8/22/2019 bsnlppt
1/28
SUMMER TRAINING REPORTHELD AT
BSNL
8/22/2019 bsnlppt
2/28
INDEX
1. COMPANY PROFILE
2. INTRODUCTION
3. ABOUT THE EXCHANGE
4. MDF
>TYPES OF FAULTS
>PROTECTIVE DEVICES
5. OCB
6. GSM
7. MEDIA
8. PROCEDURE FOR HANDLING COMPLAINTS
8/22/2019 bsnlppt
3/28
INTRODUCTION
Today, BSNL is the No. 1 telecommunication company and thelargest public sector undertaking of India and its responsibilitiesincludes improvement of the already impeccable quality oftelecom services, expansion of telecom services in all villages andinstilling confidence among its customers.
EXCHANGE:
Equipment which effects interconnected of telephones is knownas switching equipment.
The switching centre, which houses the terminating and switchingequipment is called telephone exchange.
8/22/2019 bsnlppt
4/28
EXCHANGE LAYOUT
Typical exchange consist of :
Switch Room
Operations and Maintenance (OMC) RoomInput Output processor (IOP) Room
Power Plant Room
Battery Room
Main Distribution Frame (MDF) Room
8/22/2019 bsnlppt
5/28
ABOUT THE EXCHANGE
1. All telephone subscribers are served by automaticexchanges.
2. Todays automatic exchanges uses a pair of computers.
One, running the program that provides services.
Second, monitoring the operation of the first, ready totake over in a few seconds in the event of equipmentfailure.
Various exchanges present in BSNL are:
> C-DOT> OCB> EWSD
8/22/2019 bsnlppt
6/28
MAIN SECTIONS OF EXCHANGE:
There are three components of exchange:
MDF
Power plant
Switching Room.
8/22/2019 bsnlppt
7/28
MAIN DISTRIBUTION FRAME (M.D.F) :
INTRODUCTION:
- MDF means Main Distribution Frame. Local cablecontact at MDF .
- All types of cables out to the door contactconnection at MDF .
8/22/2019 bsnlppt
8/28
THEMAINPARTSOFTHEPOWERROOMARE:
1. BATTERIES
2. UPS (UNINTERRUPTED POWER SUPPLY)
3. CHARGING - DISCHARGING UNIT
4. INVERTERAND CONVERTER UNIT:
POWER PLANT :
8/22/2019 bsnlppt
9/28
SWITCHING ROOM :
Switch room consists of BM and CMcabinets mounted in standard switch.
These cabinets are fastened to a switchRoom and interconnected by cables.
8/22/2019 bsnlppt
10/28
.
MAIN DISTRIBUTION FRAME
> The primary function of MDF is to remove fault. It
is also known as Fault Remove Section.
> The telephone numbers are also disconnected inthe MDF because of some specific reason.
ORGANISATION OF THE MDF
Vertical side Horizontal side
8/22/2019 bsnlppt
11/28
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 core1 core = 4 bunch
1 bunch = 2 line
N.E.:-The word NE stands for the NUMBER OF EQUIPMENT.
It is used for testing number and
WEDGE: Wedge is used as a device for checking the ring. Wedge isplaced in jack strips, which is connected to telephone for checking.
8/22/2019 bsnlppt
12/28
HORIZONTAL SIDE:
The horizontal side connected to the underground cable.This cable is having 100 pairs. These pair is distributed
when we 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.
8/22/2019 bsnlppt
13/28
CONSTRUCTION OF M.D.F:-
Main distribution frame is mainly divided intwo parts.
(1) Vertical Side or Line side.
(2) LEN side or Exchange side.
8/22/2019 bsnlppt
14/28
VERTICAL SIDE:All the part from vertical side to the subscriber are generallycalled outdoor section.:
1. One vertical has 10 tag blocks.
2. Each tag block has 10 rows and each row has 10 tags. So
each tag block has 100 tags.
3. Connection between vertical side & subscribers are
provided by jelly filled cables.
4. These wires are first terminated in cabinet box, then
according to requirements the group of the wires (e.g. 200
wires, 100 wires etc.) is terminated in pillar box
8/22/2019 bsnlppt
15/28
LEN SIDE:
All the parts from LEN to the exchange is called indoorsection.
The connection of subscriber from exchange is
terminated on this side of MDF.
In 1 tag block there are 128 tags. Each tag block is
divided in 4 segments. That is 0, 1,2 & 3 and in each
segments.
8/22/2019 bsnlppt
16/28
.DIFFERENT TYPES OF FAULTS:-
LOOP FAULT:-IFTWOWIRESAREJOINEDTOGETHERBECAUSEOFIMPROPER
CONNECTION,
STORMINGAIRETC.
EARTH FAULT:-IFTWOWIRESGETSCRAPEATSOMEPLACESANDIFTHIS
WIRECOMESINCONTACTWITHTREE, PILLARORANYMETALOBJECTSTHENTHISTYPEOF
FAULTOCCURS.
CABLE FAULT:-FOROUTDOORCONNECTIONS, JELLYFILLEDWIRESARE
USEDWHICHAREAFFECTEDBYNATURALCAUSESSUCHASRAIN, EARTHQUAKEETC. ATSUCHTIMETHISFAULTOCCURS.
DISCONNECT FAULT:-THISTYPEOFFAULTOCCURSDUETOTHEBREAKING
OFWIRESBETWEENTHEVERTICALSIDE & LEN SIDE.
8/22/2019 bsnlppt
17/28
PROTECTIVE DEVICES USED IN M.D.F.Fuses
Gas Discharge Tube(G.D Tube)
Insertion Tool
Wires
8/22/2019 bsnlppt
18/28
OCB
The new switching systems are based on Stored ProgramControl concept. The call processing programmers are
distributed over different control organs of the system and are
stored in ROM/RAM of the units Processor in the control units
.
Features: 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).
8/22/2019 bsnlppt
19/28
GLOBAL SYSTEM FOR MOBILE COMMUNICATION(GSM)Global system for mobile communication (GSM) is a globally
accepted standard for digital cellular communication. GSM is
the name of a standardization group established in 1982 to
create a common European mobile telephone standard
GSM is a cellular network which means that mobilephones connect to it by searching for cells in the immediate
vicinity.GSM operates in the 900 MHz frequency band.
8/22/2019 bsnlppt
20/28
THEREAREFIVEDIFFERENTCELLSIZES INA
GSM NETWORK-
Macro CellsMicro Cells Pico Cells Femto Cells
Umbrella Cells
8/22/2019 bsnlppt
21/28
GSM : (SYSTEM ARCHITECHTURE)
This system structured hierarchically as shown:
It consist of one administrative region, which is assigned
to a MSC(Mobile Switching Center). Each administrative Region is made up of atleast one
Location Area(LA). LA is also called the visited area.
An LA consists of several cell groups.
Each cell group is assigned to a base stationcontroller(BSC).
Cells of one BSC may belong to differentLAs.
8/22/2019 bsnlppt
22/28
GSM : (SYSTEM ARCHITECHTURE)
8/22/2019 bsnlppt
23/28
BASIC BUILDING BLOCKS:
Mobile Station (MS)
Base Station (BS)
Mobile services Switching Center (MSC)
Databases
Operation and Maintenance Center (OMC)
8/22/2019 bsnlppt
24/28
SYSTEM CAPACITY
Shannons Theory predicts the maximum amount of
information that can be transmitted over a channel with
given BW & SNR.
The optimum usage of given BW is obtained when the
signal are noise like & min SNR.
Hence for increased capacity the choice isCDMA.
8/22/2019 bsnlppt
25/28
MEDIA : -
1.Carrier system
2. Co-axial Cable
3. Optical Fiber Cable(OFC).
4. Satellite.
8/22/2019 bsnlppt
26/28
PROCEDURE FOR HANDLING
SUBSCRIBER COMPLAINTS
Telephone Dead:
Case--I Problem concerns a particular subscriber.Case-II Quit a few numbers of telephone reported dead:
Telephone Held-Up ( No Dial Tone ):
8/22/2019 bsnlppt
27/28
> PERMANENT RING
> PERMANENT DIAL TONE
> PERMANENT BUSY TONE
> PERMANENT RING TRIP
>SPEECH QUALITY POOR
> WRONG NUMBERS
> ONE WAY SPEECH
> RINGER CADENCE
8/22/2019 bsnlppt
28/28
THANK YOU
