CO 874: Assignment-01
Achal Lekhi (al333@kent.ac.uk)
BROADBAND IN THE HOME
A building company, called “quick build homes”, is planning a new executive housing
estate. The houses are expensive, and each home contains a separate room laid out as a
home office. The builders are keen to make the houses as marketable as possible, and
because of this have decided to provide each house with a permanently-active connection
to the internet. They have yet to make a decision as to which would be the best way to do
this, and have invited several companies to make proposals so they can pick the most
favourable solution.
According to the above proposal, there are three best contenders for the plan i.e. first is
ADSL second is VDSL and third is WiMax. As the houses consist of a separate room for the
office i.e. office cum home so the services provide to them should be equally considered.
As the above scenario VDSL is the best technology to implement.
Overview
VDSL-(Very-high-bit-rate digital subscriber line) it’s a DSL (Digital Subscriber Line)
technology which provide fast transmission of data over a copper wire cable as a physical
medium. Both symmetric and asymmetric data flows are supported providing increased
flexibility and meeting the goals of applications, it is a digital data transport technology.
Copper wire can be untwisted or twisted pair (up to 52 Mbit/s downstream and
16 Mbit/s upstream), and on coaxial cable (up to 85 M bit/s down- and upstream); using the
frequency band from 25 kHz to 12 MHz.
VDSL transmits data over short reaches of twisted-pair copper telephone lines with high
speed. It’s been used because of many advantages
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VDSL is significantly faster than other technologies
VDSL is able to support HDTV and VoIP like services due to high bandwidth.
It can also customize it bandwidth according to the usage.
It’s more secure than other’s as provide point to point links and many more.
VDSL uses 7 different frequency bands, by which it can customize the data rate between
upstream and downstream as per the requirement of the services and also under the
regulation of spectrum. There are currently three organizations developing VDSL transceiver
standards; ITU-T, ETSI and ANSI.
Table represents the VDSL speed with different services:-
BROADBAND IN THE HOME
CO 874: Assignment-01
Achal Lekhi (al333@kent.ac.uk)
 Basic Structure of Network
H1
INTERNET
H2
VDSL
ACCSESS POINT (VDSL)
PSTN
VDSL
Equipment
S
P
L
I
T
E
R
H3
VDSL
VDSL
H4
VDSL
VDSL
H5
So on...
Router
H1 Houses
HOW TECHNOLOGY WORKS
Above architecture represents the whole network structure of the buildings, here we have
number of houses in the right hand side which are connected to the VDSL cable link to the
access point where the voice and the data bit’s are separated and from there it leads to the
VDSL equipment and this equipment make calculation and send voice data to PSTN (Public
switched telephone network) and other data to internet.
Initially when the house wants to connect to the internet/PSTN, it create connection with
the access point and separator separates the voice and rest data from that point and the
request will then process to the switch which transfer data to routers and it will reach its
destination. As for the above network, cost of installation is high but not very high as copper
wires are required for the end terminal connections so no major engineering required for
the network, switches, VDSL modem and router are required for the connection to the
internet. Apart from all the above requirements it’s beneficial if we uses the optical fibre
cable for the remote location as to provide high bandwidth and better services to the
network.
CO 874: Assignment-01
Achal Lekhi (al333@kent.ac.uk)
BROADBAND IN THE HOME
TOPOLOGY
As the VDSL is a point to point transmission technique across the reference points, so we
can use star, point to point and mesh topology in the network. For point to point based
network, Point to Point topology is the best for the VDSL implementation. The most
common topology for DSLs is a star network. The purpose of the network is to interconnect
multiple endpoints located at various customer premises with one centrally located
endpoint.
Because of the point to point nature of VDSL, Point to point networks utilizing the benefits
of VDSL. Applications for VDSL point to point networks include the provision of an individual
high speed connection or to multiplex a number of lower speed connections onto a single
high speed VDSL connection. In this scenario we are using with number of houses so it
provides a symmetric service profile for all the users. Due to the individual requirements of
number of users in terms of required bandwidth, distance and transport each VDSL
connection may have a specific profile.
Operating a higher number of point to point VDSL connections within a cable plant may
require a certain level of network engineering. But at the end we got a higher rate of data
transmission and better bandwidth with multiple services. Data rates can be achieved with
the higher rates and with better quality and each user is connected independently so higher
speed and fewer interfaces between the connection and best part is easy to upgrade the
topology with any of the equipments.
BENEFIT’S
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Connection is always on (24x7).
Bandwidth is shared with the maximum speed.
Unlimited Usage.
Each customer gets advance services like VoIP and HDTV etc’s.
Each customer gets their own email address, public IP.
As the above network, it’s complete within itself and its eco friendly as well. The latest
advancement in the VDSL is the VDSL modem i.e. Actiontec Debuts Q1000 Modem Router,
it’s a wireless gateway and dual-core which support many services including media sharing
and online gaming.
It’s very easy to maintain the network and even if some problem persists we can easily
identify as point is needed to be configured and system will be brought in the stable state
again. Technology is stable and very efficient with greater throughput.
CO 874: Assignment-01
Achal Lekhi (al333@kent.ac.uk)
BROADBAND IN THE HOME
REFERENCES
DSL forum, © 2001 Digital Subscriber Line Forum, “Aspects of VDSL Evolution”
Available: https://docs.google.com/viewer?url=http://www.broadbandforum.org/technical/download/TR-)$).pdf&pli=1
(Accessed: 2011, October 12).
“Very-high-bit-rate digital subscriber line”, (August 2011), (wikipedia.org),
Available: http://en.wikipedia.org/wiki/Very-high-bit-rate_digital_subscriber_line
(Accessed: 2011, October 12).
“Difference between ADSL and VDSL”, (differencebetween.net), Available:
http://www.differencebetween.net/technology/difference-between-adsl-and-vdsl/
(Accessed: 2011, October 13).