What is NTFS?

Summary

When a volume is formatted with the NT file system (NTFS), multiple NTFS system files are created in the root directory of the NTFS volume. These system files can be stored at any location on the NTFS volume. Consequently, damage to certain locations on the volume will not as likely render the entire volume inaccessible. Listed below is a description of the ten NTFS system files currently implemented in the retail version of Windows NT.

NTFS Overview

From a user’s point of view, NTFS continues to organize files into directories. However, unlike FAT or HPFS, there are no “special” objects on the disk and there is no dependence on the underlying hardware, such as 512 byte sectors. In addition, there are no special locations on the disk, such as FAT tables or HPFS Super Blocks.

The goals of NTFS are to provide:
  • Reliability, which is especially desirable for high end systems and file servers
  • A platform for added functionality
  • Support POSIX requirements
  • Removal of the limitations of the FAT and HPFS file systems

Advantages of NTFS

NTFS is best for use on volumes of about 400 MB or more. This is because performance does not degrade under NTFS, as it does under FAT, with larger volume sizes. The recoverability designed into NTFS is such that a user should never have to run any sort of disk repair utility on an NTFS partition. For additional advantages of NTFS, see the following:

  • Microsoft Windows NT Server “Concepts and Planning Guide,” Chapter 5, section titled “Choosing a File System”
  • Microsoft Windows NT Workstation 4.0 Resource Kit, Chapter 18, “Choosing a File System”
  • Microsoft Windows NT Server 4.0 Resource Kit “Resource Guide,” Chapter 3, section titled “Which File System to Use on Which Volumes”

Disadvantages of NTFS

It is not recommended to use NTFS on a volume that is smaller than approximately 400 MB, because of the amount of space overhead involved in NTFS. This space overhead is in the form of NTFS system files that typically use at least 4 MB of drive space on a 100 MB partition.

Currently, there is no file encryption built into NTFS. Therefore, someone can boot under MS-DOS, or another operating system, and use a low-level disk editing utility to view data stored on an NTFS volume. It is not possible to format a floppy disk with the NTFS file system; Windows NT formats all floppy disks with the FAT file system because the overhead involved in NTFS will not fit onto a floppy disk.