ravi yadav.ppt
DESCRIPTION
Brief description about indian telecom companyTRANSCRIPT
Mahanagar Telephone Nigam Ltd. (MTNL)
ByRavi yadavElectronics & comm.Roll no - 0929231041
About MTNL
• MTNL was set up on 1st April, 1986 by the Government of India to upgrade the quality of
telecom services, expand the telecom network, introduce new services and to raise revenue
for telecom development needs of India’s key metros’ Delhi, the political capital and
Mumbai, the business capital of India. In the past 17 years, the company has taken rapid
strides to emerge as India’s leading and one of Asia’s largest telecom operating companies.
Besides having a strong financial base, MTNL has achieved a market share of
approximately 13% of the Indian telecommunication network with a customer base of over
4.74 million lines.
The company has also been in the forefront of technology induction by converting 100% of
its telephone exchange network into the state-of-the-art digital mode
. • Transparency makes us different- is the motto of the company.
Definition of Broadband
Internet accessAn ‘always-on' data connection that is able to support interactive services including .According to Broadband policy 2004,has the capability of the minimum download speed of 256 kilo bits per second (kbps) to an individual subscriber from the Point Of Presence (POP) of the service provider. According to New Telecom policy 2011, minimum download speed should be 512 kbps.It provides Internet, IPTV and VoIP simultaneously along with basic telephone service.
Freq. spectrum used in Broadband
4 KHz 26 KHz 138 KHz 1 . 1 MHz
UPSTREAM DOWNSTREAM
ADSL Bandwidth
Splitter- a low pass filter.
xDSL, is a family of technologies that provides digital data transmission over the wires of a local telephone networkDSL (Digital Subscriber Line) exploits the unused analogue bandwidth that is potentially available in the wires that run from the user premises to the local exchangeThe phone system nominally passes audio between 0.3 KHz and 3.4 KHz, which is regarded as the range required for human speech to be clearly intelligible. This is known as voiceband or commercial bandwidthThe local loop connecting the telephone exchange to most subscribers is capable of carrying frequencies well beyond the 3.4 kHz upper limit of POTS.DSL takes advantage of this unused bandwidth of the local loop for carrying data.
XDSL
Advantages of DSL TechnologyDSL is more cost-effective because it eliminates the need for extensive and expensive infrastructure upgrades.
Increased Bandwidth capacity in the existing infrastructure.
The speed is much higher than a regular voice band modem.
Voice and data can be transmitted at the same time.
Very Secure and reliable.
ASYMMETRIC DIGITAL SUBSCRIBER LINE
SplitterSplitter
EXCHANGE
ADSL
LT
ISP
Exchange
Eqpt .
Existing
Copper Lines
ADSL MODEM
Telephone Exchange
Telephone Line
Telephone
MTNL Broadband N/W
Internet Gateway( Broadband)
PC
DSL Modem
VoIP
SOFT SWITCH
Telephone
Analog Telephone Adaptor
HEAD ENDEQUIPMENT
(ENCODERS)
DVD
TV Channel
Set Top Box
TV
IPTV And VOIP (Triple Play Service)
IPTV (Internet Protocol Television) delivers television programming to households via a broadband connection using Internet protocols. It requires a IPTV set-top box, and offers key advantages over existing TV cable and satellite technologies. IPTV is typically bundled with other services like Video on Demand (VOD), voice over IP (VOIP) or digital phone, and Web access, collectively referred to as Triple Play.
IPTV : Brief Definition
DSLAM - INTRODUCTION
Digital Subscriber Line Access Multiplexer (DSLAM) is a network device, located in the telephone exchanges of the service providers, that connects multiple customer Digital Subscriber Lines (DSLs) to a high-speed Internet backbone line using multiplexing techniques.
• In terms of the OSI 7 Layer Model, the DSLAM acts like a massive network switch, since its functionality is purely Layer 2.
• The aggregated signal then loads onto backbone switching equipment, travelling through an access network (AN) — also known as a Network Service Provider (NSP) — at speeds of up to 10 Gbit/s and connecting to the Internet-backbone.
• The DSLAM, functioning as a switch, collects the ADSL modem data (connected to it via twisted or non-twisted pair copper wire) and multiplexes this data via the gigabit link that physically plugs into the DSLAM itself, into the Telco's backbone.
TYPES OF DSLAMS IN MTNLA DSLAM delivers exceptionally high-speed data transmission over existing copper telephone lines. A DSLAM separates the voice-frequency signals from the high-speed data traffic and controls and routes digital subscriber line (xDSL) traffic between the subscriber's end-user equipment (CPE) and Broadband Access Server or BBRAS, but it may not be a direct connection; the BBRAS can be located anywhere.
DSLAMs of following make are installed in MTNL:• ERICSSON (Ethernet DSL Access)• HUAWEI (SMARTAX MA 5600)• ALCATEL (7302 ISAM)
DSLAM PORT NAMINGPORT TYPE PORT
NAMING TYPE OF DSLAM
ERICSSON XYYZTTTT
X: DSLAM TYPEYY: DSLAM NO. (01, 02 ETC)Z: SUBRACK NO.(1, 2, 3, 4)TTTT: PORT NO. (0001 TO 1152)
A– 1152 PORTSB – 576 PORTSC – 288 PORTS
HUAWEI XYYZTTTT
X: DSLAM TYPE (I, J, K)YY: DSLAM NO. (01, 02 ETC)Z: SUBRACK NO. TTTT: PORT NO. (0001 TO 0960)
I – 960 PORTSJ – 480 PORTSK – 240 PORTS
18
LocalExchange
MTNLLine MDF
MTNLExch MDF
MTNL Copper< 5Km
DSLAMExch MDF
DSLAMLine MDF
IPDSLAM
MTNL Fiber Network
2x GigEfiber
Tier 2Switch
MDF
EthernetOr USB
RJ-11
2-wire
2-wire
2-wire
Exchange RSU/MSUCustomer home
Spiltter
DSL Modem
DSL OVERVIEW-DSL CONNECTIVITY
Within the block identified as 'Service provider', there are three important components:DSLAM - DSL Access Multiplexer A Digital Subscriber Line Access Multiplexer (DSLAM) is a network device, usually at a telephone company central office, that receives signals from multiple customer Digital Subscriber Line (DSL) connections and puts the signals on a high-speed backbone line using multiplexing techniques. BBRAS - Broadband Remote Access Server The BBRAS is the piece of equipment that sits between the DSLAM at the telephone exchange and the ISP that connects to the Internet. ISP - Internet Service ProviderThe Broadband Access Servers are connected to an Internet Service Provider or ISP. This is the place where the connection to the Internet is made.
DSLAM (DSL Access Multiplexer)
LOCAL LOOP
OF
D
S
L
A
M
B
R
A
S
I
S
P
INTERNET
Connectivity to Gateways• . All the internet traffic is coming from DSLAM to
T2, the from T2 to T1, from T1 to BBRAS as layer 2 traffic. All the BBRAS's are connected to Two switches (known as Aggregation A and Aggregation B) using fiber cable. And these switches are connected to two gateways routers (4th floor and 9th floor) with six pairs of fibers. That is from Agg-A Three pairs of fibers are going to gateway 1 and Three pairs of fibers are going to gateway 2. Same is the case with Agg - B switch.
RADIUS
• Remote Authentication Dial In User Service• Concept of AAA• Authentication• Authorization• Accounting
How Broadband Service Works?
3 、 Authentication system checks account &password ； BRAS
allocates valid IP
3 、 Authentication system checks account &password ； BRAS
allocates valid IP BBRAS
Radius Server
Lan switch
Core
R
5 、 Billing server start accounting
5 、 Billing server start accounting
2 、 PPPoE session ends
here and session ID is
allocated
2 、 PPPoE session ends
here and session ID is
allocated
1 、 PPPoE is
initiated by
subscriber
1 、 PPPoE is
initiated by
subscriber
4、 Subscriber gets IP and
visit Internet
4、 Subscriber gets IP and
visit Internet
BB Service Flow
PC CPE DSLAM T2 T1 BRAS
Service flow begins from Client BRAS which terminated PPP sessions.The process for user connection to internet is:
1. Client starts pppoe session by using pppoe software.2. ADSL modem translates IP packets into ATM cell.3. DSLAM recovers ATM cells to IP packets.4. DSLAM uses Q-in-Q protocol/VMAC, which adds a new vlan
/vmac tag to the recovered IP packets. Each user has a respective vlan/vmac.
5. T2 forwards IP packet to T1 & T1 transfers the IP packets to BRAS.
6. BRAS also supports Q-in-Q protocol /vmac according to different outer vlan and inner vlan to identify Different users.
T1/T2/Aggregation/NOC SwitchesDefinition: They are LAN switches
used for aggregating and cross-connecting clients, servers and other network devices.
Devices used in MTNL: 3COM 7700 LAN Switches (ERICSSON) and NE80E T-1 Switch, S6506 T-2 Switch (HUAWEI)
Broadband Remote Access Server (BRAS)
Definition: BRAS is a network device used to route traffic to and from broadband remote access devices such as DSLAM on an ISP network. It aggregates users sessions from access network and plays major role policy management and QoS.
Devices used in MTNL: Juniper ERX 1440 (ERICSSON) &
MA5200G-8 (HUAWEI)
Thanks For Your Attention