The risks to data:
The data stored in a computer can often be far more valuable than the actual
computer equipment. Losing such data could put a company out of business.
Examples of valuable data are:
- a company’s financial records;
- customers’ details;
- records of company stocks and shares;
- data collected from experiments or research.
Data can be damaged or destroyed in the following ways:
- mistakes by users such as deleting files
- hackers gaining access to systems and changing or deleting data
- computer fraud where data is changed to benefit individuals
- theft of computer hardware such as laptops with data on the hard disk(s)
- infection of systems and data by computer viruses.
- deliberate and malicious damage by users of the system, possible in
revenge for being made redundant for example.
- disasters such as fire, floods, earthquakes etc. destroying equipment
- breakdown of hardware, particularly disk drives
Why computer data is easier to misuse than paper-based
|Gaining access to the data
||Anonymous remote accessing using the Internet (hacking)
can be done if someone has the skills with a low risk of being caught.
||Someone would have to physically break into where the printed data is
|Making a copy of data and removing it
||Files can easily copied onto removable storage media (for example, a USB flash drive
which can easily be hidden and
Files could also be removed by being sent as an email attachment.
|Paper would have to photocopied or photographed. Large amounts of
photocopied pages could be
bulky to remove easily without detection.
|Altering data without being detected
||It is hard to spot altered data, even for an expert looking closely at the file
||It is usually easier to spot where printed data has been altered.
|Searching for valuable data
||It is easy and fast to search and sort computer data using software.
||It is very time consuming to search and sort pages of printed data.
Reducing the risks of data loss:
Making a backup of data:
Keeping hardware secure:
Protect the computer itself by using locks on doors and windows and using security bolts to fix the computer permanently to
- Laptops are often fitted with locking points so a cable can be used to
secure them to a desk etc.
- Floppy disks are easily physically damaged and must
also be kept
away from magnetic fields and dust.
Illegal access to computers:
Hacking involves unauthorised access to
computer systems, usually by finding out or breaking passwords. Once
into a computer system a hacker can do an enormous amount of damage. Stand-alone
computers are less of a risk as the damage is limited to just that computer. Computers which form part of
a network or those with external links, such
as attached modems, are at greater risk as they can be accessed from other
There are three levels of hacking, all of which are punishable by fines or
imprisonment under the Computer Misuse Act of 1990.
- Accessing information without permission -
viewing information (i.e. looking through someone's personal email)
or even attempting to access it is illegal.
- Accessing information and using it for illegal purposes
- the information that has been accessed is used by the hacker or passed to
someone else who uses it for illegal purposes (i.e. looking
up details of a rival companies research projects or using information for
Accessing information and
altering it for fraudulent purposes - the
hacker alters the information they have accessed in some way (i.e.
altering financial details of customers in a bank or introducing a virus)
Ways to restrict access:
- Using user Ids (user identification)
- Blocking external access - external hackers
can be blocked by disconnecting modems from the telephone line
when not being used. Systems with permanent phone connections need special
software called a 'firewall' to try and prevent unauthorised access over
networks and the Internet.
- Physically making a computer or network difficult to access - by
keeping individual computers in secure areas and blocking access to
removable media so data cannot easily be copied.
- Encryption - this involves transforming the data so that it is
unreadable without a digital key. Encrypted data is therefore meaningless if
it is accessed or intercepted. It is particularly important to encrypt
data transferred over wireless networks because the data is so easy to
There are three things to remember when
explaining what a virus:
- It is a program: a set of instructions which can be introduced into a computer via a floppy disk,
email attachment or the Internet.
- It makes copies of itself: the program contains instructions that
make it attach copies of itself to system files or programs. It
can therefore spread to other
programs on your hard disk and onto floppy disks or email itself to all the
contacts in your email address book.
- It causes damage: the effects can be devastating and cost
millions of pounds to fix. They can alter programs or files and
completely disable a computer's operating system.
Because a virus alters files it is illegal under the Computer Misuse Act of 1990 to deliberately infect a computer system with a virus and the offence
is punishable by fines or imprisonment in the same way as other hacking offences.
Protecting against computer viruses:
is usually required to detect
and then destroy them but it is important to have regular updates to deal with new
viruses. The anti-virus software scans the files on a computer looking for any
viruses which it then removes and alerts the user.
Protecting floppy disks - The 'write-protection' hole in the corner of the floppy disk
kept covered to prevent accidental wiping of the disk or the
introduction of viruses.
To reduce the risk:
use a floppy disk of memory stick given to you from an untrustworthy
source or pass floppy disks around between your friends.
- Do not start up a computer with a floppy disk left in the drive.
- Set the computer BIOS so the boot
sequence does not start with the floppy disk drive.
the write-protection hole covered on floppy disks that
are used to store original "clean" programs -
so they can be reinstalled with confidence.
- Never open an email
attachment that comes from someone unknown or is not clearly
explained in the email message that it is attached to. Even then BE
SUSPICIOUS - virus program writers are always thinking of new ways to get
computer users to open attachments and run the virus!
- Install a virus protection program and keep it up-to-date!
- Be careful of the websites you visit and the hyperlinks you click on.
Many websites are designed to trick visitors into downloading viruses, trojans
or spyware by offering free downloads. If you are unsure of a hyperlink, always hover over it with the
mouse before clicking so you can see (in the bottom-left of the browser
screen) where it will take you to. i.e.
here to view a funny video.