1. Industrial Training Seminar on BSNL Submitted By:- SHUBHAM
SINGH B.Tech.(EC) Final Year Roll No. 111300208 SESSION :
2014-15
2. INTRODUCTION Bharat Sanchar Nigam Limited is the worlds
seventh largest telecommunication company. Its responsibilities
includes improvement of the quality of already installed telecom
services, expansion of telecom services in rural areas and
acquiring confidence among its customers. It provides a
comprehensive range of services in India, which include wireless
connections, CDMA mobile, GSM lines, Internet, broadband, MPLS-VPN
(multi protocol label switching-virtual private network), VSAT
(very small aperture terminal) WIMAX,FTTHand VOIP (voice over
Internet protocol). Within this short span of time, it has also
become one of the largest public sector companies in India.
3. WORKING OF BASIC TELECOMMUNICATION NETWORK This section
includes brief introduction of how a call is processed when we dial
a call from basic telephone to another basic telephone or from
basic to mobile or vice versa. CALL SETUP: When a subscriber calls
to another subscriber first its request goes to the nearest
switching centre that is PSTN (Public Switching Telecommunication
Network). Then it processes the caller and subscribers number if it
exists in the same BSC (Base Station Controller) then call setup is
completed. If subscriber is not in the same BSC then call transfer
to MSC (Mobile Switching Centre) then it transfers the call to
prior BSC then call setup is completed. If Caller calls to a mobile
subscriber then call transfer is done by MTSO(Mobile Telephone
Switching Office) now call transfer is done on BTS (Base
Transceiver Station) and call setup is completed.
4. Parts of a Telecommunication network The main parts of a
Telecommunication network are: 1.Telephone Exchange 2.Main
Distribution Frame (MDF) 3.Switch Room
5. TELEPHONE EXCHANGE Equipment which effects interconnection
of telephones is known as switching equipment. The switching
centre, which houses the terminating and switching equipment is
called telephone exchange. A telephone exchange is a
telecommunication system used in the public switched telephone
network or in large enterprises. An exchange consists of electronic
components that interconnect (switch) telephone subscriber lines or
virtual circuits of digital systems to establish telephone calls
between subscribers
6. About the exchange All telephone subscribers are served by
automatic exchanges. Todays automatic exchanges use a pair of
computers. One running the program that provides services. Second,
monitoring the operation of the first, ready to take over in a few
seconds in the event of equipment failure. Various exchanges
present in BSNL are: 1. C-DOT 2. OCB(ORGANE DE COMMANDE B2 VERSION)
3. EWSD
7. C-DOT It work on telecom technology, products and services.
Provide solutions for current and future requirements of
telecommunication and converged networks including those required
for rural application. Provide market orientation to R & D
activities and sustain C-DOT as center of excellence. OCB(ORGANE DE
COMMANDE B2 VERSION) It is a digital switching system. The system
supports all the existing signaling system. The system has auto
recovery feature. When a serious fault occur in control unit, it
gives a message to SMM (operation & maintenance unit).
8. OCB(ORGANE DE COMMANDE B2 VERSION)
9. EWSD The EWSD Digital Switching Systems offer a wide range
of telephony features and supplementary services. Further
capabilities can be developed to meet specific customer needs.
10. MAIN DISTRIBUTION FRAME(MDF) M.D.F. is a media between
switching network and subscribers line. It is a termination point
within the local telephone exchange where exchange equipment and
terminations of local loops are connected by jumper wires.
FUNCTIONS OF MDF: All cable copper wires supplying services through
user telephone lines are terminated and distributed through MDF.
The most common kind of large MDF is a long steel rack accessible
from both sides. Each jumper is a twisted wire. It consists of
local connection and broadband connection frames for the main
Exchange area. The MDF usually holds central office protective
devices including heat coils and functions as a test point between
a line and the office. It provides testing of calls. It checks
whether fault is indoor or external. All lines terminate
individually
11. Structure Of MDF
12. ORGANIZATION OF MDF Vertical side Horizontal side Vertical
side Rack:- On the rack, the tags are situated. One rack is having
eight tags. The counting is done from up (0) to down (7). Tags:-
Each rack consists of eight tags 1 tag = 4 core 1 core = 4 bunch 1
bunch = 2 line N.E:-The word NE stands for the NUMBER OF EQUIPMENT.
It is used for testing number. Wedge:- Wedge is used as a device
for checking the ring. Wedge is placed in jack strips, which is
connected to telephone for checking.
13. Horizontal side The horizontal side connected to the
underground cable. This cable is having 100 pairs. These pair are
distributed when company allot the telephone number to the
subscriber. Horizontal side is again subdivided in two parts: One
part is connected with the vertical side. Another with the
subscriber line by using 100 pair underground cable.
14. POWER PLANT As we know that, the power is the main source
or any organization. It is the case of E-10B exchange. That is the
first requirement of any organization is the input. The main source
of this exchange is AC supply. The main part of power room are:- 1.
Batteries for providing 48V supply 2. UPS (Uninterruptable Power
Supply) 3. Charging - Discharging Unit 4. Inverter and Converter
Unit
15. Switch Room Switch room consists of BM(Benjamin Moore) and
CM cabinets mounted in standard switch. These cabinets are fastened
to a switch Room and interconnected by cables
16. VARIOUS INTERNET SERVICES LEASED LINES The information sent
through the leased line travels along dedicated secure channels,
eliminating the congestion that occurs in shared networks. between
two points set up by a telecommunications carrier. They can be used
for telephone, data, or Internet services A leased line (dedicated
line) is a permanent Optical Fibre Cable(OFC) or telephone
connection. It is commonly used in ATMs. WI-FI (WIRELESS FIDELITY)
A Wi-Fi network provides the features and benefits of traditional
LAN technologies such as Ethernet and Token Ring without the
limitations of wires or cables. WIFI is a wireless LAN Technology
to deliver wireless broad band speeds up to 54 Mbps to Laptops, PCs
Wi-Fi enabled phones etc.
17. GENERAL PACKET RADIO SERVICE (GPRS) General packet radio
service (GPRS) is a packet oriented mobile data service available
to users of the 2G cellular communication systems, global system
for mobile communications (GSM), as well as in the 3G systems. In
2G systems, GPRS provides data rates of 56-114 kbps GPRS extends
the GSM circuit switched data capabilities and makes the following
services possible: 1. Always on Internet access. 2.Multimedia
messaging service (MMS). 3.Push to talk over cellular (PoC/PTT).
4.Point to Point (P2P) service: inter-networking with the internet
(IP). 5.Increase message sending speed 30 messages per minute
approximately.
18. BSNL Broadband Service Broadband refers to a connection
that has capacity to transmit large amount of data at high speed.
Presently a connection having download speeds of 256 kbps or more
is classified as broadband. When connected to the Internet
broadband connection allows surfing or downloading much faster than
a dial-up or any other narrowband connections. BSNL offers 2 Mbps
minimum download speed for its Broadband connections. Requirement
for providing Broad Band connection 1.Personal Computer 2.ADSL
Modem 3.Land Line Connection 4.Splitter for separating telephone
from Personal computer 5.High speed Internet Access: This is the
always-on Internet access service with speed ranging from 256 kbps
to 8 Mbps.
19. WIMAX WI-MAX is an acronym that stands for World-wide
Interoperability for Microwave Access and this technology is
designed to accommodate both fixed and mobile broadband
applications. SALIENT FEATURES OF WIMAX ARE: 1.OFDM-based physical
layer. 2.Very high peak data rates. 3.Adaptive modulation and
coding (AMC) 4.Support for TDD and FDD OFDMA. 5.Flexible and
dynamic per user resource allocation. 6.Support for mobility.
7.IP-based architecture. FTTH FTTH is an acronym which stands for
Fiber To The Home.In this technology an optical fiber of high
bandwidth and frequency is connected to the local residence of the
user to provide high speed internet facility upto higher mbps to
gbps.This facility is first launched by BSNL in India.
20. OSI NETWORKING MODEL The open systems interconnection model
defines all the methods and protocols needed to connect one
computer to any other over a network.It consists of following seven
layers: Physical Layer:The physical layer defines the properties of
the physical medium used to make a network connection Data Link
Layer: the data link layer, layer 2, defines standard that assign
meaning to the bits carried by the physical layer Network Layer:
The network layer, Layer-3, is where a lot of action goes on for
most networks. Transport Layer: The Transport Layer, layer-4,
manages the flow of information from one network node to another.
Session layer: The session layer, layer-5, defines the connection
from a user to a network server, or from a peer on a network to
another peer Presentation Layer: The presentation layer, layer-6,
takes the data supplied by the lower level layer and transform so
it can be presented to the system Application Layer: The
Application layer, layer 7, controls how the operating system and
its application interact with network.
21. IPv4 Addressing This section covers some of the basic
concepts of IPv4 addressing, such as how the Internet's address
architecture uses the binary and dotted-decimal versions of IPv4
addressing. This section also reviews the structure of IPv4
addresses, such as the various classes of IPv4 . 32-bit IP
addresses are written using dotted-decimal notation. Each 32-bit
address is divided into four groups of eight, called octets. Each
octet is converted to decimal and then separated by decimal points,
or dots.Bit IP addresses are written using dotted-decimal notation.
A 32-bit IP address is a binary number:
10101100000111101000000000010001 This binary number can be divided
into four octets: 10101100 00011110 10000000 00010001 Each octet
(or byte) can be converted to decimal: 172 30 128 17 Finally, the
address can be written in dotted-decimal notation:
172.30.128.17
22. Various classes of IPV4 address
23. FIBER OPTICS TRANSMISSION SYSTEM FIBER OPTICS: The use and
demand for optical fiber has grown tremendously and optical-fiber
applications are numerous. Telecommunication applications are
widespread, ranging from global networks to desktop computers.
These involve the transmission of voice, data, or video over
distances of less than a meter to hundreds of kilometers, using one
of a few standard fiber designs in one of several cable designs.
ADVANTAGES OF FIBRE OPTICS : Fiber Optics has the following
advantages : SPEED: Fiber optic networks operate at high speeds -
up into the gigabits BANDWIDTH: large carrying capacity DISTANCE:
Signals can be transmitted further without needing to be
"refreshed" or strengthened. RESISTANCE: Greater resistance to
electromagnetic noise such as radios, motors or other nearby
cables. MAINTENANCE: Fiber optic cables costs much less to
maintain.
24. OPTICAL FIBER CABLE(OFC) Optical Fiber is new medium, in
which information (voice, Data or Video) is transmitted on the
principle of Total Internal Reflection through a glass or plastic
fiber, in the form of light. In the following sequence.
1.Information is encoded into Electrical Signals. 2.Electrical
Signals are converted into light Signals. 3.Light Travels down the
Fiber. 4.A Detector Changes the Light Signals into Electrical
Signals. 5.Electrical Signals are decoded into Information.
25. In wireless communication every region is divided into
cells. Cell size is constant for whole system. GSM is a form of
multiplexing, which divides the available bandwidth among the
different channels. Most of the times the multiplexing used is
either TDM (Time division multiplexing) or FDM (Frequency Division
Multiplexing). SM differs from its predecessor technologies in that
both signaling and speech channels are digital, and thus GSM is
considered a second generation (2G) mobile phone system.
26. 2G GSM networks operate in the 900 MHz or 1800 MHz bands
GSM-900 uses 890915 MHz to send information from the mobile station
to the base station (uplink) 935960 MHz for the other direction
(downlink), providing 125 RF channels (channel numbers 0 to 124)
spaced at 200 kHz. Duplex spacing of 45 MHz is used.
27. CODE DIVISION MULTIPLE ACCESS (CDMA) Code Division Multiple
Access (CDMA) consistently provides better capacity for voice and
data communications that other commercial mobile technologies,
allowing more subscribers to connect at any given time, and it is
the common platform on which 3G technologies are built. CDMA is a
spread spectrum technology, allowing many users to occupy the same
time and frequency allocations in a given band/space ADVANTAGES OF
CDMA: Increased cellular communications security Simultaneous
conversations Low power requirements and little cell-to-cell
coordination needed by operators. Extended reach-beneficial to
rural users situated far from cells.
28. MS refers to the physical phone itself uniquely identified
by the International Mobile Equipment Identity (IMEI) number.
SIM(Subsciber Identification Module) is small smart card that is
inserted into the phone and carries information specific to the
subscriber identified by International Mobile Subscriber Identity
(IMSI) number.
29. It carry out radio communications between the network and
the MS. It has handles speech encoding, encryption, multiplexing
(TDMA), and responsible for modulation and demodulation. Installed
between 1 and 16 Transceivers (TRX)
30. It is responsible for allocation of radio channels.
Operates frequency administration power and signal measurements
from the Mobile station. handovers from one BTS to another.
31. It is responsible for call routing, call setup, and basic
switching functions. Different BSCs are connected to the MSC.
Inner-BSC handoffs as well as coordinates with other MSC's for
inter- MSC handoffs.
32. DATABASES HLR(Home Location Register ) maintains subscriber
specific information such as the MS,ISDN(Integrated Services
Digital Network), IMSI, current location of the MS, roaming
restrictions. VLR(Visitor Location Register ) is a database that
contains a subset of the information located on the HLR.
33. REFERENCES 1. Data Communication And Networking- Behrouz A.
Foruzan 2. Wireless Communication and Networks-William Stallings 3.
Computer Networking Kurose & Ross 4. www.bsnl.co.in 5.
www.newbsnl.co.in