DATA SECURITYData security refers to both physical protection of

data and the controlled access of information

The person who has good knowledge can steal the data, the person is called HACKER

Type of threats to Data Security1. Data not available to authorized personal at the

required time: Threat due to faulty system or virus infections

Preventive Measure: i. check the system and confirm whether it is faultyii. If data is infected by virus, the virus protection measure must be taken

2. Data becoming available to unauthorized personal : The data stolen by the Hackers

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Preventive Measure:

a. Identification : Authorized users are given an identity code called User id code to access the data

b. Authentication : The verification of a user’s identity by passwords.

c. Authorization: Determining how an authenticated user is permitted to use data.

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Cryptographic SecurityThe translation of data into secret codes to safe

guard or protect the data during transmission

Uses:To provide data confidentiality ( authentification

and authorization fail )

Encryption : process that translate data to secret code to protect it from intended user.

Decryption : process that translate encrypted data to plain text

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Encryption Process

DECRYPTION

Algorithm

ENCRYPTION

DATA (Plain Text)

SECRET CODE(Cipher Text)

Tran

sm

issio

n

Algorithm

DATA (Plain Text)

SECRET CODE(Cipher Text)

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Computer Virus

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Computer VirusWhat is Computer virus?

A program written to alter the way a computer operates, without permission or knowledge of the user

The Criteria to consider as Virus:i). It must be execute itselfii). It must replicate itself

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Classification of Virus

File Infector VirusesBoot Sector VirusesMaster Boot Record VirusesMulti-partite virusesMacro Viruses

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1. File Infector VirusesInfect the program files which have

executable code such as .com and .exe files

It infect other files in the computer when infected program is run from floppy, hard drive or from the networks.

Example: Jersulum, Zigzag, Yankee 46, Friday the

13th

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2. Boot Sector Viruses

It infect the system area of the disk (boot record on floppy disks and hard disks)

All floppy disks and hard disks contains small program in the boot record that run when the computer is start up. Boot sector viruses attach themselves to this part of the disk and activate when the user attempts to start up from the infected disk.

These virus are memory residentExample:

airCorp, Aragon

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3. Master Boot Record Viruses

Memory resident virus which infect the disk same as Boot Sector viruses (where viral code is located).

It save a legitimate (genuine) copy of the master boot record in a different location

Example:

AntiExe, NyB, Unashamed

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4. Multi-partite viruses (polypartite)

It infect both boot records and program file

Once infected, it is difficult to repair

Example:

One-Half, anthrax, Tequilla

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5. Macro Viruses

It infect data files and other files (advent of Visual Basic in Microsoft’s Office 97) especially Microsoft Office Word, Excel, PowerPoint and Access files

Example:

W97M, Cakes, XM, Yohimbe

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Trojan HorseProgram that infect files but does not

replicate itself

Contains malicious code when triggered cause loss of data

Example:PWSteal, Trojan

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Worm

Program that replicate itself from system to system without the user of host file.

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Anti-virus SoftwareIt scan the programs, detect viruses and remove

them

Example of Anti-Virus Software are:

McAffee, SmartDog, Norton Antivirus, Avast, Quick Heal, AVG, Avira Antivir, Spy Doctor, etc

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Prevention of VirusThe precautionary measure are:1. The use of pirated software should be stop2. Write protect tags should be used on the original

software diskettes.3. Proper back up of all data and program files should

be kept4. Used floppies should be reformatted5. Avoid letting the system to be used by unauthorized

users6. Restrict the use of outside floppies/CD/Thumb drives7. Do not leave a floppy disk in the floppy disk drive

when you shut or restart the computer.8. Do not set your e-mail program to auto run

attachment9. Obtain all Microsoft security updates10. Use computer virus scanning program

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The CureThe viruses are omnipotent. Viruses can be cured

with anti-viral programs. The anti-viral programs perform one or more of the following functions:

Prevention: Check the system and stop the virus from infecting

Detection: It detect the virus infected files in the systemVaccination: Inject some code into the executable files and

check on the program being executed and warns if any changes have been made

Inoculation : Insert the virus signature into the infected areas and perform self detection and does not infected already infected files

Identification : Identify the types of virus infected in the systems

Damage control : It helps to control the systems/ program from getting damageKinley's Lesson Notes for Class X- 2010 17

Health IssuesRSI (Repetitive Strain Injury)-occurs from repeated physical

movements doing damage to tendons, nerves, muscles and other soft tissues.

How to prevent RSI?

1. Correct typing technique and posture- wrist should not rest on anything while typing and rest your hands on the lap or side instead of leaving on the key board.

2. The right equipment set up- key boards and chair are set at thigh and forearms level and wrist are straight.

Ergonomics – Mismatch between the physical capacity of workers and the demands of job (Musculoskeletal Disorder [MSDs])

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Copy Right

It confirms the validly of copyrights attaching to consumer products

Authentication Feature : halogram, watermark certification symbol code, image, sequence of numbers or letters

Software PiracyMaking illegal copies of software and distributing them in original packagesKinley's Lesson Notes for Class X- 2010 19

Types of Piracy:End User Piracy: copying software without buying

the appropriate number of licensesHard Disk Loading: practice of installing

unauthorized copies of software onto computer hardware prior to scale ( Computer illegally install software to sell machines)

Internet Piracy: copyright material illegally distributed through the internet (online)

Bootlegging: illegally making and distributing copies of software commonly in the form of backup, CD-R etc.

Counterfeiting: illegally making of copies and distributing copies in packages made to appears as original.

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Consequences of Software Piracy

Serious crimePay finesBear legal action and criminal

prosecution

How to refrain from Copy Right Issues?

Avoiding Software piracyBuying legal software

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