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File Management in

Windows NT

PRESENTED TO : DR. RANVIJAY SINGH Asim K. Prasad Kishan Patel Manish K. Sinha Md. Sk Abid Hasan

Attributes In File Management

with aspect of Windows NT

 (^) Files and File Systems  (^) File Organization and Access  (^) File Directories  (^) File Sharing  (^) Secondary Storage Management  (^) File System Security

Files & Databases To understand what file is, first of all, we need to know about  (^) Field A field is the basic element of data. An individual field contains a single value, such as an employee’s last name, a date, or the value of a sensor reading.  (^) Record A record is a collection of related fields that can be treated as a unit by some application program. A file is a collection of similar records. The file is treated as a single entity by users and applications and may be referenced by name. Files have file names and may be created and deleted. A database is a collection of related data. The essential aspects of a database are that the relationships that exist among elements of data are explicit and that the database is designed for use by a number of different applications.

Secondary Storage Management

FAT File System

(File Allocation Table)

Partitions formatted with FAT are broken into clusters. The FAT file system is also prone to fragmentation , which is the result of data being written to noncontiguous clusters, which can slow down the read/write process. FAT writes files to the first available cluster it can find, and then skips ahead past used clusters to complete writing a file. These clusters are broken down into sectors. FAT also keeps track of a few attributes for each file, such as the name of the file, the address of the starting sector, whether the file was deemed a system file, a read-only attribute, an archive bit (denoting if the file had been backed up or changed since the last time it was backup up), and a date for the file's creation or the last time the file was modified. Because the overhead of using the FAT file system grows as partition size increases, it is advisable to not use FAT on partitions that are greater than 200 megabytes.

Chain Allocation and Post Consolidation

Indexed Allocation

Features of NTFS  (^) Recoverability  (^) Security  (^) Large Disk And Large files  (^) Multiple data stream  (^) Compression and Encryption

NTFS Volume and File Structure

NTFS makes the use of the following disk storage concepts.  (^) Sector – smallest physical storage unit of disk  (^) Cluster – collection of sector  (^) Volume – logical partition of disk consisting of one or more clusters.

Master File Table

The MFT is organized as a table of 1024-byte rows,

called records. Each row describes a file on this volume,

including the MFT itself, which is treated as a file. If the

contents of a file are small enough, then the entire file is

located in a row of the MFT. Otherwise, the row for that

file contains partial information and the remainder of the

file spills over into other available clusters on the

volume, with pointers to those clusters in the MFT row of

that file.

File Directory Structure A directory structure is the way an operating system's file system and its files are displayed to the user. Files are typically displayed in hierarchical file structure. The root directory is " _drive:_ ", for example, the root directory is usually " _C:_ ". The directory separator is usually a " __ ", but the operating system also internally recognizes a " / ". There are independent root directories on each drive.

File Sharing in Windows NT  (^) Windows NT Server enables you to designate resources you want to share with others. For example, when a directory is shared, authorized users can make connections to the directory.  (^) Once a resource is shared, you can restrict its availability over the network to certain users. These restrictions, called share permissions , can vary from user to user. With Windows NT Server, you create the appropriate level of network resource security with a combination of resource sharing and resource permissions.  (^) Following are sharing permissions that can be given to users in Windows NT:  (^) Full Control (default)  (^) Change  (^) Read  (^) No Access

File Security In Windows NT The Windows NT operating system provides a number of primary security functions to control access , they are:  (^) Security Policy Definitions  (^) File And Object Access  (^) Registry Access