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Data Security


Importance of Securing Data

Data Security means ensuring that the data is free from any type of corruption and the access to this data is controlled in such away that only authorized users can access the data. Data refers to personal information regarding the individuals, bank details, etc. Hence, there is a need for everyone to secure the data so that it does not fall into the hands of unauthorized users.


Different Methods of Securing Data

There are different types of data to be secured. The procedure regarding how to secure different types of data is given below:

Shared Information


Make sure that the shared information is accessed by the authorized users and also specify the data that should be shared and data that should not be shared by the public.


Securing Data While Transmission


Securing the data while transmitting includes encryption and authentication and also the end-to-end users are authorized.

·Authentication is secret information that is shared between two computers before the actual communication starts. Public key encryption is another means of authentication which authenticates only the receiver and not the sender with the help of the keys which are possessed by the two systems by other means.

·Encrypting data with out a key can be easily accessed by modern computer users by performing brute force attack. So in order to protect the encrypted data the key length should be long such a way that it is not easy to guess it. Encrypting the data only ensures that the data cannot be read by the third party in an understandable format when the data has been received by them.

·Securing through Web Browser.
Ensure that the data being sent using browser application is secured by

seeing theURL. Ensure that it is using HTTPS instead of HTTP
in the URL for authentication.

·Secure Email Programs.
Secure email programs use public key encryption for sending and
receiving messages. This works well when both the users are using secure

email programs otherwise the user should send emails without using

secure email programs.

·Secure Shell.
Previously computer users used telnet application to connect to remote

systems.But telnet transfers the information in clear text. To avoid this

problem 'Secure shell' has been introduced which sends the data in the

encrypted form. It uses public key cryptography for encryption and also
ensures confidentiality and data integrity.


Data Backup


Another method of securing the data is by taking the backup of the original data in to another disk or tape. This backup helps the users to retrieve the original data in case of hard disk failures.

Securing Data by Secure Deletion

When the data which user does not require any more is deleted, care should be taken while deleting the data so that the data can not be reconstructed by an unauthorized person. Deleting the information and formatting does not ensure that the data is safely deleted.

In order to delete the data permanently, some software tools are available which will prevent the data from being reconstructed. Some operating systems allow formatting command in such a way that it not only formats but also adds zero in to that place. The easiest way of deleting the data is by using wiping program which not only formats the disk but also adds some garbage data in to it.

There are several algorithms available for secure deletion or disposal.

·Single Pass
Here the data is overwritten with 1's and 0's for only one time.

·DoD 5520.22-M Standard
This standard overwrites the addressable locations with characters

and its Complements and compares it with other.

·Guttmann Method
This method overwrites the data for nearly 35 times and this will be

done by taking in to the account various encoding algorithms used

by various disk manufacturers.


Linux and Unix systems implement a file destruction command to protect files that contain sensitive content from being recovered by someone else. The 'shred' command overwrite the specified files repeatedly, in order to make it harder for even very expensive hardware probing to recover the data. It additionally provides the feature to shred and then delete a file from the hard disk.

Another Linux/Unix command that can be used to format a disk drive completely is the 'dd' command. When certain switches to this command are used, the entire disk is rewritten to zeros.

Tools are available at the following links:

http://dban.sourceforge.net

http://www.heidi.ie/eraser

http://micro2000.com/erasedisk

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