Windows, a line of graphical operating systems used on personal computers, including home and business desktops, notebook computers, Tablet PCs, and media centers. ...

Limitations

The following are a few limitations of the NTFS file system.

Reserved File Names 
Though the file system supports paths up to ca. 32,000 Unicode characters with each path component (directory or filename) up to 255 characters long, certain names are unusable, since NTFS stores its metadata in regular (albeit hidden and for the most part inaccessible) files; accordingly, user files cannot use these names. These files are all in the root directory of a volume (and are reserved only for that directory). The names are: $MFT, $MFTMirr, $LogFile, $Volume, $AttrDef, . (dot), $Bitmap, $Boot, $BadClus, $Secure, $Upcase, and $Extend;[17] . (dot) and $Extend are both directories, the others are files.
Maximum Volume Size 
In theory, the maximum NTFS volume size is 264-1 clusters. However, the maximum NTFS volume size as implemented in Windows XP Professional is 232-1 clusters. For example, using 64 KiB clusters, the maximum NTFS volume size is 256 TiB minus 64 KiB. Using the default cluster size of 4 KiB, the maximum NTFS volume size is 16 TiB minus 4 KiB. Because partition tables on master boot record (MBR) disks only support partition sizes up to 2 TiB, you must use dynamic volumes to create NTFS volumes over 2 TiB.
Maximum File Size 
Theoretical: 16 EiB minus 1 KiB (264 − 210 bytes). Implementation: 16 TiB minus 64 KiB (244 − 216 bytes)
Alternate Data Streams 
Care must be exercised when copying or moving files from NTFS to other filesystem types. Windows system calls and programs can have varying behavior with regard to alternate data streams and might silently strip those which could not be stored on the destination filesystem. A safe way of copying or moving files is to use the BackupRead and BackupWrite system calls, which allow to enumerate streams, to verify whether each stream could be written to the destination volume and to knowingly skip offending streams.
Maximun date 
NTFS or NT File System was built to only recognize dates up to May 28, 60,056. After this date everything would reverse back to the date of January 1, 1601. An example of this would be the Y2K scare where there were thought to be many computers that could not handle the date jump to 2000.

According to the International Electrotechnical Commission a kibibyte (a contraction of kilo binary byte) is a unit of information or computer storage. ... EIB may stand for: Even in Blackouts European Installation Bus European Investment Bank Excellence In Broadcasting Expert Infantry Badge Extreme Ironing Bureau This page concerning a three-letter acronym or abbreviation is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... A tebibyte is a unit of information or computer storage, commonly abbreviated TiB. 1 tebibyte = 240 bytes = 1 099 511 627 776 bytes The tebibyte is closely related to the terabyte, which can either be a synonym for tebibyte, or refer to 1012 bytes = 1 000 000 000 000 bytes... May 28 is the 148th day of the year in the Gregorian calendar (149th in leap years). ... NTFS or New Technology File System[2] is the standard file system of Windows NT and its descendants Windows 2000, Windows XP, Windows Server 2003, and Windows Vista. ... January 1 is the first day of the calendar year in both the Julian and Gregorian calendars. ... Events February 8 - Robert Devereux, 2nd Earl of Essex, rebels against Elizabeth I of England - revolt is quickly crushed February 25 - Robert Devereux beheaded Jesuit Matteo Ricci arrives in China Bad harvest in Russia due to rainy summer Dutch troops drive Portuguese from Málaga Battle of Kinsale, Ireland Births...

Developers

NTFS was developed by:

Tom Miller is a software developer who was employed by Microsoft. ... Gary D. Kimura is a software developer who worked for Microsoft. ...

Notes

  1. ^ UTF-16 codepoints accepted, but not validated
  2. ^ Helen Custer (1994). Inside the Windows NT File System. Microsoft Press. ISBN 1-55615-660-X. 
  3. ^ "Microsoft TechNet Resource Kit"
  4. ^ "ntfsmount wiki page on linux-ntfs.org"
  5. ^ "ntfs-3g announcement in linux-ntfs-dev list"
  6. ^ cfsbloggers (July 14, 2006). How restore points and other recovery features in Windows Vista are affected when you dual-boot with Windows XP. The Filing Cabinet. Retrieved on 2007 March 21.
  7. ^ "Beating the Daylight Savings Time bug and getting correct file modification times" The Code Project
  8. ^ "Sparse Files", MSDN Platform SDK: File Systems. Retrieved May 22, 2005.
  9. ^ Mark Russinovich, "Inside Win2K NTFS, Part 1"
  10. ^ John Saville, "What is Native Structured Storage?"
  11. ^ "File Compression and Decompression". MSDN Platform SDK: File Systems. Retrieved Aug 18, 2005.
  12. ^ "Best practices for NTFS compression in Windows." Microsoft Knowledge Base. Retrieved Aug 18, 2005.
  13. ^ Single Instance Storage in Windows 2000 (PDF). Microsoft Research and Balder Technology Group.
  14. ^ "How EFS Works" Microsoft Windows 2000 Resource Kit
  15. ^ Symbolic Links. MSDN. Retrieved on 2007 January 5.
  16. ^ Transactional NTFS. MSDN. Retrieved on 2007 February 2.
  17. ^ "How NTFS Works" Windows Server 2003 Technical Reference

2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the Anno Domini (common) era. ... March 21 is the 80th day of the year in the Gregorian calendar (81st in leap years). ... Microsoft Research is a division of Microsoft that is devoted to researching various computer science topics and issues. ... The Microsoft Developer Network (MSDN) is an information service from Microsoft for software developers. ... 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the Anno Domini (common) era. ... January 5 is the 5th day of the year in the Gregorian calendar. ... The Microsoft Developer Network (MSDN) is an information service from Microsoft for software developers. ... 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the Anno Domini (common) era. ... February 2 is the 33rd day of the year in the Gregorian Calendar. ...

References

  • Bolosky, William J.; Corbin, Scott; Goebel, David; & Douceur, John R. (date). "Single Instance Storage in Windows 2000" (PDF). Microsoft Research & Balder Technology Group, Inc..
  • Custer, Helen (1994). Inside the Windows NT File System. Microsoft Press. ISBN 1-55615-660-X. 
  • Nagar, Rajeev (1997). Windows NT File System Internals: A Developer's Guide (1st ed). O'Reilly. ISBN 1-56592-249-2. 

See also

Files-11, also known as on-disk structure, is the filesystem used by Hewlett-Packards OpenVMS operating system, and also (in a simpler form) by the older RSX-11. ... The following tables compare general and technical information for a number of file systems. ... Captive NTFS is a modern open source programming effort and project within the Linux programming community, started by Jan Kratochvil, to create a software wrapper around the original Microsoft Windows NTFS file system driver DLLs, in order to more fully implement safer compatibility of file read/write operations from... NTFS-3G is an open source, freely available NTFS driver for Linux with read and write support. ...

External links

  • Linux-NTFS – an open source project to add NTFS support to the Linux kernel (write support is limited, but can be used for simple tasks), and write POSIX-compatible utilities for accessing and manipulating NTFS (ntfsprogs; includes ntfsls, ntfsresize, ntfsclone, etc)
  • NTFS-3G – NTFS-3G read/write driver for Linux
  • Captive NTFS – a shim which used the Windows NTFS driver to access NTFS filesystems under Linux
  • NTFS.com – documentation and resources for NTFS
  • Microsoft NTFS Technical Reference


 
 

COMMENTARY     


Share your thoughts, questions and commentary here
Your name
Your comments

Want to know more?
Search encyclopedia, statistics and forums:

 


Lesson Plans | Student Area | Student FAQ | Reviews | Press Releases |  Feeds | Contact
The Wikipedia article included on this page is licensed under the GFDL.
Images may be subject to relevant owners' copyright.
All other elements are (c) copyright NationMaster.com 2003-5. All Rights Reserved.
Usage implies agreement with terms, 1022, m