Data Security and

Data Transfer

Sara Álvarez

Rita A. Puerta Jorge Ramirez

Juliana Revollo

DATA SECURITY

Data security is about keeping data safe. Many individuals, small businesses and major companies rely heavily on their computer systems

KEY THREATS TO DATA SECURITY

Data may get:

-lost or damaged during a system crash - especially one affecting the hard disk

corrupted as a result of faulty disks, disk drives, or power failures

-lost by accidentally deleting or overwriting files

-lost or become corrupted by computer viruses

-hacked into by unauthorized users and deleted or altered

-destroyed by natural disasters, acts of terrorism, or war

-deleted or altered by employees wishing to make money or take revenge on their employer

KEEPING DATA SECURE

Measures that can be taken to keep data secure include:

-making regular backups of files (backup copies should be stored in fireproof safes or in another building)

-protecting yourself against viruses by running anti-virus software

-using a system of passwords so that access to data is restricted

-safe storage of important files stored on removable disks, eg locked away in a fireproof and waterproof safe

-allowing only authorised staff into certain computer areas, eg by controlling entry to these areas by means of ID cards or magnetic swipe cards

-always logging off or turning terminals off and if possible locking them

-avoiding accidental deletion of files by write-protecting disks

-using data encryption techniques to code data so that itmakes no apparent sense

Data Transfer

Transfer of data files containing pictures (graphics), text, sound, or numbers is possible from one computer to another, one make of hardware to another, and one application to another. This is possible because standard file types and data formats have been developed.

Data does not need to be transfered on physical media, it can be transmitted at rapid speeds around the globe.

DATA FILE TYPES

Data files are stored in a number of formats, the formats depend on which application created the file to begin with.

For example, Microsoft Word stores files as *.doc but Adobe Photoshop stores files in a different format - *.psd.

The file extension identifies the file's format.

When data is transferred from one computer to another, the computer receiving the data file may not be able to read the format without the right application installed.

For example, an image created in Adobe Photoshop and saved as a *.psd file (Photoshop's format) would not be readable by Microsoft Paint.

TRANSLATING BETWEEN FILE TYPES

Data can be stored temporarily in a computer's RAM as a means of transfer from one application to another. In Microsoft operating systems this feature is called the clipboard and it can copy data from one application and paste it into another. Nearly all other operating systems support this functionality.

For example you can create a graph using a spreadsheet application and then use the clipboard to copy the graph to a desktop publishing application.

Limitations:

-Certain elements of one document may not be copiable to another application, eg video.

-Some file features (eg text layout and formatting) may be lost in the translation to a different format.

RAPID TRANSFER OF DATA

Files can be easily transferred and shared across the globe using the Internet. A file could be:

emailed as an attachment

sent over instant messenger

downloaded from a website/web server

accessed over a private network

IMPORT AND EXPORT

1.Export saves the file in a format that's readable by other applications.

2.Import opens a file created in another application for viewing or editing.

The need to import and export data files has led to the development of several standard file types that many applications can understand.

Examples are jpg and gif files for images, and mp3 files for sound; but there are also standard file types for text, movies, and spreadsheet data.

Often an application of a different type can import data, for example, a word processor may be able to import a spreadsheet file.

XML FILES

Recently program developers have started to use the XML web page file format as the standard way to store data. Files can be read by any browser on any computer, making it very easy to transfer data between computers.

Other standard file types, such as zip and pdf (portable document format), have been developed as ways of distributing data in the most efficient way possible. They do this by compressing it using zip technology or making it possible to read using a freely available downloaded reader application, as is the case with PDF files.

Bibliography

http://www.bbc.co.uk/schools/gcsebitesize/ict/databases/6datasecurityrev1.shtml

http://www.bbc.co.uk/schools/gcsebitesize/ict/databases/datatransferrev1.shtml