.png)
Computer Security / Cyber
Security
Computer security refers to protecting computer and its
content from damage, theft or misuse and action to prevent such incidents.
Computer security includes security of data and
information strored and being transferred, computer programs and applications
and computer hardware.
Types of
computer security
· Hardware security
· Software security.
Information Security (infosec)
Information
security is the practice of preventing unauthorized access, use, disclosure,
modification, recording or destruction of information.
Key principles of Information
Security
a)
Confidentiality:-
Only authorized users can access the data resources and information.
b)
Integrity:-
Only authorized users should be able to modify the data when needed.
c)
Availability:-
Data should be available to users when needed.
We can protect our data by
· by periodically
checking the hard disk and replacing it if it shows failure symptoms
· by copying the
data in another disk in the system to avoid accidentally erasing or erasing
data by unauthorized person.
· we can copy
important data into online storage devices which is also called cloud storage
like Dropbox, Google Drive, iCloud, OneDrive etc.
· We can also,
sometimes, send important files as an attachment to our own mail such as Gmail
or Hotmail.
· Another issue of
protecting data is preventing them from authorized access. Unauthorized users
may access our data store in our computer in the cloud storage. To prevent our
data from unauthorized access we have to protect the storage space, folder or
file with password.
Security Threats
—
A
risk which can potentially harm computer systems and organization.
—
The cause could be physical such as someone
stealing a computer that contains vital data.
—
The
cause could also be non-physical such as a virus attack.
Possible Security Threats
Phishing is the
fake attempt to obtain sensitive information such as usernames, passwords and
credit card details by disguising oneself as a trustworthy entity in an
electronic communication.
A botnet is a
logical collection of Internet-connected devices such as computers, smartphones
or internet of things (IoT) devices whose security have been breached and
control is given away to a third party.
A rootkit is a
malicious code (kit) that hides in system area provides continued
Administrator's (root) privileged access to a computer while actively hiding
its presence.
Keylogger is
hardware or software for recording the keys pressed on a keyboard secretly so
that person using the keyboard does not know that their actions are being
monitored.
A computer hacker
is any skilled computer expert who uses his/her technical knowledge to overcome
a problem.
Malicious code (Malware)
Malicious code is
a kind of harmful computer code or web script that is planned to cause
undesired effects to damage a system.
Types of malware
a)
A
computer virus is a destructive program that copies itself and infects a PC,
spreading from one file to another, and then from one PC to another when the
files are copied or shared.
Some viruses
produce unnecessary messages on the screen, some virus hide files, some virus
corrupt files and programs, some virus reduce memory size, etc.
Computer viruses
can spread from one computer to other computers through sharing of infected
portable disk like pendrive, opening a virus infected email, messages or
attached files and downloading files and programs form the websites which are
not secure.
b)
Computer
worms use the network to send copies of themselves to other PCs, usually
utilizing a security hole to travel from one host to the next, often
automatically without user intervention.
c)
Trojan
horses are applications that look like they are doing something harmless, but
secretly have malicious code that does something else.
d)
Spyware
is any software installed on user’s PC
that collects your information without user’s knowledge
e)
Adware
is a software application used by companies for marketing purposes; advertising
banners are displayed while any program is running.
Security
mechanisms
—
A
mechanism that is designed to detect, prevent, or recover from a security
attack.
—
It
includes
—
Authentication
Systems
—
Firewalls
—
Cryptography
—
Antivirus
Software
—
Backup
System
Authentication System
—
The
process of identifying an individual usually based on a username and password
is called an authentication system.
—
Authentication
system makes sure that right people enters the system and access the right
information.
—
Types
of Authentication
Password Biometric
Password
—
A
password is a string of characters including letters, digits, or other symbols which
confirms the identity of a user.
—
Password
secures the data by protecting the data from unauthorized access.
—
We
have to keep the password secure and strong so that unauthorized users may not
gain access to the resource and misuse it with our identity.
Following
are some of the tips to make password secure and strong:
l Never share your credentials
online.
l Don't use easily guessable the
name of a pet, child, family member, birthdays, birthplace, name of a favourite
holiday.
l Don't use a sequence like abcd or
1234 which are, again, easily guessable.
l Mix characters, numbers and
symbols. Also, mix small and capital letters.
l Avoid using the same password in
all applications.
l Change password periodically
Biometric
· Biometrics are
physical or behavioral human characteristics that can be used to digitally
identify a person to grant access to systems, devices or data.
· E.g., fingerprints,
facial patterns and voice.
Firewall
A firewall is the network security systems that monitors and controls the
traffic flow between the Internet and private network on the basis of a set of
user-defined rules.
Firewall blocks
unwanted traffic as well as malicious software from infecting your computer.
Cryptography
—
Cryptography is the study of secure communications
techniques that allow only the sender and intended recipient of a message to
view its contents.
—
Cryptography
is used to secure and protect data during communication.
Types of
Cryptograpy
Encryption
Decryption
Encryption
—
Encryption
is the technology to encode file or message that is being stored or transferred
online in intelligible content which cannot be used by an unauthorized person.
—
Encryption
is done by the person who is sending the data to the destination
Decryption
—
The
conversion of encrypted data into its original form is decryption.
—
Decryption
is done at the person who is receiving the data
Antivirus software
—
Antivirus
software is software designed to detect and remove virus from computer system
and ensures virus free environment.
—
E.g.
Kaspersky, NAV, MSAV, McAfee, NOD 32 etc.
Backup system
· Backup is the system of copying data and programs into
another location or creating a duplicate copy of it in a secured place.
· Backup is vital to computer security system in order
to save the data from being lost or damaged due to accidental or intentional
harm. When data and software are lost or damaged, we can easily recover through
backup.
Hardware Security
Hardware security
is the protection given to the various hardware tools and equipment used in
computer system from the accidental or intentional harm.
Different
hardware security measures are:
a)
Regular
Maintenance
b)
Insurance
c)
Dust
free environment
d)
Protection
from Fire
e)
Protection
from Thief
f)
Air
condition system
g)
Power
Protection device (Volt guard, Spike guard, UPS)
Regular Maintenance
Computer system
need regular maintenance to keep the computer hardware in good working
condition and it also helps to find out problems in hardware and correct the
problems before they cause several damages.
Insurance
· A means of
protection from financial loss.
· If a computer is
damaged or stolen or any kind of harm done then we can claim for the insurance
amount and get the economic support.
Dust Free Environment
· Dust particles can
cause the failure of hardware components.
· Computer room
should be absolutely free from dust and air pollution.
Protection from Fire
· Due to faulty
wiring, loose connection, smoking in the computer room and overload on power
socket can cause fire in a room.
· Using fire alarms,
fire doors, fire detectors and fire extinguishers can minimize the damage of
hardware components and loss of information from fire.
Protection from Theft
The computer room
should have physical security with proper locking system, controlled access of
authorized persons only by having human guard or biometric machine.
Air Condition System
A system for
controlling the temperature and humidity (wetness) of the air
Maintains suitable
temperature or humidity in the computer room.
Room Temperature
should be maintained between 210C to 240C.
Power Protection Device
An electric device
that controls electric voltage and provides enough backup to the computer
system when there is power failure.
Computer needs 220
volts to 240 volts constantly.
Some common power
protection devices are:
a)
UPS
b)
Volt
Guard
c)
CVT
(Constant Voltage Transformer)
d)
Spike
Guard
e)
Surge
Suppressor
Why Power Protection Device
needed?
To protect
computer system from damage, expensive data loss and unnecessary down time (is
out of action or unavailable for use).
Volt Guard
A power protection
device that provides constant output voltage to the computer system in case of
high input voltage coming from the source.
UPS (Uninterruptible Power
Supply)
· UPS is a battery
supported power protection device which controls the electric voltage and
supplies clean and continuous power to the computer system even during power
failures.
· The importance of UPS in computer security system is that
it controls fluctuation of electric voltage and provides enough backup electric
power to the computer system when there is power failure.
Spike Guard
A device designed
to protect electrical devices from voltage spikes.
Automatically maintains a constant voltage level.
Software security
The
security given to the software and data from being lost or damaged due to
accidental or intentional harm is called software security.
Some of the software security
measures
a)
Backup
b)
Scandisk
c)
Password
d)
Antivirus
Scan disk
Scan disk is a
process which involves in maintaining the disk files and folders, bad sectors,
lost clusters, lost chains and other errors of the specific disk and it can fix
them if it is possible.
.png)