What Is Backup of Data ?

An additional copy of data or information stored on secondary storage media is called the backup of data. The common media for backup are zip disk magnetic lap, floppy disk, CD—ROM and hard disk, etc.

The computer system can be damaged due to many reasons. The data stored on the system may also be lost, deleted, or altered. Sometimes the data is very important and it cannot be created again. For example, a computer in a bank may contain records of all money transactions. The backup of data is used if your system crashes accidentally and the data stored in it is lost.

 

Purpose of Backup

The purposes of taking backup of data are as follows:

1. An important file can be deleted accidentally.
2. The user may overwrite a part or whole of an existing file.
3. A mechanical failure in the computer may result in a loss of data.
4. A virus may damage the data stored on the computer.
5. The computer system may be stolen by anybody.
6. The computer system may be damaged due to fire or power failure.

It is very important to take the backup of data regularly. It should be stored in a safe and protected place. In big organizations, the backup is normally stored on a centralized networked computer. In small organizations, the backup is stored on floppy disks, Zip disks, or CD—ROM.

Types of Backup

There are two ways to take the backup of data:

1. Complete backup

2. Incremental backup

 

1. Complete Backup

Backup of all data on the hard disk is called complete backup. The advantage of this backup is that the entire hard disk is backed-up. The data can be restored from this backup in case of a problem in the system. It takes more time and storage capacity because the entire data of hard disk is copied.

 

2. Incremental Backup

Incremental backup creates a copy of only the data that is newly created or modified since the last backup. This process is performed automatically in some software. In this type of backup, the entire disk is not copied. It takes less time and space than complete backup.

 

Media for Data Backup

Different types of media can be used for backup of data. The selection of media depends upon the nature and quantity of the data to be backed up.

 

1. Floppy Disks

Floppy disks are used for taking backup of small quantities of data. This media is not very much reliable. Floppy disks are damaged in hot, humid, and dusty conditions. It can stare only 1.4 megabytes of data. The size of data can be decreased by using compression software like WinZip.

 

2. Zip Disk

Zip disk is similar to a floppy disk. It is a more reliable medium. The storage capacity of a zip disk is normally 100 MB, 50 MB, or 1000 MB. These are available with Parallel Port Interface or Universal Port (USB) interface.

 

3. Magnetic Tape

Magnetic tape is the most conventional and reliable medium for backup. These are used for backing up several thousand million bytes of data. It is a more expensive medium. The data stored on this media cannot be accessed randomly.

 

4. CD

CD is also an important and commonly used media for backup. This media is reliable and cheap. Data on some types of CDs can be written again and again.

 

 

Strategies for Good Data Backup

The backup of data is an important function in an organization. It must be performed properly. If there is any damage to the system or data, the backup can be restored to run the system properly.

Different strategies for good data backup are as follows:

 

1. Logical Division of Data

The entire information should be divided in a logical way. If the information is stored logically on the computer, the backup will be easy. For example, different types of information can be stored in different directories.

The logical arrangement of data will make the process of backup easy. The user can take a backup of a particular directory. The unnecessary files will not be included in the backup that will save time also.

 

2. Complete or Increment Backup

The user should decide what type of backup is better. Backup of all data on the hard disk is called complete backup. The advantage of this backup is that the entire hard disk is backed-up. It takes more time and storage capacity because the entire data of hard disk is copied.

Incremental backup creates a copy of only the data that is newly created or modified since the last backup. In this type of backup, the entire disk is not copied. It takes less time and space than complete backup.

 

3. Offsite Storage

The backup of data should not be stored on the same computer on which original data is stored. The backup should be stored offsite on separate media like CD, Zip disk, etc. It should be kept at safe locations. The reason is that if the computer is damaged, the data may be monitored by other media.

On the other hand, if the backup is stored on the same computer, it will be lost in case of any damage to the computer.

 

4. Backup Time

The user should decide the best time for taking backup of data. Normally, backup is taken at the end of the day when the daily work is complete. It ensures that all files created during the day are included in the backup.

 

5. Backup Media

An important strategy is the selection of backup media. The user should select the best and most reliable media for storing data backup. Different types of media are available. The selection of media depends on the nature and quantity of data to be backed up.

 

Security Attackers

Different types of people can attack the computer system by using different techniques. Some do it for money and some for enjoyment and thrill.

Crackers, Cyber Gangs, and Virus Authors

Many attackers are computer hobbyists and experts. They enjoy the unauthorized access as an intellectual game Different types of such hobbyists are as follows:

• Hackers: Hackers are computer hobbyists who enjoy pushing computer systems to their limits. They experiment with programs to try to discover undocumented features. These are the capabilities that are not mentioned in the systems manuals. They modify systems to obtain the maximum possible performance. Sometimes, they try to track down all the weaknesses and loopholes in systems security. When hackers attempt unauthorized access, they rarely damage data or steal assets. Hackers generally follow an unwritten code of conduct, called the hacker ethic that forbids the destruction of data.
• Cracker: Cracker is a computer user obsessed with gaining entry into highly secure computer systems. They generally do not harm or steal data, but the frequency and sophistication of their attacks cause major headaches for system administrators. Cracking is one form of computer addiction. They are obsessed with their reputation in the hacking and cracking communities.
• Cyber Gangs: Cyber gangs bring trackers together by means of the Internet and physical meetings. The group strengthens the immature and often destructive aims.
• Computer Virus Authors: Computer virus authors are the programmers who create computer viruses for computer systems. They, typically, are teenage males whose programming ability is much more developed than their ethical conscience.

• Security and Copyright