Internship report on ethio telecom,@NAAZ

iIInternship Report 2019
Prepared By: Abdi Kissi i
Declaration
I am Abdi Kissi, a 5th year electrical and electronics engineering student that I have undertake
my internship experience in ethio telecom (hosting company) for a period of August 1/08/2019
to October 30/10/2019 G.C under the guidance of Dr. Muluneh Makonnen (Academic advisor)
and MR. Zerihun Bade (company advisor).
I clarify that my work is original and compiled according to the internship report writing
guideline given by the department. as the student academic advisor, I clarify that the internship
report prepared by Abdi Kissi is original work and compiled according to the guideline
provided by the department as far as my knowledge is concerned.
Intern: Abdi Kissi
Sign ____________________
Advisor: Dr.Muluneh Makonnen
Sign______________________

Prepared By: Abdi Kissi ii
Acknowledgment
Above all we would like to thanks great fully our God, the almighty, and the merciful. Without
his blessing and endorsement this internship program and project would not have been
accomplished and then we would like to thanks our family for supporting us through this
program economically as well as ideally.
Next to this we would also like to express sincere gratitude to our academic advisor Dr.
Muluneh for his supporting information and motivation for this internship report and we would
like to give a great regard and thanks to our department of Electrical and Computer Engineering
for providing this internship program to develop our practical knowledge and understanding
Lastly, we would also be very grateful to announce thanks to Ethio telecom giving us the
chance to perform our internship in their company. Also appreciate our supervisors Mr. Zerihun
Bade, Mr. Tekabe Kidane and Mr. Chala Urga for their direction, assistance, and guidance
during the time of internship. In addition, we would like to express our heart full gratitude to
all staff members in fixed access network section, for appreciating and give information about
the company and sharing their experiences. And also great thanks to our friends for giving good
ideas to support this internship report.

Prepared By: Abdi Kissi iii
List of Acronyms
ADSL Asymmetric Digital Subscriber Line
ALC Analog Line Card
APD Assist Planning and Development
CCC Cross Connection Cabinet
CE Central Exchange
CEO Chief Executive Officer
CPE Customer Premises Equipment
CDMA Code Division Multiple Access
DHCP Dynamic Host Configuration
DNS Domain Name Service
DSL Digital Subscriber Line
DSLAM Digital Subscriber Line Access Multiplexer
ETC Ethiopian Telecommunications Corporation
EPON Ethernet Passive Optical Network
EVDO Evolution Data Only or Evolution Data Optimized
EXCH Exchange
ETM Ethernet Transfer Mode
ETH Ethernet
FAN Fixed Access Network
FC Fluent Connect
GE2 Giga Ethernet 2
GILCA Giga Ethernet Integrate Line Card
GIS Giga Bit Control and Switch and Control Card
GPON Gigabit Passive Optical Network
GSM Global System for Mobiles
GOTA Global Open Trucking Architecture
IEEE International Electrical and Electronics Engineering
IP Internet Protocol

Prepared By: Abdi Kissi iv
ISP Internet Service Provider
ISDN Integrated Service Digital Network
Kbps Kilobits per second
LC Line Connector
MB Mega Byte
MDF Main Distribution Frame
MRP MSAG Packet Processing and Resource Card
MSAG Multi Service Access Gateway
NGN Next Generation Network
NACT Narrowband Active
NNOC National Network Operation Center
NAAZ North Addis Ababa Zone
NPR Network Project Rollout
OAD Optical Add and Drop
ODF Optical Distribution Frame.
OMD Optical Multiplex and Duplex
OLT Optical Line Terminal
OTDR Optical Time Domain Reflectometer
PMO Project Management Office
PRO Public Relation Officer
POST Plain Old Telephone Service
SC Subscriber Card
SFP Small Form Pluggable
RALC Reverse Analog Line Card
TSLC Test Subscriber Line Card
UIL University Industry Linkage
VOIP Voice Over Internet Protocol
WAN Wide Access Network
ZTE Zhong Xing Telecommunication Equipment Corporation

Prepared By: Abdi Kissi v
List of Figure
Figure 1. 1 Generalized ethio telecom customers................................................................... 4
Figure 1. 2 Main products in ethio telecom............................................................................ 5
Figure 1. 3 Organizational structure and work flow of Ethio telecom .................................... 9
Figure 2. 1 The oldest FAN topology ................................................................................. 11
Figure 2. 2 The latest topology for copper access network................................................... 11
Figure 2. 3 The latest topology for fiber access network...................................................... 12
Figure 2. 4 FAN division..................................................................................................... 12
Figure 2. 5 MSAG............................................................................................................... 14
Figure 2. 6Master shelf and Slave shelfs on MSAG............................................................. 15
Figure 2. 7Cards on MSAG................................................................................................. 16
Figure 2. 8 primary and secondary side of MSAG ............................................................... 19
Figure 2. 9Terminal............................................................................................................. 20
Figure 2. 10 ADSL.............................................................................................................. 20
Figure 2. 11Signal finder and tone generator ....................................................................... 22
Figure 2. 12 Insertion tool ................................................................................................... 22
Figure 2. 13Head set ........................................................................................................... 23
Figure 2. 14 UY connector .................................................................................................. 23
Figure 2. 15 ladder .............................................................................................................. 23
Figure 2. 16 ADSL splitter .................................................................................................. 23
Figure 2. 17 step one of ADSL configuration ...................................................................... 25
Figure 2. 18step two (a) of ADSL configuration.................................................................. 26
Figure 2. 19 step two (b) of ADSL configuration................................................................. 26
Figure 2. 20Step three of ADSL configuration .................................................................... 27
Figure 2. 21 Step four of ADSL configuration..................................................................... 28
Figure 2. 22Step five of ADSL configuration ...................................................................... 28
Figure 2. 23 Step six of ADSL configuration....................................................................... 29
Figure 2. 24 ADSL architecture........................................................................................... 30
Figure 2. 25Multi-mode and single-mode fiber.................................................................... 32

Prepared By: Abdi Kissi vi
Figure 2. 26 EPON.............................................................................................................. 33
Figure 2. 27OTDR .............................................................................................................. 33
Figure 2. 28Splicing Machine.............................................................................................. 34
Figure 2. 29Cutting machine/cleaver ................................................................................... 35
Figure 2. 30Protection Sleeve.............................................................................................. 35
Figure 2. 31 Optical Power Meter........................................................................................ 36
Figure 2. 32 Closure............................................................................................................ 36
Figure 2. 33Patch panel....................................................................................................... 38
Figure 2. 34 Patch Cord....................................................................................................... 39
Figure 2. 35Type of Transmission media............................................................................. 41
Figure 2. 36 Operating System of Transmission on MSAG ................................................. 41
Figure 2. 37 Transmission part of MSAG............................................................................ 42
Figure 2. 38optical power meter.......................................................................................... 43
Figure 2. 39Different type of attenuator............................................................................... 44

Prepared By: Abdi Kissi vii
List of Table
Table1. 1Color Code of Coppe............................................................................................ 30

Prepared By: Abdi Kissi viii
Table of Content
Declaration......................................................................................................................................... i
Acknowledgment ...............................................................................................................................ii
List of Acronyms.............................................................................................................................. iii
Table of Content..............................................................................................................................viii
Executive Summery .......................................................................................................................... x
CHAPTER ONE ............................................................................................................................... 1
INTRODUCTION............................................................................................................................. 1
1.1 Company Background and Overviews ......................................................................................... 1
1.2 Vision, Mission, Values and Objectives of The Company ............................................................ 2
1.3 The Main Customers or The End User ......................................................................................... 4
1.4 Main Products and Service........................................................................................................... 5
1.5 Stake Holder of Ethio telecom ..................................................................................................... 8
1.6 Organizational Structure and Work Flow of The Company .......................................................... 8
CHAPTER TWO ............................................................................................................................ 10
OVER ALL INTERNSHIP EXPERIENCE ..................................................................................... 10
2.1 The Objective of The Internship................................................................................................. 10
2.2. How I Get Into Company.......................................................................................................... 10
2.3. Fixed Access Network.............................................................................................................. 11
2.3.1 Copper Access Network.......................................................................................................... 13
2.3.2 Fiber Access Network............................................................................................................. 31
2.3.3 Transmission .......................................................................................................................... 40
2.4. Procedures I have been using while performing my work tasks ................................................. 44
2.5. My performance at the company............................................................................................... 44
2.6. Challenges I have been facing while performing my work tasks................................................ 45
2.7 Measuring or solution I have used for the challenges I have been facing..................................... 46
CHAPTER THREE......................................................................................................................... 47
OVERALL BENEFITS GAINED FROM THE INTERNSHIP........................................................ 47
3.1 Improving Practical Skills.......................................................................................................... 47
3.2 Upgrading Theoretical Knowledge............................................................................................. 48
3.3 In terms of Industrial Problem-Solving Capability...................................................................... 48
3.4 Interpersonal Communication Skill............................................................................................ 48
3.5. Improving our Team Playing Skill ............................................................................................ 49
3.6 Improving our Leadership Skill.................................................................................................. 50

Prepared By: Abdi Kissi ix
3.7 Understanding Work Ethics Related Issues ................................................................................ 50
3.8 In terms of Entrepreneurship Skills ............................................................................................ 51
CHAPTER FOUR........................................................................................................................... 52
CONCLUSION AND RECOMONDATION................................................................................... 52
4.1 Conclusion ................................................................................................................................ 52
4.2. Recommendation...................................................................................................................... 52
Reference........................................................................................................................................ 54

Prepared By: Abdi Kissi x
Executive Summery
The purpose of this report is to write a report about the internship experience that I have
undertaken, and to come up with what I have been working in three months’ internship stay at
our hosting company. The report is divided in to different parts starting from brief describing
the back ground of hosting company that is Ethio telecom, including its history, the main
products and services, customers or the end users and the overall organization and work flow
of the company briefly. while the other part is describe overall Technical Aspects of Internship
experience that I have gained during the practical time, including how I get into the company,
section of the company that I was working in and its work flow, I have visited the materials on
how to operate in the field and also observing the technician how to maintain each fault occurs
on the copper and fiber cable, as well as on MSAG box also I have seen partially transmission
part from operation and maintenance division(O&M). finally, this report includes the benefits
I have gained from the internship program in terms different perspectives skills such as
improving practical skills, entrepreneur ship skills, theoretical knowledge, inter personal
communication skills and understanding about work ethics related issues and finalized by
conclusion and recommendations for the company.

Prepared By: Abdi Kissi 1
CHAPTER ONE
INTRODUCTION
Globally, the development of telecommunication industry is one of the important indicators of
social and economic development a given country. In addition to this, the development of
communication sector plays a vital role in overall development of all sectors related to social,
political and economic affairs. This sector is very dynamic in its nature of innovation and
dissemination. Hence, it needs proper regulation like other critical economic sectors.
1.1 Company Background and Overviews
The introduction of telecommunication services in Ethiopia dates back to 1894, when Menelik
the second, the king of Ethiopia, introduces telephone technology to the country. The first long
distance link was made between Addis Ababa and Harar. In these early years, the new
technological scheme contributed to the integration of the Ethiopian society when the extensive
open wire line system was laid out linking the capital with all the important administrative
cities of the country. Most of the time communication network, however, it was completely
destroyed during the Italian Fascist aggression when later on Ethiopia had to start the
development of its telecommunication facilities all over again.
After the Adwa war resulting in Ethiopia victory an agreement was signed between the
Ethiopian government and Italian counterpart to establish 880km telephone line between the
Ethiopian capital city and Asmara. The project started in 1902 and was completed in
1905.Between 1905 and 1913 connections were established between Addis Ababa and Gondar,
southern and western Ethiopia (Gambella, Nekemte, Sidama, etc.). When the imperial
telecommunication Board of Ethiopia was established by proclamation 131/53 in 1953, it was
granted full provision of administrative and financial autonomy. The main objective of the
board was: To undertake the expansion of telecommunication services through the nation, to
allocate and control all communication frequencies etc. Just before the implementation of the
seventh Telecom development program (1998-2001) in the transitional year, several projects
and establishments have been executed to rehabilitate the network damaged by the 17th years
of war during the military Regime.

By the proclamation number 131/1952, a telecommunication entity, which exclusively regulate
and operate telecommunication services called Ethiopian Telecommunication Board(ETB)
established with affecting its function, the name ETB was later changed to Ethiopian
Telecommunication Authority(ETA).The ETA was working on an exclusive a basis operator
and regulator until the promulgation proclamation number 49/1996 that established a separate
federal telecommunication regulatory entity called Ethiopian Telecommunication Agency. On
November 1996, the ETA becomes ETC by council of Ministers regulation number
10/1996.The subsequent proclamation 49/1996 expands the duties and responsibilities. For its
international traffic links and communication services, ETC uses its earth station at sululta,
which transmits and receives to both Indian Ocean and Atlantic Ocean satellites. The ETC is
the sole telecommunication services provider in Ethiopia and it is the second largest state
owned company in Ethiopia, the largest being Ethiopian Air Lines.
In 2006 the ETC signed an agreement worth us $ 1.5 billion with three Chinese companies to
upgrade and expand Ethiopian telecommunication services. The three Chinese were ZTE
Corporation, Huawei Technologies and the Chinese International Telecommunication
Construction Corporation. This agreement was increased the number of mobile services from
1.5 million to 7 million, land line telephone services from one million to four million, an
expansion of fiber optics network, from 4,000km in 2006 to 10,000 by 2010. By 2011(2003
E.C) the Ethiopian government was made an agreement with France Telecom, one of the
world’s leader telecommunication companies. This Ethio Telecom was born from the ambition
of the Ethiopian government to provide a world-class telecom operator for the country.
Following these ambitions, the will of the government to be better serve Ethiopian citizens by
being a customer centric company.
1.2 Vision, Mission, Values and Objectives of The Company
Vision
➢ To be a world-class provider of telecommunications services in Ethiopia.
➢ To be committed to understand, meet and exceed the telecommunication needs and
expectations of country at large and customers in particular

➢ To be a center for advancement of ICT, via research, innovation, transfer, adoption,
diffusion, adaptation, integration and dissemination in Ethiopia in particular and in
East/Horn of Africa in general.
Mission
➢ Connect Ethiopia through state-of-the-art telecom services Provide high quality,
innovative and affordable telecom products and services that enhance the development
of our nation and ensure high customer satisfaction.
➢ Build reputable brand known for its customers‟ consideration.
➢ To connect every Ethiopian through ICT
➢ Build its managerial capability and manpower talent that enables Ethio telecom to
operate at international level.
➢ Support community and environmental development
Organizational values
➢ Lead with vision: Ethio telecom commits to understand, meet and exceed the
telecommunications needs and expectations of our country at large and of customers
in particular.
➢ Respect: Ethio telecom respects all customers and recognizes that their revenues allow
Ethio telecom to operate.
➢ Excellence: Ethio telecom will commit to high-level job performance, customer
service quality, organizational excellence and continuous improvement in all areas
Ethio telecom will make every effort to achieve a superior financial return.
➢ Lead with vision: Ethio telecom commits to understand, meet and exceed the
telecommunications needs and expectations of our country at large and of customers
in particular.
➢ Respect: Ethio telecom respects all customers and recognizes that their revenues allow
Ethio telecom to operate.

➢ Excellence: Ethio telecom will commit to high-level job performance, customer
service quality, organizational excellence and continuous improvement in all areas
Ethio telecom will make every effort to achieve a superior financial return.
➢ Integrity: Ethio telecom upholds ethical standards, being honest in all assignments.
➢ Accountability: Ethio telecom will hold us accountable to all our stakeholders.
Objective Of The Company
The main objective of Ethio telecom is to create awareness on products and services provided
by Ethio telecom and help citizens understand the subscription requirements.
The following are main objective of a company:
➢ Being customer-focused company.
➢ Offering the best quality of service
➢ Building a financial sound company.
➢ Meeting excellent world class standards.
➢ To provide products and services that enhances the development of our Nation.
➢ To build a successful brand known for its customer consideration.
1.3 The Main Customers or The End User
Generally, the customers of Ethio telecom are the entire people of Ethiopia where the
company’s network is covered. We can divide the customers of Ethio telecom in to two to make
its work clear and efficient. The two types of Ethio telecom customers are Enterprise customers
and Residential customers.
Figure 1. 1 Generalized ethio telecom customers

➢ The Residential Customers: - are those customers who are single users like us. For example,
any person that can use mobile network, fixed line network, fixed line telephone, internet
service are some of the residential customers.
➢ The Enterprise Customers: -are those customers like governmental organization, private
companies and nongovernmental organization. For example: banks, agricultural office,
health office, school, NGO etc.
1.4 Main Products and Service
Ethio Telecom is institutionalized with the objectives of promoting the development of high
quality, efficient, reliable and affordable telecommunication services in the country.
Its services can be broadly classified as:
Figure 1. 2 Main products in ethio telecom
I. Mobile service
➢ Mobile roaming: - is a service that helps subscribers automatically to make and receive
voice calls, send and receive data, or access other services when travelling outside the
geographical coverage area of Ethio Telecom, by means of using a visited country’s
operator’s network. It could be outbound roaming, a service given to Ethio customers who
wants to use their mobile phone abroad, and inbound, a service given to customers of
foreign operator who has a roaming agreement with it(like tourists, foreigner investors …).
Currently this service is provided only for GSM post paid subscribers.

➢ GOTA (Global Open Trucking Architecture):- is a service given using the CDMA2000
wireless network for the purpose of group communication. It allows two or more
individuals to communicate and also use for private and group calls using push to talk. The
service also allows the subscriber to make external calls after subscribing to the mobile
wireless service.
➢ Satellite Mobile Telephone: - is mobile phone that connects to orbiting satellites instead
of terrestrial network. It enables customers in every part of the globe to be beneficiaries of
telecom services through satellites stationed on the universe. Satellite phone is one of the
greatest innovations in communication. The satellite mobile telephone provides similar
features of communication services to that of earthly mobile telephones such as; voice,
SMS and low-band width internet access.[1]
➢ Business Mobile Service with/without CUG: - is a bundled postpaid mobile service that
allows enterprise customers to make calls at a discounted rate compared to the normal
mobile tariff rates.BM with CUG (Closed User Group) option, in addition to the business
mobile bundles, any calls out of the bundle made within the group are treated at a much
discounted rate. To subscribe CUG there should be at least five defined internal users
within the group for each organization. All services supported by GSM are also supported
by Business mobile.
➢ Vanity numbers: - are Mobile numbers which are memorable and easy to dial. Vanity
numbers are classified into four categories based on their easiness to remember. These
are Platinum numbers, Gold numbers, Silver numbers and Bronze numbers.
➢ Machine to Machine Service: -Machine to Machine is a wireless technology that enables
machines to talk to each other, and which customers can access directly from their office
or home computer
➢ Hybrid Business Mobile: -In the hybrid BM, customers will have postpaid bundle but
after the bundle it will be changed into prepaid mode automatically, so that Customer can
recharge whatever amount to use for out of bundle (OOB) usage and international calls.
➢ Packaged Services: - a service that could be provided in the form of voice off picks
package, GPRS package and SMS package. Special target of customers for all packages
include students, night shift workers, big Hotel workers and Taxi drivers.

II. Fixed line service
➢ It includes Wired Fixed line, Wireless Fixed line (CDMA), Short code, Bulk SMS and
ISDN/E1.
➢ Landline: -is a telephone line that travels over terrestrial circuits. A land line can be copper
wire, fiber optics or microwave.
➢ Wireless Fixed line: -is much similar to the ordinary fixed telephone service; it uses Fixed
Wireless Terminal (FWT) which enables it to give a voice, data and other value added
services. It works where ever CDMA network is available.
➢ ISDN/E1 service: -Integrated services digital network (ISDN) is an international
communications standard for sending voice, video, and data over digital telephone lines
or normal telephone wires.
II. Internet and data service
➢ Fixed wired broadband internet: -is provided through copper or fiber with different access
methods like ADSL, VDSL, EPON and GPON.
➢ Fixed wireless BB internet: -wireless is device or system used to connect different fixed
locations with a radio or other wireless link.
➢ Wireless broadband internet: -is an Internet service which can be given through
different access methods like, AIRONET, supports up to 54 Mbps downloading
capacity, VSAT (supports up to 2Mbps downloading capacity), 3G and EVDO.
➢ Evolution Data Only (EVDO) is a Broadband mobile Internet service with high speed
using CDMA technology. The service works wherever CDMA network is available.
The service is available in Addis Ababa and more than 200 cities and town throughout
the country. It is provided in three alternative packages: 1GB, 2GB and 4GB for both
prepaid and postpaid customers.
IV. Additional Business Services

➢ Virtual Private Network (VPN): - enables private and public institutions to connect
their various branches and to establish their own private networks. VPN enables you
to share information and activate all information technology systems inside your
branches via fixed and mobile options. The service is available all over Ethiopia in
areas covered by Ethio telecom terrestrial and mobile network that support data
services.[2]
➢ VSAT (Very Small Aperture Terminal): - is an internet or VPN service using a satellite
access mechanism. It is a way of establishing private satellite communication network
for large organizations that have widely dispersed locations.
➢ 4G Internet Access Technology: -is the 4thgeneration wireless internet access
technology that transforms the existing internet speed to a super-fast connection. The
users of 4G LTE network get the advantage of superior and un interrupted connectivity,
which enables to live stream, video and movies at much faster rate than ever before
and can also easily share information.
1.5 Stake Holder of Ethio telecom
Stakeholder is defined as those at groups without those supports the organization cease to exist.
Then it has gained wide acceptance in business practice and in theorizing relating to strategic
management, cooperate governance, business purpose and cooperate social responsibility
(CSR).
The stake holders of Ethio telecom are: - ZTE company, HUAWEI company, Ericsson
company, Customers and Government
1.6 Organizational Structure and Work Flow of The Company
Ethio Telecom organizational structure includes different functional divisions that are under
direct administration of Board of Directors. As the picture below shows the organizational
structure of Ethio telecom depends on functional structure. The company has six major
significant divisions, which is led by chief officer, departments led by officer and section led
by managers. Even if this is create divisional rivalries it is best suit the company for the easy
implementation of Enterprise solutions applications. [3] To grasp on our target divisions,
Residential division is responsible for the sales generated from residential people. Enterprise
division is responsible for all enterprises like government organization, profit and nonprofit

organizations. Marketing and communication division take care of marketing related activities
like tariff revision, new product or service launch and sales guides’ different sales analysis
including market research. Customer service divisions undertake after sales and presales
activities mainly994, 980 for VIP customers. Technical Division is the core division which is
responsible for entire network management of the company. Information system division
facilitates and ensures the automation part of the company as well as provides necessary
detailed and summarized information for managers depending on their request. [4]
Figure 1. 3 Organizational structure and work flow of Ethio telecom

CHAPTER TWO
OVER ALL INTERNSHIP EXPERIENCE
2.1 The Objective of The Internship
➢ To encourage the practical and theoretical knowledge through the practical work.
➢ To gain experience in design, implementation, and evaluation of worksite.
➢ Observe a corporate fitness center operation.
➢ Enhance written and verbal communication skills.
➢ Assist in program or product development.
➢ To attend one professional meeting.
2.2. How I Get Into Company
The new curriculum of Addis Ababa Science and Technology University for fast track students
states that, when the students finish 4th
year’s they should be sent to the company to
accomplished the internship program. The research and technology transfer office of our
university search internship place and transferred the list of 9 students from communication
stream to Ethio Telecom Company. First when we came to the company, they prepared the
welcome ceremony and give us half day induction training which deals over all organization,
work flow, product and services of the company presented by Ethio telecom staff member.
While finishing the training or orientation we are asked to choose one of the three departments
of Ethio-telecom. There are different departments in Ethio-telecom that are allowed for student
to practice during their internship for four months but for us they allow only three summer
months.
Three department are given as the choice those are:
➢ Fixed access network (FAN).
➢ Operation &Maintenance(O&M).
➢ Network Engineering.
From the above departments or sections I take experience on the FAN (Fixed Access network).
MR Zerihun Bade who was FAN training supervisor and assigned supervisor for us to start our
training around sadist-kilo or NAAZ FAN zone.

2.3. Fixed Access Network
Fixed Access Network is the part of telecommunications network which connects subscriber
to their immediate services provide through physical media either copper or fiber. It can
perform different task like Voice, Data, Internet, Fax and so on. Fiber is glass and copper are
metal. Copper is medium for electrical signal propagations while Fiber optics is a medium for
light propagation. It is the transmission of signal using light. Both are used to realize signal but
fiber realize ray signal and copper realize electrical signal. Single fiber optical cable used for
million and billion subscriber customers.
Network Topologies of FAN
Before Ethio telecom promote itself to a technology called MSAG. The old network topologies
of FAN used Main distribution frame (MDF) and cross connection cabinet (oldest exchange
box that works by legacy switch which contains only the copper cable to connect the network).
This is the old network topology of FAN used in Ethio-telecom
Figure 2. 1 The oldest FAN topology
Currently this topology is changed to the new technology which accommodates the Exchange,
MDF and CCC which is called MSAG, it improves adding fiber, data and also internet as new
version .
Figure 2. 2 The latest topology for copper access network
EXCH MDF CCC Terminal
Box(TB)
Centeral
office(CO)
MSAG
Terminal
Box(TB)
Subscriber

Figure 2. 3 The latest topology for fiber access network
❖ Under FAN division there are four sub divisions as figure below
Figure 2. 4 FAN division
❖ From Fixed access network subdivision majorly, I have been seen about
✓ Copper Access Network
✓ Backbone (Fiber Access Network)
➢ Transmission from O&M (from other division)
Centeral
office(CO)
MSAG
Patch
Panel
Subscriber
FAN
Backbone(Fiber
Access Network)
Copper Access
APD
PRO

2.3.1 Copper Access Network
It is subsection of FAN that connects the service provider to the customer through copper cable.
Copper cable is the oldest and most common transmission media. It can be used for the short
distance connections between the local exchange and subscribers.
Many kinds of copper cable this are:
➢ Aerial Cable: is an overhead cable which install from pole to poles.
➢ Underground Cable: are buried under the earth using ducts. Most of the underground
cables are polyethylene cable
➢ Submarine cable: Submarine cable is a cable laid on the sea bed between land-based
stations to carry telecommunication signals across stretches of ocean.
➢ Jumper wire
➢ Drop wire
❖ Under Copper Access Network majorly we have been seen about
1. Multiple Service Access Gateways (MSAG)
2. Materials used in copper access network
3. Work performed under Copper Access Network
4. Color Codes of a Copper Wire
1. Multiple Service Access Gateways (MSAG).
MSAG is stand for multiple service access gateway, because it is an access device for data,
internet and voice also a device typically installed in a telephone exchange and a roadside
serving area interface cabinet which connects customers’ telephone lines to the core network,
to provide telephone, ISDN, and broadband such as DSL all from single platform. They are the
main components which I was working on my internship.it is the latest technology that is
implemented in Ethiopia by the company ZTE and Huawei which has one fiber input from
local switch and 1-1000 output copper lines (the overall number of broad band and voice lines)
and mainly develops VOIP services and broadband data services over the IP network. MSAG
enables service access such as analog telephone set and broadband services under the control

of the soft switch. The phone services are providing by soft switch (SS) and broad band services
are provided by internet. It is a big rectangular box which has different part in it.
Figure 2. 5 MSAG
MSAG contains master shelf, four slave shelves, primary part, secondary part, Slot, Pair, One
power distribution box and Batter. Those different part of MSAG can operated and maintained
by different work divisions of site workers or technicians, that preserve the copper access
network of fiber access network for customers act as get way.
1.1 There are Different types of Cards in MSAG
Card in MSAG is mainly exist on Master shelf (zero shelf) and four slave shelf part of MSAG,
as we see there are many parts of MSAG in which different department of ethio telecom operate
on it, let as we see generally about card and its functions
✓ zero shelf (main shelf)
✓ shelf one
✓ shelf two
✓ shelf three and
✓ shelf four

Figure 2. 6Master shelf and Slave shelfs on MSAG
Zero shelf also they call as main shelf which mainly used for data service, Shelf one is mainly
used for internet service, shelf three and shelf four are user for voice service. The fiber cable
from Ethio Telecom (in NNOC) will be installed and when it reaches the MSAG, the lines will
be divided in to data, internet and voice and will be inserted to their respective cards, here there
are also lines which comes for optical fiber customers and they will get in to the fiber processing
card [1],Also, there are many cards on each shelf some of them are:
I-Subscriber Card
II- Control and switching Card
III-VOIP Card
IV-Interface Card
V-Test Card
VI-Power Card

Figure 2. 7 Cards on MSAG
I. Subscriber Cards: Subscriber cards contain the following types
➢ Analog subscriber cards: ALC, RALC& FLC
➢ Integrated line subscriber cards: ILC& GILCA
➢ Broadband subscriber cards: ADL, GVDL, EPON, VDL&SDL
➢ x PON cards contain the following types: -
✓ EPOL: 1–port EPON OLT interface card
✓ EPOI: 1–port EPON OLT interface card
✓ EPNI: EPON uplink interface card
• ALC Card: The ALC card provides 32 ports for analog subscriber service access. It
supports POTS, Function of the ALC card supports the following basic BORSCHT
functions: - B (Battery): Feed function, O: Over voltage protection, R: Ringing, S:
Supervision, C: Coding and decoding: Hybrid 2-/4- wire conversion: Test function
• RALC Card: The RALC card provides 32 ports for analog subscriber service access. It
supports POTS function.
The RALC supports the same BORSCHT functions as the ALC card. It also supports
polarity reversal function.
• GILCA Card: The GILCA card provides a 16-port interface for ADSL/ADSL2+
broadband service access and a 16-port interface for analog subscriber service access. The
broadband access interface and analog voice access interface are integrated as one via the

built-in splitter on GILCA card. In this way, the GILCA card provides broadband and
narrowband service access via a pair of twisted pairs cable.
• GVDL Card: The GVDL card provides 16 ports for high-speed VDSL2 service access.
and it also provides the mixed insertion.
• EPOI Card: The EPOI card implements OLT functions in an EPON system. It provides
one EPON port and supports 32 ONUs at most. The downstream/upstream rate reaches up
to 1.25 Gbps.
II. Control and Switching Card
ZXMSG 5200 supports four types of control and switching cards. those are, ICS, EICS, GIS
&GISS These controls and switching cards implement data switching, system management,
clock Processing and active/standby function management.
III. VoIP Processing Card
The VoIP processing card forwards VoIP voice signals and fax signal. To implement basic call
service and other value-added services, the VoIP processing card supports the following
functions: DTMF detection /generation, Tone and voice generation, CID
receiving/transmitting& Conference phone resources
The ZXMSG 5200 supports two types of VoIP processing cards: MPR and MPRB.
IV. Interface Cards
The ODTI card is an octal digital trunk interface card. It resides in Slot 8. The ODTI card
implements the 8 × E1 expansion function by performing the conversions between the two 8M
HW and eight E1 signals.
V. Test Card
There are three types of TSLC card: TSLCC, TSLCD and TSLCE. TSLCD/TSLCE can be
inserted in any subscriber card slot. TSLCC can only be inserted in the specified slot.
The TSLC card implements the following functions: External line test, Internal line test,
Subscriber telephone function test &Interception function

VI. Power Card
Supplies secondary power and ringing current for all subscriber shelves.
Functions: it converts +48v dc power to 24v or 12v ac power according to different card
requirements, it provides assistance for other power cards at all layers& it Supplies four types
of voltages: - +5v, -5v, -48v and 75v AC ringing current.
1.2 How to maintain (preserve) the Copper Access Network On MSAG?
In generally MSAG have many parts in which many divisions work out on it from that they
used the primary and secondary part of MSAG to preserve the copper access network on
MSAG the there are three main shelves on primary side of MSAG namely:
✓ Shelf zero
✓ Shelf one
✓ Shelf two
Shelf Zero: Shelf Zero on primary side of MSAG is the upper most 12 cards part on MSAG
which gives internet service for customer, but by default there are 16 cards but 4 of them are
used internally for other purpose such like power. In this shelf 16 customer are access in one
port and the technician start to count from 1001 upto1080, the technicians start counting from
fist card by saying 3,4,5,6,7,8,11,12,13,14,15,16, they jump the 1, 2, 9 and 10 that are used for other
purpose internally.,
Shelf One: Shelf One on primary side of MSAG is next to the zero shelf, for shelf one 16
customer are access in one port and the technician start to count from 1211.it’s gives for data
customer.
Shelf two: shelf two is the shelf the shelf next two, for shelf two 32 customer are access in
one port and the technician start to count from 230. It gives for voice customer and the rest
cards are given to voice because in our country context there are large number of PSTN users
compared to ADSL internet or data users, hence there is no surprise to give the most cards for
voice.
Also, the primary and secondary part of MSAG contain port, frame &fuse.
Port: It exists in the multi-service access get at primary box. The port which connected with
copper cable in the main distribution frame (MDF) and using the jumper rope link to the frame
at secondary box.

Frame: The frame is existing in the main distribution frame (MDF) frame at primer and
secondary line. One horizontal frame which exists in the secondary box is give service for
twenty-five customers.
Fuse: It is one part of communication device which used to the MSAG and MSAG with the
customer. It exists at secondary and primary side of MSAG.
Figure 2. 8 primary and secondary side of MSAG
2. Material Used in Fixed Access Networks
a) Terminals: Those devices are network elements before the customer’s device. The
MSAGs are connected to those devices through copper wire and the customer will be
connected to those devices directly. But they have nothing to do other than connecting the
MSAG and the customer. They are used to make the installation of wires form the MSAG
to the customer simple. For example, in order to give service for 10 customers, one
overhead or underground cable with 10 pairs will be connected to the MSAG and then to
the terminal instead of installing 10 different wires for those customers then connect them
directly from the terminal.

Figure 2. 9Terminal
b) ADSL (Asymmetric Digital Subscriber Line): - It converts the ordinary telephone line
into a high-speed passage for digital audio, video and data. ADSL technology is widely
used for business and personal purpose. The technology is simple as the setup required for
network already exists. However, the speed depends on the distance between the Internet
service provider and the user. More the distance, less will be the speed of the Internet
access. It is a type of digital subscriber line internet services commonly used in customer
home, if the customer needs speed of less than 3M.
Figure 2. 9 ADSL

Internship Report 2019
ADSL a type of digital subscriber line (DSL) technology, a data communications technology
that enables faster data transmission over copper telephone lines than a conventional voice
band modem can provide. ADSL differs from the less common symmetric digital subscriber
line (SDSL). In ADSL, Bandwidth and bit rate are said to be asymmetric, meaning greater
toward the customer premises (downstream) than the reverse (upstream). Providers usually
market ADSL as a service for consumers for Internet access for primarily downloading content
from the Internet, but not serving content accessed by others. ADSL works by using the
frequency spectrum above the band used by voice telephone calls. With a DSL filter, often
called splitter, the frequency bands are isolated, permitting a single telephone line to be used
for both ADSL service and telephone calls at the same time. ADSL is generally only installed
for short distances from the telephone exchange (the last mile), typically less than 4 kilometers
(2 mi), [2] but has been known to exceed 8 kilometers (5 mi) if the originally laid wire gauge
allows for further distribution. At the telephone exchange, the line generally terminates at a
digital subscriber line access multiplexer (DSLAM) where another frequency splitter separates
the voice band signal for the conventional phone network. Data carried by the ADSL are
typically routed over the telephone company's data network and eventually reach a
conventional Internet Protocol network. There are both technical and marketing reasons why
ADSL is in many places the most common type offered to home users. On the technical side,
there is likely to be more crosstalk from other circuits at the DSLAM end (where the wires
from many local loops are close to each other) than at the customer premises. Thus, the upload
signal is weakest at the noisiest part of the local loop, while the download signal is strongest at
the noisiest part of the local loop. It therefore makes technical sense to have the DSLAM
transmit at a highe r bit rate than does the modem on the customer end. Since the typical home
user in fact does prefer a higher download speed, the telephone companies chose to make a
virtue out of necessity, hence ADSL.
The marketing reasons for an asymmetric connection are that, firstly, most users of internet
traffic will require less data to be uploaded than downloaded. For example, in normal web
browsing, a user will visit a number of web sites and will need to download the data that
comprises the web pages from the site, images, text, sound files etc. but they will only upload
small amount of data, as the only uploaded data is that used for the purpose of verifying the
receipt of the downloaded data or any data inputted by the user into forms etc. This provides a

justification for internet service providers to offer a more expensive service aimed at
commercial users who host websites, and who therefore need a service which allows for as
much data to be uploaded as downloaded. File sharing applications are an obvious exception
to this situation. Secondly internet service providers, seeking to avoid overloading of their
backbone connections, have traditionally tried to limit uses such as file sharing which generate
a lot of uploads.
c) Signal finder and Tone generator: - are used to find the exact position of the fault and
check the proper line for the customer from port side or secondary side to TB and also from
TB to customers home. the tone generator generate the tone and it have two outlets so we
attach it to telephone line, the signal finder finds the tone generated by the tone generator
through telephone line and identifies where we lost the tone.
Figure 2. 10Signal finder and tone generator
d) Insertion tool: - is mechanical tool used for insert jumper wire and cut unwanted jumper
Wire
Figure 2. 11 Insertion tool

e) Head set: - is used to check whether there is tone or not on the port, on ADSL line and also
Frames. there is different tone that the head set detect whether or not the signal is reached
the place where we check it. the tone is generated in other side of MSAG.
Figure 2. 12Head set
f) UY connector: is one of wire splice connecter used for connecting two wires together
Figure 2. 13 UY connector
g) Ladder: is manufactured in aluminum and it provides excellent balance and support at the top
of the ladder.
Figure 2. 14 ladder
h) ADSL splitter: -a splitter or filter is essential wherever a telephone or other device shares
a line with an ADSL modem. And eliminate the high frequency noise used by ADSL
service from being heard on the phone and it perform the same function but in the two
ways.
.
Figure 2. 15 ADSL splitter

3. Work Under Copper Access Network CPE configuration
✓ Survey
✓ Copper Installation
✓ CPE configuration
✓ Termination
✓ Trouble shouting telephone, FAX machine lines and ADSL lines
Survey: when the customer requests order from Ethio telecom the survey team will go to the
address specified and look the closest terminal and MSAG number and the distance from the
terminal as well as the MSAG. Then report back with the closest MSAG and terminal. Then
the new connection order will be sent to the IP provisioning team if the customer is an internet
customer and data customer. Once the new connection order is received by the IP provisioning
team the configuration will be done on the appropriate device it may be on the routers on the
MSAG.
Copper Installation: After the supervisor of the FAN copper team receives customer orders
from customer services or sales team, he will distribute the work orders to the group of teams
he organized under him as a super visor. Then the line technicians will go to the specified
MSAG and Terminal by looking the order gained after survey is done and then we will check
whether the signal reaches or not. First, we checked on the MSAG primary and then on the
secondary if both are ok, we will go to the terminal which is at the close proximity to the
customer and we will check if the signal reaches there we will connect to the CPE (customer
premises equipment) which may be fax machine fixed line telephone or ADSL modem.

If the connection is to the ADSL modem which means if the customer is ADSL subscriber the
CPE configuration order will come next. I will explain what we did in the CPE configuration
order below
CPE configuration: CPE is Customer Premise Equipment, The CPE configuration in Copper
team is only done on ADSL modem configuration and now they are migrating to the VDSL
modem which supports up to 56Mbps downstream and 16 Mbps up stream because of there is
a scarcity in EPON modem to use for fiber installation.
Asymmetric digital subscriber line (ADSL) is one form of the digital subscriber line, a data
communications technology that enables faster data transmission over copper telephone lines.
Through ADSL customers will get a better, affordable, reliable and faster internet connection
starting from500 birr per month. This service is used by banks, institutes and etc. Ones
customers can buy the CPE with ADSL modem the configuration is done by technicians also
while it losing the existing configuration the technicians re configure it with some steps[8].
The steps in in the ADSL configuration are as follows.
Step One: Accessing the modem: the default gateway to the modem is 192.168.1.1 which
private address in class C Ip address ranges after we write the address and press enter it will as
for the authentication user name-admin and password admin is the default user and password
after we enter the correct user name and password we will be prompted to the GUI running or
the browser done by the manufacturer of the modem in the case of Ethio telecom ZTE.
Figure 2. 16 step one of ADSL configuration

Step Two: when we click on the quick setup the following interface will be displayed what we
need to do is pressing next with out changing any parameters from those listed.
Figure 2. 17step two (a) of ADSL configuration
Figure 2. 18 step two (b) of ADSL configuration
Step Three: check PPOE for Residential and MAC encapsulation for enterprise customers and
press next

Figure 2. 19Step three of ADSL configuration
Step four: The most important information will be filled in this step The Private one IP sub
net mask and default gate way primary and secondary DNS server addresses. Wan IP address
and other related numbers are provided by ethio Telecom during sales. The WAN IP is the IP
assigned for the interface of the modem and the incoming RJ-11 connector. And the default
gateway is the point where our computer is connected to the modem or maybe we might
connect a switch to our modem if we want to have larger network. Whatever the device we
connected to the modem that interface is called the default gate way and the default gate way
IP address is assigned automatically but we will also fill in the next step as a primary IP address.
And we have to enable NAT which means network address translation because the class C
private address have to be translated to the class A private’s address and that class A private
address will be translated to the public IP address as well because private addresses are not
routable on the internet. If we are doing for data customer, we don’t need to enable NAT
because the address does not need to be translated because we do not need it to route over the
Internet Ruther the user in the LAN will communicate each other securely without going over
the internet

Figure 2. 20 Step four of ADSL configuration
Step five: In this step we will fill the primary IP address which is the default gate way and the
subnet mask will be filled automatically .and other thing is we need to enable dhcp so that the
modem will assign an ip address automatically to the computer or devices connected to the
network and we can use the whole possible ip addresses from 192.168.1.2-192.168.1.254
Figure 2. 21Step five of ADSL configuration
Step six: when we press next in the above step we will be prompted to the summary of our
configuration what we need is check if the whole information is correct if it is correct click
apply and if not return back and reconfigure it.

Figure 2. 22 Step six of ADSL configuration
Termination: when the customer wants to end the services, he/she was using by any means
the customer will apply to stop the service. In the same way as the new order is done the IP
provisioning team will remove the configuration from the access devices the router or BRAS.so
that it will be ready for another customer to be configured. Once the IP professional do this the
FAN copper team will go to the customers residence and uninstall the line installed from home
to terminal and from terminal to the MSAG as well.
Trouble shouting telephone, FAX machine lines and ADSL lines: The trouble shooting
process is almost similar check the connection if there is any open or short on the line using
different mechanisms using Tempo meter or tone generator to check the continuity of the line
and fixing that fault. The difference is the tone we will here for the internet and data customer
is not the normal telephone tone but it is busy tone because it have to be always online.
The basic kind of faults that occur on all kinds of wire lines are
➢ Open circuits: - An open circuit occurs in a wiring line when one or both conductors are
broken or cut. An open circuit also occurs in poor splices.

➢ Short circuit: - Short circuit occurs when the conductor of pair come in contact with each
other.
➢ Crossed circuit:- Crossed circuit occurs when the conductor of one wire line comes in
electrical contact with the conductor of second or both wire lines
➢ Grounded circuit: - When a line is grounded, one or both line conductors are in contact with
a grounded
❖ Sometimes the ADSL modem losses its configuration due to some reasons so we will
reconfigure as we did for new configuration.
Figure 2. 23 ADSL architecture
4. Color Codes of a Copper Wire
Color code is a system of marking things with different colors as means of identification. For pairs
numbering 1 through 10, the pair identification colors are outlined below. In cable constructions
containing more than 10-pair, the colors are repeated as necessary. Color coded binders are used to
identify 10-pair groups of color-coded pairs
Table1. 1Color Code of Copper
Pair Number Tip Color Ring Color
1 white Blue
2 white Orange
3 white Green
4 white Brown
5 white Grey
6 Red Blue
7 Red Orange
8 Red Green
9 Red Brown
10 Red Grey

2.3.2 Fiber Access Network
It is subsection of FAN that connects the service provider to the customer through fiber optics,
fiber optics is a medium for the transmission of signal or information’s using light, the light
forms an electromagnetic carrier wave that is modulated to carry information. Single fiber
optical cable used for million and billion subscriber or customers.
Fiber optic is; Safer that is nonconducting & not a high voltage, have very high resistance to
noise, have excellent security, ability to carry much longer distances before requiring repeaters
than copper cable, also it’s industry standard for high-speed networking.
There are two major types of fibers: Single mode fiber and Multiple mode fiber
Single Mode Fiber: is a single stand of glass fiber with a diameter of 8.3 to 10 microns that
has one mode of transmission. Single Mode Fiber with a relatively narrow diameter, through
which only one mode will propagate typically 1310nm or 1550nm. Carries higher bandwidth
than multimode fiber, but requires a light source with a narrow spectral width. Synonyms
mono-mode optical fiber, single-mode fiber, single-mode optical waveguide, uni-mode fiber.
Single-mode fiber gives you a higher transmission rate and up to 50 times more distance than
multimode, but it also costs more. Single-mode fiber has a much smaller core than multimode.
The small core and single light-wave virtually eliminate any distortion that could result from
overlapping light pulses, providing the least signal attenuation and the highest transmission
speeds of any fiber cable type.
Single-mode optical fiber is an optical fiber in which only the lowest order bound mode can
propagate at the wavelength of interest typically 1300 to 1320nm.
Single-mode has a much smaller core that allows only one mode of light at a time through the
core. Multimode is the first type of fiber to be commercialized. It has a larger core than single-
mode fiber.
Multimode Fiber: is made of glass fibers, with a common diameter in the 50-to-100-micron
range for the light carry component (the most common size is 62.5). POF is a newer plastic-
based cable which promises performance similar to glass cable on very short runs, but at a
lower cost.

Multimode fiber gives you high bandwidth at high speeds over medium distances. Light waves
are dispersed into numerous paths, or modes, as they travel through the cable’s core typically
850 or 1300nm. Typical multimode fiber core diameters are 50, 62.5, and 100 micrometers.
However, in long cable runs (greater than 3000 feet [914.4 ml]), multiple paths of light can
cause signal distortion at the receiving end, resulting in an unclear and incomplete data
transmission.
Figure 2. 24Multi-mode and single-mode fiber
A fiber optic data link sends input data through fiber optic components and provides this data
as output information. It has the following three basic functions:
➢ To convert an electrical input signal to an optical signal
➢ To send the optical signal over an optical fiber
➢ To convert the optical signal back to an electrical signal
❖ Under Fiber Access Network majorly we have been seen about
1. Materials used in Fiber access network.
2. Common faults in Fiber access network.
3. Works under fiber access network.
4. Fiber Color Coding.
1. Materials used in Fiber access network
a. EPON (Ethernet passive optical networks) It is a group of technology that provide high
speed internet access by using optical fibers. It is used if the customer needs 3M and above

Figure 2. 25 EPON.
b. OTDR (Optical Time Domain Reflect meter) – it is used to characterize the losses and
the length of the losses in optical fibers, mainly the losses that are caused by splice. It
locates defects and faults, and determines the amount of signal loss at any point in an optical
fiber. Generally, OTDR machine is used for Measuring the distance between two points on
fiber cable link, locating fiber cable cuts/breaks, and Identifying sharp bends/cracks in
optical fiber links that affect the signal power.
Figure 2. 26 OTDR
c. Fusion Splicing Machine: - Fiber splicing is the process of permanently joining two fibers
together. Unlike fiber connectors, which are designed for easy reconfiguration on cross-
connect or patch panels. There are two types of fiber splicing – mechanical
splicing and fusion splicing.
Mechanical splicing doesn’t physically fuse two optical fibers together, rather two fibers are
held butt-to-butt inside a sleeve with some mechanical mechanism. You will get worse
insertion loss and back reflection in mechanical splices than in fusion splices (the second type
we are introducing below). Mechanical splicing is mostly used for emergency repairs and fiber
testing.
The second type splicing is called fusion splicing. In fusion splicing, two fibers are literally
welded (fused) together by an electric arc. Fusion splicing is the most widely used method of
splicing as it provides for the lowest insertion loss and virtually no back reflection. Fusion

splicing provides the most reliable joint between two fibers. Fusion splicing is done by an
automatic machine called fusion splicer (fusion splicing machines).
Figure 2. 27Splicing Machine
As we said above, fusion splicer is the machine used to weld (fuse) two optical fibers together.
This process is called fusion splicing. The fiber ends are prepared, cleaved, and placed in
alignment fixtures on the fusion splicer. At the press of a button, the fiber ends are heated with
electrodes, brought together, and fused.
There are five basic steps to fusion splicing with a splicing machine.
Step1 :Put on the fusion splice protection sleeve
Step2: Strip the fiber. Strip back all fiber coatings down to the 125um bare fiber. Clean
the bare fiber with 99% isopropyl alcohol.
Step3: Cleave the fiber. The fiber needs to be cleaved with a high precision cleaver. Most
splicing machines come with a recommended cleaver. Fiber cleaving is a very important
step as the quality of the splice will depend on the quality of the cleave.
Step4: Put the fibers into the fiber holders in the fusion splicer. Press the start button to start
the fusion splicing
Step5: Heat shrink the protection sleeve to protect the splicing joint
d. Cutting machine/cleaver: - cleaving is the process by which an optical fiber is cut or
precisely broken for termination or splicing. Just like cutting glass plate fiber is cut by
scoring or scratching the surface and applying stress so the glass breaks in a smooth manner
along the stress lines created by the scratch. the fiber will cleave with a clean surface
perpendicular to the length of the fiber, with no protruding glass on either end.

Figure 2. 28Cutting machine/cleaver
e. Protection sleeve: -a good protection for the spliced fibers during fiber optic splicing is
extremely necessary. Fiber protection sleeve perfectly solve the issue. It acts as strong coat
for the fiber splice to prevent unpredictable fractures
Figure 2. 29Protection Sleeve
It consists of three parts. The first part is the inner tube made by hot-melt able adhesive. This
material can encapsulate the fusion splice joint and provide vibration damping and an
environmental goal so as to protect the fiber from damage and contamination. The second part
is a reinforcing strength member outside the inner tube. The strength member can be made of
stainless steel, ceramic or non-metallic. It offers extra rigidity to prevent misalignment, micro
bending or breakage of the fiber. The third part is heat shrinkable outer tube made of cross-
linked polyolefin. This tube provides adhesive an instant shrink force and drives the adhesive
liner in to all areas of the splice and excludes all the air.
f. Power meter and handle light source meter
An optical power meter (OPM) is a device used to measure the power in an optical signal. The
term usually refers to a device for testing average power in fiber optic systems. Optical power
meter consists of a calibrated sensor, measuring amplifier and display. The sensor primarily

consists of a photodiode selected for the appropriate range of wavelengths and power levels.
On the display unit, the measured optical power and set wavelength is displayed
Figure 2. 30 Optical Power Meter
g. Fiber Optic splices closure (FOSC): Fiber optic splice closure is the equipment used to
offer room to fuse splice optical fiber and also to provide protections for the fused fiber
joint point and the fiber cables. Typical fiber optic splice closure and vertical type and
horizontal type, there are various kinds of fiber splice closures suit for different
applications, such as aerial, duct fiber cables and direct buried.
Generally, fiber optic splice closures reused outdoors, some even used underwater.
Figure 2. 31 Closure
For outside plant splice closure, there are two major types: horizontal splice closure and vertical
splice closure,

Fiber Optic Splice Closure Installation Steps: Here I will outline the main steps involved in
fiber splice closure installation. For more detailed steps,
1. components in the enclose
Fiber optic splice closure kit usually includes: end plate, splice tray organizer, fiber
splice tray, cover, cable grommets, grommet retainer, mounting bracket and misc.
hardware
2. Fiber Cable Sheath Preparation
2.1 Expose the rip cord. This step involves mark the location with a tape marker, ring-
cut the outer jacket with a sharp knife, remove the corrugated armor if applicable,
and shave off the outer jacket to expose the rip cord.
2.2 Remove the outer sheath. This step involves make a longitudinal slit down the outer
sheath, peel off the outer jacket and corrugated metal, can cut the rip cord flush with
the end of the corrugated metal.
2.3 Remove the inner jacket. This step involves using the rip cord under the inner jacket
to slit it, cut aramid yarns, cut central strength member, and clean the filling
compound
3. Bonding and Grounding Hardware Installation
Bond clamp installation. This step involves slide the cable clamp over sheath, slide the
bond shoe under the corrugated metal, place the bond plate over the bond shoe and
secure the sheath grip
4. Assembly of Cables to Splice Closure
The preferable location for the two main cables is in the lower end plate port. If a third
or fourth cable is required, it is easier to install it in the upper end plate port as a branch
cable. This fiber optic splice closure is designed for two cables in each of its two ports.
If only one cable will be installed in a port, the provided rubber grommet plug is used
to substitute for the second cable
4.1. Install Cables to End Plate. This step involves unscrew knob and remove
grommet retainer, position the end plate assembly, attach the sheath grip to
dielectric cables, slide cables and sheath grip through, and secure sheath grip
to backbone.
4.2. Grommet Installation and External Grounding. This step involves apply B-
sealant, push the grommets into the end plate port, and apply more B-Sealant.

4.3. Fiber Unit Preparation and Distribution Organizer Installation. This step
involves remove more loose tubes, separate each cable's loose tube into two
groups, position the distribution organizer, secure the loose tubes to the
distribution organizer, and secure the loose tubes.
4.4. Splice Tray Installation. This step involves place the splice tray, fasten the end
of the splice tray to the organizer, and install cables, grommets and external
ground.
4.5. Optical Fiber Splicing. This step involves splice holder placing, fiber splicing
and fasten the splice holder lid.
5. Fiber Optic Splice Closure Cover Installation
6. Closure Mounting
7. Reentry
h. Patch panel: - patch panel is a passive device that has a row of ports, which is used for
cable management to bundle multiple network ports together to connect incoming and
outgoing cables. The ability to label individual cable runs in a patch panel creates a clean
and organized way of identifying signal flow and troubleshooting technical problems,
mainly connecting and routing circuits for monitoring, interconnection and testing circuits
in a convenient, flexible manner. Patch panel are commonly used in computer network.
Computer network makes use of switches, which are essentially patch panel, allowing
eight, sixteen or more computer to be connected to a single device.
Figure 2. 32Patch panel
i. Fiber optic patch cord: -also known as fiber jumpers or fiber patch cords are a
transmission medium made of glass used to transmit data via light. Patch cords are
classified by transmission medium (long or short distance) by connector construction and

by construction of the connecter’s inserted core cover. Connector design standards include
FC(Ferrule connector), SC(Subscriber connector), ST(Straight Tip), LC(Lucent
Connector), and MTRJ(Mechanical transfer Register Jack) and so on. Cables are classified
by the connectors on either end of the cable. Same of the most common cable configuration
include FCFC, FC-SC, FC-LC, FCST, SC-SC, and SC-ST.
Figure 2. 33 Patch Cord
2. Work mainly done under fiber access network
The main responsibility of this team in Ethio telecom is to solve troubles happening in related
to the back bone which is the fiber optical cable connecting the MSAGs to other MSAGs. the
MSAGs to the switches, edger routers to core routers, core routers to border routers, border
routers to the Gate way routers. And each large-scale networking devices to each other. In
addition to this to troubleshoot the common fault the fault occur under fiber like, cut of fiber ,
bending of fiber , the decrease of speed of internet in fiber customer and also the back bone
section also works on FTH services for customers who need higher band width which cannot
be addressed by copper which is above 5 MB according to the working trends of Ethio telecom.
When there is a damage among the back bones the fiber will be re spliced based the color codes
of the fiber unlike simply connecting like copper it needs relatively complicated process to
connect the broken fiber.
Fiber Optic Splicing: Fiber optic splicing is an important method of joining two fiber optic
cables together. It is a preferred solution when an available fiber optic cable is not sufficiently
long for the required run. Besides, splicing is designed to restore fiber optic cables when they
are accidentally broken. Nowadays, fiber optic splicing is widely deployed in
telecommunications, LAN (Local Area Network) and networking projects.

3. Fiber Color Coding
A fiber industry uses a standard of repeating of 12 colors. When cables go beyond 12 units, the
colors repeat but use a stripe to distinguish units. Individual tubes containing 24 fibers have a
blue and orange colored binder thread separating the two 12 fiber groups 2.4
Generally, the work we have been executing in our section as it is mentioned before, our
section was fixed access network which includes copper and fiber as well as NNOC but due to
lack of time I didn’t see NNOC rather I transferred to transmission from O&M. In fiber section,
we spliced fiber optics core using splice fusion material. we were trained how to splice the fiber
core by the fiber optics technicians. Then, we are allowed to splice these cores when there is a
sudden cut of cable or when a new customer applies to get an internet service. In copper section,
we connect the primary and the secondary part of copper distribution cabinet using a jumper
wire, and maintain fixed line telephones.
2.3.3 Transmission
Transmission may be defined as the electrical transfer of a signal, message, or other form of
intelligence from one location to another and also a process of transferring any coming
network, signal, message from stakeholder to the central exchanger and again that comeback
in to the user. The pathway that carries the information from sender to receiver is called
Transmission media. We use different types of cables or waves to transmit data. Data is
transmitted normally through electrical or electromagnetic signals. These signals can be
transmitted through copper wires, optical fibers, atmosphere, water and vacuum Different
Medias have different properties like bandwidth, delay, cost and ease of installation and
maintenance. Transmission media is also called Communication channel. There are two type
of transmission media one is Wired or Guided Media or Bound Transmission and the other one
is Wireless or Unguided Media or Unbound Transmission Media. The diagram below shows
the two types of Transmission media. Under the transmission division they mainly use wired
or guided media with fiber and copper cable.

Figure 2. 34Type of Transmission media
➢ Under Transmission majorly we have been seen about
1.Part of Multiple Service Access Gateways (MSAG)
2.Major functions of transmission division
3.Material used In Transmission division
4.Common faults in that troubleshoots by Transmission division
1. Part of Multiple System Access Gateways (MSAG)
➢ As whole the Transmission is operating /working in the MSAG by the ways of:-
Figure 2. 35 Operating System of Transmission on MSAG
The transmission process will be working/operating by linking of fiber optics with two different
line (i.e., line A and line B). Each line that of A and B are having input-OAD and output-OAD,
like as: -
The arriving/ incoming message, signal, network is concealing inline-A (ETH1), and then
it is departing/ outgoing in line-A (ETH2).
The arriving /incoming message, signal, network is concealing inline-B (ETH1), and then
it is departing /outgoing in line-B (ETH2).

1.1. How to maintain (preserve) the transmission on MSAG?
➢ Mainly transmission department focus on the MSAG part on the figure below in addition
some parts of cards on MSAG.
Figure 2. 36 Transmission part of MSAG
It can have, ETM card, incomming inline-A,B (ETH1) and departing/ outgoing in line-A,B
(ETH2).
1.2. How ETM-CARD operate/work?
ETM is operate by blinking of a green color on both GE2 and NACT, which mean that GE2 is
used to receive (RX) and transmit (TX) data and NACT is used to up the system then the card
will be activate. If GE2 is blink then ETM-P2 will be activate with the wave length 1491nm
and GE1 is also blink/not then ETM-P1 will be activate with the initial wave length 1471nm.
In generally, the wave length is increase/far from the central NNOC then the quality of signal
is reduced and the wave length is decrease/near to the central NNOC (exchanger) then the
quality of signal is stable.
➢ There are two basic sending and receiving process in the MSAG-System. These are: -
a) OAD and
b) OMD
A. OAD
• It stands for optical added and dropped.

• Mainly it used to select/dropped the network/message/signal for its want and send to The
remain network/message/signal that of one-lambda is dropped and seven-lambda are send.
This system takes place for balancing.
• On this system the wave-length does not seen evidently which are taking by considering.
• It reduced the amount of surplus/unwanted signal/clamor due to the incidence/presence of
selection.
B. OMD
• It stands for optical multiplexer and de multiplexer.
• Chiefly it used to propel/send the all coming network/message/signal in to the exchanger.
• Failure/losses are happened due to the absence of selection.
• The wave-length will be seen able to clearly.
• It contains different types of generator, such as G1, G2 and G3.
NOTE: -G1 it is containing the stable/ordinary signal (networks). G2 and G3 is asset
weak/unstable networks so-called that such generators are mainly used for regenerate/up-
grade the feeble/wobbly networks (signal) that coming on each bearing.
2. Major functions of transmission divisions
In generally the major work performed by transmission are such as confirm the master
exchanger or GIS, checkup the fiber board, checkup the power board, well verify the ETM-
CARD, principally applicable the optical power meter, looked GE1, GE2, and NACT are blink
or not, troubleshooting fault occur on ETM-cards and ODF.
3. Material used In Transmission
a) Optical Power Meter (OPM).
An optical power meter (OPM) is a device used measure the power in an optical signal.
The term usually refers to a device for testing average power in fiber optic systems
Figure 2. 37optical power meter

b) Optical Attenuator.
Attenuator is an electronic device which used to reduce the power of signal with-out the
appropriate deformation / bend of the wave-form. Mostly it can be applicable in Threshold
networks for increase the minimum one and decrease the maximum-one.
➢ In generally the optical attenuator is grouped in three, such as:-
a. Variable attenuator.
b. Line attenuator.
c. Connector attenuator.
Figure 2. 38Different type of attenuator
4. Common faults in Transmission
✓ Power down: occurs while there is no power faded to MSAG
✓ Card failures: occurs while there is some internal trouble in card
✓ ODF failure: occurs due to unstable of optical signal.
2.4. Procedures I have been using while performing my work tasks
As I discussed before, our task was performed in two different sections in FAN on Copper
Access Network and Fiber Access Network and in O&M on Transmission Section. Thus, are
site and office work by follow the following procedure: -
1. Understanding general MSAG, Primary and Secondary part of MSAG, Functions of some
cards on MSAG.
2. Read the type of fault occur report.
3. Identifying the types of maintenance.
4. Differentiating/knowing the faults on MSAG like Alarm and notification check, Equipment
running status check and Module fiber check.
2.5. My performance at the company
I have been executing as an assistant on FAN network division by executing some works
(duties) such as: -

✓ Supervising the works that have been done.
✓ Discussing on FAN problem & giving solutions.
✓ Checking alarm and notification.
✓ Checking the equipment running status.
✓ Cleaning the equipment’s
2.6. Challenges I have been facing while performing my work tasks
Since the ethio telecom is on the way developing country’s network infrastructure most of our
work was on site. While practicing on the development of the new network installation and on
office period we have faced some challenges. Those challenges lead us to take large care while
Performing any work. It also introduced us to take immediate measures after challenges faced.
Some of the main challenges are listed below are we have faced during the internship
program at the company. We have summarized the challenges we encountered during the
internship experience. The challenges we encountered are: -
✓ Having a smaller number of contacts with the supervisors due to we work all time on the
sight with the technician by moving from place to place.
✓ The great problem is the repetition of work and technician does not allow to us to do the
work by ourselves.
✓ The staff a member does was not able to believe us to observe and test all required thing
due to security.
✓ There were also lack of the car that is the capacity of holding people while we were going
to field.
✓ The shortage of money is also another difficult problem for the internship because of the
expensiveness of food and transportation.
✓ We didn’t get any pocket money form the company.
✓ The time of internships is summer that was the most challenging part while we out on-site
work there is a rain.
✓ No data manual regarding to our section FAN, the devices name is a full of abbreviation and
we haven’t learnt prerequisite courses for example networking etc.
✓ Unwillingness of company to give us access materials such as computer and usable
references for the security purpose.

✓ The technicians sometimes they didn’t know the place of customers house of fault occurred
and also the didn’t know the place of fault MSAG that was kill more of our time on
searching it.
2.7 Measuring or solution I have used for the challenges I have been facing
We have been tried to overcome to challenges that faced while we performing our tasks. The
order the at to overcome the challenges are the following:
✓ I have dot short notes at each practical time that help for the report.
✓ Communicated with my experienced friends and take the soft copy by flash and email.
✓ At lunch time I used the internet on the computer by choosing which is best for encourage
my goal.
✓ Some time I asked the company employer during the willing to help.
✓ By making observation repeatedly we minimize the error.
✓ Understanding the professional ethics of the work.
✓ I have used “do it now”, and “do it right” to overcome these challenges.
✓ We ask questions by identifying who is concerned for that working areas.

CHAPTER THREE
OVERALL BENEFITS GAINED FROM THE INTERNSHIP
From internship many experiences are gained when what theoretically learned is brought to
practical one. Therefor internship enables students comparing theoretical knowledge with
practical world. Generally, benefits gained from internship can be in terms of:
➢ Improving practical skills
➢ Upgrading theoretical knowledge
➢ Industrial problem-solving capability
➢ Improving interpersonal communication skills
➢ Improving team playing skills
➢ Improving leadership skills
➢ Understanding the work ethics
➢ Improving entrepreneurship skills.
3.1 Improving Practical Skills
As the main purpose of the internship at the university levelly is to facilitate or develop student
learning opportunities outside the class room, this experience provides the opportunity to apply,
class room theory to real word station. In our university even, the lecture try to take an initiative
measure to interconnect theoretical party with real practically part by taking in to the labs.
But there is not enough material in the labs, as result an internship was the right program to
improving our practical skills such as
➢ we able to see some part of exchange and its operation practical.
➢ What main MDF (main distribution frame).
➢ How we use jumper in order to connect the line side and exchange side.
➢ What does the MSAG internal including the card inside the MSAG.
➢ How to analysis the faulty in subscriber line by using tone generator and probe.
➢ How to know the location and cause of damage of fiber by using OTDR.
➢ How to splicing fiber by using the splice machine.
➢ How to give the broad band access to the customer by configuring DSL and EPON.
➢ Generally, we got a great experience how to telecommunication service is provided starting
from the exchange to home practical.

➢ We have got great experience in each staff of Ethio telecom such as, copper access network,
transmission, and fiber access network.
3.2 Upgrading Theoretical Knowledge
We believe theoretical lessons are a great foundation and prior thing you can’t get rid for
practical implementations. However theoretical knowledge developed by practical are
unforgettable, easily and quickly understandable and the main tool for problem solving. we
found the internship very important in up grading theoretical knowledge that we grasped during
the past four years. There were brand new ideas that we never got the chance to know about
when attending theoretical regular classes. The internship experience didn’t bring only new
ideas to the theory. Instead it helped in improving the available ways and ideas of problem-
solving skills to a great level. Specifically, on the area of optical fiber, electronics and data
communication we do have a great inspiration to work with full confidence since we enjoy the
most basics and practical implementations on this period. We upgrade our theoretical
knowledge and improving our experience in to one level. This are what is ADSL, EPON,
GPON, splice machine, OTDR, color code of fiber and copper and also whet is MSAG and its
function.
3.3 In terms of Industrial Problem-Solving Capability
We hope it is obvious that problem solving and decision making are key facets of any
successful operation. The first thing in solving a problem is to begin with a planning phase in
which the problem is clearly identified and understood each components or functional block in
the system and how it can fail. On the second stage you determine the effect of each problem
then determine the likelihood of occurrence and detecting the failure finally you came up with
the solution and check it out. After checking it out if the solution was not ok for the encountered
problem, going back to the first step and review the plan is the preferable method.
3.4 Interpersonal Communication Skill
The other thing we have improved is our interpersonal communication skill. While in the
campus, most of communication held informally. Besides that, our informal communication is
mostly limited in close friends. On the top of that we still do not make good team
communication. In this internship period, we have improved this informal communication, and
develop new formal communication skill. With the help of our associates, we have found many
options to develop these skills.
Interpersonal communication Skills that are critically we have improved include:

➢ Be careful about our body language: - Any physical barriers in between might create
detraction and can make the interpersonal communication process uncomfortable.
➢ Never interrupt: - Interrupting a person who is talking is not be recommended since its
disrespectful due to nobody like to be interrupted but it ok to make gentle interruption
saying sorry and ask the person if you can interrupt at the exact time.
➢ Be confidence of our idea: - Bing confident of what you are saying will increase the trust
that the other people have in you and make the conversation flow more freely.
➢ Listen well: - Good listening skill will be able to understand what the person says clearly
and react in positive manner so focus while you communicating with others.
3.5. Improving our Team Playing Skill
Being able to work well with team is nice beyond some demerits of being part of the team but
the nice part takes the weight. The qualities and skill we got enhanced me with are:
➢ Conflict-resolution: - These qualities offers resolving or managing conflicts effectively and
able to mediate problems between team members. Two approaches can help us in the
resolution these are:
➢ Give away: - this approach would be a better choice when the issue is less important than
the relationship.
➢ Cooperation: - this approach is fine when the teams have some areas of agreement on
which a mutually agreeable solution can be built.
➢ Listening: -we should demonstrate that we can listen to other people's ideas and points of
view by actively listening what others in the team have to offer and we can often build on
their ideas.
➢ Respecting: -treat all other team-members with equal respect and build up trust
➢ Helping: -we used to assume as essential to help others in the team. Be alert of what others
are doing and suggest help and support if we can.
➢ Sharing: -am willing to share knowledge, experience, time and talents with others in the
team.
➢ Asking: -we ask questions so we are sure of the objectives of the team.
➢ Persuading: -we have to be prepared to come up with ideas and persuade them, but
eventually agree to change them if they are correct.
➢ Participation: -we are willing to contribute enthusiastically to the team without dominating
other members, but we are also willing to lead and motivate when appropriate Being able
to work well with team is nice beyond some demerits of being part of the team but

3.6 Improving our Leadership Skill
Leadership is the most important skill that we think it is the most valuable skill that we develop.
Everything we used to think about leadership is changed in this internship period. We have
noticed that leadership need many skills. During the time of internship period we have
improved some of the following leadership skill
➢ Self Esteem: -we used to make someone feel important; we gain their willingness to work
for us. By:
✓ Asking their advice
✓ Remembering the name of the person am dealing with, and use it often in our
conversation
✓ Show reverence for a person's knowledge by repeating a statement of theirs
that will reflect positively on them.
✓ Become a Good Listener
✓ We stay alert in our posture and in our facial expression
✓ We try to avoid distractions.
✓ Get rid of bias in our thoughts about a person.
✓ Being patient until the person finished expressing his/her idea
➢ Motivating: - Our team members at all levels must feel they are needed. we cannot motivate
our team members if they do not feel essential to the process and our plan.
3.7 Understanding Work Ethics Related Issues
As work place ethics refers to choosing the option that is determined to be moral or legal right
choice, even if the other alternative is very attractive and even if you get away with the less
ethical choice, we understand the place ethics successfully. This means we are dedicated to job
that we assume valuable and productive. Some characteristics of good work ethics are
➢ Honest
➢ Respect to other.
➢ Cooperate
➢ Loyalty
➢ Transparence
➢ Punctuality
➢ Punctual

3.8 In terms of Entrepreneurship Skills
Entrepreneurship is defined as groups of people who organized or operate a business. We
understood that being an entrepreneur is not as simple as we have imaged before, rather it is
difficult to run because so many problems are expected to be faced. But it is also profitable, if
you are strong enough to face those problems, and a well-mannered and experienced managers
and human resource are assigned. The great thing that we have learned in terms of
entrepreneurship skill is to be bold to set up any kind of business and become profitable from
it, after you understand the concept of the business and get yourself familiarized with it.

CHAPTER FOUR
CONCLUSION AND RECOMONDATION
4.1 Conclusion
Ethio telecom was established before hundred years ago and it’s the biggest and well-organized
governmental company in Ethiopia. As we have got more information in this Internship period
Ethio Telecom is the back bone for the transformation by the side of communication and
offices, Schools and etc. Also, the services of telecom are very wide and basic for our country
development. The internship program is useful for improving and up grading theoretical
knowledge by practical skill and I had gained new practical knowledge, skill and the working
environment of Ethio telecom. We know Ethio telecom is the only telecom service provider in
Ethiopia and it provides internet, data, voice (mobile and fixed line telephone) and VPN service
to the entire country which telecom service is covered. In the section I have been worked I
understand that how we can get telecom service using fiber and copper cables as a transmission
medium. I conclude that fiber is much better than copper in data transmission because it
transmits many data at a time in forms of light. Now a day Ethio telecom uses fiber cable to
deliver internet service to the customer.
In general, the internship program is very important for engineering students by every direction
to develop the interest to learn more at the next time and to be having a good vision about
future. we got a good knowledge and we decide to do more on communication to be the next
generation strong worker.
4.2. Recommendation
Ethio telecom is a huge company that is profitable and we want to recommend for the future.
Even though the internship program has its own encouraged and highly advanced sides, but
there is some weakness that needs to be corrected as company level. These recommendations
are helpful for the company and the student will be well qualified skill. Some of they are listed
below:
❖ The company should give priority to safety and quality rather than economical profit, but
as we have observed in the company most of the devices are china products manufactured
at low price.

❖ Some staffs were not cooperative to explain things due to their lack of interest or sometimes
inefficiency as they get along with only the world of work. Others were too busy.
❖ The company should aim to serve its clients to the highest level of satisfaction, providing
the most appropriate and desired solutions with the best international standards of quality,
safety and environmental care to maximize the benefits of their stake holders, clients and
the community without overlooking ethical values on the professional and personal
development.
❖ It is better to rotation the students from one division to other division for the scheduled
time. This helps the students to capture all necessary knowledge in different divisions.
❖ The division that students take part must be only the divisions that their work has relation
with communication engineering.
I am glad to recommend that before engaging the students in the internship program, the
university should pay attention to the order of courses to be given which are supportive and
major courses for the interns, like courses related to telecommunication network, especially
engineering software simulation.

Reference
[1]. Dagim Tadele, “Organizational overview 1 v.3.ppt”, ethio telecom, 21th October, 2015
[2]. Gallaire,H, and Minker, J., eds. [1978] Logic and Databases, Plenum Press, 1978.
[3]. Elmasri, R., Kouramajian,v., and Fernando’s. [1993] "Temporal Database Modeling: An
Object-Oriented Approach, "CIKM, November1993.
[4]. Data and Computer Communications, William Stallings, ISBN 0-13-243310-9, ISBN 978-
0-13-243310-5
[5]. ICDE [1989] Proceedings of the IEEECS International Conference on Data Engineering
[6]. https://www.ethiotelecom.et/about-us/
[7]. Company Manual like DWDM, CWDM
[8]. www.firebase.google.com

Internship report on ethio telecom,@NAAZ

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