Understanding Digital Communication Systems.

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13 Δεκ 2013 (πριν από 3 χρόνια και 7 μήνες)

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Kyfan Stevens

Understanding Digital Communication S


In this essay I will be investigating various communication protocols that are common and are in use
by a
huge percent of the population

I will be looking into what they are, who uses them and
are they used for

For example I will look into 3G (Third generation protocol) companies that use it

like O2 and why they use it.

World Wide Web Consortium (W3C)

The World Wide Web Consortium

is the main international standards agency for the World Wide

The consort
ium was founded by Tim Berners
Lee and

is still headed by him today

consortium is partnered with various other organisations that have now become members of W3,
there a
re in total 386 other member organisations within the consortium

consortiums focus

on keeping the World Wide Web running at its full potential, they act as an
overseer for the web as they implement new rules and help

promote accessibility internati
They formulate a structure and rules that all websites and organisations that use the web must

They are essentially the police for the web

hey manage and help improve the
fundamentals and key
elements of the web and keep it safe and
user friendly for all of us to use.

Wireless Access Protocol
or Wireless Application Protocol

Wireless access protocol is the term for a technical standard that receives and accesses information
over a wireless mobile network

An example of this would be a WAP browser which
is an internet
used on a mobile phone such as Google or Chrome

WAP was introduced ISP’s had
trouble creating and offering interactive data to their users, they needed WAP to allow content l
News, music downloads and stock exchange info to be available to people in an interactive and
engaging way.

People using smart phones and ta
blets use this technology daily

WAP has become commonplace
nowadays and we expect as users to see interesting

and interactive UI’s on our devices
and this is

because of WAP.

Global System for Mobile (GSM)

Global System for Mobile Communications, originally known as Groupe Special Mobile, is a standard
that was developed by ETSI the (European Telecommunic
ations Standards Institute)

It is used to
describe protocols the second generation of cellular networks used on mobile devices such as
mobile phones; this was the first digital network after the Analogue first generation

GSM was
introduced to phase o
ut obsolete analogue first generation technology (1G)

There have been improvements over time with the introduction of 3G, 3GPP and the recently
released 4G LTE Advanced standards.

Kyfan Stevens

Third Generation Protocols (3G)

Third Generation or 3G

as it is colloqu
ially known

is a term used to describe or represent the Third
Generation of Telecommunications technology

It is also known as TRI
Band 3G

This is yet another
set of standards used on Mobile devices and mobile Telecommunication services and networks
comply with IMT
2000 (Internatio
nal Mobile Telecommunications)
hese are specifications set by
the International Telecommunication Union

Telecommunication services such as O2 or Vodafone market 3G technology, this indicates that the
service is p
rovided over a Third Generation wireless network

Services that are advertised as being
3G have to meet regulations and standards set by the International Telecommunication Union

ome of
these standards are that they are r
equired to provide a peak rat
e of at least 200kbit/s which
is roughl
y 0.2mbit/s. Most providers out
do the minimum accepted requirements for a Third
Generation service.

Multimedia Messaging Service (MMS)

Multimedia Messaging Service or MMS as it is generally abbreviated is a generic
method of sending
messages that include Multimedia content to and from mobile devices

It is an extended version of
the earlier develop
ed SMS (Short Message Service).
SMS originally allowed users to communicate
by sending messages to one another but we
re only allowed to type the maximum of 160 characters.

The most popular use for MMS is to exchange photographs from camera equipped devices like an

or any other device nowadays. It is also a popular method of


media such as
videos, ringt
ones and text pages

This standard was developed by t
he Open Mobile Alliance (OMA). T
he OMA were originally part of
the 3GPP and WAP groups.

General Packet Radio Service (GPRS)

General Packet Radio Service
is a POMDS (Packet Orientated Mobile Data Ser
vice) on the Second
and Third generation cellular communication services Global System for Communications (GSM).

Originally standardised by the ETSI (European Telecommunication Standards Institute) GPRS was
created in resp
onse to earlier CDPD (Cellular Dig
ital Packet D
ata) and I
mode packet
cellular technologies.
GPRS is currently maintained by the Third Generation Partnership Project

GPRS is charged based on the amount of data that is transferred, which is contrary to the circuit
d data which is generally billed per minute used

GPRS can be
sold as a bundle

for example

5GB a month on a fixed fee basis, o
r on a pay as you go contract. I
f the user exceeds their limit the
provider may disallow any further data or the pro
vider ma
y charge the user per M
egabyte over their


Bluetooth is another form of wireless technology that allows its users to transfer data over short

It uses short
radio transmissions in the ISM form from 2400
2480 MHz from
Kyfan Stevens

mobile and fixed devices such as a Mac or PC

This creates PAN

Personal Area Networks

have a high level of security
This technology was created by telecommunications vendor Ericsson in

Bluetooth Technology is managed and overseen by S
IG (Bluetooth S
pecialist Interest Group), whose
members total
bove 17,000 member companies who

are in the fields of telecommunication,
computing, consumer electronics and networking

SIG observes and oversees the development of
the technology and helps
anage and qualify the programme and

it also protects trademarks

you want your product to be marketed as a Bluetooth device you have to be qualified to standard

defined and specified by SIG
Patents are required to implement the latter technology and are
licensed to qualifying devices.

Broadband ADSL (Asymmetric Digital Subscriber Line)

An Asymmetrical Digital Subscriber L
ine is a variant of subscriber line technology

ADSL enables a
ster connection and data transmission via copper telephone lines rather than using conventional
standards such as a
voice band


The technology does this by using frequencies that are not
being used by a voice telephone call

Splitters or DSL filt
ers are used to allow a single connection
that can be used for Phone or voice calls and ASDL services at the same time

ADSL can only
transmitted over a short distance

usually the last mile of connection
, from the
telephone exchange. T
his is typ
lly a distance of about 4km. I
t has been known to exceed this
and end up reaching a distance of about 8km.

Voiceover Internet Protocol



communication protocol that incorporates the technologies, methodologies and
transmission techniques

that are used to exchange voice and multimedia communication over an IP
(Internet Protocol) network

The Internet is an IP network.

VoIP is available on many mobile devices such as Smartphone’s and p
ortable devices such as an Ipad.
his is used so peop
le who are

t on a phone can still send SMS messages over 3G or a WI