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Security And Integrity Of Data Essay Research

Paper

Security

of data Security of data

involves the protection of data from anything that could destroy it, or

introduce errors to it, as this may corrupt data. Things

such as hazards, for example fires and floods, or another person gaining access

to the data and damaging it, can destroy data. The

security of data is very important, as many people store extremely important

documents on their computers, for example bank or health records which may

contain personal and confidential information about a person, which when

discovered could cause major problems. If somebody were to discover another

persons bank details through data being insecure, money could be taken from

their account, which would cause confusion and disruption for everybody. Data

does need to be kept secure, and there are many ways to do this, for example by

backing up data or putting passwords on your files. How data and

software can sometimes not be secureThere

are a large number of ways in which data and software cannot be secure, in some

of the following situations:·

Files can be

accidentally overwritten or deleted because of: Ё

Fraud Ё

Accident Ё

Files could have the

wrong data inputted·

They

could be lost due to: Ё

Losing discs Ё

Damage to the hard

drive Ё

Files or discs

destroyed·

Deletion or

corruption Ё

Discs could be

scratched Ё

Viruses Ё

The files could be

accessed and damaged by unauthorised users; this could be due to you not having

necessary password protection on your PC. Hackers and viruses Hacking

is gaining access to a computer system without authority, usually to cause some

damage to the system, or to gain information that would not usually be

available to the general public. People that do this could delete or corrupt

data, and copy it for themselves to use for their own reasons. Hackers are the

people that attempt to do this. Hackers once gaining entry to a system are

presented with unlimited options as to how they could damage the system. They

could simply copy files, delete them, or bring down the entire system.

Protecting a system against hackers has become an extremely important subject,

since there is no end to the damage that can be done. A virus is a program

which when ran would usually attempt to disrupt the use of your computer in

some way. Viruses can be written to do many things, from displaying messages on

your computer screen to allowing another person unauthorised access to your

computer to deleting files from your computer. Nowadays, a very

common way of spreading viruses is through the Internet. People often send

viruses through e-mail, which unsuspecting people then open and damage is

caused to their computer. Many viruses sent through e-mail now have the ability

to forward themselves to everybody in the recipients address book, meaning they

spread more quickly and to a larger amount of people. A virus that has been in

the news fairly recently was the ?lovebug? virus, spread through e-mail it

would copy and forward itself to every person in every recipients address book

before causing some damage the computer. Protection from

hackers and viruses There

are a large number of ways in that an organisation can be protected from

hackers and viruses: ·

Using

anti virus software ? There are a lot of different anti virus programs

available, which when loaded onto your computer can scan the memory and discs

for any viruses that could be potentially harmful to your computer. The

software would then remove any viruses found. However it is important to

regularly update your virus software, as new viruses are being discovered all

the time which old pieces of software may not be programmed to check for. ·

Stopping people

downloading files/placing files from discs onto the hard drive of the computer

? This would be a very effective way of preventing viruses, as no unauthorised

or potentially damaging software would be allowed onto the computer, as long as

people did keep to the rules. ·

Backing

up the system daily ? This wouldn?t necessarily stop viruses within the system,

but in the event of the system being destroyed then it would be easy to quickly

replace everything that has been lost as it would be backed up on discs. ·

Have

one stand alone PC where discs can be checked for viruses, therefore if there

happens to be a virus on the disc it will only affect the one PC and not bring

a whole network down. ·

Using

user names and passwords that are unique. Therefore nobody would be able to

access the system without authorisation since they would not know these pieces

of information. ·

Setting

up a firewall on the system. This is a device that would monitor the ports of

your computer and block unauthorised access. It can keep track of all data that

enters or leaves your network, and even stop this data from doing so, therefore

if you did get a virus on your computer you would have monitored when it was

received and where it came from. Backing up dataData needs to be

backed up regularly. This is so that if the data is ever lost due to a virus,

or accidental deletion, loss or corruption, it can easily be replaced. This

would save a lot of time in re-producing all of the lost data, and if data were

backed up every evening then it would only be one days work maximum that would

ever be lost in the event of one of the above happening. Even

if your PC is password protected it can still be hacked, and files lost this

way as many programs make this process very easy. You can help to keep

your data safer by backing up data every time you save a piece of work. You can

back up data onto either floppy discs or if you have a CD writer, onto CDs. If

you back up onto re-writeable CDs then you can overwrite these backups once you

add to your work. Physical safeguards Some

of the following physical safeguards could be used to look after data: ·

Files locked

away/discs kept in a locked room ·

Write protect floppy

discs, this involves moving a small tab so that data cannot be written onto the

disc. ·

The small tab that is

on tape cartridges can be snapped off which will prevent data from being over

written. ·

The computer could be

password protected so that nobody without the correct password would be able to

use the computer ·

Peripherals such as

the mouse or the keyboard could be removed, which would prevent anybody from

using the machine unless they had spares with them, which would be unlikely. Safeguarding the

network An

organisation could safeguard its network from who used it by: ·

Using firewalls ?

These could be used to stop data coming into and going out of the network.

Therefore hackers would not be able to gain access to the network, as the firewall

would stop them. ·

Give every person

that is going to use the network a unique username and password. Then anybody

that didn?t know the passwords would be unable to gain entry to the network.

Also the server administration could allow different people access to different

things throughout the network to limit and track damage that could be done. Passwords Passwords

are used to limit who can gain access to a computer.? For a password to be effective it would have to be changed

regularly and be difficult for another person to guess. However there are

programs that can guess passwords very quickly through word lists that are

programmed into them. To combat this the number of attempts there can be at

entering the password can be limited. For example, on the

school network each pupil has a separate folder with a unique username and

their own password. If anybody tries to gain unauthorised access to a folder

placed on the network they would first need to know a username, and a password

that goes with it, finding these could be a difficult task. Integrity of data Data

can become inaccurate in some of the following ways: ·

Mistakes in

collecting data ·

Transmission errors ?

These types of errors would occur when data, which has been sent from one

device to another, is changed during transmission due to a hardware

failure.? For example files being sent

across the Internet from one computer to another may become corrupt through

sending, which would render them unusable. ·

Read errors ? When

data is misread. ·

Transcription errors

? These are errors that are made whilst the data is being entered, for example

people simply making a typing error and not realising. The

consequences of inaccurate data could be that, in the example of a company such

as a bank having wrong data, their customers becoming annoyed, and the company

losing money. The company could also be arrested under the data protection act. Verification,

validation and input masksVerification is when

a human, through proofreading, checks data. You can do this in several ways: ·

Proof read the work

on the monitor or on a print out ·

Check work on a

monitor/print out with a manual copy ·

Get somebody else to

check the work for you. ·

Two people typing in

the same data, and if the data is the same it is accepted for processing. The

only drawback to this is the unlikely event that the two people actually make

the same mistake, and the wrong data is inputted.The advantages of

verification are that data is less likely to be inaccurate. For many companies

such as banks, data being accurate is crucial. However, it does take

time to check all the data, and in cases such as having two people entering the

data, this is using another person that could be doing other more important

work, and two wages need to be paid which would lose money.Validation

can be used in a database, where you set up the fields in a database so that

only certain information can be entered. It?s a check by the actual computer

program and makes sure that the data is allowable. There

are many different checks that can be performed: ·

Character

type check ? This check will make sure that the correct characters are entered

into the computer. ·

Length

check ? Where the length of the word that has been entered is checked, and if

this is incorrect an error message is displayed. For example when filling in a

form, if the question ?what sex are you? was asked, there are only two possible

answers, male or female, so we know that the maximum number of letters that

could be entered into this field would be 6. ·

Range

check ? You can perform this check on number, to make sure that they are within

a certain range. For example, upon entering peoples ages, there are not likely

to be any people older than 130, so you could set it up so that this anything

higher than this number could not be inputted. ·

Presence

check ? When a code is entered that checks if there is actually something in

the field. This would be used in a field which must have some data entered into

it, such as a primary key field which would define each entry into the

database. ·

List

check ? This only allows certain data to be entered. For example, ?Title.? We

know that there are only a certain amount of titles which could be entered, Mr,

Mrs, Miss, etc. So we could enter them all into the computer, and if anything

else was entered an error message would be displayed and the data could not be

entered.The

advantages of validation: ·

There

is less chance of making typing errors as the computer checks all your data for

you, and you do not have to look through the document so carefully for errors,

therefore this is a timesaver.Disadvantages: ·

Validation

rules can take a little time to set up. ·

They

also do not guard against typing errors completely.Input

masks allow you to actually design the way that data should be entered into

certain fields. Data can be entered exactly how you wish it to be, with

capital letters, or brackets, or percentage signs. The

advantages of input masks are that: ·

They

allow data to be entered quickly, you would not have to keep pressing the shift

key for capital letters if you set up input masks to capitalise in certain

places. ·

All

of the data will be accurate and consistent, providing you set up the input

masks correctly, as the input masks will make sure that all of the data is the same. ·

You

do not need to waste time checking all of the data, as it is certain that it

will all be correct.The

disadvantages of input masks are: ·

When

entering names, you could set it up so that the first letter of the 1st

name, and the 1st letter of the surname are capitalised. However

when it comes to names such as McHugh, the check would not allow the third

letter of this name to be capitalised. ·

Like

validation rules, they can take a considerable amount of time to set up; time

that could be better spent doing other things.The

following characters can be used to set up input masks. 0

? A number required 9

? A number optional L

? Letter must be entered ? ? A letter optional. > – A capital letter < – A lowercase letterIf you wanted to set an input mask up for a postcode, you

would do so in the following manner: An example of a postcode may be CW5 6JY. The input mask for this would be LL09 0LL The ?Ls? for capital letters, and the 9 would be there since

some postcodes do have an extra number on the end, but not all therefore the

number would be optional.




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