COMPUTER SECURITY AND DATA PRIVACY
COMPUTER CRIME AND ABUSE
Computer crime is committing of illegal acts through use of a computer or against a
computer. Computers have given new opportunities to commit crimes and are the targets
of crimes
THREATS TO DATA STORED ON COMPUTER

Natural disaster – fire, flood, earthquake or faulty equipment leading to loss of data

Theft of data – unauthorised persons who break into your computer system and steal
ideas or other sensitive information about your business

Hackers – persons that attack your computer system simply because they can. They
may have some malicious intent or just the thrill of breaking into the system

‘Spyware’ – rogue websites that gather information about you when you surf the web
and pry into your computer system remotely trying to do damage. Track your
activities and may place advertisements etc that pop up on your computer. Can also
put programs on your computer that can damage it

Computer viruses – over 100 new viruses are released on the computer world each
week. The internet allows viruses to travel around networks very quickly and do a
lot of damage
The Internet has made PC security a much bigger problem.
Security measures need to be put in place to keep both your hardware and software safe
HARDWARE SECURITY
Concerned with the physical hardware. This is the easiest to secure as PC’s can be
anchored to desks, rooms locked and surveillance systems put in place
Physical access to computer systems can be limited to certain persons
Reasonable safeguards need to be put in place against fire and other preventable disasters
Surge protectors should be used in case of electrical storms etc to prevent hardware
damage
SOFTWARE SECURITY
It is much more difficult to secure data and software in today’s distributed, networked
environment.
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Computer Security and Privacy
STEPS TO PROTECT DATA AND SOFTWARE
Backup Procedures
Use frequent backup procedures and keep backed up files in a safe place (often in a
different building). Regular backup means that it will not take long to update files again
from the latest backup. Often the documents to update the files are still available so the
system can be recovered quickly
Data Encryption
You can make your data unreadable to anybody except other trusted individuals.
Encryption lets you scramble messages and only the person with the proper ‘key’ can
unscramble them. This is particularly relevant to data that is transmitted over a network
Email and other messages on the internet can be encrypted using Public Key Encryption
which is a well recognised system of encrypting messages. The system is called Public Key
Infrastructure (PKI)
PKI uses software where each user has a ‘private’ key and a ‘public’ key. [These are codes
used to encrypt and decrypt messages]
The sender of a message encrypts the message with the recipients ‘public’ key and the
recipient decrypts it with his/her ‘private’ key. The parties to the communication can use
the email software of choice but each must use the same encryption software
Use of passwords
A common method of preventing unauthorised access to data and files is through
passwords. Passwords should not be easy to break. The problem is that people tend to use
words such as children’s or pet’s names
Passwords should be changed frequently
Passwords should not be written down
Passwords should be kept secret
Digital signatures and certificates
Used to ensure the ‘identity’ of sender and/or recipient. Public key technology can
guarantee that the sender of a message is who they say they are. A digital signature a
registered ‘identity’ like a passport and identifies the sender/recipient of a message
Protect against Viruses
Viruses are pest programs written to show off, to get revenge, to sabotage, for reasons of
intellectual curiosity or because of a desire for notoriety
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Computer Security and Privacy
A worm is a computer program that transfers itself from computer to computer over a
network.
A virus is a set of illicit instructions that gets passed to other programs or documents that
it comes in contact with. It can change or delete files or produce strange screen effects
Viruses can be passed on by disks, over a network or through email attachments but cannot
be spread by just reading an email or data file. Viruses are usually executable files (.exe
files)
The best way to secure your data against this type of attack is to use a reputable anti-virus
software package and keep it up-to-date. Never open an email attachment if you do not
know the sender
Personal Data Security
When you visit a web site it often leaves behind information on your hard disk in
anticipation or your next visit. These files are called ‘cookies’ and are often harmless.
Some sites will not respond well with cookies switched off (an option you can set in your
web browser software) so disabling them may not be possible. You can delete cookies
from your hard disk, provided you know where they are stored. You can also invest in
software to ‘manage’ your cookies
When you visit a website you leave a trail in the Internet History folder and the Temporary
Internet folder that tells what sites you have visited
The best way to secure your privacy is not to fill in online forms, fill out surveys, give your
email address or credit card information on the internet, unless you are sure of who you
are giving it to
Spam is the name given to unsolicited (junk) email messages. Filter software can be used
to stop them before they reach your mailbox
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Computer Security and Privacy