The document discusses the internship experience of an engineering student at PTCL, covering concepts learned in transmission, switching, MDF and DSL departments during a 6 week internship. It provides detailed information on the technologies, equipment, and processes within these departments, along with findings and recommendations from the internship.

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INTERNSHIP REPORT
TRANSMISSION, SWITCHING, DSL ,MDF
PAKISTAN TELECOMMUNICATION COMPANY LIMITED, ISLAMABAD.

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DEDICATION
I dedicate all my efforts and struggles of the educational life to my dear parents; without them I’m meaningless. Also I
devote the work of this internship report to respectable and honorable teachers who taught and supported me in
developing my personality as a competent professional.
ACKNOWLEDGMENT
This internship has been a very good experience for me in the way that it has given me the chance to understand the
real world outside the classroom. I have learnt a lot about the office environment and my interpersonal skills & self-
confidence have improved significantly.
First of all, I want to express all my humble thanks to ALLAH who is very sensitive about each and every activity Of
all his man and without whose help, I am unable to accomplish any objective in my life. Secondly, I am also thankful
to all staff of PTCL, for their valuable guidance and Support throughout the internship period. Further all other
executives and staff Members of PTCL deserve my thankfulness For their cooperation and guidance during the course
of my internship.
Engr Arshad Iqbal
BS-Telecom(IT)(Hons)
ROLL NO: 32535

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Table of content
Part 1: Introduction ……………………………………………...…….. 3
Part 2: Concepts learnt in different departments………….…..………. 3
2.1Transmission………………………………………………………….. 5
2.1.1Integrated Services Digital Network…………………...... 6
2.1.2 ZNOC…………………………………….…………….. 7
2.2Switching…………………………………………………………….. 10
2.2.1Modes of Switching……………………………………...…12
2.2.2NOC in PTCL…………………………………………… ...13
2.3 MDF(Main Distribution Frame)………………………….………..14
2.3.1PTCL Architecture…………………………………………14
2.3.2 Networks…………………………………………………..14
2.3.3 MDF JPX-202/3219 (Hawaii)………………………….….15
2.3.4 Joint Cable Connectors……………………………………16
2.3.5 MDF Faults, Detection and Checking…………………….16
2.3.6 Connection in Exchange…………………………………..17
2.3.7 Voltage and Current at MDF……………………………...17
2.3.8 New Telephone Connection………….…………………....17
2.4 DSL(Digital Subscriber Line)……………………...........................18
2.4.1 DSL Introduction………………...…………………….….18
2.4.2 Types of DSL……………………………………………...18
2.4.3 DSL Technologies Speed and… distance Chart………......18
2.4.4 ADSL Basic Architecture………………………….............18
2.4.5 DSL Modem……………………………………………….18
2.4.6 Digital Subscriber Line Access Multiplexer…...……..……19
2.4.7 BRAS……………………………………………………...20
2.4.8 Relation b/w DSL modem, DSLAM and BRAS…….…...20
2.4.9 Line Quality testing (meter reading for 2MB DSL)……....20
2.4.10 Difference b/w ADSL & DSL……………………….…..20
Part 3: SWOT Analysis….……………………………………….…….21
3.1Strengths……………………………………………….……21
3.2Weaknesses……………………………………………..…...21
3.3Opportunities…………………………………………..….....21
3.4Threats………………………………………………….........21
Part 4: Findings and Recommendations ………...………..…..……... 22
4.1 Findings…………………………..…………..………...…. 22
4.2 Recommendations…………………..…………...…..……. 22

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Introduction
Every year, many final year undergraduate students across Pakistan take part in summer internships
organized and supervised by various organizations in the country.
This document presents an internship report at PTCL (Pakistan Telecommunications limited). A brief
history and information of the organization is also included in the report.
Background
The company traces its origin from the Posts and Telegraph department established in 1947. It was later
renamed Pakistan Telegraph and Telephone department in 1962. In the early 90’s it became Pakistan
Telecom Corporation. PTCL became a public listed company in 1996. Etisalat acquired 26% PTCL shares
in 2006.
PTCL headquarters is located in Sector G-8/4, Islamabad, and has over ten regional headquarters throughout
the country. Dr. Daniel Ritz is the current President and CEO of the company.
Today PTCL is the largest fixed line telecommunications service provider in the country. PTCL services
include Landline and Wireless Telephony, Broadband and 3G internet, IPTV, Home security (I Sentry).
Every year PTCL offers paid and non-paid internships to university students. Engineering and computer
science students usually work in the Networks and Operation division. There are many departments under
this division.
The duration of this internship was 6 weeks, from 3Aug, 2016 to 16Sep,2016. The internship was in the
following departments:
 Transmission (2 Weeks)
 Switching (1 Week)
 MDF (1 Week)
 DSL (2 Weeks)

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2.1 TRANSMISSION
Transmission (abbreviation: Tx) is the process of sending and propagating an analogue or digital
information signal over a physical point-to-point or point-to-multipoint transmission medium, either wired,
optical fiber or wireless.
Transmission Technology
Transmission technologies and schemes typically refer to physical layer protocol duties such as modulation,
demodulation, line coding, equalization, error control, bit synchronization and multiplexing, but the term
may also involve higher-layer protocol duties, for example, digitizing an analog message signal, and source
coding (compression). Transmission of a digital message, or of a digitized analog signal, is known as data
transmission or digital communication. One transmission is the sending of a signal with limited duration, for
example a block or packet of data, a phone call, or an email.
Divisions of Transmission
DXX-II
ZNOC
OFC-I
DXX-II
Digital Cross Connect (DXX) is a state-of-the-art communication technology over Optical Fiber. Fast and
reliable data communication can be provided using this technology from 6.4 kbps to several Mbps. Optical
Fiber streams are terminated on Digital Cross Connect nodes and data connectivity is provided to customer’s
premises using line cards (2B1Q, V.35 DCC, DINIC, 27 LC3, 28 LC etc.) and DTUs (Data Terminating
Unit). Whole DXX network is monitored and controlled by Sun based Network Management System
(NMS).
Digital Cross Connect (DXX) is a state-of-the-art communication technology over Optical Fiber. Fast and
reliable data communication can be provided using this technology from 6.4 kbps to several Mbps. Optical
Fiber streams are terminated on Digital Cross Connect nodes and data connectivity is provided to customer’s
premises using line cards (2B1Q, V.35 DCC, DINIC, 27 LC3, 28 LC etc.) and DTUs (Data Terminating
Unit). Whole DXX network is monitored and controlled by Sun based Network Management System
(NMS).
The Digital Cross Connect (DXX) system is deployed in the full mesh configuration. The transmission
medium is Fiber Optic. Fiber Optic is the most reliable transmission medium for long haul communications.
Similarly it offers low transmission delays. This enables the customers to set up virtual private network at
very affordable prices. The central nodes of the network are made up of the 3630 Digital Cross Connect
switches from Alcatel, which are deployed at the Digital Transit Exchanges in all the cities. The 3630
Digital Cross Connect switches at each Digital Transit Exchange are then connected with the 3630
Multiplexers. Another important feature of the DXX is that Frame Relay can be employed in the existing
DXX network using FRE and FRS cards in Alcatel 3630 nodes.
Medias of Data Transmission
 Dial Up.
 ISDN (BRI).

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 ISDN (PRI).
 Digital Cross Connect (DXX).
 Digital Subscriber Line (XDSL).
 Optical Fiber Access Network (OFAN).
Dial UP
A component in Windows 95 and Windows 98 that enables you to connect your computer to a network via a
“modem”
2.1.1 ISDN
The Integrated Services Digital Network (ISDN) is a set of international standards for access to advanced,
all-digital public telecommunications networks. ISDN has three elements
I. Integrated Services
II. Digital
III. Network
Integrated Services
 Voice.
 Video.
 Image.
 Data.
 Mixed media at a number of standard
 Data rates
Digital
 Digital terminal equipment.
 Digital local loops.
 Digital trunks.
 Digital switching.
Network
 WLAN - Wireless Local Area Network
 WAN - Wide Area Network
 MAN - Metropolitan Area Network
 SAN - Storage Area Network, System Area Network, Server Area Network, or
 sometimes Small Area Network
 CAN - Campus Area Network, Controller Area Network, or sometimes Cluster Area
 Network
 PAN - Personal Area Network
 DAN - Desk Area Network
ISDN (BRI)
 The backup of DXX is ISDN/BRI. BRI stands for Basic Rate Interface.
 Its maximum rate is 128 KBps.
ISDN (PRI)
 It is use for Broadband Services. PRI stands for Primary Rate Interface.

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 Its maximum rate is 64 KBps.
Digital Cross Connect (DXX)
 The DXX provides a complete networking solution to the network operators with the following
benefits:
 Efficient utilization of existing transmission bandwidth.
 Powerful NMS to manage large networks.
 The best flexibility for networking.
 Manageability.
 Expandability.
 Higher service quality and hence higher customer satisfaction
 Super rate: Multiplexing of = > 64 K bits
2.1.2 ZNOC (Zonal Network Operation Center)
PTCL is a leading provider of telecom voice and data services within Pakistan. As part of its continuing
infrastructure developments, PTCL has embarked upon a major investment program in the Network
Operations Center (NOC). The purpose of NOC is to control, monitor and manage the entire PTCL network;
to enhance and optimize network management through a transparent and centralized platform and to create a
highly available, adaptable and fault resilient network that can meet market demand and offer customer
satisfaction. Through the NOC, PTCL has been able to address those issues with a complete convergence of
the entire network on a single platform.
There are three types of medias/carrier are used in Pakistan by
PTCL.
 Copper
 WLL (Wireless Local Loop)
 Optical Fiber
Using Copper as media of transferring of data, there is a local exchange (LE), the setup of LE is installed on
ground floor and the data is transferred from MDF (Main Distribution Frame); from the front side we access
via cable while back side is switching box.
Benefits
Proactive identification and resolution faults of through Real-time Network Monitoring & status visibility.
Increase network availability through Enhanced Quality of Service and centralized performance statistics
and reporting mechanism.
Increased Accountability and Transparency through escalation policies, work orders and maintenance of
secure activity logs.
OFC-I (Optical Fiber)
An optical fiber (or optical filer) is a flexible, transparent fiber made of extruded glass (silica) or plastic,
slightly thicker than a human hair. It can function as a waveguide, or “light pipe”, to transmit light between
the two ends of the fiber. The field of applied science and engineering concerned with the design and
application of optical fibers is known as fiber optics. Optical fibers are widely used in fiber-optic
communications, where they permit transmission over longer distances and at higher bandwidths (data rates)
than wire cables. Fibres are used instead of metal wires because signals travel along them with less loss and
are also immune to electromagnetic interference. Fibers are also used for illumination, and are wrapped in
bundles so that they may be used to carry images, thus allowing viewing in confined spaces. Specially
designed fibers are used for a variety of other applications, including sensors and fiber lasers.

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Types of optical fiber cable
Optical fiber cable is available in three forms which are
I. Slotted core cable
II. Loose tube cable
III. Loose tube slotted core cable
Main Application of the optical fiber cables
o Public and private telecommunication lines
o Computer network (LAN, WAN )
o Television distribution network (CATV)
o Military network
o Control, remote control & signalizing network
o Video supervision lines
Advantages of the optical fiber cables
Optical fiber cables are not affected by any interference originated from energy transmission lines. Radio
waves and cross talk between the fibers does not exist. No special protection is necessary.
1. Non Conductivity
No grounding is necessary because of metal free cable.
2. Large Wide bandwidth
Suitable for high speed. Wide-band, telecommunication lines.
3. Low Loss:
Because of Low few or no amplifiers are necessary.
4. Very Light Weight
The smallest cables can be designed and manufactured therefore reduce pulling strength and reduce laying
cost.
5. Economic
The most economical solution for the simultaneous transmission of several multichannel users.
6. Low Attenuation
7. No Cross Talk
8. Many channel Capacity
9. Easy Installation
Optical fiber cable used in Pakistan
 Olex cable (18 fiber slotted core number of slot 6)
 Fujikura cable (18 fiber slotted core number slot 10)
 Siemen cable (12 fiber loose tube)
 LT Engineering cable (18, 12, 6 fiber loose tube with slotted core)
Ring Topology

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A ring network is a network topology in which each node connects to exactly two other nodes, forming a
single continuous pathway for signals through each node - a ring. Data travel from node to node, with each
node along the way handling every packet.
Because a ring topology provides only one pathway between any two nodes, ring networks may be disrupted
by the failure of a single link. A node failure or cable break might isolate every node attached to the ring. In
response, some ring networks add a "counter-rotating ring" (C-Ring) to form a redundant topology: in the
event of a break, data are wrapped back onto the complementary ring before reaching the end of the cable,
maintaining a path to every node along the resulting C-Ring. Such "dual ring" networks include Spatial
Reuse Protocol, Fiber Distributed Data Interface (FDDI), Resilient Packet Ring

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2.2 SWITCHING
PTCL is a leading telecom company of Pakistan and it is accordingly increasing its technologies as the global
communication is growing larger to enter Pakistan into the current flow, PTCL is shifting its old copper wire land line
connections (slow speed) to new optical fiber wire connections (very high speed) that operate on laser to transfer data
at speed of light.
Technical Requirements of Packet Transport Network
1. TECHNICAL REQUIREMENTS
o 1.1.PTCL intends to install and deploy Packet based transport solution in its network.
o 1.2. The objective of these specifications is to define and fix standards for equipment/services required for
Packet based transport solution. The proposed solution shall consist of different capacity nodes, Network
Management System (NMS), auto service provisioning systems and other network components.
o 1.3. The services shall include NGN VoIP, PTP (Point-to-Point), PTMP (Point-to-Multipoint), Uni-cast,
Multi-cast, active Ethernet, CDMA WLL VoIP, Wimax, IP Centrex, Internet services, Triple play services
(voice, video, data), VoD, DSL, VPN, VPLS and other Multi Protocol Label Switching (MPLS-TP) services
etc.
o 1.4. The offered solution shall be support ring, hub-and-spoke (star), full and partial mesh topology.
o 1.5. The network shall be deployed in hierarchy having core, distribution (aggregation) and access layers.
o 1.6.Following are the Architecture requirements:
o 1.6.1. Core Aggregation Metro Node (High End Node)
i). Minimum slots: 10
o ii). Slot capacity: Minimum 100 Gbps
o iii). Chassis backplane capacity: Minimum 2 Tbps
o 1.6.2. Core Metro Node (Medium End Node)
o i).Minimum slots: 6
o ii).Slot capacity: Minimum 100 Gbps
o iii).Chassis backplane capacity: Minimum 1 Tbps
o 1.6.3.Access Metro Nodes
o i).Minimum slots: 2 or Fixed configuration
o ii).Uplink: Gbps (Multiple)
o iii).Uplink: 10 Gbps (Multiple)
o Note: The bidder shall quote for both uplink configurations
o 1.6.4. The offered equipment shall be modular and scalable. The bidder shall provide the basic/ultimate
capacity of the offered system.
o 1.7.Carrier-class reliability:
o 1.7.1. The offered system shall have redundant processors/ control units and fans.
o 1.7.2. The offered system shall have redundant hot-swappable power supplies.
o 1.7.3. Key modules including system control units and power supply shall adopt 1:1 mode backup. The high
reliability shall be ensured through the hitless protection. It shall be highly reliable with high figures of
MTBF.
o 1.8.Large capacity and high performance:
o 1.8.1. The offered system shall support non-blocking switching capability and packet forwarding capability
shall be sufficient to meet the requirements.
o 1.8.2. The offered system shall have Port-based and MAC-based VLAN support.
o 1.8.3. The bidder shall mention the values of Switching capability, Packet Forwarding Rate, L3 Route Entries,
L2 MAC addresses and number of VLANs supported.
o 1.9. The offered system shall have the following attributes as per MEF:
o i).Standardized Services
o ii).Scalability
o iii).Reliability
o iv). QoS

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o v).Service Management
o 1.10. The offered system shall support the following services:
o i).Data
o ii).Video
o iii).Voice
o iv).MPLS Layer 2 VPNs (end to end)
o v).
o vi).Ethernet
o vii).E-Line (EPL, VPL, Ethernet Internet Access (EIA), IP VPNs, etc.)
o viii).E-LAN (Multipoint L2 VPN, transparent LAN Services, Multicast networks)
o ix).E-Tree (Point to multi Point)
o x).Ethernet over MPLS (EoMPLS)
o xi).Ethernet: Q-in-Q, MAC-in-MAC, and MPLS TE
o 1.10.1. The offered solution shall be used to:
o i). Deliver L2 VPN services through existing service activator/provisioning system to:
o a. Ethernet to the home (ETTH)
o b. Ethernet to the business (ETTB)
o c. Ethernet between offices
o d. Existing DSLAM aggregation via MPLS core deployments based on MPLS VPN’s
o ii).Deliver Converged data via MPLS VPN’s, voice via MPLS VPN’s and video via L2 or IP or MVPN P2MP
LSP (Triple-play) services based on MPLS VPN’s on 2*10GE Broadband Network Core enable with RSVP-
TE and Diffuser TE.
o iii).Redundancy solution for DSLAM aggregation with VRRP or Multi chassis cluster solution
o iv).Backhauling different traffic types including CDMA and upcoming LTE and GPON technologies
o 1.10.2. The offered system shall implement the port-/application-/flow-based bandwidth control mode. The
solution shall inter-work with MPLS VPN service of devices from other mainstream vendors.
o 1.11. High port density with full duplex processing power and wire speed routing and switching.
o 1.11.1. The offered system shall support the following Interfaces:
o i). 100BASE-FX/1000BASE-X (SFP).
o ii). 10GE
o 1.11.2. PTCL has planned to transform SDH based metro network to IP based network in phased manner.
Bidders to state whether the support of following interfaces is available in their
o Offered solution?
o i).STM1
o ii).STM4
o iii).STM16
o iv).STM64
o 1.11.2.1. If support of above interfaces is available, bidder to state how they plan to implement.
o 1.11.2.2. If support of above interfaces is not available, bidder to state how this TDM interfaces, if required,
can be transported over Metro Ethernet network
o 1.11.3. Optical/electrical interfaces support is required.
o 1.12.Enhanced QoS and Synchronization support:
o 1.12.1. The offered system shall have MPLS, QoS, Multicast and IPv6 features providing Gigabit Ethernet
access for both fiber and copper deployments. The offered system shall have QoS features including Layer 2
QoS 802.1p, HQoS, DSCP/IP Precedence trust and marking.
o 1.12.2. The offered system shall have support for Time-based QoS, Profile-based QoS, Policy-based QoS,
Layer 2 and Layer 3 QoS facilitating tiered Ethernet service offerings through rate limiting and traffic
shaping.
o 1.12.3. The offered system shall provide mechanisms such as hardware-based flow classification, accounting,
multicast and rate restriction etc.
o 1.12.4. Priority queuing, flow metering and policing (IEEE 802.1Q), congestion notification (IEEE 802.1au),
drop precedence (802.1ad), precision time synchronization (IEEE 1588 latest version), and packet network
frequency synchronization (ITU-T G.8261), or their latest versions.
o 1.13.Traffic Control Functions:
o 1.13.1. The offered system shall have Hierarchical QoS feature.
o 1.14.Network Management:

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o 1.14.1. The offered system shall have different Management options including CLI, GUI and web based
Management.
o 1.14.2. The offered system shall have in-band as well as out-of-band management capability via Telnet mode
(CLI) and SNMP (GUI), in addition to having FCAPS capability.
o 1.14.3. The offered system shall support Ethernet OAM (802.1ag, 802.3ah and E-LMI).
o 1.14.4. The offered system shall be possible to export Performance and Fault data to third-party management
systems including HP OpenView and Computer Associates Unicenter software, to provide a complete
consolidated view of network operations.
o 1.15.Ethernet OAM and Management support:
o 1.15.1. IEEE802.1ag (Connectivity Fault Management (CFM), ITU-T Recommendation Y.1731 (OAM
functions and mechanisms for Ethernet based networks), Restoration technologies (e.g., xSTP, IEEE 802.1aq),
ITU-T Recommendation G.8031 (Ethernet linear protection switching), G.8032 (Ethernet ring protection
switching) or equivalent.
o 1.15.2. MPLS OAM support.
Switching Technology
There are 7 different kinds of switching technologies currently operational in PTCL network.
 Alcatel
 Siemens
 NEC
 Ericson
 Huawei
 J.S telecom
 ZTE
 With these different switching technologies PTCL is running its huge network and providing
different communication facilities to its customers.
2.3.1 Modes of Switching
There are two modes of switching.
 Circuit Switching
 Packet Switching
Circuit switching includes mobile services. It is not reliable as compared to packet switching. Packet
switching includes mail via internet, mobile messages etc. It is reliable mode of switching.
PTCL Corporate Services
 DXX
 Non DXX
 ISDN/PRI
 ISDN/BRI
 E1/E3 Connectivity
 MPLS
 EDSLBDSL
 PIE Connectivity
 Web Browser
 Tele presence
 DSR links
Launch Of IN Platform
 To augment the capacity and introduce additional value added services a new Intelligent
Network (IN) Platform was launched in October 2003.This platform has higher capacity
for prepaid calling cards and provision for introduction of new services.

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 To further support the launch of new services the optical fiber junction access network
has been in implementation phase. This system further supports the upcoming project of PTCL WLL
(wireless local loop), Broad Band Services & IPTV. Network Operation Center (NOC) (Pakistan
Telecommunication Company Limited, Oct-Dec 2008, pp. 21-22)
Pakistan Telecommunication Company Limited (PTCL) is a prime provider of telecom voice and data
services within Pakistan. As Part of its ongoing infrastructure development, PTCL has embarked on a major
investment program in a Network Operations Center (NOC).
Fig. NOC application launched
The purpose of NOC is:
ü To control, monitor and manage the entire PTCL Network
ü To enhance and optimize Network Management through a transparent and centralized platform
ü To create a highly available, adaptable and fault resilient network that can meet the market demand and
provide customer satisfaction
Due to the absence of a NOC, PTCL currently faces serious operational challenges:
ü Since there is no centralized network management, fault resolution is ad hoc and inefficient, service
restoration takes a long time
ü There is no mechanism for root cause analysis
Through the NOC PTCL have been able to address these issues with:
ü A complete convergence of entire Network on a single platform
ü Proactive identification and resolution of faults through:
§ Real-time Network Monitoring & status visibility.
ü PTCL have been able to increase network availability through:
§ Enhanced Quality of Service and centralized performance statistics and reporting mechanism.
ü Increased Accountability and Transparency
§ Through escalation policies, work orders and maintenance of secure
activity logs
2.3.2 NOC in PTCL
The main NOC is located in the CDDT Building, Islamabad. There are 3 regional NOCs
in Lahore, RWP and Karachi respectively. Disaster Recovery shall be done in Karachi.
Network Domains that have been integrated into NOC:
WLL, IN, Signaling, TDM/, Switching, OFAN, TXM, DXX, PIE, NGN and
Triple Play

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2.3 MDF (Main Distribution Frame)
2.3.1 PTCL Architecture:
 PTCL Exchange
The Exchange is the building where the local exchange switch resides. A CO’s switch may serve telephone service
subscriber in a very narrow geographic area such as a single large building.
 Distribution Point (DP)
From user to Distribution Point Drop Wire is used. And low- medium density copper cable (2-300 pairs) from DP to
Distribution Frame. New building can be built and DPs are used to provide them connection Instead to direct
connection to Exchange.
 Distribution Frames (DF)
Distribution fames surround the CO. They are high density copper cable (50-1500 pair) Primary Cable. Usually all
connection to a distribution frame are copper. It allows the telephone company to use High Density Copper Cabling.
 Main Distribution Frames (MDF)
MDFs are distribution frames that have some smart switching in them. Usually, this equipment has been placed to
provide the facility of DSL for access to use Internet. With the help of DSLAM Internet is enabling in MDFs for
particular user.
2.3.2 Networks
There are two types of networks
i. Internal network: It is consisted of connections of Exchange to MDF and MDF to cabinet.
ii. External network: It is consisted of connections of cabinet to DP and Drop line to subscriber.
Cable system:
There are three types of cables are use for the transmission and receiving of data transmission
i. Main Cable System (Primary Cable):

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It is having cables from exchange to main distribution points, e.g. cabinets or subscriber’s distribution frame in
multi-story buildings. It is highly density copper cable. Primary cable has 300/400 pairs while Secondary cable
has 600/800 pairs.
600 pair’s Primary cables
ii. Distribution Cables System (Secondary Cable):
This is having cables from main distribution point (e.g. cabinets) to subscriber distribution points e.g. DP boxes.
Secondary Cable Drop Wire
Two types of cables are used in the distribution cable system.
a. Polyethylene insulated copper cable having diameter of 0.4mm or 0.6mm but this PTCL exchange is using
cable having diameter of 0.4mm. It is low density copper cable. 0.4mm cable is used b/c it is easily joinable
and is cheap. 0.6 mm cable is not b/c it is difficult to joint and costly.
b. OFC (optical Fiber cable) is mostly used in Islamabad and Lahore. But it is not used mostly in Pakistan b/c it
need regular power supply but there is load shading issues so that’s way it is not. But OFC can transmit more
data than copper cable. As 1 Fiber optics can support 7890 channels. It transmits data with the speed of light.
2.3.3 MDF JPX-202/3219 (Hawaii):
MDF has two sides
i. Inside
ii. Outside
Inside connects the MDF to required switching Exchange NGN while outside connects the MDF to the cabinet.
And inside and outside of the MDF are connected to each other through jumper wire.
Inside of MDF:
Inside of the MDF is consisted of NEs which has one pair of jumping wire (Switching board cable). The
connection b/w these wire is horizontally connected by punching tool. PG (permanent Glow) is inserted b/w the NEs
to block or disconnection some subscriber from switching exchange and cabinet.
Outside of MDF:
Outside of the MDF is consisted of the multiple racks of 15 tags having 100 fuses in one vertical. Fuses show
the subscriber connections. Outside of the MDF is connected to the inside of the MDF by jumping wire. Outside of the
MDF have two wires which have vertically connection.
MDF belonging to which switching room:
This MDF belongs to switching exchange of NGN Exchange.
Local Exchange:
MDF room has its own local exchange which handles the telephone numbers within this PTCL exchange. I.e.
switching room, Alcatel, MDF, officer telephones numbers, war room telephone number and optical fiber telephone
numbers etc.
Exchange Cabinet
Cabinet SubscriberDistribution
point (DP)

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SNR of Cable:
 S/N is mostly used to measure how much a signal has been corrupted by noise.
 Mostly SNR is checked before providing DSL connection.
 SNR should be b/w 1 to 9 for telephone and DSL.
 No of joints in a cable should be less.
 The higher the ratio, the greater the resulting clarity.
2.3.4 Joint Cable Connectors:
1 U-Y connector:
They enable connecting wires without the need of isolation stripping. They are filled with gel, which
protects wires from corrosion. UY connectors should be used for wires with external coat up to 1.52mm in
diameter and 0.4-0.7 wire diameter. The Sealant used in the connector provides the most effective water &
moisture protection. It connects more than 25 pair of solid copper wires at one time.
2.3.5 MDF Faults, Detection and Checking:
Faults occurring in primary/ secondary cable are due to following reasons:-
1. Jumper Loosing
2. Jumper Break
3. Contact Fault
4. Faulty DSL Port
5. Switch room Fault
6. Fault in Fuse
i. Drop line cable is checked by fault locator if there is no fault. Then fault may be in DP.
ii. DP connection is checked by checking dialing tone on the telephone. If there is dialing tone then there is
no fault. If there is not dialing tone then the DP connection has fault. Then new connection in DP is
assigned by punching tool. If still now the telephone is not in working state. Then fault may be cabinet.
iii. Secondary cable is checked by fault locator if there is no fault then cabinet connection has fault. Then
fault may in cabinet.
iv. The dialing tone is checked in cabinet if there is dialing tone then there is no fault. If there is no dialing
tone the fault may be in MDF.
v. MDF required vertical cable pair connection is checked by dialing tone. If there is no dialing tone then
vertical cable pair is changed. If there is the dialing tone then there is no fault so the fault will be in
switching exchange.
vi. Switching exchange power supply, cards etc. is checked and changed. Then card is sending to be
repaired in required manufacturing company

17. INTERNSHIP REPORT
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2.3.6 Connection in Exchange:
Home
2.3.7 Voltage and Current at MDF:
ON Hook Off Hook When bell is ringing When bell is not ringing
Voltage 49 v 13.6 v 53.1 vDC /139 vAC 53.1 vDC /116.2 vAC
Current 0.130 mA 48mA 0.9 mA 0.9 mA
2.3.8 New Telephone Connection:
Document required for new connection:
I. NIC Copy
II. Property Deal (Rent Agreement+ NIC of House owner if a person is living on Rent)
III. Demand Notice(With 3 Months line rent in Advance)
Distribution
point
Vertical
side
DSLAM
in MDF
NE side
of MDF
i
o
cabin
Exchange
Switching
room
N.E
(MDF)
Cabinet Distribution Frame
DSLAM

18. INTERNSHIP REPORT
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2.4 DSL (Digital Subscriber Line):
2.4.1DSL Introduction:
DSL is a family of technologies that provides digital data transmission over the wires of a local telephone network.
DSL originally stood for digital subscriber loop. DSL service is delivered simultaneously with regular telephone on
the same telephone line. This is possible because DSL uses a higher frequency. These frequency bands are
subsequently separated by filtering.
The data throughput of consumer DSL services typically ranges from 256 Kbit/s to 40 Mbit/s in the direction to the
customer (downstream), depending on DSL technology, line conditions, and service-level implementation.
2.4.2Types of DSL:
 ADSL ( Asymmetric digital subscriber Line (Most popular))
 HDSL (High Bit rate digital subscriber Line0
 IDSL (ISDN based digital subscriber Line)
 VDSL( Very High Speed digital subscriber Line)
2.4.3DSL Technologies Speed and distance Chart:
The chart below provides a comparison of the various DSL technologies
DSL Type Max. Send Speed Max. Received Speed Max. Distance
ADSL 800 kbps 8 Mbps 18,000 ft (5,500 m)
HDSL 1.54 Mbps 1.54 Mbps 12,000 ft (3,650 m)
IDSL 144 kbps 144 kbps 35,000 ft (10,700 m)
VDSL 16 Mbps 52 Mbps 4,000 ft (1,200 m)
2.4.4ADSL Basic Architecture:
2.4.5DSL Modem:
A Digital Subscriber Line (DSL) modem is a device used to connect a computer or router to a telephone circuit that
has Digital Subscriber Line service configured. Like other modems, it is a type of transceiver. It is also called a DSL
Transceiver or ATU-R (for ADSL Transceiver Unit-Remote). DSL modem working as a bridge does not need an IP
address; it may have one assigned for management purposes. A DSL modem modulates high-frequency tones for
transmission to a Digital Subscriber Line Access Multiplexer (DSLAM), and receives and demodulates them from the
DSLAM. A single telephone line can be used for simultaneous voice and data with a DSL modem whereas a voice-
band modem precludes simultaneous voice traffic. Most DSL modems are external to the computer and wired to the
computer's Ethernet port, or occasionally its USB port. Internal DSL modems with PCI interface are rare but available.

19. INTERNSHIP REPORT
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DSL modems use frequencies from 25 kHz to above 1MHz in order not to interfere with voice service. Voice-band
modems use the same frequency spectrum as ordinary telephones, and will interfere with voice service - it is usually
impossible to make a telephone call on a line which is being used by a voice-band modem.
Used Equipment:
DSL Modem
SN=E29EB6D14870
Power= 12v= 500mA
Date=Jun 2011
ZTE Corporation
ADSL CPE
ZXDSL 83IC11
Made in china
ADSL Splitter
SP-206
Rosette has four cables blue,
yellow, black and red.
Connection:
Phone
DSL Modem
PC1 PC2 PC3 PC4
2.4.6Digital Subscriber Line Access Multiplexer:
The Digital Subscriber Line Access Multiplexer or DSLAM is a mechanism at a phone company’s central location
that links many customer DSL connections to a single high speed ATM line. It takes connections from many
customers and aggregated them onto single high capacity connection to the internet. They are generally flexible and
able to support multiple types of DSL in a single central office and different varieties of protocol and modulation. It
may provide additional functions including routing or dynamic IP address assignment for customers.
DSLAM Architecture:
DSLAM shelf contain card and each card contain 64 connections and so a complete shelf contain that contain 14 cards
would have 896 connections/subscribers.
Rosette ADSL
splitter
On/off
Power
LAN1 ADSL MODEM
LAN2
LAN3
LAN4

20. INTERNSHIP REPORT
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2.4.7 BRAS (Broadband Remote Access Server):
The Broadband Remote Access Server (B-RAS) is a key component of DSL broadband access networks that serves as
an aggregation point for subscriber traffic (IP, PPP and ATM) and provides session termination (PPPoX, RFC 1483)
and subscriber management functions such as authentication, authorization, accounting (AAA), and IP address
assignment.
Triggered by the new functional requirements that Triple-Play service delivery imposed on the DSL network
infrastructure and devices, modern B-RASs started to provide advanced services beyond traffic aggregation
2.4.8Relation b/w DSL modem, DSLAM and BRAS:
2.4.9 Line Quality testing (meter reading for 2MB DSL):
Uplink Downlink
DSL SNR 25.00 dB 42.30 dB
Line Attenuation 0.00dB 1.00dB
Actual Rate 636kbps 2557kbps
Maximum Rating 936kbps 28288kbps
2.4.10Difference b/w ADSL & DSL:
ADSL have different uplink and downlink rate while DSL have same uplink and downlink rate.

21. INTERNSHIP REPORT
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3 SWOT Analysis
3.1Strengths
 Exponential growth.
 Skilled Human Resource at low-cost.
 Access to Infrastructure – optical network and satellite links.
 Favorable policies (to some extent) and regulator.
 Strong international brand names.
3.2Weaknesses
 Quality of Service.
 Low revenue per user (ARPU).
 Customer retention.
 No clear strategic direction.
 Poor organizational structure.
 No research and development programs.
 Employee skill inconsistency.
 Very low employee morale.
3.3Opportunities
 Huge market size.
 Local handset manufacturing.
 Making technology accessible to all (e.g. broadband).
 Adopt latest technologies.
 Removal of international trade barriers.
 Adopting MVNO.
3.4Threats
 Recession in economy.
 Inconsistent and adhoc decisions from regulatory authorities.
 Political Instability, Security issues.
 Adverse shifts in trade policies of government.

22. INTERNSHIP REPORT
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FINDINGS AND RECOMMENDATIONS
In this chapter, we are going to discuss the findings and my view of recommendations which we faced and
thought during the internship. These findings and recommendations will help the organization to serve the
customers in a better way and will enhance their capabilities of performing earning and they will get the
high value than those upcoming competitors of it.
5.1 Findings
Below are some of the observations which we did during my internship duration. We mention it here for the
purpose to enhance the capabilities of the organization of my Area if these are considered by the managers.
They will also have an edge on the upcoming competitors of them and will not let them loose their potential
customers.
 No proper theory references on related topic for courses.
 The employees were not trained enough and were not having enough knowledge about the work
they were performing.
 Less educated staff reduces the performance growth of the department in general and of the
organization as a whole.
 Lack of time Punctuality of workers and employees.
 No full co-ordination with the other departments.
 No proper procedure of installing new connections due to which the complaints increase and also
some customers lose their confidence in the Broadband connections.
 Internees were performing all the travel.
 Lack of computer knowledge of well designated employees.
5.2 Recommendations
The number of trainee engineers should be increased by increasing the number of positions available
through the one year paid internship program. This way there will be enough engineers to train summer
internees. Internees should be given basic hands on training on the different hardware and software used by
the departments. Also tasks, such as making databases, should be assigned to every internee, not just a few.
And other recommendations are discuss below
 No doubt P.T.C.L having the monopoly in providing the Land-Line Telephone connection in
Pakistan and its playing its role magnificently. In current scenario P.T.C.L has increases its Revenue
quite dramatically and probably that as soon as this organization has become privatized it will
flourish its revenue in better manner.
 PTCL should immediately change its Finance upper level of hierarchy and should stream line in the
good manner.
 PTCL should also encourage the Billing On line system that each and every customer should have to
pay his/her bill on line basis..
 The image of PTCL being leading Telecom providing is not good in the eyes of common customer
especially there are lot of complaints about the including the bogus local calls in the monthly bills of
various customers. PTCL should also provide the detail of local calls made from any Land Line
Number which would be provided in Micro level to the customer.
 Should be decreased the over number of employees.
 Should be developing the training and development process of every employee.