A.D.S.L. presentation
-
Upload
rama-kaushik -
Category
Education
-
view
2.275 -
download
1
description
Transcript of A.D.S.L. presentation
1
WELCOME TO THE RISING TECHNOLOGY
“ASYMMETRIC DIGITAL SUBSCRIBER LINE”
2
INDEX
CHAPTER 1
INTRODUCTION
1.1 DIFFERENT VARIANTS OF DSL 1.2 WHAT IS ADSL 1.3 WHAT ARE THE BENEFITS
CHAPTER 2
FUTURE OF ADSL
3
CHAPTER 3
A.D.S.L. CAPABILITIES
3.1 FREQUENCY RESPONSE
CHAPTER 4
ADSL TECHNOLOGY
CHAPTER 5
METHODS TO SPLIT THE SIGNAL
5.1 CARRIER LESS AMPLITUDE5.2 DISCRETE MULTITONE
5.3 PASSIVE FILTERS
4
INDEX…
CHAPTER 6
ADSL EQUIPMENT
CHAPTER 7
DISTANCE LIMITATIONS
6.1 DSL EQUIPMENT DSLAM
5
CHAPTER 8
INSTALLATION ISSUES
CHAPTER 9
APPLICATIONS
6
CONCLUSION
&
REFERENCES
7
CHAPTER #01
INTRODUCTIONPAST DECADE HAS SEEN EXTENSIVE GROWTH IN THE TELECOMMUNOCATION INDUSTRY
POPULARITY OF INTERNET & OTHER DATA COMMUNICATION SERVICES HAS INCREASED
MAJORITY OF INTERNET USERS ACCESS THEIR SERVICE VIA MODEMS CONNECTED TO P.O.T.S.
P.O.T.S. WAS DESIGNED FOR VOICE TRANSMISSION AT FREQUENCIES BELOW 3 KHz
8
TO INCREASE PERFORMANCE OF NEW ONLINE SERVICES, THE BANDWIDTH HUNGRY PUBLIC MUST CONSIDER OTHER OPTIONS
TECHNOLOGIES, SUCH AS I.S.D.N. OR CABLE CONNECTIONS, REQUIRE SPECIAL CABLING
A P.O.T.S. CONNECTION PROVIDED AN ADEQUATE MEDIUM FOR RELATIVELY SMALL AMOUNTS OF DATA THAT REQUIRED TO BE TRANSMITTED
SO THE EXISTING SYSTEM WAS THE LOGICAL CHOICE OVER SPECIAL CABLING
9
1.1 DIFFERENT VARIANTS OF DSLH.D.S.L. IT IS THE PIONEERING HIGH SPEED FORMAT, BUT NOT COMMERCIALLY VIABLE OPTION DUE TO ITS NEED FOR 2 TWISTED PAIRS & DOESN’T HAVE SUPPORT FOR NORMAL TELE PHONE SERVICES
S.D.S.L. IT IS SYMMETRIC DSL OPERATES OVER A SINGLE TWISTED PAIR LIMITED TO SHORT DISTANCES SUFFERS N.E.X.T.
I.S.D.L. STANDS FOR I.S.D.N. DSL
10
SIMILAR TO I.S.D.N. TECHNOLOGY LACKS SUPPORT FOR ANALOG VOICE
V.D.S.L.VERY HIGH BIT RATE D.S.L.
REQUIRES SHORTER CONNECTIONS THAN ARE GENERALLY PRACTICAL
A.D.S.L.MOST PROMISING TECHNOLOGY
SUITABLE FOR PERSONAL BROADBAND REQUREMENTS
ALLOWS SAME CHANNEL TO STILL ACT AS A TRADITIONAL SERVICE
11
1.2 WHAT IS A.D.S.L.A MODEM TECHNOLOGY
CONVERTS EXISTING TWISTED PAIR TELEPHONE LINES INTO ACCESS PATHS FOR MULTIMEDIA & HIGH SPEED DATA COMMUNICATIONS
CAN TRANSMIT UPTO 6Mbps TO SUBSCRIBER
832 Kbps IN BOTH DIRECTIONS
EXPANDS ACCESS CAPACITY BY A FACTOR OF 50 OR MORE
IT ALLOWS MORE BANDWIDTH DOWNSTREAM THAN FOR UPSTREAM
12
USERS OF THESE APPLICATIONS DOWNLOAD MORE
INFORMATION THAN THEY SEND
A GATEWAY IS COMMONLY USED TO MAKE AN ADSL CONNECTION
IT IS WIRELESS
13
1.3 BENEFITS OF A.D.S.L.PROVIDES HIGH SPEED INTERNET ACCESS USING REGULAR TELEPHONE LINES
CONNECTIVITY-ALWAYS ON
DATA SECURITY
EASE OF USE
NO DIAL-UP IS REQUIRED
SPEED IS UPTO 25 TIMES FASTER THAN ANALOG MODEMS
CHAPTER #02FUTURE OF A.D.S.L.
ADSL will play a crucial role over the next decade or more as telephone companies enter new
markets for delivering information in video and multimedia formats. New broadband cabling will
take decades to reach all prospective subscribers. Success of these new services will depend on
reaching as many subscribers as possible during the first few years. By bringing movies, television,
video catalogs, remote CD-ROMs, corporate LANs, and the Internet into homes and small
businesses, ADSL will make these markets viable and profitable for telephone companies and
application suppliers alike.ADSL Capabilities
15
16
CHAPTER #03ADSL CAPABILITIES
oADSL MODEM CONNECTED TO EACH END OF TWISTED PAIR TELEPHONE LINE
o3 INFORMATION CHANNELS ARE CREATED :-
o1). HIGH SPEED DOWNSTREAM CHANNELo2). A MEDIUM SPEED DUPLEX CHANNELo3). A BASIC TELEPHONE SERVICE CHANNEL
oADSL GUARANTEES UNINTERRUPTED TELEPHONE SERVICE EVEN IF ADSL FAILS
oDOWMSTREAM RATES DEPEND ON :-
o1). LENGTH OF COPPER LINE
2). ITS WIRE GAUGE
3). PRESENCE OF BRIDGED GAPS
4). CROSS COUPLED INTERFERENCE
LINE ATTENUATION INCREASES WITH LINE LENGTH & FREQUENCY
LINE ATTENUATION DECREASES WITH INCREASE IN WIRE DIAMETER
18 POTS & A.D.S.L. DATA
19
CHAPTER #04ADSL TECHNOLOGY
DEPENDS UPON ADVANCED DIGITAL SIGNAL PROCESSING TECHNOLOGY & ALGORITHMS
OUTSIDE - ADSL LOOKS SIMPLE
INSIDE- MIRACLE OF MODERN TECHNOLOGY
IT CONSISTS OF :- TRANSMITTER & RECEIVER…..
1).TELEPHONE EXCHANGE
2). SPLITTER
3). DSLAM , ISP
20
4).SPLITTER
5). ADSL MODEM
6). COMPUTER
7). PHONE, FAX
FDM-ONE BAND TO UPSTREAM OTHER TO DOWNSTREAM
DOWNSTREAM-:TDM; HIGH & LOWCHANNELS
UPSTREAM-:CORRESPONDING LOW CHANNELS
OVERLAPPING REMOVED BY ECHO CANCELLATION
BLOCK DIAGRAM
21
CHAPTER #05METHODS TO SPLIT THE SIGNAL
1). CARRIERLESS AMPLITUDE / PHASE (CAP)
TELEPHONE SIGNAL DIVIDED IN 3 PARTS
i. VOICE CONVERSATIONS- 0 TO 4 KHz (POTS CKT)
ii. UPSTREAM CHANNEL-25 TO 160 KHz (FROM USER BACK TO SERVER)
iii. DOWNSTREAM CHANNEL- BEGINS AT 240 KHz (FROM SERVER TO USER)
INTERFERENCE MINIMISED
24
2). DISCRETE MULTITONE
DIVIDES SIGNAL INTO 247 SEPARATE CHANNELS,EACH 4KHz WIDE
EQUIVALENT TO GETTING 247 MODEMS
SIGNALS SHIFTED B/W DIFFERENT CHANNELS
MORE COMPLEX THAN C.A.P.
MORE FLEXIBLE
25
3). LOW PASS FILTERS
BLOCK SIGNALS ABOVE CERTAIN FREQUENCY
ALL CONVERSATIONS- BELOW 4 KHz
LPF’s DESIGNED TO BLOCK SIGNALS ABOVE 4KHz
PREVENT DATA SIGNALS FROM INTERFERING WITH STANDARD TELEPHONE CALLS
ADSL EQUIPMENTSIt uses two pc’s of equipments one at the customer end and one at the internet services provider At the customer location there is DSL transceiver also called as “DSL MODEM” and ATU-R too.
DSL service provider has a DSL access multiplexer(DSLAM ) to receive customer connection.
The transceiver can connect to the customer equipment by using USB or 10 base –T Ethernet connections.
The devices used by businesses may combine network routers network switches or other networking equipments
DSL EQUIPMENT:DSLAM It really allows DSL to happen
It takes connection from many customers and aggregates them on to a single high capacity connection to the internet It is flexible and able to support multiple types of DSL in a single central office.
DSLAM
LIMITATIONS IT IS A DISTANCE SENSITIVE TECHNOLOGY.
LIMIT FOR ADSL service is 18000 feet.
Maximum downstream speed is 8 mbps at a distance of about 6000 feet.
Maximum upstream speed is 640 kbps.
ADSL cant be received using bridge tapes , fiber optic cables and loading coils. .
INSTALLATION ISSUES
DSL ADSL It do not uses the
frequency spectrum Splitter or micro filter
are used near demarcation point
This requires a technician for installation purposes
More costlier DSL signal is
separated at demarcation point
It uses the frequency spectrum
Frequency filters are used at the customers premises to avoid interference
This do not require technician
Less costlier than DSL DSL signal is filtered at each
phone outlet by use of LPF for voice and HPF for data
ADSL RANGE Maximum range for DSL without a repeater is 5.5 km
As distance decreases towards the telephone company office , the data rate increases
For larger distances , DSL service is provided only when phone company has extended the local loop with optical fiber cable
ADSL SPEED FACTORS The distance from local exchange
The type and thickness of wires used
The number and type of joins in the wire
The proximity of the wire to other wires carrying ADSL ,ISDN and other non voice signals
The proximity of the wires to radio transmitters
ADSL REQUIREMENTS
Phone line , activation by your phone company for it
Filter to separate the phone signal from the internet signal
ADSL modem Subscription with an ISP supporting ADSL
APPLICATION1.HIGH SPEED INTERNET ACCESS
2. E-COMMERCE
3.DISTANCE LEARNING
4.VIDEO CONFERENCING
5.ENTERTAINTMENT-ONLINE GAMING
CONCLUSION
IT IS ASYMMRTRIC.
ALLOWS MORE BANDWIDTH FOR DOWNSTREAM THAN UPSREAM DATA FLOW.
ADSL modems create multiple channels using FDM or echo cancellation.
It is ideal for those who download much more data than they send.
QUERIES ????