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Nt File System

An improvement to the FAT file systems is the New Technology File System (NTFS) used in Windows 2000/NT/XP and other more recent versions of Windows including Windows Vista. In NTFS, the cluster size is variable depending on the size of the logical drives. The cluster size is automatically determined by the NTFS Format utility, thereby, providing a level of flexibility. This flexibility is not available in FAT16 or FAT32. These features enable more efficient allocation of disk space.

One important feature of NTFS is recoverability. NTFS maintain the consistency of data using journaling, keeping a log of each I/O operation that modifies a system file within a logical drive. If the system fails, the file directory structure can be recovered based on the history of the I/O operations performed on the file system. Another feature of the NTFS on Windows is the Encrypted Files System (EFS). EFS enables data to be encrypted as it is saved to disk. NTFS also supports data access control and ownership privileges to restrict unauthorized access to data in a multi-user environment.

The chart below compares NTFS and FAT files systems.

 

NTFS versus FAT

 

NTFS

FAT32

FAT16

Operating System

  • Windows XP

  • Windows 2000

  • Windows NT and all versions since these including Vista

  • Windows XP

  • Windows 2000

  • Windows 98

  • Windows ME

  • Windows 95 OEM Service Release 2 (OSR2)

  • All versions of  Microsoft Windows

  • DOS

Max Volume Size*

2 TB

32 GB

2 GB

Files per Volume*

~ 4 billion

~ 4 million

~ 64,000

Max File Size*

2 TB

4 GB

2 GB

* Values pertain to size limitations during implementation.

Table 1 NTFS versus FAT

Source: Windows 2000: File Systems and Windows XP Professional Resource Kit : Working with File Systems

Assessments:

  • Exercise 3

Unit 4. Application Software

This unit focuses on application software. One specific class of application software, databases, will be discussed in more detail. In addition, you will learn about software licenses and the process of developing software, which is called software engineering.

Readings:

  • 4.1 Software Basics

  • 4.2 Using Software Systems

  • 4.3 Batch Script Files

  • 4.4 Databases

  • 4.5 Software Engineering

          

Assessments:

  • Exercise 4

4.1 Software Basics

Because software is nothing more than information, users may not realize that it is property, with important legal protections. When you purchase a piece of software, you own the physical medium on which it is distributed, typically a diskette or CD. However, the software itself is owned by the author or copyright holder, and what you may legally do with it is determined by the license that was granted at the time of purchase. This section explores some of the types of software licenses that exist and the implications of the licensing agreement for a user.

Reading Sequence:

  • Parsons/Oja, Chapter 3-Section A. Learning Goal: Knowledge of the various types of software that exist, how they are created, and in general, how they work.

  • Parsons/Oja, Chapter 3-Section D. Learning Goal: Knowledge of software licenses and installation procedures. -When installing software, do you read the licensing agreement before clicking the I Accept button? -Do you know the restrictions that apply when making copies of software programs?  -Do you know what legal options you have when software doesn't work as advertised?  -Do you know at what point you become bound by a shrink-wrap license?  If your answer to any of these questions is "No", this is an important reading for you. 

  • Parsons/Oja, Issue: "How serious is Software Piracy" in Chapter 3. Learning Goal: Knowledge of software copyright law and the problem of software piracy. Do computer programs have anything in common with books and magazine articles? Unlike books and articles, computer programs are sets of instructions in a particular sequence that perform actions; however, like books and articles, computer programs are products of a creative process—the results of which are subject to copyright protection.

           

Assessments:

  • Multiple-Choice Quiz 12