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MIDDLE EAST TECHNICAL UNIVERSITY
ELECTRICAL AND ELECTRONICS ENGINEERING
DEPARTMENT
EE 300 SUMMER PRACTISE REPORT
Student Name: Selim Brekci
Student ID: 1813831
SP Company Name: Trk Telekom
Company Division: Trk Telekom
Anadolu Merkez-IBlge Mdrl
Engineer: nder nderolu
SP Date: 18.08.2014-12.09.2014
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TABLE OF CONTENTS
1. INTRODUCTION............................................................................... 1
2. DESCRIPTION OF THE COMPANY................................................... 1
2.1. COMPANY NAME.1
2.2. COMPANY LOCATION...................................................................2
2.3. GENERAL DESCRIPTION OF THE COMPANY.2
3. ACCESS - OPERATIONS DEPARTMENT ...8
3.1 FIBER OPTICS CABLE TECHNOLOGY.8
3.2 FIBER OPTIC CABLE REPAIR13
4. ACCESS- PLANNING AND INVESTMENT DEPARTMENT.16
4.1 GEOGRAPHICAL INFORMATION SYSTEMS (GIS) PROGRAM 16
4.2 DEFINITIONS FOR GIS16
4.3 HOW TO DRAW PLANS WITH GIS.19
4.4 PRINCIPAL CABLE.20
4.5 LOCAL CABLE..22
4.6 MANHOLE.24
4.7 FEEDER.25
4.8 TRENCHING.26
4.9 FIELD CABINETS26
5. NETWORK SYSTEMS DEPARTMENT 28
5.1 DEFINITIONS..29
5.2 ADVANTAGES OF NETWORK..29
5.3 NETWORK TYPES..29
5.4 NETWORK TOPOLOGIES.30
5.5 UNITS OF NETWORK SYSTEMS..34
6. CONCLUSION.38
7. REFERENCES ..39
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1. INTRODUCTION
I have performed my summer practice in Turk Telekom Ankara 1. Blge Mdrl. This
department of the Turk Telekom is one of the biggest headships. I have chosen Turk Telekom
because I want to work in telecommunication area in professional life. Obviously Telekom
has always been major communication network in Turkey and suitable place in order to get
professional experience about telecommunication area. During that internship, I have
learned many things about electronics engineering and observed the facilities of the
company. I have worked in different departments in Telekom. In the first two week I worked
in Access Operation Management (Eriim Operasyon Mdrl). In the second week I
worked in Access Planning and Investment Department then in the last week I was in
Network Management Department. In these three different departments I have learned
many different working areas of Telekom and it was very beneficial for me because one of
my purposes is learning the working life. I wanted to learn the principles of communication.
We learn theoric information in university. I want to learn how I apply our theoric
information to practise. If I will begin to work in communication technologies area, I think
this summer practice will be useful for me. Moreover, I have worked alone until now and I
see now benefits of team work.
In this report I started with introducing company. Then I reported what I have performed
and learned during my summer practices. I have given detailed information about my
works. At this part I have used many figures and photographs in order to better explain my
works. After that, I summarized my report in Conclusion part. I included the sources of the
documents from which I took help in the References part.
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2. DESCRIPTION OF THE COMPANY
2.1. COMPANY NAME Trk Telekom Anadolu Merkez-1 Blge Mdrl
2.2. COMPANY LOCATION
Address: ANAFARTALAR MH. SANAY CD. SUSAM SK NO:14 PK:06104 ALTINDA
ANKARA
Phone: 03123121250
2.3. GENERAL DESCRIPTION OF THE COMPANY
Trk Telekom, Turkeys leading communications and convergence Technologies company,
offers integrated telecommunications services from fixed lines to GSM and to broadband
Internet. The Trk Telekom Group companies, as of June 30, 2014 have 13,4 million fixed
line, 7,4 million broadband (wholesale) and 15,8 million mobile subscribers. Group
companies with their nation-wide network infrastructure, provide their clients an extensive
set of services to their clients in Turkey; individuals and corporate. Trk Telekom, is 100%
shareholder of the companies; TTNET, the broadband operator in Turkey the convergence
Technologies company, Argela, the IT solutions provider Innova, Sebit Inc., an online training
materials company and AssisTT, a call center company. The company also holds 89.99% of
the shares of Avea that is one of the three GSM companies in Turkey. Moreover, Trk
Telekom through the Trk Telekom International Holding BV, which is by 100% belongs to
Trk Telekom, is also the 100% owner of Europes pioneering independent wholesale data
and capacity service provider Trk Telekom International AG AT and its affiliates. In addition,
it also holds indirect minority shares in the Albanian telecommunications operator
Abtelecom.
55% of the shares of Trk Telekom belong to the Ojer Telekomnikasyon A.. and 30% to the
Undersecretary of Treasury under the Prime Ministry of the Republic of Turkey. The
remaining 15% of the shares have been offered to public. The Trk Telekom shares, as of
May 2008 are traded at the BIST (Borsa Istanbul).
According to a study by Brand Finance, one of UKs leading brand valuation companies, Trk
Telekom has been awarded the title Turkeys Most Valuable Brand six consecutive times
between 2009 and 2014.
With a consolidated investment amount of more than 15 billion TRY since 2005, Trk
Telekom with the investments it carries out works to create value for the economy, its
clients and the societies it belongs to.
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2.4 ORGANIZATIONAL STRUCTURE:
Figure 1: Organizational Structure of Turk Telekom
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2.5 MISSION and VISION
Vision: To be the preferred communication operator of the future.
Mission: To provide fast, high quality and affordable services to our customers
anywhere and anytime by offering customer-focused integrated communication
solutions.
2.6 NUMBER OF EMPLOYEES
According to company regulations, we are not allowed to give detailed information
about this topic. However, by June 2014, it is reported that there are more than
34.000 employees, 3841 of which are engineers, working in Turk Telekom.
2.7 OWNERSHIP STRUCTURE
Figure 2: Ownership Structure of Turk Telekom
2.8 BRIEF HISTORY OF THE COMPANY
Trk Telekom has always been the major communication network in Turkey since
1840
1995 April 24th - By separating the telecommunication and Postal services in PTT
from each other, Trk Telekomnikasyon A.. was founded.
1999 June - The wireless telephony system (KTS), which provides wireless access to
local exchanges, was brought into service.
2000 - Cable Internet applications were started on Cable TV.
2004 February 19th - TT&TIM Communication Services Inc., establihed by the
merger of Turk Telekoms GSM Operator Aycell and -TM, was officially founded.
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October 15th - The commercial name of TT&TIM Iletisim Hizmetleri A.S. was
changed as Avea Iletisim Hizmetleri A.S.
July 22nd - Trksat A.. was established and started operating apart from Trk
Telekom.
2005 November 14th - Trk Telekoms privatization process was completed and
%55 shares of Turk Telekom was sold to Oger Telecoms Joint Venture Group.
2006 September 15th - Trk Telekom acquired -TMs 40.56% share in Avea for
USD 500 million and Turk Telekoms share in Avea increased to 81.12%.
2008 May 15th - The initial public offering for 15% of Turk Telekom shares was
completed and the shares started trading in the Istanbul Stock Exchange.
2009 July - Avea successfully started 3G services.
2010 June - An integrated multi-pass fiber optic network was installed between the
Middle East, Southern Asia and the Far East as a result of the JADI LINK project
signed on 16th June 2010, where the name derives from the initials of the
following cities; Jeddah (Saudi Arabia), Amman (Jordan), Damascus (Syria) and
Istanbul (Turkey).
2010 July - Trk Telekom acquired Invitel International (named as Turk Telekom
International AG AT after the acquisition), leading wholesale and data services
provider in the CEE region.
2011 July - Trk Telekom is the first telecommunications company of Turkey to
report to CDP (Carbon Disclosure Project) its carbon emission.
2011 August - Trk Telekom Mobile service in Germany is provided through Trk
Telekomnikasyon Euro GmbH company which is wholly-owned subsidiary of Trk
Telekom.
2012 March - Isbank Group Companies, owning 18.63% shares of Trk Telekom
subsidiary, Avea, chose not to exercise their preemptive rights while Trk Telekom
exercised its unexercised rights as well as its own rights, resulting in Trk Telekom's
ownership in Avea increasing to 89.99% on March 30, 2012.
2013 November - Trk Telekom signed a strategic partnership with USA based
Akamai with the aim of optimizing the network efficiency of Turkey's Internet
infrastructure. The partnership was announced at a press conference in London.
2014 May - Trk Telekom and Orange Business Services sign a giant cooperation.
With the 'Trk Telekom Global Kurumsal A' (the Trk Telekom Global Corporate
Network), which is the fruit of the signed agreement, Turkish companies will be
able to manage their communications with anywhere in the world, easily and
safely, with the comfort of their own HQ in Turkey.
2014 July - The international credit rating corporation Standard&Poors (S&P)
increased Trk Telekom's rating to BBB-; investment grade, underlining the 1 bn $
worth of successful bond exports of June 2014 that improved the company's
liquidity position.
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3. ACCESS-OPERATIONS DEPARTMENT
During the first two weeks of my internship, I have been in Turk Telekom Operations
department. I have worked in the fiber optics cable area, working principles of fiber optics
cables, kinds of fiber cables and repair of ruptured fiber cables. During this part of my
internship many times I have gone with technicians to repair of broken fiber optics cable.
With the help of engineers and technicians I have learned repair of cables own my own. It
was very useful to understand fiber optics cable technology and its usage areas.
3.1 FIBER-OPTICS CABLE TECHNOLOGY
An optical fiber cable is a cable containing one or more optical fibers that are used to carry
light. The optical fiber elements are typically individually coated with plastic layers and
contained in a protective tube suitable for the environment where the cable will be
deployed. Different types of cable are used for different applications, for example long
distance telecommunication, or providing a high-speed data connection between different
parts of a building.
Figure 3: Inner structure of multi tube optical fiber cable
DESIGN OF OPTICAL FBER CABLES
Optical fiber consists of a core and a cladding layer, selected for total internal
reflection due to the difference in the refractive index between the two. In practical
fibers, the cladding is usually coated with a layer of acrylate polymer or polyimide.
This coating protects the fiber from damage but does not contribute to its optical
waveguide properties. Individual coated fibers (or fibers formed into ribbons or
bundles) then have a tough resin buffer layer and/or core tube(s) extruded around
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them to form the cable core. Several layers of protective sheathing, depending on
the application, are added to form the cable. Rigid fiber assemblies sometimes put
light-absorbing ("dark") glass between the fibers, to prevent light that leaks out of
one fiber from entering another. This reduces cross-talk between the fibers, or
reduces flare in fiber bundle imaging applications.
CAPACITY AND MARKET OF OPTICAL FIBER CABLES
Modern fiber cables can contain up to a thousand fibers in a single cable, with
potential bandwidth in the terabytes per second. In some cases, only a small fraction
of the fibers in a cable may be actually "lit". Companies can lease or sell the unused
fiber to other providers who are looking for service in or through an area. Companies
may "overbuild" their networks for the specific purpose of having a large network of
dark fiber for sale, reducing the overall need for trenching and municipal permitting.
RELIABILTY AND QUALITY
Optical fibers are very strong, but the strength is drastically reduced by unavoidable
microscopic surface flaws inherent in the manufacturing process. The initial fiber
strength, as well as its change with time, must be considered relative to the stress
imposed on the fiber during handling, cabling, and installation for a given set of
environmental conditions. There are three basic scenarios that can lead to strength
degradation and failure by inducing flaw growth: dynamic fatigue, static fatigues, and
zero-stress aging.
FIBER MATERIAL OF CABLES
There are two main types of material used for optical fibers. These are glass and
plastic. They offer widely different characteristics and therefore fibers made from the
two different substances find uses in very different applications.
PROPAGATION SPEED AND DELAY
Optical cables transfer data at the speed of light in glass (slower than vacuum). This is
typically around 180,000 to 200,000 km/s, resulting in 5.0 to 5.5 microseconds of
latency per km. Thus the round-trip delay time for 1000 km is around 11 milliseconds
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JACKET MATERIAL OF OPTICAL FIBER CABLE
The jacket material is application specific. The material determines the mechanical
robustness, aging due to UV radiation, oil resistance, etc. Nowadays PVC is being
replaced by halogen free alternatives, mainly driven by more stringent regulations.
Material Halogen-
free UV Resistance Remark
LSFH Polymer Yes Good Good for indoor use
Polyvinyl chloride (PVC) No Good Being replaced by LSFH
Polymer
Polyethylene (PE) Yes Poor Good for outdoor applications
Polyurethane (PUR) Yes Fair Highly flexible cables
Polybutylene
terephthalate (PBT) Yes Fair Good for indoor use
Polyamide (PA) Yes Good-Poor Indoor and outdoor use
Figure 4: Jacket Material Properties of fiber optic cables
SAFETY REQUIREMETS
Because the infrared light used in communications cannot be seen, there is a
potential laser safety hazard to technicians. In some cases the power levels are high
enough to damage eyes, particularly when lenses or microscopes are used to inspect
fibers which are inadvertently emitting invisible IR. Inspection microscopes with
optical safety filters are available to guard against this.
Small glass fragments can also be a problem if they get under someone's skin, so care
is needed to ensure that fragments produced when cleaving fiber are properly
collected and disposed of appropriately.
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COLOUR CODES OF PATCH CORDS
The buffer or jacket on patch cords is often color-coded to indicate the type of fiber
used. The strain relief "boot" that protects the fiber from bending at a connector is
color-coded to indicate the type of connection. Connectors with a plastic shell
typically use a color-coded shell. Standard color codes for jackets and boots are
shown below:
Buffer/jacket
color Meaning
Orange multi-mode optical fiber
Aqua OM3 or OM4 10 gig laser-optimized 50/125 micrometer
multi-mode optical fiber
Violet OM4 multi-mode optical fiber (some vendors)
Grey outdated color code for multi-mode optical fiber
Yellow single-mode optical fiber
Blue Sometimes used to designate polarization-maintaining
optical fiber
Figure 5: Jacket material color codes of fiber optic cables
LOSSES IN FIBER OPTIC CABLES
Typical modern multimode graded-index fibers have 3 dB/km of attenuation loss at
850 nm and 1 dB/km at 1300 nm. 9/125 singlemode loses 0.4/0.25 dB/km at
1310/1550 nm. POF (plastic optical fiber) loses much more: 1 dB/m at 650 nm. Plastic
optical fiber is large core (about 1mm) fiber suitable only for short, low speed
networks such as within cars.
Each connection made adds about 0.6 dB of average loss, and each joint (splice) adds
about 0.1 dB. Depending on the transmitter power and the sensitivity of the receiver,
if the total loss is too large the link will not function reliably.
Invisible IR light is used in commercial glass fiber communications because it has
lower attenuation in such materials than visible light. However, the glass fibers will
transmit visible light somewhat, which is convenient for simple testing of the fibers
without requiring expensive equipment. Splices can be inspected visually, and
adjusted for minimal light leakage at the joint, which maximizes light transmission
between the ends of the fibers being joined.
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MULTI-FIBER CABLES COLOR CODES
Individual fibers in a multi-fiber cable are often distinguished from one another by
color-coded jackets or buffers on each fiber. The identification scheme used
by Corning Cable Systems is based on EIA/TIA-598, "Optical Fiber Cable Color
Coding." EIA/TIA-598 defines identification schemes for fibers, buffered fibers, fiber
units, and groups of fiber units within outside plant and premises optical fiber cables.
This standard allows for fiber units to be identified by means of a printed legend. This
method can be used for identification of fiber ribbons and fiber subunits. The legend
will contain a corresponding printed numerical position number and/or color for use
in identification.
Figure 6: Color codes of multi fiber cables
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3.2 FIBER OPTIC CABLE REPAIR
During the first two weeks of my internship I have gone with Telekom fiber optical cable
repair team to fix broken fiber cables. I took an active role in repair works. Engineers taught
me about understanding repair plans, identifying color codes of fiber optical cables and
using fiber cable repairing kit. There are many reasons that why optical fiber cables are
broken even though they are in underground and they have durable jacket materials. The
reasons of broken cables are listed below:
The most common cause of fiber cuts come from construction companies and
excavators that dont call before they dig.
Rats which are gnawing underground cables.
Weather conditions for example big storms cause to breaking off submarine cables.
Theft and vandalism are other reasons of broken fiber optical cables. The expensive
cost of the fiber cables makes them target of thief.
INSTRUCTIONS FOR REPAIR OF FIBER OPTIC CABLE
1) Strip the outer jacket away with a cable stripper. Rotate the tool around the cable one
time, and then turn the blade 90 degrees. Pull the stripper along the cable to slit along its
length. You can then peel the jacket off to reveal several protective layers that must be
removed in turn using scissors or a hobby knife. Under the protective layers are bundles
of fibers, which look much like wires. Remove the inner jackets and wipe away the
protective gel with a pad soaked in alcohol.
2) Clean the fiber optic stripper with alcohol. Remove the buffer tube with the stripper and
clean the fiber until it squeaks. Examine it under magnification to see that you have
removed all of the buffer tube. Insert the fiber in the cleaving device, lock it in place and
cut it to length. Cleavers don't actually cut the fiber. They put a small nick in it and break
it along a precise angle. Cleavers used for fusion splices operate at closer tolerances than
those meant for mechanical splices and consequently cost more.
3) Insert the fiber in the mechanical splice alignment tray. Some have covers that snap in
place after the fiber is installed. Others are meant to have the fiber slide in from the end.
Follow the manufacturer's instructions. These devices have gel that helps to reduce
losses. One type of mechanical splice uses a window to allow the technician to align the
fiber physically in conjunction with a visible laser source.
4) Install new heat-shrink tubing before cleaving if using a fusion process. This step helps
prevent contamination. Just slide it off to one side until the fiber is joined. Open the
fusing device and align the fibers. Note that there are different channels for different
sizes. Close the tool and activate the electric arc to fuse the two ends together. One type
of tool both checks the new joint for losses and performs a tensile strength test as the
unit is opened. Slide the heat-shrink tubing over the new joint and shrink it to fit.
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MATERIALS AND MACHINES WHICH ARE USED IN REPAIR PROCESS
1) Fusion Splicer Machine
Figure 7: Fusion Splicer Machine
o In Turk Telekom we have used the machine which is shown in the figure-7 as a tool of
fusion splicing. Current fusion splicers are either core or cladding alignment. Using
one of these methods the two cleaved fibers are automatically aligned by the fusion
splicer in the x,y,z plane, then are fused together. Prior to removing the spliced fiber
from the fusion splicer, a proof-test performed to ensure that the splice is strong
enough to survive handling, packaging and extended use. The bare fiber area is
protected either by recoating or with a splice protector. A splice protector is a heat
shrinkable tube with a strength membrane.
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2) Fiber Optic Splice Cassettes
Figure-8 : Fiber optic splice cassettes
o A splice cassette (also known as splice distributor) is a housing in which fiber optic
cables begin or end. Fiber optics are fanned out in splice boxes that are situated at
the end of fiber optic transmission paths.
The main components of a splice box are the splice cassette that picks up the fibers
and their reserves, and the front panel which contains different connectors for
transmitting signals via copper or fiber optic cables. The splice cassette is removable
in order to assemble fiber optics with a splice unit. The front panel can also be
removed to splice the fibers to various connectors.
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4 ACCESS PLANNING AND INVESTMENT DEPARTMENT
During the second week of my internship, I have been in Turk Telekom Access planning
department. I have mainly worked on the computer program which is called Geographical
Information Systems (GIS). During this part of my internship many times I have worked with
engineers to make plans on GIS. With the help of engineers I have learned usage of this
program and importance of planning department in Turk Telekom in terms of infrastructure
services. It was very useful to understand Geographical Information System and its usage
areas.
4.1.GEOGRAPHICAL INFORMATION SYSTEMS (GIS)
Actually, geographical information system application is used in whole world. Such as United
States, France, England, Canada and many other countries. In Turkey, Turk Telekom invested
around 5 million dollars to develop and adaptation for Turkey. Many public services work
thanks to geographical information system programme such as police, fire-fighting,
emergency services and national address database. This system is developed with Google
Earth mapping programme. Especially in Turkey we can say that this programme is more
actual and usable than Google Earth.
In this part of my internship report I will introduce some definitions which are used in Turk
Telekom planning department and geographical information systems programme.
4.2. DEFINITIONS
LOCAL STATION: Local phone stations which is connected with subscribers via access
network.
TOLL: A device that receives calls and allows them to be transmitted to the next local
calling area, thus avoiding toll or access charges.
R/L : A transmission system which is used for transferring sound, image and data
signals from one point to another point via electromagnetic waves.
COPPER JUNCTION : A transmission medium that carries sound, image and data
signals via copper wires.
F/O : A transmission type that carries electrical signals in optical-fiber materials.
DAMA (Demand Assigned Multiple Access): is a technology used to assign
a channel to clients that don't need to use it constantly. DAMA systems assign
communication channels based on requests issued from user terminals to a network
control system.
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PORT : A signal capacity unit which has 30 channel.
DISTRIBUTION FRAME : is a passive device which terminates cables, allowing
arbitrary interconnections to be made. For example, the Main Distribution
Frame (MDF) located at a telephone central office terminates the cables leading
to subscribers on the one hand, and cables leading to active equipment (such
as DSLAMs and telephone switches) on the other.
COAXIAL CABLE : is a type of cable that has an inner conductor surrounded by a
tubular insulating layer, surrounded by a tubular conducting shield. In
telecommunication coaxial cable is used in transporting of sound, image and data
signals
JUNCTION CABLE : Cables which are used for interconnection between centrals.
PRINCIPAL CABLE : Fiber or copper cable which is established between central and
field cabinet.
FIELD CABINET : A cabinet which is used to connect copper wires and principal cables.
LOCAL : A copper wire between field cabinet and client cabinet.
PAIR GAIN SYSTEM : is a method of transmitting multiple signals over the twisted
pairs traditionally used for a single traditional subscriber line in telephone systems..
BASE STATION : is a fixed communications location and is part of a networks wireless
telephone system. It relays information to and from a transmitting/receiving unit,
such as a mobile phone.
CABLE MANHOLE : An access hole that allows entry of service personnel into a small
room which has cables.
FEEDER CABLE : Feeder cables are one of several large cables that provide a physical
connection between a central office and distribution cables that connect to end
customers. Feeder cable usually is placed in underground conduit
INTERNAL CABLE (ANKASTRE) : Phone cables from cabinet which is in building door
to the resident.
FIBER TERMINATION DEVICE : A device which is used for converting optical signals to
electrical signals.
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4.3 HOW TO DRAW PLANS WITH GEOGRAPHICAL INFORMATION SYSTEMS
4.3.1 - SPOT MODULE
Figure-9 Module of geographical information systems application
Spot plans are plans which involve all buildings and their necessary information of the land.
Spot plans keep all this information via using symbols, definitions, and marks. On the spot
plans;
- Central borders
- Door numbers and names of buildings
- Location, name and number of buildings such as home, flat, office, banks, and schools
- Name of streets, boulevards and roads.
- Land and parcel numbers
- Embedded (Ankastre) places
- Distribution boxes and their places.
- Locations, numbers, capacities and borders of cabinets
- Upper structure plants
- Turk Telekoms buildings and lands
- Letterhead information.
All of the information above kept in the Turk Telekom geographical information system spot
module. Spot module enable to us many facilities such as digitise all buildings in working
central area, addressing via middle and border lines of roads, keeping information about
city-blocks, parcels, quarters and municipalities. .
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In the figure-9 tools of spot module are shown. These symbols make operations which are
shown in figure-10 below.
- Add building
- Divide building
- Unite building
- Add entrance
- Edge of road
- Important place
- Important field
- Draw housing estate
- Draw embedded
- Embedded panel
- Payphone
- Move building
Figure-10 Spot Module Operation buttons in GIS
4.3.2 UNDERGROUND MODULE
Underground plans should contain information below;
- Road and street names
- Locations and borders of telephone centrals
- Block and layout conditions
- Door numbers of buildings
- Lands and buildings which belongs to Turk Telekom
- Manhole and hand hole types and places
- Distance between manholes
- Total mesh numbers and types of underground cable system
- Details of meshes
-Information about which cable passes through which mesh
- Cabinet's location, type, capacity and borders
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In the figure-9 tools of underground module are shown. These symbols make operations
which are shown in figure-11 below.
- Manhole
- Draw with distance
- Feeder
- Trenching
- Pole
- Carry flag
- Assign cable to mesh
Figure-11 Underground Module
4.4 PRINCIPAL CABLE
Principal wire is a multi-per underground cable between distribution frame and field cabinet.
Generally principal cables contain 1800 and more per.
Principal cables are high capacity cables which contain circular positioned hundred cable
modules. They connect subscriber and distribution frame. After the distribution frame if
necessary they split into small capacity cables such as 1200, 900, 600, 300 per cables.
According to their design principal cables take different letter codes like A, B, C, D AA, AB,
AC..
Name giving to cables is a very important issue and during the planning designer should be
very careful about this. Since after the distribution frame thousands of cable may lay and
they can easily get confused.
For principal cable drawing firstly, we choose principal cable module from the controller
part. After this choosing we can also see present principal cables on the planning line.
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Figure-12 Principal cable drawing module
From this module we choose draw cable part and then we can understand the activation of
drawing tool by bubble on the mouse mark on the screen. Starting from the telephone
central building we click for once on the left button on the mouse and follow the cable
route.
If we want to change direction of the cable click the left button on the mouse and then we
follow the new route from the bend point. Generally on the bend points there are cable joint
holes so we shall use double click on this point since double click means end of the cable and
we should enter the program the information of cable which has just plotted. As a program
facility every principal cable holds own decades and hundreds information and guide to draw
next cable. By this way it prevents possible mistakes while cable drawing. Thanks to GIS
program facilities while plotting plans entering and saving data at certain intervals is a
reasonable solution.
Figure-13 GIS Principal Cable Information
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After the process on the screw plate which is on the screen we will choose type of cable joint
according to principal cable type. If the type of the cable is named as PAP which is
underground cable and if it is named as AP that means overhead cable.
When cable type is selected, capacity information of cables becomes ready to choose.
Overhead cables have capacities between 100 and 400 whereas underground cables have
capacities from 600 to 1800.
After than we marked the drawn cable contains which cable and which hundreds are active
or passive on the information screen. After all of these processes our cable is ready to lay for
planned route.
4.5 LOCAL CABLE
Local cable is used in between field cabinet and
subscriber distribution box. Their capacities and per
numbers are less than principal cables capacities.
Figure-14 miscellaneous local cables
LOCAL CABLE TYPES
(KPD-AP-A)
These types of cables are used in country side and out of the cities. For short distances,
cables with 0.4 and 0.5 mm. diameters are used. However for long distances cables with 0.6
and 0.9 mm. diameter are used. While local cable which has 0.4 and 0.5 mm diameter
contains 200 per, otherwise cable which has 0.6 or 0.9 diameter contains 100 per capacity.
Figure-15 Overhead type telephone cable (KPD-AP-A)
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Properties of KPD-AP-A
Solid electrolytic copper conductor
Lathery PE isolation
Moisture retarder non-conductor polyester jacket
Aluminium foil coating
Black poly-ethylene cable splice closure
(KPD-PAP)
These are cables which are mainly used in underground soil
pipes. While KPD-PAP cable which has 0.4 and 0.5 mm
diameter contains 400 per, otherwise cable which has 0.6 or
0.9 diameter contains 200 per capacity. Figure-16 KPD-PAP
Properties
Solid electrolytic copper conductor
Lathery PE isolation
Moisture retarder non-conductor polyester jacket
Aluminium foil coating
Medium density black poly-ethylene cable overlay
Figure-17 Acronyms for cables
K Spumescent (Kpkl)
D Quad (Drtl)
F Black-fill material
A Aluminium foil
P Poly-ethylene
A Overhead (ask telli-havai)
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4.6 MANHOLES
A manhole (alternatively utility hole, cable chamber, maintenance hole, inspection
chamber, access chamber or confined space) is the top opening to an underground utility
vault used to house an access point for making connections or performing maintenance on
underground and buried public utility and other services
including sewers, telephone, electricity, storm drains and gas.
Figure-18 Manhole on the road Figure 19 Turk Telekom manhole covers
Manhole Types
A manhole: A man hole with the only one cable entrance and one exit. This type of
manhole is used for along the street.
T Manhole: Its shape like a T this is the reason why we call it T type. There is one
entrance trenching and two exit trenching.
X Manhole: X type of manhole generally used in junctions there are a lot of exit and
entrance in this manholes.
L Manhole: Its shape is like a L. There is 90 degree angle between entrance and exit
trenching.
Figure-20 Representation of manhole in GIS
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Figure-21 Information window of manhole in GIS
4.7 FEEDER
Feeder is a cable which lies between manhole and buildings. In between building and
manhole there is HDPE (high density poly ethylene) pipes for feeder cabling.
Figure-22 Feeder cables which are coming from hand hole (manhole) in GIS
Fider Balants
Lokal
Kablo
Prensibal
Kablo
099 Nolu Fz H Lokali
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4.8 TRENCHING
It is a route between two manholes. Trenching link
manholes and hand holes. There are many meshes in
trenching. In recent years, Super-online operator is
using Turk Telekoms infrastructure services so some
of meshes are used by Super-online, therefore mesh
numbers of Turk Telekom is decreasing. Because of
this decreasing Turk Telekom uses 3x2 meshes instead
of 9x9 meshes.
Figure-23 Trenching window in GIS
4.9 FIELD CABINETS
Field cabinet links principal cables and local cables. There are three types of cabinets which
are used by Turk Telekom such as normal cabinet, HAES and GPON.
HAES (Exterior Active Access System) works with electronic card system. These cards provide
both phone and ADSL services together. Optical fibre cables are
connected with HAES cabinets. In normal cabinets only copper
wires can be connected. GPON cabinets are advanced versions of
HAES cabinets. Principal network starts with distribution frame
(repartitr ats) and ends with field cabinets.
Figure-24 Field cabinet
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27
In local distribution networks there are mainly three
types of cabinets such as cabinet with capacity 600,
cabinet with capacity 1200 and with capacity 2400.
The one important issue is when the field cabinet is
planted there will be always some empty ports for new
subscribers.
In field cabinets there are 300 pairs of module cabinet
blocks. If cabinet capacity is 1200 which means that
there are 4 cabinet blocks in cabinet.
Figure-25 Field Cabinet
For after the cables which are terminated in cabinets, branch wires should not be used.
Instead of this, connectivity module should be used.
In geographical information system krone
module connections makes in this way;
According to direction of coming, cable comes
into the cabinet then cable is stripped and
connected to the crone. This connection is
made in groups which consist of ten cables.
Camper wires are connected to lower contacts
of crone module. In this connection we use Figure-26 Field Cabinet in GIS
crone knife.
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Figure-27 Field Cabinet information window in GIS
5) NETWORK DEPARTMENT
In the last week of my internship I have worked in Network Systems Configuration and
Operation Management. And my unit was Data Systems. During this part of my internship
many presentations was done by both engineers and interns. In these presentations mainly
we have learned about basic information of network, network types and terms, their
advantages and disadvantages. I will give information about Data Systems. But we should
know some basic things about Network Systems. So, firstly I want to mention about Network
System in Turk Telekom than I will mention about my unit (Data Systems).
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5.1 Definition of Network
A network is a series of points or nodes interconnected by communication paths.
5.2 Advantages of Network
We can order advantages of Network as follows;
Information Sharing
Centralized Management and Support
Corporate Work
Security
Saving
5.3 Network Types
5.3.1. Local Network (LAN: Local Area Network):
A local area network (LAN) is a group of computers (network) in a small area such as home,
office and school. It is faster than other types of Network. Many computers can be
connected to share information and Internet connections.
5.3.2. Campus Network (CAN: Campus Area Network, Corporate Area Network):
CAN is a computer network made up of an interconnection of local area networks (LANs)
within a limited geographical area.
5.3.3. Wide Area Network (WAN):
Two or more LANS connect each other by telephone lines, leased- lines (It belongs to one
person or one corporation) or similar ways.
5.3.4. Metropolitan Area Network (MAN):
We can think that one city or one region merges with two separate LAN.
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30
5.4 Network Topologies
Topology is physical or logical structure of line. Network Topologies are divided two parts as
physical and logical topology.
Important Physical Topologies
5.4.1 Bus Topology:
A bus network is a network topology in which nodes are
connected in a daisy chain by a linear sequence of buses. The
bus is the data link in a bus network. The bus can only
transmit data in one direction, and if any network segment is
severed, all network transmission ceases. In a bus network,
every station receives all network traffic, and the traffic
generated by each station has equal transmission priority. Bus
Topology of a network is demonstrated in figure-28.
Figure 28: Bus Topology
Advantages of Bus Topology
Easy to connect a computer or peripheral to a linear bus.
Requires less cable length than a star topology.
It works well for small networks.
Disadvantages of Bus Topology
Entire network shuts down if there is a break in the main cable.
Difficult to identify the problem if the entire network shuts down.
It is slow when more devices are added into the network.
If a main cable is damaged then network will fail or be split into two networks.
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31
5.4.2 Ring Topology:
A ring network is a network topology in which each node connects to exactly two other
nodes, forming a single continuous pathway for signals through each node in ring. Data
travel from node to node, each node has equal transmission priority. Ring Topology is shown
in Figure 29.
Figure 29: Ring Topology
Advantages
Performs better than a bus topology under heavy network load.
Does not require a central node to manage the connectivity between the computers.
Due to the point to point line configuration of devices with a device on either side (each
device is connected to its immediate neighbor), it is quite easy to install and reconfigure
since adding or removing a device requires moving just two connections.
Point to point line configuration makes it easy to identify and isolate faults.
Disadvantages
One malfunctioning workstation can create problems for the entire network. This can be
solved by using a dual ring or a switch that closes off the break.
Moving, adding and changing the devices can affect the network.
Communication delay is directly proportional to number of nodes in the network.
Bandwidth is shared on all links between devices.
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5.4.3 Star Topology:
Star networks are one of the most common computer network topologies. In its simplest
form, a star network consists of one central switch, hub or computer, which acts as a
conduit to transmit messages. This consists of a central node, to which all other nodes are
connected; this central node provides a common connection point for all nodes through a
hub. The failure of a transmission line linking any peripheral node to the central node will
result in the isolation of that peripheral node from all others, but the rest of the systems will
be unaffected. Star Topology is shown in Figure.
Figure 30: Star Topology
Advantages
Star topology prevents the passing of data packets through an excessive number of
nodes.
As the central hub is the bottleneck, increasing its capacity, or connecting additional
devices to it, increases the size of the network very easily.
Centralization also allows the inspection of traffic through the network. Easy to detect
faults and to remove parts.
No disruptions to the network when connecting or removing devices.
Disadvantages
Failure of the central hub renders the network inoperable.
According to Bus Topology, more cable is used in Star Topology.
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5.4.4 Mesh Topology:
A mesh network is a network topology in which each node (called a mesh node) relays data
for the network. All nodes cooperate in the distribution of data in the network. A mesh
network whose nodes are all connected to each other is a fully connected network .A fully
connected network is a communication network in which each of the nodes is connected to
each other. Fully connected wired networks have the advantages of security and reliability:
problems in a cable affect only the two nodes attached to it. However, in such networks, the
number of cables, and therefore the cost, goes up rapidly as the number of nodes increases.
Mesh Topology is shown in figure 31.
Figure 31: Mesh Topology
Advantages
It is used if users want connection which is continuous.
It provides high incidence of redundancy.
If two computers disconnect from each other, there will be many ways.
Disadvantages
It is expensive.
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5.4.5 Broadcast Topology:
Broadcasting refers to a method of transferring a message to all recipients simultaneously. It
is shown in Figure 32.
Figure 32: Broadcasting Topology
In Turk Telekom, Network Systems are divided into three units.
5.5 Units of Network Systems
5.5.1.a) Telephone Central Systems: This unit gives telephone services.
5.5.1.b) Transmission Systems : The unit is responsible for ways of transmission which
provide dataflow together systems that belong to Turk Telekom. It is divided into two parts.
Cabled Transmission
2. Wireless Transmission
5.5.1.c) Data systems:
This unit provides from point to another point access services. As follows, I will mention
point to point services.
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35
1. XDSL Services: XDSL is a general name of reformed system which gives high speed and
data services over available copper circuit substructure. We can say DSL (Digital Subscriber
Line) at the same time. Digital Subscriber is not a complete end to end solution but rather a
Physical layer transmission technology like dial-up. DSL connections are deployed in the last
mile of a local telephone network-the local loop.
Types of XDSL
.ADSL (Asymmetric Digital Subscriber Line): It provides high speed access and data from
available a-b (UTP) line.
UTP (Unshielded Twisted pair): The cables are typically made with copper wires.
.SDSL (Symmetric Digital Subscriber Line): Send data traffic and receive data traffic are in
same speed.
.HDSL (High bit-rate Digital Subscriber Line): It supports two-way data transfer up to
2.340Mbps speed
.G.SHDSL (Symmetric High-data-rate Digital Subscriber Line): Download speed and upload speed
are same. It provides symmetric band wide and safe access.
.VDSL (Very High Speed DSL): It provides very high speed data transmission over copper
lines. It is the latest technology. Thanks to a symmetric DSL Technology, higher than 20
Mbit/s bit rate is possible. However; with an asymmetric Technology, maximum 100 Mbit/s
bit rate can be possible.
The maximum available bit rate is achieved at a range of about 300 meters. Performance
degrades as the distance increases.
The connection is set up between a pair of modems on either end of a copper wire that is
between the customer premises equipment and the Digital Subscriber Line Access
Multiplexer. All XDSL Services is given by DSLAM (Digital Subscriber Line Access Multiplexer).
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36
DSLAM is the device located at the providers central office and concentrates connections
from multiple DSL subscribers. Subscribers services are been by service cards. DSLAM is
shown in Figure 33.
Figure 33: Huawei DSLAM
2. ATM/TDM Service:
ATM (Asynchronous Transfer Model): ATM was created for time-sensitive traffic, providing
simultaneous transmission of voice, video, and data. ATM uses cells that are a fixed 53 bytes
long instead of packets. ATM is a standard multiplexing and switching technique. ATM
provides functionality that is similar to both circuit switching and packet switching networks.
By means of Circuit switching, cells are carried for correcting errors in a short time. Packet
switching provides decrease in time lag which originates in network topology. This process is
made by using multiplexing method in one physical line. ATM uses asynchronous time-
division multiplexing, and encodes data into small, fixed-sized packets (ISO-OSI frames)
called cells.
Control Card
PowerI
nput Service Cards
kartlar
Abone
ablolar
Subscriber
Cables
Cable
Rack
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37
TDM (Time DevisionMultiplexing):
TDM provides lease-lines to users. TDM Lease-line is a service which provides numerical,
continuous and constant bandwidth between two local points for Turk Telekoms corporate
customers. In other words it makes up data transfer configuration that reaches from point A
to point B. (For example; A is Ankara and B is Tokat).This configuration only enables
communication between these two points and it is closed to outside world. The most
important reason is preferred by customers is safe because TDM allocates special channel to
customers. Especially, if users want to transmit sound and video at the same time, they can
use lease-line. Lease-line provides the best solution. It is used for Internet access and
Connections between Offices
3. MPLS (Multiprotocol Label Switching) Service:
MPL-Sis a mechanism in high-performance telecommunications networks that directs data
from one network node to the next based on short path labels rather than long network
addresses, avoiding complex lookups in a routing table. MPLS is data-carrying mechanism
that emulates some properties of a circuit-switched network over a packet-switched
network. MPLS is a switching mechanism that imposes labels (numbers) to packets and then
uses those labels to forward packets. The labels are assigned on the edge of the MPLS of the
network, and forwarding inside the MPLS network is done solely based on labels. Labels
usually correspond to a path to layer 3 destination addresses (equal to IP destination-based
routing).In larger networks ,the result of MPLS labeling is that only the edge routers perform
a routing lookup. All the core routers forward packets based on the labels, which makes
forwarding the packets through the service provider network faster. (Most companies are
replacing their Frame relay networks with MPLS today). MPLS supports a range of access
technologies, including ATM, Frame Relay, and DSL.
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38
6- CONCLUSION
When I learned that I would do my summer internship in Turk Telekom Ankara, I was
appreciated to be a part of Telekom although it was true for a temporary time. Because I
have heard that Turk Telekom is biggest company for the electrical and electronic engineers
especially telecommunications engineers in Turkey.
In fact when I was doing my internship, I saw that it was true. It has really high standard in
telecommunication technology. However in my opinion the reason why it is one of the big
companies in Turkey is the discipline in the company especially after the privatization.
Indeed all the employees pay really attention to their duty and all the works are done
professionally. In addition, during my internship I had a chance of observing many things
about business life. First of all, I have understood that a big effort is needed to be a
successful engineer. You should always expand your knowledge, in other words you should
improve yourself.
On the other hand, if I have talked about the benefits that I got, first of all during internship,
I had learned different departments of telecommunication area because I have worked in
three departments of Turk Telekom Ankara. In all of the departments I have try to be a
participant of all works. Even in one times I hurt my eye when pulling an optical fiber cable.
This was not an important accident but this taught me the importance of labor and worker
safety. When I become an engineer I will never forget this accident and I will try to do my
best about labor and worker safety.
Indeed it is good to know someone will benefit from your works. May be the best sentence
that will explain the benefits of summer practice are that in the summer practice you
understand that being a part of an important job is one of the best thing in human life.
Actually I can really recommend this location to all the students for business life.
Because this company is one step further from most companies in Turkey with its facilities,
technological opportunities, etc. And I believe it will continue to be one of the important
companies of Turkey.
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39
7. REFERENCES
http://searchnetworking.techtarget.com/definition/network
http://en.wikipedia.org/wiki/Campus_network
CCNA: Cisco Certified Network AssociateStudy Guide
http://en.wikipedia.org/wiki/Very-high-bit-rate_digital_subscriber_line
CCNA: Cisco Certified Network AssociateStudy Guide
CCNA: Cisco Certified Network AssociateStudy Guide
http://en.wikipedia.org/wiki/Asynchronous_Transfer_Mode
CCNA: Cisco Certified Network AssociateStudy Guide
http://en.wikipedia.org/wiki/Multiprotocol_Label_Switching
http://en.wikipedia.org/wiki/Ring_network
http://en.wikipedia.org/wiki/Ring_network
http://en.wikipedia.org/wiki/Star_network
http://en.wikipedia.org/wiki/Mesh_networking
http://en.wikipedia.org/wiki/Broadcasting_(networking)
http://www.telecomdictionary.com/index.asp
http://en.wikipedia.org/wiki/Optical_fiber
https://www.turktelekomakademi.com.tr
http://en.wikipedia.org/wiki/Networking_cables
http://www.gislounge.com/
http://www.gisplanning.com/
http://ocw.metu.edu.tr/course/view.php?id=127
4.3.1 - SPOT MODULEFigure-11 Underground Module4.4 PRINCIPAL CABLEIn the last week of my internship I have worked in Network Systems Configuration and Operation Management. And my unit was Data Systems. During this part of my internship many presentations was done by both engineers and interns. In these presentation...A network is a series of points or nodes interconnected by communication paths.5.2 Advantages of NetworkWe can order advantages of Network as follows; Information Sharing Centralized Management and Support Corporate Work Security Saving5.3 Network Types5.3.1. Local Network (LAN: Local Area Network):A local area network (LAN) is a group of computers (network) in a small area such as home, office and school. It is faster than other types of Network. Many computers can be connected to share information and Internet connections.5.3.2. Campus Network (CAN: Campus Area Network, Corporate Area Network):CAN is a computer network made up of an interconnection of local area networks (LANs) within a limited geographical area.5.3.3. Wide Area Network (WAN):Two or more LANS connect each other by telephone lines, leased- lines (It belongs to one person or one corporation) or similar ways.5.3.4. Metropolitan Area Network (MAN):We can think that one city or one region merges with two separate LAN.5.4 Network TopologiesTopology is physical or logical structure of line. Network Topologies are divided two parts as physical and logical topology. Important Physical Topologies5.4.1 Bus Topology:A bus network is a network topology in which nodes are connected in a daisy chain by a linear sequence of buses. The bus is the data link in a bus network. The bus can only transmit data in one direction, and if any network segment is severed, all net... Advantages of Bus Topology Disadvantages of Bus Topology
In Turk Telekom, Network Systems are divided into three units.5.5 Units of Network Systems5.5.1.a) Telephone Central Systems: This unit gives telephone services.5.5.1.b) Transmission Systems : The unit is responsible for ways of transmission which provide dataflow together systems that belong to Turk Telekom. It is divided into two parts. Cabled Transmission 2. Wireless Transmission5.5.1.c) Data systems:This unit provides from point to another point access services. As follows, I will mention point to point services.1. XDSL Services: XDSL is a general name of reformed system which gives high speed and data services over available copper circuit substructure. We can say DSL (Digital Subscriber Line) at the same time. Digital Subscriber is not a complete end to end... Types of XDSL.ADSL (Asymmetric Digital Subscriber Line): It provides high speed access and data from available a-b (UTP) line.UTP (Unshielded Twisted pair): The cables are typically made with copper wires..SDSL (Symmetric Digital Subscriber Line): Send data traffic and receive data traffic are in same speed..HDSL (High bit-rate Digital Subscriber Line): It supports two-way data transfer up to 2.340Mbps speed.G.SHDSL (Symmetric High-data-rate Digital Subscriber Line): Download speed and upload speed are same. It provides symmetric band wide and safe access..VDSL (Very High Speed DSL): It provides very high speed data transmission over copper lines. It is the latest technology. Thanks to a symmetric DSL Technology, higher than 20 Mbit/s bit rate is possible. However; with an asymmetric Technology, maximu...The maximum available bit rate is achieved at a range of about 300 meters. Performance degrades as the distance increases.The connection is set up between a pair of modems on either end of a copper wire that is between the customer premises equipment and the Digital Subscriber Line Access Multiplexer. All XDSL Services is given by DSLAM (Digital Subscriber Line Access Mu...Figure 33: Huawei DSLAMTDM (Time DevisionMultiplexing):TDM provides lease-lines to users. TDM Lease-line is a service which provides numerical, continuous and constant bandwidth between two local points for Turk Telekoms corporate customers. In other words it makes up data transfer configuration that rea...
