Windows XP provides several advanced features to efficiently secure and manage files and folders locally as well as across a network. Files and folders that exist on Windows XP-based computers contain a certain number of attributes that control and govern their accessibility and display features. These attributes entirely depend on the file system that the operating system uses. A file system is a way of storing and organizing the files and folders on the hard disk of a computer. Windows XP supports both the FAT as well as the advanced NTFS file systems. NTFS-formatted volumes support several features that facilitate users in managing files and folders. These features are described as follows:

Compression

Compression is an NTFS attribute of files and folders. It increases the amount of available hard disk space by reducing the size of the files or folders. Compressing files and folders on a computer allows users to store more data on the computer's hard disk. NTFS supports compression on volumes, folders, as well as on the files that are compressed on an NTFS volume. A user can read a compressed file located on an NTFS volume without decompressing it. The file is decompressed automatically as soon as the file read process starts. On a volume that is running low on the available disk space, the compression proves to be a very effective means of increasing the empty space on the hard disk, thereby managing the disk space. A user can control the compression attributes on the files or folders individually.

In order to enable compression on a file, folder, or a complete NTFS volume, a user has to follow the steps given below:

Right-click the volume, file, or the folder, and select Properties.

On the General tab page of the Properties dialog box for the file, folder, or volume, click the Advanced button.
In the Advanced Attributes dialog box, select the Compress Contents To Save Disk Space check box in the Compress or Encrypt attributes section, and click the OK button.
Moving and copying compressed files and folders: When a user moves or copies compressed files and folders in Windows, these files and folders are affected in the following manner:

When the files and folders are moved within the NTFS volume, the compression attribute remains the same in the new location irrespective of the status of the destination folder (i.e., whether it is compressed or uncompressed).

When the files and folders are copied within the same volume from one location to another, the original compression attribute is lost and the files inherit the attributes of the new parent folder (destination).

When the files and folders are copied or moved to a different volume, the compression attribute is lost and the files or folders inherit the attributes of the destination folder.

Copying or moving compressed files and folders from an NTFS volume to a FAT or FAT32 volume does not sustain the compression because FAT or FAT32 does not support compression of files or folders.
Windows XP supports a new feature called compressed (zipped) folder. This feature can be used on volumes with either the FAT or NTFS file system, or both. The compressed (zipped) folder can be easily shared with other users even if they are not running Windows XP Professional or using a drive formatted with the NTFS file system.

Supporting File Encryption

File encryption is a file attribute that allows a user to protect files and folders. It is a way of making data illegible to protect it from unauthorized users, especially during network transmission. Windows XP Professional allows a user to protect the files and folders by using the Encrypting File System (EFS). EFS encodes a file in a manner so that a user cannot read the file's data even if he gets access to the file. Only an authorized user can read the file. When an unauthorized user attempts to access an EFS-encrypted resource, the user receives the Access Denied message. EFS implementation consists of two restrictions. First, an EFS-encryption can be used only on volumes formatted as NTFS, and secondly, a user cannot use EFS to encrypt a file that has been compressed by using NTFS compression. By default, Windows XP displays the names of encrypted files with a green color. A user can also change the color as per his requirement.

Managing Disk Quotas

Disk quota is a very efficient disk management feature of Windows XP Professional. The administrators on NTFS-formatted volumes can use this feature. It allows administrators to limit or fix the amount of disk space for multiple users on an NTFS volume. Disk quotas provide system administrators with a powerful tool for managing storage growth. Administrators can set both soft and hard limits, i.e., when a user exceeds a warning level (soft limit), an event is logged; when a user exceeds the hard limit, they receive an Out of Disk error. Disk quotas apply to the entire volume. It cannot be configured on a folder-by-folder basis. When a user reaches or exceeds the assigned quota limit, he will have to delete files to create empty space, transfer the ownership of some of his files to other users, or ask the administrator to provide more disk space. Compression does not work when the limit is exceeded. Merely by compressing some of the folders, a user cannot increase the available disk space in his assigned quota.

Managing Security

Windows XP provides an excellent way of securing the shared files and folders across a network by properly assigning the standard NTFS permissions. There are six basic NTFS folder permissions and five basic NTFS file permissions. In addition to these standard permissions, an NTFS-formatted volume also provides advanced files and folders permissions that an administrator can assign in a more specific manner. The system or network administrators on both files as well as folders can apply all of these permissions. The entire assigned standard as well as the advanced permissions can be viewed on the Security tab page of the File's or Folder's Properties dialog box.

Another way of managing security is to control the permission inheritance. When an administrator assigns some NTFS permissions on a folder, all the files and subfolders within the parent folder automatically inherit the parent folder's permissions. This is called permission inheritance. An administrator can stop such inheritance either at the parent level or child level by configuring the Security tab page of the Parent folder's dialog box. Therefore, Windows XP with the NTFS-formatted volume provides a very effective and efficient way of managing the files and folders both locally as well as in a networked environment.