- Windows File Systems
- Windows ReFS
- Windows NTFS
- Windows DFS
- Windows CIFS
- Virtual Disk Services
- Volume Shadowcopy Services
- Removable Storage System
- Windows Volume Mgmt.
- Windows System state
The various flavours of Windows all need to support older file systems for backward compatibility, as well as new file systems that provide better functionality. The following is a list of most of the supported file systems.
FAT (File Allocation Table) is the file system that has been around since MS-DOS days. Bill Gates supposedly created the original FAT system in 1976, in a hotel room in Albuquerque. It has been superseded by better systems, but is still used for floppy disk support. The original FAT, or FAT16 system supports volumes up to a maximum size of 4 GB. The FAT32 file system will support volumes up to 8 TB (Windows 2000/3 will support 127GB volumes, but can only create 32GB volumes). The FAT32 system also uses a smaller cluster size, so it uses disk space more efficiently than FAT16.
CIFS is an open system which lets groups of users to work together and share documents across the Internet. It is discussed in the CIFS page.
The Compact Disk File System (CDFS) replaced the MS-DOS MSCDEX utility. It is used to read data from CD-ROM devices.
Universal Disk Format (UDF) in turn replaced CDFS. The Optical Storage Technology Association (OSTA) defined the UDF file system to work with CD, DVD
and Magneto Optical storage.
Windows 2000 and 2003 can read UDF version 1.02 and 1.50 files. Microsoft plan to introduce read/write support in the Vista release of Windows
Offline Files was developed by IntelliMirror, and was introduced to Windows 2000. It is intended for mobile users who sometimes log into a network, and sometimes work standalone, and allows them to access locally cached versions of networked files, if they are working stand alone. They can also use locally cached versions of files when they are logged into the network, which can greatly improve network performance.
Windows uses the Synchronisation Manager feature to keep local and remote files in step. Three Synchronisation options are available:
File Replication Service (FRS) was introduced in Windows Server 2000. FRS will synchronise files and folders locally, or between remote servers. It uses the NTFS change journal to identify files that have changed, and must be replicated. It does not provide the same synchronous copy facilities as hardware mirroring, as remote data will not be copied synchronously, that is, the remote data is not guaranteed to be exactly the same as the local data.
FRS can be used in conjunction with DFS to make data on remote sites highly available. FRS is not a replacement for tape backups, as data corruption, accidental deletion and viruses will be replicated to failover disks.
To activate FRS,
FSR was enhanced in Windows 2008 and renamed DFSR (Distributed File System Replication). The main advantage is that DFS will only replicate those parts of files that have changed, rather than replicating an entire changed file.
NTFS was introduced in the Windows NT operating system. Its advantages and disadvantages are discussed in the NTFS page
ReFS was introduced with Windows Server 2012. Its advantages and disadvantages are discussed in the ReFS page
DFS (Distributed File Sharing) was introduced in Windows NT, and then developed further in Windows 2000 and 2003. The idea behind DFS is to hide the location of a file or directory from the user, so that if a file or disk moves around the user is unaware of the details. This is all discussed in the DFS pagebody text