This document provides an overview of broadband and DSL technology. It discusses how broadband provides high-speed internet access from 256 kbps to several mbps. It then describes ADSL technology, how it works by splitting bandwidth on copper telephone lines into channels for upstream, downstream, and voice. The document outlines the various components used in broadband networks like DSLAMs, BRAS, CPE, and discusses how they connect and function. It also lists some services that can be accessed through broadband like video and audio on demand. In closing, it mentions how broadband can help bridge the digital divide and strengthen education through improved internet access.

1. PRESENTED BY:
RAMAKANT TYAGI

2. Introduction
Advantages
ADSL technology
Types of DSL modulation
Various components and their arrangement
Cable Modem
ECHO Cancellation
Services through broadband
CONTENTS

3.  BSNL is fourth largest Telecommunication Company in Asia
and seventh in world today.
 It is the largest provider of fixed telephony and fourth
largest mobile telephony provider in India, and is also a
provider of broadband services.
 At present BSNL enjoys around 60% of market share of ISP
services.
 2007 was declared as "Year of Broadband" in India.

4. .Broadband refers to high internet access.
.It provides services more than 256 kbps to several mbps.
.There are many different technologies both wired and
wireless(WIMAX).
.BSNL’ s broadband working under the brand name “cell
one” and MTNL ’s brand name under “tri band”.
INTRODUCTION

5. • Always on
• Fast speed ranging from 256kbps to 2mbps
• No disconnection
• No additional charge access
• Telephone and data simultaneously

6. • ASYMMERTIC-indicates downstream and upstream
capacity is not same
• DIGITAL-means BINARY “0” AND “1”
• SUBSCRIBER LINE-means both data and voice are send
over twisted copper cable to the subscriber

7. FEATURES OF ADSL
TECHNOLOGY
 Distance sensitive technology
 Internet connection is always on
 Simultaneous use of phone lines for voice as well as
data.
 It is highly reliable and secure.
 High speed in mbps.

8. VARIOUS XDSL
TECHNOLOGIES
 ADSL(Asymmetric digital subscriber line)
 VDSL(Very high speed digital subscriber line)
 RADSL(Rate adaptive digital subscriber line)
 HDSL(High data rate digital subscriber line)
 SDSL(symmetric digital subscriber line)

9. WORKING OF ADSLADSL works by splitting the available bandwidth on
twisted copper wire(telephone lines)into three different
channel:
 A high speed download stream channel
 A medium speed upstream channel
 POTS-Plain Old Telephone service channel
25.875khz to 138 kHz → upstream communication
138 kHz to 1104 kHz → downstream communication
0-4 kHz → PSTN

11. • CAP(Carrier less amplitude phase modulation)
• DMT(Discrete multi tone)modulation
CAP is now an old technique, now a days we prefer
DMT
• DMT (DISCRETE MULTI TONE MODULATION)
Bandwidth ranging from 26 kHz -1.1 MHz is splitted
into two bands using FDM(frequency division
multiplexing) and echo cancellation technique

12. 1.Upsteam band(26khz-138khz)
2.Downsteam band(138khz-1.1mhz)
Now using FFT(fast Fourier transform) we divide them
further in to 256 discrete sub channels each of band
width 4khz.

13. It is used so that downstream channel overlaps
upstream channel so that upstream channel and
downstream channel are sent simultaneously over
same telephone wire.

15. • DSLAM(Digital Subscriber Line Access multiplexer)
• BRAS(Broadband Remote Access Server)
• SSSS(Subscriber Service Selection System)
• LAN switch
• CPE(customer premises Exchange)

16. • DSL CPE: At customer premises. On one end it
connects telephone cable coming from exchange via
splitter. At the other end, it connects to PC through
Ethernet / USB Port.
• DSLAM: called as DSL Access Multiplexer. It has a built
in splitter which splits voice and data. It is a technique
to send both voice and data over same twisted
telephone wire.
• LAN SWITCH: For aggregating multiple DSLAM and
providing a common uplink to the core.

17. • BRAS: called as Broadband Remote Access Server. First
intelligent device in the whole chain. It terminates the
customer session, authenticates, allot IP addresses
and keeps track of user session for billing .
• SSSS: Called as Subscriber Service Selection System.
When customer logs in he will be welcomed with this
customized screen from where he can select various
range of service.

19. High speed internet access.
Bandwidth on demand.
Multicasting
Dial vpn service
Audio on demand
Video on demand
Billing and IPTV

21. Broadband helps in bridging the digital division between
rural and urban regions and hence uniting the world.
“One key to strengthen education , innovation in
communities is to harness the full power of internet and
that means faster and more widely available broadband” as
mentioned by Mr. Obama (The U.S President)
‘High speed internet connection is the need of the hour and
Broadband is a solution to it!’

22. THANK YOU