ADSLADSL

Yanmei Tong (103801)Yanmei Tong (103801)

Asymmetric Digital Subscriber Asymmetric Digital Subscriber LineLine

Frequently Asked Frequently Asked Questions About ADSLQuestions About ADSL

What is it?What is it? What are the benefits?What are the benefits? How fast is it?How fast is it? How does it work?How does it work? What can I use it for?What can I use it for? Where is the technology headed?Where is the technology headed? How do I get ADSL?How do I get ADSL?

What Is ADSL?What Is ADSL?

ADSL is a type of DSL which is best ADSL is a type of DSL which is best suited for residential use.suited for residential use.

ADSL is a new broadband ADSL is a new broadband communication technology that communication technology that creates high-speed access to the creates high-speed access to the Internet and remote networks using Internet and remote networks using the phone lines that are already the phone lines that are already present in your home. ADSL is present in your home. ADSL is superior to analog modems in many superior to analog modems in many respects.respects.

What Are the Benefits of What Are the Benefits of ADSL?ADSL?

You can talk on the phone and use You can talk on the phone and use the Internet at the same timethe Internet at the same time

You can connect to the Internet at You can connect to the Internet at up to 140 times faster than analog up to 140 times faster than analog modemsmodems

Your connection to the Internet is Your connection to the Internet is always onalways on

What Are the Benefits of What Are the Benefits of ADSL?ADSL?

Your home has its own dedicated Your home has its own dedicated connectionconnection

Your connection is highly reliable Your connection is highly reliable and secureand secure

What Can I Use ADSL for?What Can I Use ADSL for?

Faster downloads of anything Faster downloads of anything digitaldigital

CD-quality audioCD-quality audio Graphics-rich web sitesGraphics-rich web sites Faster and better multimediaFaster and better multimedia High-speed multiplayer gamesHigh-speed multiplayer games

Lightning Fast InternetLightning Fast Internet

ADSL offers different speedsADSL offers different speeds– Full-rate ADSL has the potential to Full-rate ADSL has the potential to

deliver data at speeds up to 8 deliver data at speeds up to 8 megabits per second.megabits per second.

– Service providers can also offer Service providers can also offer slower rates (from 256 kilobits per slower rates (from 256 kilobits per second) at lower costs.second) at lower costs.

Always-on, Simultaneous Always-on, Simultaneous ConnectionConnection

Because the data signals are Because the data signals are transmitted separately from voice transmitted separately from voice signals, your Internet connection signals, your Internet connection stays on all the timestays on all the time– No more logging on and off No more logging on and off – Connect to the Internet without having Connect to the Internet without having

disable call waitingdisable call waiting– No more waiting-just open your No more waiting-just open your

browser and go!browser and go!

Dedicated ConnectionDedicated Connection

Unlike a cable modem, ADSL gives Unlike a cable modem, ADSL gives you a dedicated line to the you a dedicated line to the Internet. With cable modems, you Internet. With cable modems, you are using a shared line with all the are using a shared line with all the others users in your neighborhood.others users in your neighborhood.

ADSL ReliabilityADSL Reliability

One strength of phone providers is their One strength of phone providers is their small number of service outages per small number of service outages per year, something cable company cannot year, something cable company cannot claim.claim.

Even if the power goes out, you will still Even if the power goes out, you will still be able to make phone calls.be able to make phone calls.

Unlike cable modems, your connection Unlike cable modems, your connection speed will not be affected by how much speed will not be affected by how much bandwidth your neighbors use.bandwidth your neighbors use.

ADSL SecurityADSL Security

The dedicated connection that The dedicated connection that ADSL uses provides more security ADSL uses provides more security than cable.than cable.

Cable modem users share Cable modem users share bandwidth with their neighbors. bandwidth with their neighbors. Information traveling across the Information traveling across the network is easier to snoop.network is easier to snoop.

How Does ADSL Work?How Does ADSL Work?

One phone line delivers voice and One phone line delivers voice and a high-speed Internet connectiona high-speed Internet connection

Voice/fax calls only use the Voice/fax calls only use the frequencies below 4 khzfrequencies below 4 khz

Frequencies above 4 khz are Frequencies above 4 khz are reserved for data transmissionreserved for data transmission

ADSL HistoryADSL History

1995-Bell Labs discovers a new 1995-Bell Labs discovers a new way to make traditional copper way to make traditional copper wires support new digital services.wires support new digital services.

1990-phone companies start 1990-phone companies start deploying high-speed DSL (HDSL) deploying high-speed DSL (HDSL) to offer T1 service on copper lines to offer T1 service on copper lines without the expense of installing without the expense of installing repeaters.repeaters.

ADSL HistoryADSL History

Phone companies begin to Phone companies begin to promote ADSL as a way to enter promote ADSL as a way to enter the video marketthe video market

1995-innovative companies begin 1995-innovative companies begin to see ADSL as a way to meet the to see ADSL as a way to meet the need for faster internet access.need for faster internet access.

Now-ADSL is being deployed for Now-ADSL is being deployed for faster internet access across the faster internet access across the united states.united states.

Different Types of ADSLDifferent Types of ADSL

Full rate ADSL (G.Dmt)Full rate ADSL (G.Dmt) Universal ADSL (G.Lite)Universal ADSL (G.Lite)

Full-rate ADSLFull-rate ADSL

Full-rate ADSL boasts data rates Full-rate ADSL boasts data rates ranging from 1.5 to 8 megabits per ranging from 1.5 to 8 megabits per second “downstream” from the second “downstream” from the internet to your computer.internet to your computer.

““Upstream” data rates from your Upstream” data rates from your computer to the internet are as computer to the internet are as high as 1 megabit per secondhigh as 1 megabit per second

Full-rate ADSLFull-rate ADSL

Potential data rates decrease with Potential data rates decrease with increased distance from the phone increased distance from the phone company CO (central office)company CO (central office)

G. Lite ADSLG. Lite ADSL

G.Lite ADSL is a scaled-down G.Lite ADSL is a scaled-down version that delivers up to 1.5 version that delivers up to 1.5 mbps downstream and 384 kbps mbps downstream and 384 kbps upstreamupstream

Less expensive than full-rate ADSLLess expensive than full-rate ADSL G.Lite performance is G.Lite performance is

unacceptable for voice and unacceptable for voice and entertainment applicationsentertainment applications

Splittered Vs. SplitterlessSplittered Vs. Splitterless Conventional phone wiring can transmit Conventional phone wiring can transmit

– Voice signals (phone service)Voice signals (phone service)– Data signals (DSL service)Data signals (DSL service)

Some DSL providers separate the wiring Some DSL providers separate the wiring used for voice from dataused for voice from data

A splitter is used to achieve this and A splitter is used to achieve this and influences how you should influences how you should – Build your home networkBuild your home network– Select your DSL modem or residential Select your DSL modem or residential

gatewaygateway

ADSL FutureADSL Future

Broadscale, nationwide ADSL Broadscale, nationwide ADSL rollouts are happening todayrollouts are happening today

““Given a choice... Those most Given a choice... Those most willing to pay for the service willing to pay for the service choose the telephone company 4 choose the telephone company 4 1/2 times more differently than 1/2 times more differently than cable.” Survey. The yankee group. cable.” Survey. The yankee group. November 1998November 1998

ADSL FutureADSL Future

ADSL service “ in the end will be ADSL service “ in the end will be nearly ubiquitous”-peter mcgrath, nearly ubiquitous”-peter mcgrath, newsweek. November 23, 1998newsweek. November 23, 1998

ADSL SummaryADSL Summary

ADSL provides a new way to use ADSL provides a new way to use existing phone lines.existing phone lines.

It’s faster!It’s faster! It’s always on!It’s always on! Voice and data on one line at the Voice and data on one line at the

same time!same time! ADSL is the best way to get online!ADSL is the best way to get online!