Chapter Summary

• Windows XP provides access to local, shared, and offline files.

• A file name extension is a set of characters at the end of a file name that describes the type of information that is stored in the file. A file name extension can also indicate which application is associated with the file.

• File compression reduces the amount of disk space required for the storage of files and increases the amount of information that you can place on a single volume. This is useful on a volume that is running low on available disk space. Windows XP Professional supports file compression on NTFS volumes only. (Windows XP Home Edition does not support file compression.)

• In Windows XP Professional, you can protect files and folders by using the Encrypting File System (EFS). (EFS is not available in Windows XP Home Edition.) EFS encodes your files so that even if a person can obtain the file, he cannot read it.

• Disk quotas allow you to track and control disk space usage. You can enable disk quotas strictly for the purpose of monitoring how much disk space each user is consuming, or you can take the additional step to configure and enforce quota limits.

• Every file and folder on an NTFS volume has a discretionary access control list (DACL) associated with it. The DACL contains the user accounts and groups that have been assigned permissions to a resource and the permissions that have been granted. Each entry in the DACL is called an access control entry (ACE). A user account or a group that the user account is a member of, must be listed as an ACE in the DACL for the user account to gain access to a resource.

• Basic file and folder permissions include: List Folder Contents, Read, Write, Read & Execute, Modify, and Full Control.

• When assigning permissions, you should grant the user the lowest level of permission required to access the resources in the appropriate fashion.

• For each permission, you can choose one of two states: allow or deny. In most cases, you will allow specific permissions, which provide the user with the ability to perform the specified function. When you deny a permission, that denial overrides any allowances of the same permission that may come from other sources.

• When you calculate effective NTFS permissions, you should combine all allowed permissions. A denied permission always overrides an allowed permission.

• To create shared folders on a computer running Windows XP Professional, you must be a member of the Administrators or Power Users groups. Also, users granted the Create Permanent Shared Objects user right can also share folders.

• Using a $ at the end of a share name creates a hidden share, which prevents users who are browsing the network from seeing the share. Users have to know the name and location of the share to connect to it.

• You can share the same folder multiple times with different share names and different permissions assignments. This sharing is useful if diverse groups of users would recognize the same data more intuitively under different share names or if different users require different levels of share permissions for the same folder.

• You can protect shared folders by using shared folder permissions or by using a combination of shared folder and NTFS permissions. When shared and NTFS permissions are applied, the cumulative permissions of both are determined, and the most restrictive of those permissions create the user’s effective permission.

• Simple File Sharing is a simplified sharing model that allows users to easily share folders and files with other local users on the same computer or with users in a workgroup without having to worry about configuring NTFS permissions and standard shared folders.

• Windows XP Home Edition supports only Simple File Sharing. Windows XP Professional supports Simple File Sharing in a workgroup setting, but not when a computer is a member of a domain.

• By using Simple File Sharing, you can share folders and files with other local users on the same computer by placing the folders and files in the Shared Documents folder. You can share folders with network users by using the Sharing tab of a folder’s Properties dialog box.

• On volumes that are formatted with NTFS, you can also make folders private, which prevents access by other users on the same computer and users on the network.

• When files and folders on network servers are made available offline, users will continue to have access to those resources even when they are not connected to the network.

• All shared folders are available offline by default, although you can control the caching settings available or disable offline access.

• You must enable the Offline Files feature before you can select network shares to make available offline on the client computer. After the feature is enabled, you can select a shared folder on the network and make it available offline.

• Offline files are synchronized at logon and logoff by default, though you can also initiate a manual synchronization.