Revision-Guide Demetrios Ioannou - Kidblog

pigsabusiveElectronics - Devices

Nov 29, 2013 (4 years and 7 months ago)


Revision Guide

By Demetrios Ioannou

Advantages of


You can move around but still stay connected

Neat and clean, no untidy cables


Those without a great deal of networking experience can set up a
wireless network

Disadvantages of


The potential for radio interference due to weather, other wireless devices,
or obstructions like walls


The biggest drawback of setting up a wireless home network. It is still
fairly expensive to go wireless but costs have been gradually decreasing as
new technologies are on the rise


If one major section breaks down, for example the Rou
ter, the
whole network will be affected

Advantages of


The equipment is inexpensive.

Tend to be more secure

Many computers have a wired network adapter

Wired networks transfer information more swiftly

Wired networks are generally more
secure than wireless networks

Disadvantages of


Running the wires from each room within the home can be a difficult task
with holes needing to be drilled in walls.

Network cables can look disorganised

Network cables can disconnect or becom
e faulty consequently causing the
connection to fail.

Wireless encryption


scrambling the data so that it cannot be understood without the
number key that was used to encrypt it.

nline Forms

Advantages of online forms

An advantage of using

online forms is a form doesn’t have to be delivered or
a person has to go in.

Most online forms are quick and easy to fill in so it’s quick.

Most of them are safe so you don’t really have to be worried but in doubt
check out the page.

Disadvantages of
online forms

our information

can be sold

They can spam your email

Poorly constructed forms or application system e.g. you may not be able to
make changes to earlier answers, or the boxes for your text may not be big

Instructions can be poor and c
onfusing e.g. for the elderly because they
won’t know how to use a computer

You might lose the lot if you’re unlucky, some systems won’t let you save or
print a copy to keep.

You might have no opportunity to explain things which are important, such as
ng a different type of entry qualification, being a mature student, having
a disability, or having poor exam results.

What is data validation?

Data validation is used to keep everything in the same format.

Data validation can disallow the use of numbers i
n a particular field or entry.

This allows

xcel spread sheet formulas or other systems
r to function without error as the data is correct.

This gives the creator the ability to dictate how the user will input data to
make their systems

function properly.

Data Validation in an online form.

Data validation is vital for most online forms that have back ends (where the
data is processed by the company). These include Facebook's signup process
or Tesco's ordering forms.

This allows the
system to function without someone having to vet the data
and take out errors.


Global Positioning System

This is a system commonly used by driver / truckers to help navigate from one
place to another. It relies on a GPS device receiving signals from at least 3

to determine the position of the device (or car / truck) on the planet. It
can measure th
e speed, height, direction of travel.

Radio Frequency Identification


The RFID device can be used for animal tracking tags, credit cards and a
variety of items or

it is essentially works like a bar code.


The RFID device can be used to
identify a certain item or object for
example if a credit card RFID is scanned it will identify that it is your credit
card specific credit card and who it belongs to.


FRID devices are used in shop security tags.

Data Protection


The Data Protection Act (DPA) is a law designed to protect personal

stored on computers or in an organised paper filing system.

Information Commissioner

This is the individual responsible for enforcing the Data Protection Act

Data Controller

company or an individual within a company/organisation that is responsible for
collecting and storing data about people. They determine how the personal data is
going to be used.

Data Subject

These are the people that give their own personal details to the

data controller.

For example, a dentist’s patient giving them their home address and contact details.

Copyright, designs and patents act

Copyright applies to art, music, literature, poetry, films and the like (and also
computer software).

Rights apply to product design.

Patents cover inventions that satisfy certain criteria. The inventions could be
electrical, mechanical or a way of doing things or a new chemical compound
such as a drug.

The act means you cannot use pictures of famous
people for your own personal gain
without their permission.

The act means you can’t (shouldn’t) copy music without
the artist permission.

Not allowed to give a copy to a friend

Not allowed to make and sell copies.

Not allowed to use a software on a netw
ork (unless the licence allows you to)

Not allowed to rent the software without the permission of the copyright


Data security is about keeping data safe. Many individuals, small businesses and
major companies

rely heavily on their computer systems. It is important to keep data

Data may get:

Key threats to data security;

lost or damaged during a system crash

especially one affecting the hard disk

corrupted as a result of faulty disks, disk drives, or power failures

lost by accidentally deleting or overwriting files

lost or become corrupted by computer viruses

hacked into by unauthorised users and deleted or altered

destroyed by natural disaster
s, acts of terrorism, or war

deleted or altered by employees wishing to make money or take revenge on
their employer

Data Types


eg 1042


eg Mr Hughes


eg 24/12/13