6 WEEEKS TRAINING REPORT UNDER 4 DEPARTMENTS OF INDIAN RAILWAY

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PRACTICAL TRAINING REPORT
ON
COMMUNICATION AND SIGNALLING
AT INDIAN RAILWAYS
SUBMITTED BY:
AMEYA VASHISHTH (2013-311-009)
B.Tech ( IT) 7TH
SEMESTER
JAMIA HAMDARD

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4B
ACKNOWLEDGEMENTS
Any collateral activity cannot be truly finished without the help &
enthusiasm of the supervisors involved. Additional technical assistance were
provided by many individuals.
I would like to express the deepest appreciation to the CCM(Signal &
Telecommunication), Mr. P.K. JAIN AND Mr. Yudhishtar Suryan (CPO) for
the guidance and persistent throughout the training period.
Also, I would like to thank the NR employees who elaborated the
technical details of the various technologies ongoing in their department.
It has been a pleasure working with the NR, Delhi in the
enhancement of my technical knowledge. I owe gratitude to many
individuals involved in the development of this report.

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PREFACE
Engineering students gain theoretical knowledge only through books. Only
theoretical knowledge is not sufficient for absolute mastery in any field.
Theoretical knowledge in our books is not of much use without knowing its
practical implementation. It has been experienced that theoretical knowledge is
volatile in nature; however practical knowledge imparts solid foundation in our
mind.
We have covered in this report the history ,latest developments in Railway
IT interface as well as related fields. We have studied the various uses of IT in
railways like PRS,DataLogger, IVRS,FOIS and CRIS. We have also covered the
RailNet, its objectives, various phases of implementation, utility of RailNet and
various issues in RailNet.
This report is infact a summary of, what I have learnt and seen during my
training in “NORTHERN RAILWAY,DELHI.” Succeeding chapters give details
what I have learnt in HQ Office, IRCA BUILDING, DELHI
AMEYA VASHISHTH
B.Tech 7th
Semester
Information Technology

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Table Of Contents
Indian Railway(organizational structure) ________________ 1
Signaling _______________________________________________ 3
DataLogger _____________________________________________ 9
Train Charting ___________________________________________ 12
Passenger Reservation System ________________________ 15
IVRS _____________________________________________________ 16
Microwave Communication ________________________________ 20
Railnet____________________________________________________ 22
Optical Fiber Communication _____________________________ 30
OFC Network at IR ________________________________________ 33

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INDIAN RAILWAY
INTRODUCTION:-
Indian Railway (Hindi: भारतीय रे ल) is the state-owned railway company of India,
which owns and operates most of the country's rail transport. It is overseen by the
Ministry of Railways of the Government of India.
India boasts one of the world’s largest railway network in the world. Every day, 20
million people travel around the country in hundreds of trains running between various
stations smoothly and safely.
The formal inauguration ceremony of IR was performed on 16th April 1853 with
the first passenger train steamed out of Howrah station destined for Hooghly, a distance
of 36 km, on 15th August, 1854 .
Snapshots:-
It encompasses 6,909 stations over a total route length of more than
63,028 kilometres of route length and a track length of 111,600 km .
It is one of the world's largest commercial or utility employers, with more than
1.6 million employees.
It grossed a revenue of ` 88,355 cr and bagging a net income of ` 951 cr in the
financial year 2014-15 .
It moves 2 million tons of freight & 20 million people daily across the county
with the help of 200,000 (freight) wagons.
7,000 passenger trains across the country services 20 million people to their
destinations .
A.K. MITTAL is the current Chairman of Railway Board .
Organisational Structure:-
IR is a department owned and controlled by the Government of India, the
Ministry of Railways . IR is administered by the Railway Board, which has a financial
commissioner, five members and a chairman.

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Railway zones:-
IR is divided into zones, which are further sub-divided into divisions. The number
of zones in Indian Railways increased from six to eight in 1951, nine in 1952, and finally
16 in 2003. Each zonal railway is made up of a certain number of divisions, each having
a divisional headquarters. There are a total of 67 divisions under 16 zones , presently
operating in the country .
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Name Headquarters Divisions
Central Mumbai Mumbai, Bhusawal, Pune, Solapur, Nagpur
East Central Hajipur
Danapur, Dhanbad, Mughalsarai, Samastipur,
Sonpur
East Coast Bhubaneswar Khurda Road, Sambalpur, Visakhapatnam
Eastern Kolkata Howrah, Sealdah, Asansol, Malda
North Central Allahabad Allahabad, Agra, Jhansi
North Eastern Gorakhpur Izzatnagar, Lucknow, Varanasi
North Western Jaipur Jaipur, Ajmer, Bikaner, Jodhpur
Northeast Frontier Guwahati Alipurduar,Katihar, Lumding, Rangia, Tinsukia
Northern Delhi Delhi, Ambala, Lucknow, Moradabad
South Central Secunderabad Secunderabad, Hyderabad, Guntakal, Guntur,
Nanded, Vijayawada
South East Central Bilaspur, CG Bilaspur, Raipur, Nagpur
South Eastern Kolkata Adra, Chakradharpur, Kharagpur, Ranchi
South Western Hubli Hubli, Bangalore, Mysore
Southern Chennai
Chennai, Madurai, Palakkad, Salem,
Tiruchchirapalli, Thiruvanathapuram
West Central Jabalpur Jabalpur, Bhopal, Kota
Western Mumbai
MumbaiCentral, Vadodara, Ratlam,
Ahmedabad, Rajkot, Bhavnagar
Each of the 16 zones, is headed by a General Manager (GM) who reports
directly to the Railway Board.
The zones are further divided into divisions under the control of Divisional Railway
Managers (DRM). The divisional officers of engineering, mechanical, electrical, signal
and telecommunication, accounts, personnel, operating, commercial and safety branches
report to the respective Divisional Manager and are in charge of operation and
maintenance of assets.
Further down the hierarchy tree are the Station Masters who control individual stations
and the train movement through the track territory under their stations' administration.

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Principles of Train working and need for signaling:-
All over the world Railway transportation is increasingly used, as this mode of
transport is more energy efficient and environmentally friendly than road transportation.
Trains move on steel rail tracks and wheels of the railway vehicle are also flanged Steel
wheels. Hence least friction occurs at the point of contact between the track & wheels.
Therefore trains carry more loads resulting in higher traffic capacity since trains
move on specific tracks called rails, their path is to be fully guided and there is no
arrangement of steering . Clear of obstruction as available with road transportation
so there is a need to provide control on the movement of trains in the form of Railway
signals which indicate to the drivers to stop or move and also the speed at which they can
pass a signal.
Since the load carried by the trains and the speed which the trains can attain are
high, they need more braking distance before coming to the stop from full speed. Without
signal to be available on the route to constantly guide the driver accidents will take place
due to collisions

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There are basically two purposes achieved by railway signaling :
To safety receive and dispatch trains at a station.
To control the movements of trains from one station to another after ensuring that
the track on which this train will move to reach the next station is free from
movement of another train either in the same or opposite direction.
Apart from meeting the basic requirement of necessary safety in train operation, modern
railway signaling plays an important role in determining the capacity of a section .The
capacity decides the number of trains that can run on a single day. By proper signaling
the capacity can be increased to a considerable extent without resorting to costlier
alternatives.
The essential components of railway signaling:
The fixed signals provided by the side of the railway track with indication in the
form of colour lights are the actual authority to a driver to get in to the portion of
the track beyond the signal. At stations the trains may be received on any one of
the platform lines.
To take the train to any specific track, points are provided. The purpose of the
point on the track is to divert the train from one track to adjacent one. Hence the
signal has to be connected to the points in an arrangement called interlocking.
This Interlocking arrangement only ensures that a point is correctly set for the
particular route or a track and the signal conveys this information to the driver.
Trains run on dedicated line .A line consists of two rails running parallel to each other.
This is also called “Track”.
Track:-
Indian railways uses 4 gauges:-
Broad Gauge – It is 1,676mm of 5'6” wide & operational in most parts of
the country with 96,851 km of track length (86.8% of entire track length of
all the gauges) .

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Standard Guage – It is smaller than the above with 1,435mm width.
Metre Guage - It is ,obviously, 1,000mm wide common in regions with
less traffic, such as hilly areas.
Narrow Guage – It is 610 mm wide .
Track sections are rated for speeds ranging from 75 to 160 km/h.
The track is represented in Signaling plans by a single line as shown below.
In station yards there will be more than one track for receiving and dispatching trains.
Points are provided to divert the running trains from one track to another. The points
have movable switches which can be operated electrically by a point machine.
A point can be single-ended point or double-ended point depending on whether the
movable switches are provided at one end or two ends of the point,

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The two switch rails of the point are rigidly connected together by a cross bar so that they
can be moved from one position to the other position together by the point machine. If
the position of the switches is such that the train is moved on to the main line as shown
above, then the point is said to be in its normal (N) position.
If the switch rails are moved to the other position as shown below so that the train is
diverted to the loop line, then the point is said to be in its REVERSE (R) position.
In both the above cases, when one switch rail is closed with its stock rail, the other switch
is open. In either case, the opening shall be 41/2”. Between the closed switch and its
stock rail not more than 1/8” gap, is permitted.

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The centre to centre distance between the adjacent tracks (between main line to
the adjacent loop line or between one loop line and other adjacent loop line) shall not be
less than 14”0’. Where cross-over pints are provided between adjacent tracks, this
distance gets reduced. At the place where it is less than 14”, one track may foul the other
track. At this point a ‟fouling Bar” (a cement lab of about 5” length with inscription
“FOULING MARK” is provided.
When a train drawn on a track, it should stand clear of the FOULING MARK as
otherwise, the train may foul the movement of train on the adjacent track, thereby
causing a side-collision.
Clearance of track:
Since a train cannot be received on the portion of track where another train is
standing on same portion of the track, the signal before it is cleared for the movement of
a train has to ensure the track clearance. There are equipments used in Railway signaling
to achieve the above safety condition.
Types of Signals:
Signal:
Signal is a medium to convey a particular pre-determined meaning in non-verbal form.
Multiple Aspect Color Light Signal (MACLS):
Multiple means more than 2 indications .They may have 3 or 4 different aspects or
indications to be given to the driver. These signals have longer range of visibility and
Improved reliability.

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Classification of CLS:

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Data Loggers/Train Monitoring Systems:-
Train Monitoring System monitors the movements of trains within the control
section from remote control room and graphically simulates online Status of the multiple
stations (Digitized Yard Layouts with Train Movements) in LCD Monitors.
More than one Station yard Layout can be viewed in each Monitor depending on the size
of the Yard.
The IR uses Datalogger, Delphi developed by Efftronics Pvt. Ltd., Vijayawada .
Delhi uses services of Dataloggers since '98 .
➔ Technically speaking, a data logger is any device that can be used to store
data. This includes many data acquisition devices such as plug-in boards or
serial communication systems which use a computer as a real time data
recording system.
➔ However, most instrument manufacturers consider a data logger a standalone
device that can read various types of electrical signals and store the data in
internal memory for later download to a computer.
➔ The advantage of data loggers is that they can operate independently of
a computer, unlike many other types of data acquisition devices.
➔ Contemplating over the fact that 98% of accidents happen due to
incorrect signal perception, datalogger serves as a boon to thwart such
fallacies .
Data loggers are available in various shapes and sizes. The range includes simple
economical single channel fixed function loggers to more powerful programmable
devices capable of handling hundreds of inputs.
➔ Data logging is now a standard technique within railway signaling engineering for
both safety and performance management purposes .
➔ Data logging facilitates the past analysis of any event . Also improving upon the
reaction time of any event .
➔ Dataloggers facilitates the continuous monitoring of track, trains, etc.

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Features :-
➔ Online Graphical Display of Status of all the Board Station yards for efficient
control.
➔ Online Status of all auto sections for effective planning and monitoring of train
movements.
➔ Online status of various assets like points, signals, Shunt signals, crank handles,
Gates, Axle Counters, Route Relays and Knobs.
➔ Route Set Indication.
➔ Details of Train like Train No. / Name passing through a station.
➔ Details of train(s) in auto section.
Technical Details :-
➔ Embedded system built on Motorola 68000 microprocessor.
➔ LCD, LED and Keyboard user interface .
➔ Min 512 - Max 4096 opto isolated digital input @ 16 mSec sampling. ? 96
individually isolated analog input voltage/current channels @1 Sec .
➔ Nonvolatile data storage in flash ram and 8 serial ports for data network .
Network Management:-
➔ Front end application software at central control place.
➔ Link status of all the dataloggers in the network.
➔ Online status of digital/analog inputs.
➔ Data selective viewing.
➔ Online graphical mimic display of every station layout. Auto backup on exceeding
configured size of data base.

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Cost savings
The deployment is the most cost-effective data logging solution, from level crossing to
major interlocking schemes. Key savings are offered from:
➔ Ease of installation
➔ Low maintenance
➔ Integration of UPS, modem, display and input cards
At the most compact end, a 48 or 96 channel unit will monitor a level crossing.
For larger installations up to 8 units can be connected together, enabling 3072 channels to
be monitored simultaneously. All systems use the same common platform resulting in
economies of production.
Recorded data can be accessed using a standard web browser. For advanced remote
analysis and diagnostic features (such as slow moving point alarms or SPAD
investigations), a software plug-in has been developed for the Balfour Beatty Rail Asset
View system.
In addition, it has a touch screen LCD to allow maintenance technicians to access data
directly on site. This removes the need for an inconvenient laptop computer or separate
handheld terminal.
Reliability:-
Contained within the unit is a fully functional Uninterruptible Power Supply giving six
hours of battery backup in the case of mains failure.
Low power consumption means that no cooling fan is required, which in turn means there
are no dust filters to clean or moving mechanical parts to fail. If maintenance is required, the
entire unit can be removed simply by disconnecting the input leads and a mains plug.
Safety:-
The Delphi, has been designed specifically to meet the stringent safety requirements of
railway signaling applications. All digital and analog input channels are opto isolated to a
minimum of 1kV.

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DATALOGGER BASED COMPUTERISED TRAINCHARTING
INTRODUCTION:-
All the stations on Delhi- Amritsar route of Delhi Division are equipped with data
loggers.
Data loggers are networked as per control sections.
In Delhi- Amritsar section 23 stations are provided with 25 data loggers.
Since the information of the vital relays is available at Control Office i.e. Delhi. It is
possible to track a train and to chart the train movement automatically.
The system is not only track the train but also predict the train movement for the
next few hours, which is equivalent to the manual planning by the MTNL. Based on the
train information & charting data various statistics can be generated in the form of
reports which are time consuming & tedious if done manually.
SETUP:-
Entire Rajdhani route of DELHI division (having 62stations, 549Kms) have been
provided with Networked Data loggers.
All the Data loggers are connected through existing RE telecom cable in series to FEP.
The FEP of the Data logger Network is connected to the Servers through a computer
containing NMDL software with Train charting logics. (See Fig: 1-System
Configuration) The client software is provided for viewing the chart / data. This client
software by default is a passive client (which doesn’t enable chart editing & manual
entry) but on accessing into higher levels by issuing passwords it acts as an active client
(which enables chart editing & manual entry provisions).
Active Client maintained by ATNL who has the control over the train movements and is
connected to the server through LAN. At any time, active Client can control the train
movement charting. Active Client can feed the Train information as shown in
Passive Clients to view the chart anywhere from the network, the chart available at this
client is unchanged and cannot be modified. Any number of passive clients can view the
train chart by connecting to the server.

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System Configuration
Automatic Tracking of Train:
For tracking a train movement, basic concept of sequential operation of track
circuit is monitored along with the position of points en-route. For this purpose all
Exit/Entry routes are tabulated in terms of Geographical position of Track circuits &
point position, station wise.
➔ Whenever any T.C. is dropped it activates the route, which contains that track
circuit. As the train moves, track circuits will drop sequentially & finally only one
unique route will be selected.
➔ At this stage this train will be allotted train index Automatically for further
identification of the train.
With the point position and the berthing track position it can be determined that
what line / platform the train is received.
➔ Similarly when the train leaves the station, it will select the appropriate exit route.
When this train touches the Home Signal track of next station it checks if prior to
this AZTR of Block section in rear & the Advance Starter track of previous station
were dropped. This is co-related the station-to-station train charting. Since the
train index is carry forward in this process, it is therefore possible to plot the
correct train.

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The train charting software facilitates the ATNL to enter the train No., and other
train information such as Loco / Engine No., Driver’s name, load, Guard’s name,
vacuum, etc. This software also facilitates to edit the train charting whenever necessary.
It allows making links if joints in auto mode.
It allows charting manually even if Automatic charting is partially or totally failed. For
the convenience of ATNL two monitors are provided. One screen always shows the chart
and another is used to open the manual-charting string grid or to pop-up other forms.
FEATURES:-
➔ Auto tracking of train on real time.
➔ Online Plotting of chart.
➔ Charting of train from starting to destination point.
➔ Alarm generation & tracking of any new train entered in the section automatically.
➔ Reporting of deviation from scheduled timings.
➔ Useful tools are available – Link, Delink, Draw blocks & Line with UNDO,
Comments on Graph, Highlighting train, Searching train etc.
➔ User can select maximum 14hrs chart (7hrs of current chart + 7hrs of prediction).
➔ Transparent Control system. Anyone can monitor control chart in control office on
LAN.
Advantage through Datalogger based Traincharting:-
➔ Controller can devote more time on planning .
➔ Plotting is on Real time. No human involvement to plot the train so more accurate.
Online loop occupancy position .
LIMITATIONS OF AUTOMATIC TRAIN CHARTING SYSTEM:-
➔ Networking communication media should work perfectly to maintain on-line
status.
➔ All the stations of the control section should be equipped with Data logger.
➔ Train controllers should have basic computer knowledge.

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➔ Continuous track circuiting required.
COMPUTERIZED PASSENGER RESERVATION
SYSTEM
INTRODUCTION:
➔ The IR carries about 5.5 lakh passengers in Reservation reserved accommodation
every day.
➔ The computerized Passenger Reservation System (PRS) facilitates booking and
Cancelling of tickets from any of the 4000Terminals(i.e. PRS booking
windows)all over the country.
➔ These tickets can be booked or cancelled for journeys commencing in any party of
India and ending in any other part ,with travels times as long as 72 hour and
distances up to several thousands kilometre.
➔ There are mainly 5 servers in INDIA. These are New Delhi, Kolkata, Channai,
Mumbai & secunderabad
EQUIPMENTS:
The equipment used in PRS are --
➔ Modem
➔ Multiplexing Equipment
➔ End terminal.
MODEM
Modem are used for communication various computer or between Computer
& terminals over ordinary or leased(dedicated ) telephone lines.
We can use modems to log on to micro, mini, main frame computer for line processing.
We can use them to connect two remote computers for data.
How does modem works
➔ The word modem in feed is derived from the words modulate &
demodulator.
➔ Computer communicate in digital languages while telephone lines
communicate in analog language. So an inter mediator required which can
communicate both these language .

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➔ Modem transmits information between computer bit by one stream. To
represent a bit (or group of bits), modem modulates the characteristics of the
wave that are carried by telephone lines.
➔ The rate at which the modem change these characteristics determines the
transmission speed of data transmission .The rate of modem is called bound
rate of modem.
➔ The bound rate of modem is bits per second. In advance modulation such as
quadrature amplitude modulate 4 bits & transmitted it in each band. Thus the
speed of the modem transmitting at 600 band would be 2400 bps.
➔ The modems can transmit data in two formats: Asynchronous &
Synchronous.
➔ The analog modem switch at each location is connected to analog modems
of the main as well as the stand by links. If the main links fails , the switch
units at either end switch the user equipment at the stand by link. When the
main links get restored, the analog modem switches the user equipment
back to main link.
Multiplexing Equipment:-
There are two type multiplexing equipments for each channel.
The multiplexer used may be of 8-ports or 16-port .The data is get multiplexed at the rate
of the 96KBps. The multiplexing generally of analog type.
End Terminal:-
The end terminals of system is the station where the tickets to be Printed out .
The terminal consists of a computer system with a dot matrix printer. The number of the
total end terminal at the station can be increased or decreased according to the
multiplexing used.
IVRS (Interactive voice response system)
INTRODUCTION:
➔ The system in which, the information available in the computer is retrieved by
the user in the form of voice with the help of the interaction between telephone
and computer is known as Interactive Voice Respond System (IVRS).
➔ With the help of this system information regarding public reservation;
arrival /departure of train; fare can be delivered to user when and where it is
asked through telephone.

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➔ Each section control office is having a computer called DATA ENTRY
COMPUTER along with dial up/lease line modem which is used for linking the
computer of other control offices either directly or through server available at
Church Gate . Each control office computer is identified as check / data entry
point. Information regarding the running of the train can be registered or
checked at every 15 minutes duration.
➔ At place where the information is to be retrieve through Telephone, an another
computer is linked with data entry computer called IVRS COMPUTER, which
is connected to data entry computer by ETHERNET CARD. These computers
read the information from data entry computer and then convert it to voice for
user purpose.
HARDWARE
DATA ENTRY TERMINAL
It is a personal computer of more than 166 MHz with 16 MB RAM; 2.1 GB Hard
disk; 101 key keyboard; a mouse & a colour monitor.
MODEM
The data entry terminals are linked with lease line/ dialup modem of speed better
than 33.6 KBPS.
IVRS TERMINAL:
It is Pentium 133 MHz P.C. with 24 port dialogic cards called IVRS card capable
to respond on both pulse and tone. Out of 24 ports –4 ports are used for voice and FAX
on demand; 2 ports are used for railway PSTN lines; 2 ports are used for fare inquiry and
rest 16 ports are used for train inquiry.
SOFTWARE:
There are three types of software.
It is friendly user software, which is used to record the train schedule
timing information in data files.
This software is having following facilities,
(1) The system is secured by 3 stages of password facility.

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(2) It is having the facility for data entry of running/schedule time.
(3) Entry for expected arrival/ departure.
(4) Addition and removal of data entry points.
(5) Addition and removal of train in the system.
(6) Changes in the database for timetable; fare table etc.
(7) This software is having a facility to generate the report of
(a) Status of running train as per—
➔ According to train
➔ According to control office
➔ As per a specific interval
(b) Information of train, when the train is late more than specific hours.
(c) Summary of any train running over the month.
(d) It also shows the train graph.
(8) It restricts the entry of train after a specific period i.e.the file is deleted for a
train after 2 hours of its arrival; and deletes the files which are 48 hours old and
restructure/reorganize the files.
COMMUNICATION SOFTWARE:-
This software works on the principle of packet switching in which each train file
is developed in the form of packet along with destination address.
In IVRS system Mumbai Central computer acts as HUB and it will dial or
connect through lease line after a specific interval to the data entry computers of
different control offices and exchange the files with them.
When a pop file is generated after every 15 minutes in data entry computer, then
file is transferred to its queue directory. When HUB computer is connected to data entry
computer, HUB searches the files from queue directory and then down load in its
receive directory and similarly the queue directory files available in HUB will be
received and stored by data entry computer. By this way the queue directory files are
exchanged and updated.

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The communication software is also having the facility for CRC check (cyclic
redundancy check) and receive check. So in case of line failure or modem faulty,
when the file could not be exchanged, then HUB try to establish the link and if is not
able to exchange, then it will create alarm; and show link break
The important facilities of communication software: -
1) Auto dialing facility for origination of transmission of information or data.
2) Having facility of auto pickup of file from remote queue directory.
3) Facility of auto transfer of own file to remote/required place.
4) Facility of transfer of file as per priority decided by HUB.
5) It has facility to support WAN and is capable of interfacing with any type
of communication system like Internet, VHF; UHF, leased line.
6) Facility of monitoring of trans. and receive file.
7) It is provided with the list of transmitted files and remaining files.
OLTRIS SOFTWARE:-
The main aim of the system is to provide “ON LINE TRAIN RUNNING
INFORMATION” like termination of the train before schedule ; changed the route of
the train; accident of train; abnormal delay/late of the train and so on. So the software is
developed to support all the abnormal activity.
This software is having the following facilities:
a) It is having the facility to interact with both pulse and tone users.
b) It is having a facility of FAX on demand, for that separate terminal is provided.
c) It is supporting and select more than one language.
d) According to traffic, ports can be increased or decreased.
e) It is having the facility of mailbox.
f) It is having the facility of according the calls on each port and give a report of
no. of calls in 24 hours and the calls in a specific period.
Overhead lines or overhead wires are used to transmit electrical energy to trams,
trolley, buses or trains at a distance from the energy supply point. In this article the
generic term overhead line is used Overhead line is designed on the principle of one or

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more overhead wires situated over rail tracks, raised to a high electrical potential by
connection to feeder stations at regular intervals. The feeder stations are usually fed from
a high-voltage electrical grid.
Microwave Communication
Introduction:-
The objective of microwave communication systems is to transmit information
from one place to another without interruption, and clear reproduction at the receiver.
Fig. indicates how this is achieved in its simplest form.
➔ Above 100 MHz the waves travel in straight lines and can therefore be narrowly
focused. Concentrating all the energy into a small beam using a parabolic antenna
(like the satellite TV dish) gives a much higher signal to noise ratio, but the
transmitting and receiving antennas must be accurately aligned with each other.
➔ Before the advent of fiber optics, these microwaves formed the heart of the long
distance telephone transmission system.
➔ In its simplest form the microwave link can be one hop, consisting of one pair of
antennas spaced as little as one or two kilometers apart, or can be a backbone,
including multiple hops, spanning several thousand kilometers.
➔ A single hop is typically 30 to 60 km in relatively flat regions for frequencies in
the 2 to 8 GHz bands. When antennas are placed between mountain peaks, a very
long hop length can be achieved. Hop distances in excess of 200 km are in
existence.
➔ The "line-of-sight" nature of microwaves has some very attractive advantages over
cable systems. Line of sight is a term which is only partially correct when
describing microwave paths.

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➔ Atmospheric conditions and certain effects modify the propagation of microwaves
so that even if the designer can see from point A to point B (true line of sight), it
may not be possible to place antennas at those two points and achieve a
satisfactory communication performance.
In order to overcome the problems of line-of-sight and power amplification of
weak signals, microwave systems use repeaters at intervals of about 25 to 30 km in
between the transmitting receiving stations.
➔ The first repeater is placed in line-of-sight of the transmitting station and the last
repeater is placed in line-of-sight of the receiving station. Two consecutive
repeaters are also placed in line-of-sight of each other.
➔ The data signals are received, amplified, and re-transmitted by each of these
stations.
Microwave Transmitter and Receiver
Below figure shows block diagram of microwave link transmitter and receiver section --
➔ The voice, video, or data channels are combined by a technique known as
multiplexing to produce a BB signal. This signal is frequency modulated to an IF
and then up converted (heterodyned) to the RF for transmission through the
atmosphere.
➔ The reverse process occurs at the receiver. The microwave transmission
frequencies are within the approximate range 2 to 24 GHz.
➔ The frequency bands used for digital microwave radio are recommended by the
CCIR. Each recommendation clearly defines the frequency range, the number of
channels that can be used within that range, the channel spacing the bit rate and
the polarization possibilities.

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RAILNET
The Indian Railways is Asia's largest and the world's second largest rail
network. Adopting e-Governance in right earnest and to reap the benefit of IT explosion,
Indian Railways have established a 'Corporate Wide Information System' (CWIS)
called RAILNET, abbreviated as RN henceforth.
It provides smooth flow of information on demand for administrative purposes,
which would enable taking quicker and better decisions.
Realising the important role that information plays in customer services and in
railways operations, IR had embarked on its computerisation program. IR developed a
dedicated skeletal communication network, as a basic requirement for train operation.
RN was established in Kota Division in '99 .
After the early introduction of basic computer applications e.g. Pay rolls,
Inventory Control and Operating Statistics, Railways went for deployment of computers
for productivity improvement through building up operational databases.
Use of IT in Railway :-
➔ Passenger Reservation System (PRS)
CONCERT (Country -wide Network of Computerised Enhanced Reservation
& Ticketing) , Indian Railways fully automated PRS software, is a complex online
distributed transaction application based on client server architecture interconnecting the
regional computing system into a National PRS grid.
The salient features of CONCERT software include allowing passenger from
anywhere to do a booking for a journey in any train in any class from anywhere to
anywhere; handling reservation,modifications cancellation/refunds.
➔ e-Ticketing
CRIS (Centre for Railway Information System) has successfully developed the
Internet ticketing solution launched by IRCTC (Indian Railway Catering and Tourism
Corporation).

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The effort involved interfacing the IRCTC front end with backend PRS Alpha
servers, writing procedures for search and queries at the backend, ticket printing on
existing clients and accounting software.
➔ UTS (Unreserved Ticket System)
UTS is the complete solution for computerised unreserved ticketing from
dedicated counter terminals and replaces manual Printed Card Tickets/Excess Fare
Tickets/Blank Paper Tickets. In future, ticketing from handheld terminals smart card,
automatic vending machines, etc. is also envisaged.
➔ IVRS (Interactive Voice Response System)
IVRS is a telephonic enquiry system which information such as Passenger Name
Record (PNR) enquiry, Train Arrival/Departure information enquiry through NTES, and
Berth availability position in any train, in multiple languages.
➔ NTES (National Train Enquiry System)
NTES provides arrival/departure as well as current status information about
any passenger train in the entire Indian Railways . NTES is parallel to PRS.
The servers are located at five metros i.e. Delhi, Kolkata, Mumbai, Chennai,
Secunderabad and all are interconnected.
Entries are made regarding running of train every half an hour at various locations
including divisional headquarter all over the Indian Railways.
NTES is used by IVRS and other web enabled services and mobile services for providing
train information to the public.
RAILNET MIS :-
For running any business organisation, the efficiency of the MIS is very
important. Indian Railways have many areas, where use of IT is going to have a telling
effect. Some of these are listed down:
Rail Budget Compilation System (RBCS):-
CRIS has developed RBCS for collecting budgetary inputs from the different
zones and production units of the Indian Railways. The system facilitates capturing of

28. 28
data, building of database, analysis of demands and pruning of the estimates for inclusion
in the Railway Budget.
Besides MIS reports, the system enables printing of budget documents in
bilingual, Hindi and English. This system is implemented at 88 locations spread over
Zonal Railways and Production Units apart from Railway Board.
Comprehensive Payroll Processing System (CPPS):-
CPPS is a comprehensive bilingual package generating monthly salary bills
including Incentive Bonus Calculation and Labour Accounting modules and pay slips in
Hindi.
Vigilance Software System (VSS):-
VSS is designed specially for the requirements of Vigilance Department of Indian
Railways and has been implemented in all the Vigilance Departments of Indian Railway
Zonal Headquarters.
VSS maintains information about vigilance cases/complaints includes various reports,
forwarding letters generated by Vigilance Department and keeps track of Receipt.
Material Management Information System for P-Way material:-
This package is designed specially for the requirements of Civil Engineering
department of Indian Railways and helps the users in accounting' stores for P-Way
materials. Special emphasis has been given to scrap disposal.
Comprehensive Accounting & Transaction System (CATS):-
CATS has been designed with common database to address functionalities for
both personnel and Finance Departments. CATS contain two major modules Financial
Accounting System (FAS) and Payroll System (PS).
ORGANIZATION:-
First Rail-Net was established between RAILWAY BOARD, 9 Zones, and 6
production units in phase 1.
Then extended to 6 new zones, 5 centralized training institutes, research and
development and standard organizations, Metropolitan transport project in phase 2.

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The divisional offices, Zonal training institutes will be connected to rail net in phase 3
and finally to station, yards, shads etc.
RN comprises of -
1. Intra-net
Intra-net is an internal network of Indian railway allowing the railway
officers and staff to communicate on this digitized network .
2. Inter-net
Internet allows user to get into a global communication method and global
pool of knowledge, advertisement and entertainment through www (World Wide Web) in
a secured manner.
TOOLS:-
E-Mail
EDI (Electronic Data
Interchange) WWW
FTP (File Transfer Protocol)
TCP (Transmission Control Protocol)
OBJECTIVES:-
Railnet is used to provide following services :
Creation of Web
pages. E-mail.
Electronic transfer of data used for monitoring and coordination
purpose. Voice-over IP.
Video-conferencing
Web-based application software development
Web surfing (Browser usage for internet and intranet).
HARDWARE COMPONENTS:-

30. 30
‘Compaq’ Servers.
‘CISCO’ Routers, Switches & Hubs
Structured cabling using UTP-Cat 5 cabling (10 MBPS) (Maximum distance
permissible 100 meters between )
SOFTWARE COMPONENTS
MS Windows NT Server
Operating system for server
MS Windows NT Workstation 4.0
Operating system for workstations
Internet Information Server 3.0
Cisco Works with SNMPC
Provides safety to railway information.
HOW DOES RAILNET WORK?
Railnet is similar to internet. All the computers and communication cables that
make up the thousands of smaller networks at various railway offices are connected
together to form the railnet.
It follows a simple rule, TCP/IP. Here packet switching, where a computer
message is broken into small packets , is used . Each packet consists of a destination
address , a source address and packet identity and user data. A packet can travel through
any path on the network .
Different servers of railways are connected to each other via its own microwave
stations to form a nationwide network of Indian Railways.
Four wires are coming from microwave station and they are terminated on the
lease line modem. This modem is connected to router through a cable. Router is
connected to the switch.
Switch is an interface between server and router. Various hubs can be connected
in a cascade to increase the no. of terminations. This is a star topology.

31. 31
Hubs along with computers within the distance of 50 meter are terminated on the
switch. In this manner all the computers in the LAN can share the data and can
access the internet through server.
Router also provides the facility of Dial Up Networking . It can accommodate 8
dial tone modems which provide internet facility on distant computers.
Railnet Genral Arrangment
RAILNET NETWORK COMPONENTS
A. SERVER
A network is a multiuser system because more than one person at a time can send
requests to a machine. A shared machine together with the software programs , which

32. 32
handles requests and distributes the network resources such as data files and printer time
both the machine and its software are jointly referred as the server.
Server has following characteristics :
1) Hardware including motherboard of the server is entirely different from a normal
P.C.
2) It can be used with two processors of 500MHz.
3) It contains 3 hard disks having capacity of 9GB.These are connected to the
motherboard through RAD controller card .
4) A server should be able to implement security for its data.
5) It contains Microsoft Back Office Server 4.01 software which comprises following
programs:
a) Microsoft NT.
b) Microsoft BackOffice.
c) Site Management Server.
d) Proxy Software.
e) Service Network Administrator
f) Exchange Server.
B. ROUTER
A router translates information from one network to another; it is similar to a
super intelligent bridge. Routers select the best path to route a message, based on the
destination address and origin. The router can direct traffic to prevent head-on collisions,
and is smart enough to know when to direct traffic along back roads and shortcuts.
Routers know the addresses of computers, bridges, and other routers on each
side of the network. Routers can even "listen" to the entire network to determine which
sections are busiest, they can then redirect data around those sections until they clear up.
Routers can:
Direct signal traffic efficiently.
Route messages between any two protocols.
Route messages between linear bus, star, and star-wired ring topologies.
Route messages across fiber optics, coaxial, and twisted pair cabling.
C. SWITCH
The switch is used to interconnect the Nodes. But it is more complex and
versatile, and also there is no division of bandwidth among the nodes.
They are active device with following points :
(1) 10Mbps, 100 Mbps, single-speed, or dual speed operation.

33. 33
(2) Congestion control, which means that the switch should have enough buffers to
take care of the traffic peaks.
(3) Segmentation of local network
(4) Speed up the local network. They are of 8,16 or 48 ports active terminal.
D. FIREWALL
It is security purpose software, which is used to secure the server contents, so the
outside user could not temper the information. The user can read the information but can
not write anything.
E. HUB
It is active junction box, which is used to connect the nodes and all the servers
using any type of cable (UTP, Coaxial etc). It contains a division of network bandwidth.
The important parameters to be considered whole selecting are: -
Support for dual-speed operations.
Number and types of ports, UTP and
BNC. Auto switching.
Support a built-in segment switch.
Ease of configuration.
It can have a capacity of 8, 16 or 24 nodes and the maximum distance between
Hub and nodes is 100 Mt. If distance is more, then additional HUB must be used (but not
more than 3).

34. 34
Speeding the communication with
Optical Fibers
Today's general demands to railway administrations all over the world are:
improved traffic regularity,
more frequent departures and,
shorter travelling times.
In order to meet above demands it is paramount to expand the existing
transmission capacity for tele-communication and to implement more flexible signal
interlocking systems.
The telecommunication network has to operate with more subscribers as well as to
carry a number of new services, such as automatic train numbering, electronic
reporting and passenger information, freight control and voice channels to radio
base stations for
mobileradio communication.
The old relay based signal interlocking systems for line block interlocking have to be
replaced by cheaper and more flexible fully electronic systems for the control of sig-nals,
points and other safety measures along the track.
Communication Media:-
The communication links making up the data network may be over a combination
of any of the following media :
OFC,
Digital MW,
IP Radio links,
VSAT, Analog MW,
Twisted pair copper, for last mile connectivity.

35. 35
Wherever feasible wireless LAN (WiFi, WiMax) as per latest international
standards may also be adopted.
Railways Private Network is built up by utilising bandwidth from
Railways’ own Railtel Corporation of India (RCIL) or leasing bandwidth from
BSNL or other service providers.
Network Speeds: -
The earlier networks were non-IP based and worked at speeds of 9.6 Kbps.
Gradually some of the non-IP based network speeds were upgraded to 64 Kbps.
Generally higher speeds are not adopted in non-IP networks.
Presently networks are mostly IP based and operate at speeds of 2 Mbps
at the core and distribution levels and 64 kbps at the access level.
Speeds of n x 64 Kbps may be used at important access points depending on
the network traffic.
Similarly at the core level n x 2 Mbps may also be adopted.
In a centralized system as in FOIS, the core level comprises the communication
links between CRIS (Centre for Railway Information System)/ Rly.Board and
zonal Hqrs.
Distribution level comprises the communication links between zonal Hqrs. and
divisions and access level is made up of links connecting the division to the
activity centres .
In a distributed system as in PRS, the computers at the 5 metro cities are
connected in a mesh topology and form the core network. The network connecting
the 5 locations to other zonal headquarters and divisional headquarters forms the
distribution layer and the connections from the zonal/divisional headquarters to
the other locations forms the access network.
Network Security:-
The main aspects of security is :
Data sent by the sender should be received only by the intended receiver. This is

36. 36
achieved through encryption at various levels. Encryption can be built in at application
level as well as network level. The various data encryption standards are IP sec. DES,
3 DES, AES, private/public key etc.
Optical fiber Telecommunication for Railway Utility
A modern telecommunication network for railway utility must be able to handle
the emerging of advanced remote control centres, digi tal telephone exchanges , train
radio systems and the extensive development of central and local data systems. T
herefore, it is recommended to apply digital PCM transmission equipment,
using optical fibers as transmission media.
The advantages of this kind of telecommunication networks are the
low establishing costs compared to its enormous capacity.
For ex., an 8 or 12 fiber cable is able to handle all to- day known railway
transmission requirements and even more. Furthermore, the transmission network
is immune to electromagnetic disturbances in connection with electric railway
traffic. In optical fiber telecommunication systems, primarily monomode fibers are
used today, providing an extremely high bandwidth (>300GHz x km) and a very low
attenuation (0.2 dB/km) .
We'll give a brief introduction to optical fibers here.
An optical fiber is a thin, flexible, transparent fiber that acts as a waveguide, or
“light pipe”, to transmit light between the two ends of the fiber.
Optical fibers are widely used in fiber-optic communications, which permits
transmission over longer distances and at higher (data rates) than other forms of
communication.
Fibers are used instead of metal wires because signals travel along them with less
loss and are also immune to electromagnetic interference. Fibers are also used for
illumination, and are wrapped in bundles so they can be used to carry images, thus
allowing viewing in tight spaces. Specially designed fibers are used for a variety
of other applications, including sensors and fiber lasers.

37. 37
The structure of a typical single-mode fiber .
1. Core: 8µm diameter
2. Cladding: 125µm dia.
3. Buffer: 250µm dia.
4. Jacket: 400µm dia.
Optical Fiber Communication Network at IR
IR Vision is to tap revenue generation potential in the telecom and IT sector, using the
64,000-km long 'right of way' for laying optic fibres, signalling towers and other
infrastructure assets that Indian Railways owns.
OFCs are laid down along the track .
This will be done in collaboration between the RailTel Corporation and private
sector companies in a transparent framework.
Use of OF Technology in IR
The advantages of using OFCs over conventional copper cables include:
i) free from EMI and RFI making it especially useful in electrified areas.
ii) supports low bit-error rate digital communication .
iii) very high traffic carrying capacity and hence potential for leasing
excess capacity to other users and providing other services.

38. 38
iv) negligible cross-talk between channels.
v) insufficient commercial value of bits of cable and hence less prone to theft.
vi) multiple joints does not significantly degrade BER and therefore speech
quality.
IR have commissioned their first optical fiber communication system, in the
busy suburban area of Mumbai over a distance of 60 km connecting 30 suburban
stations during 1989.
This was followed by installation of another 900 km fiber in connection with
railway electrification projects .
JOINTING AND TERMINATION OF OPTIC FIBRE CABLE
Techniques for jointing of optic fibre cable:-
(a) Mechanical Splice
This align the axis of the two fibres to be joined and physically hold them together.
(b) Fusion Splicing
This is done by applying localized heating (i.e. by electric arc or flame) at
the interface between the butted, pre-aligned fibre end, causing them to soften and
fuse together.
Following steps are involved for jointing of the cable :-
Preparation of cable for jointing
Stripping/cutting the cable
Preparation of cable and joint closure for
splicing Stripping and cleaving of fibres
Sealing of joint closure and
Placing joint in pit