ASSIGMENT 17: INTRODUCTION COMPUTER THREATS

INTRODUCTION COMPUTER THREATS

The computer is a great tool to store important information. In certain

cases, the information is very vital that losing it will harm the computer

system.

Computer threats can come from many ways either from human or natural

disasters. For example, when someone is stealing your account information

from a trusted bank, this threat is considered as a human threat. However,

when your computer is soaked in heavy rain, then that is a natural disaster

threat.

MALICIOUS CODE

Malicious code is also known as a rogue program. It is

a threat to computing assets by causing undesired

effects in the programmer’s part. The effect is caused

by an agent, with the intention to cause damage.

The agent for malicious code is the writer of the code,

or any person who causes its distribution. There are

various kinds of malicious code. They include virus, Trojan horse, logic door,

trapdoor and backdoor, worm and many others.

a) VIRUS

· a program that can pass on the malicious

code to other programs by modifying them

· attaches itself to the program, usually files

with .doc, .xls and .exe extensions

· destroys or co-exists with the program

· can overtake the entire computing system and spread to other

systems

b) TROJAN HORSE

· a program which can perform useful and

unexpected action

· must be installed by users or intruders

before it can affect the system’s assets

· an example of a Trojan horse is the login script that requests for

users’ login ID and password

· the information is then used for malicious purposes

c) LOGIC BOMB

· logic bomb is a malicious code that goes off when a specific

condition occurs.

· an example of a logic bomb is the time bomb

· it goes off and causes threats at a specified time or date

e) TRAPDOOR OR BACKDOOR

· a feature in a program that allows

someone to access the program with

special privileges

f) WORM

· a program that copies and spreads itself

through a network

Primary Differences Between Worms And viruses

HACKER

Hacking is a source of threat to security in computer.

It is defined as unauthorised access to the computer

system by a hacker.

Hackers are persons who learn about the computer system in detail. They

write program referred to as hacks. Hackers may use a modem or cable to

hack the targeted computers.

NATURAL AND ENVIRONMENTAL THREATS

Computers are also threatened by natural or environmental disaster. Be it at

home, stores, offices and also automobiles.Examples of natural and

environmental disasters:

§ Flood

§ Fire

§ Earthquakes, storms and tornados

§ Excessive Heat

§ Inadequate Power Supply

Worm Virus

Operates through the network Spreads through any medium

Spreads copies of itself as a

standalone program

Spreads copies of itself as a

program that attaches to other

programs

THEFT

Two types of computer theft:

1) Computer is used to steal money, goods,

information and resources.

2) Stealing of computer, especially notebook and

PDAs.

Three approaches to prevent theft:

1) prevent access by using locks, smart-card or

password

2) prevent portability by restricting the hardware

from being moved

3) detect and guard all exits and record any

hardware transported

ASSIGMENT 16: COMPUTER SECURITY

COMPUTER SECURITY

DEFINITION OF COMPUTER SECURITY

Computer security means protecting our

computer systems and the information they

contain against unwanted access, damage,

destruction or modification.

We need to protect our computer from any

intruders such as hackers, crackers and script

kiddie.

We do not want strangers to read our e-mail, use our computer to

attack other systems, send forged e-mail from our computer, or examine

personal information stored on our computer such as financial statements.

TYPES OF COMPUTER SECURITY

Three types of computer security are:

a) hardware security

b) software security/data security

c) network security

a) HARDWARE SECURITY

Hardware security refers to security measures used

to protect the hardware specifically the computer

and its related documents.

The examples of security measures used to protect

the hardware include PC-locks, keyboard-locks,

smart cards and biometric devices.

b) SOFTWARE AND DATA SECURITY

Software and data security refers to the security

measures used to protect the software and the loss

of data files.

Examples of security measures used to protect the

software are activation code and serial number.

41

An example of security measure used to protect the loss of data files is the

disaster recovery plan method. The idea of this plan is to store data,

program and other important documents in a safe place that will not be

affected by any major destruction.

c) NETWORK SECURITY

The transfer of data through network has become a

common practice and the need to implement

network security has become significant.

Network security refers to security measures used

to protect the network system. One example of

network security measures is firewall. With firewall, network resources can

be protected from the outsiders.

PERSONAL COMPUTER SECURITY CHECKLIST

In order to make sure our computers are secured, here are the computer

security checklist to follow.

ü Do not eat, drink or smoke near the computer

ü Do not place the computer near open windows or doors

ü Do not subject the computer to extreme temperatures

ü Clean the equipment regularly

ü Place a cable lock on the computer

ü Use a surge protector

ü Store disks properly in a locked container

ü Maintain backup copies of all files

ü Stores copies of critical files off sites

ü Scan a floppy disk before you open it

ü Do not open any unknown email received.