Thesis sdh

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Chapter 1
Fundamental of Transmission

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1.1 Introduction to Telecommunication systems:
Telecommunication is an electronics transmission system which technology concern with
communicating from a distance. It includes mechanical communication and electrical
communication because telecommunications has evolved from a mechanical to an electrical
from using increasingly more sophisticated electrical systems. Many different
telecommunication networks have been interconnected into a continuously changing and
extremely complicated global system. Modern telecommunication systems capable of
transmitting telephone, cellular telephone, fax, data, radio, television signals can transmit
large volumes of information over long distances. The basic purpose of telecommunication
network is to transmit information in any form to another user of the network.
Figure 1.1: Branches of Telecommunication Networks.

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1.2 Telecommunication Networks:
A communication network is a collection of transmitters, receivers, and communication
channel that send messages to one another. Some digital communications networks contain
one or more router that work together to transmit information to the correct user. An analog
communications network consists of one or more switches that establish a connection
between two or more users. For both types of network, repeaters may be necessary to amplify
or recreate the signal when it is being transmitted over long distances. This is to combat
attenuation that can render the signal indistinguishable from the noise.
1.3 Transmission:
Transmission is the process of transporting information between end points of a system or
network. The end to end communication distance is often very long and there are many
electrical systems on the line. These systems, network elements such as exchanges, are
connected to the other elements with connections provided by the transmission. The basic
restrictions and requirements for transmission and the characteristics of various transmission
media and equipment used in the telecommunications core network. The transmission
systems for access network for high-data rate customer access to the network. Transmission
systems use for four basic media for information transfer from one point to another:
1. Copper cables, such as those used in LANs and telephone subscriber lines.
2. Optical fiber cables, such as high date rate transmission in telecommunication networks.
3. Radio waves, such as cellular telephone and satellite transmission.
4. Free space optics, such as infrared remote controllers.
In a telecommunication network, the transmission systems interconnect exchanges and taken
together, these transmission systems are called the transmission or transport network. The
transmissions needed for telecommunication through networks are: data, fixed or cellular
telephone services.
1.4 Elements of Transmission System:
The main elements of a communication system are shown in Figure 1. 2 The transducers,
such as a microphone or a TV camera that we need to convert an original signal to an
electrical form are omitted; unwanted disturbances such as electromagnetic interference.
Transmission channel capacity dependent on signal to noise ratio (SNR). It is reasonable to
expect that the frequency required for a given transmission should depend on the bandwidth.
The SNR ratio is important in the transmission of digital data because it sets the upper bound
on the achievable data rate. Shannon’s result is that the maximum channel capacity, in bits
per second, obeys the equation
C = B log2 (1+SNR)
Where, C=Channel capacity, B=Bandwidth, SNR=Signal to Noise Ratio

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Figure 1.2: Basic concept of transmission system.
1.5 Transmission media:
A transmission medium is a material substance solid, liquid or gas which can propagate
energy waves. For example, the transmission medium for sound received by the ears is
usually air, but solids and liquids may also act as transmission media for sound. The absence
of a material medium the vacuum of empty space can also be thought of as a
transmission medium for electromagnetic waves such as light and radio waves. While
material substance is not required for electromagnetic waves to propagate, such waves are
usually affected by the transmission media through which they pass, for instance by
absorption or by reflection or refractor at the interfaces between media. The term
transmission medium can also refer to the technical device which employs the material
substance to transmit or guide the waves. Thus an optical fiber or a copper cable can be
referred to as a transmission medium. Electromagnetic radiation can be transmitted through
an optical media, such as optical fiber or through twisted pair wires, coaxial cable or
dielectric--slab waveguides. It may also pass through any physical material which is
transparent to the specific wavelength, such as water, air, glass, or concrete. Sound is, by
definition, the vibration of matter, so it requires a physical medium for transmission, as
does other kinds of mechanical waves and heat energy. Historically, various a ether theories
were used in science and thought to be necessary to explain the transmission medium.
However, it is now known that electromagnetic waves do not require a physical transmission
medium, and so can travel through the "vacuum" of free space. Regions of the isolative
vacuum can become conductive for electrical conduction through the presence of free
electrons, holes, or ions
1.5.1 Twisted-pair cable:
A type of cable that consists of two independently insulated wires twisted around one
another. The use of two wires twisted together helps to reduce crosstalk and
electromagnetic induction. While twisted-pair cable is used by older telephone networks
and is the least expensive type of local-area network (LAN) cable, most networks contain
some twisted-pair cabling at some point along the network. Other types of cables used for
LANs include coaxial cables and fiber optic cables. Examples of transmission media include
twisted-pair cable, coaxial cable, and fiber optic cable figure1.3

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1.5.2 Coaxial cable:
A type of wire that consists of a center wire surrounded by insulation and then a
grounded shield of braided wire. The shield minimizes electrical and radio
frequency interference. Coaxial cabling is the primary type of cabling used by the
cable television industry and is also widely used for computer networks, such as
Ethernet . Although more expensive than standard telephone interference and can carry
much more data. wire, it is much less susceptible.
Figure 1.4: Coaxial cable/PCM cable
1.5.3 Fiber optics:
A technology that uses glass (or plastic) threads (fibers) to transmit data. A fiber optic
cable consists of a bundle of glass threads, each of which is capable of transmitting
messages modulated onto light waves.
Fiber optics has several advantages over traditional metal communications
lines:
Figure 1.3: Twisted-pair Cable

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Properties Twisted Pair Coaxial Cable Optic Fiber
Data rate/Bandwidth 4 Mbps 500 Mbps Up to 100 Gbps
Repeater Spacing 1-10Km 1-10Km 10-100Km
• Fiber optic cables have a much greater bandwidth than metal cables. This
means that they can carry more data.
• Fiber optic cables are less susceptible than metal cables to interference.
• Fiber optic cables are much thinner and lighter than metal wires.
• Data can be transmitted digitally (the natural form for computer data)
rather than analogically.
Figure 1.5: Optical fiber
The main disadvantage of fiber optics is that the cables are expensive to install. In
addition, they are more fragile than wire and are difficult to splice. Fiber optics is a
particularly popular technology for local-area networks. In addition, telephone
companies are steadily replacing traditional telephone lines with fiber optic cables. In the
future, almost all communications will employ fiber optics.
Table 1: Comparison of Twisted Pair, Coaxial Cable and Optic fiber

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Chapter 2
Terminologies in Communication Systems

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2.1 Modulation:
Modulation is a process where information signal modify different quantities (Amplitude,
Phase, Frequency) to send over a long distance. It is the process of encoding information
from a message source in a manner suitable for transmission. There are two types of
modulation. These are
a. Analog Modulation (AM)
b. Digital Modulation (DM)
2.1a Analog modulation (AM):
Data are modulated by a carrier frequency to produce an analog signal in a different
frequency band which can be utilized on an analog transmission system.
2.1.b Digital modulation (DM):
The digital modulation with analog carrier allows an improvement in signal to noise ratio as
compared to analog modulating schemes.
2.1.2 Frequency modulation (FM):
The process by which the instantaneous frequency of a carrier signal is varied in
accordance with the instantaneous amplitude of the modulating signal
2.1.3 Phase modulation (PM):
A modulating signal that can vary the phase of the carrier signal maintaining constant
values of amplitude and frequency. The total phase of the modulation carrier changes due to
the changes in the instantaneous phase of the carrier keeping the frequency of the carrier
signal constant.
2.2 Pulse Amplitude Modulation (PAM):
PAM is a form of signal modulation where the message information is encoded in
the amplitude of a series of signal pulses. Pulse-amplitude modulation is widely used in
base band transmission of digital data, with non-base band applications having been largely
superseded by pulse-code modulation (PCM). From the figure 2.1 the Sampling produces a
time discrete PAM signal reflecting the amplitude of the analogue signal, PAM signal is
quantized producing PCM code, and the Quantizing is the replacement of real value by the
closet integer.

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Figure 2.1: Sampling processing
2.5 Pulse-code modulation (PCM):
Pulse code modulation (PCM) is a digital representation of an analog signal where the
magnitude of the signal is sampled regularly at uniform intervals, then quantized to a
series of symbols in a numeric (usually binary) code. Line code which also called digital
base band modulation is a code chosen for use within a communications system for
transmission purposes. Line coding is often used for digital data transport. Line coding
consists of representing the digital signal to be transported by an amplitude- and time-
discrete signal that is optimally tuned for the specific properties of the physical channel.
Figure 2.2: Sampling and quantization

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2.3 Line coding:
Line code which also called digital base band modulation is a code chosen for use within a
communications system for transmission purposes. Line coding is often used for digital
data transport. Line coding consists of representing the digital signal to be transported by an
amplitude- and time- discrete signal that is optimally tuned for the specific properties of the
physical channel.
2.4 Uses of line coding:
Coding is used to enable base band transmission in fiber optic system, cable transmission,
data access and storage. In PCM links line coding is used to alleviate clock synchronization
at the receiver. Line coding can also be used Line for error detection.
Line codes should:
•Be immune to long strings of zeros that can lead to missing receiver clock
synchronization
•Contain zero long term averaged DC component
•Have minimum bandwidth.
2.5 Conversion of voice into digital signal:
The conversion of voice into digital signal is done from a simple bandwidth of human voice
which is show in the following:
• Voice Channel Bandwidth: 4 KHz
Sampling rate=8,000 samples/second
Nyquist Theorem: Sample rate=2x highest audible frequency (4 KHz)
• Sampling: 4 KHz * 2 = 8 KHz
• Quantizing: Each sample is given a certain value which is 8 bits wide.
So the resulting signal rate will be:
• Encoding: 8000bps * 8 = 64 kbps
E1 Level= 32 * 64 Kb/s = 2.048 Mb/s (FOR one E1)

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2.6 E1 Digital carrier systems:
The 8 bit PCM frames are the fundamental block for digital carrier system E1/T1. E1
carries signals at 2 Mbps (32 channels at 64Kbps, with 2 channels reserved for signaling
and controlling), versus the T1, which carries signals at 1.544 Mbps (24 channels at
64Kbps). European Postal and Telecommunication Administration (CEPT). It's the
equivalent of the North E1 and T1 lines may be interconnected for international use.
E1 (or E-1) is a European digital transmission format devised by the ITU-TS and given the
name by the Conference of American T-carrier system format. E2 through E5 are carriers in
increasing multiples of the E1 format.
The E1 signal format carries data at a rate of 2.048 million bits per second and can carry 32
channels of 64 Kbps each. E1 carries at a somewhat higher data rate than T-1 (which carries
1.544 million bits per second) because, unlike T-1, it does not do bit-robbing and all eight
bits per channel are used to code the signal. E1 and T-1 can be interconnected. Each E1
frame has time duration of 125 micro second. It consists of 30 eight bit PCM frames and 2
eight bit control frames
2.7 Synchronous Transfer Module (STM):
The basic digital structure of the SDH hierarchy is formed by the frame of the so- called
Synchronous Transport Module, first hierarchical level, indicated by the acronym STM-1.
Through a process of multiplexing and linking of the STM-1 octet, transport modules of
higher order are formed (STM-N).
2.8 STM-1 frame structure:
The STM frame consists of 9 rows, each containing 270 bytes . Each byte is
composed of 8 bits. The frame frequency (8 kHz) has been selected so that 1 byte of the
frame corresponds to the transmission capacity of a 64 kbit/s channel. The overall transport
capacity is:
STM-1 = 8 * (9 * 270) * (8 * 103) = 155.520 Mbps
a b c
a) Number of bits composing each byte
b) Overall number of bytes in each frame
c) Frame frequency
Each frame is composed of:
• One frame head, called SOH (section overhead), which occupies the first 9 bytes
of each row except the fourth and is used for transmission of service information.

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• A field of 261*9 bytes plus the first 9 bytes of the fourth row which represent the
administrative unit (AU-4). The AU carries the payload.
Figure 2.3: STM-1 Frame Structure

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Chapter 3
Transmission SDH Networks

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3.1 Services of SDH Transmission Networks link:
In telecommunications, transmission is the process of sending, propagating and
receiving an analogue or digital information signal over a physical point-to-point or
point-to-multipoint transmission medium, either wired or wireless.
In TELETALK the transmission network consist of the following major
transmission technologies:
1. Optical fiber communication link
2. Microwave communication link
Both optical fiber and microwave communication link support PDH and SDH link.
3.2 Plesiochronous Digital Hierarchy (PDH):
The Plesiochronous Digital Hierarchy (PDH) is a technology used in networks run in a
state where different parts of the network are nearly, but not quite perfectly, synchronized.
Telecommunications networks to transport large quantities of data over digital transport
equipment such as fiber optic and microwave radio systems. The term Plesiochronous is
derived from Greek plesios, meaning near, and chronos, time, and refers to the fact that PDH.
The higher-order multiplexers of PDH are allowed to operate according to their own
independent clock frequencies.
PDH allows transmission of data streams that are nominally running at the same rate, but
allowing some variation on the speed around a nominal rate. By analogy, any two watches
are nominally running at the same rate, clocking up 60 seconds every minute. However, there
is no link between watches to guarantee they run at exactly the same rate, and it is highly
likely that one is running slightly faster than the other.
Multiple data streams are not necessarily running at the same rate, some compensation has to
be introduced. The transmitting multiplexer combines the four data streams assuming that
they are running at their maximum allowed rate. This means that occasionally, (unless the
2 Mbit/s really is running at the maximum rate) the multiplexer will look for the next bit but
it will not have arrived. In this case, the multiplexer signals to the receiving multiplexer that a
bit is "missing". This allows the receiving multiplexer to correctly reconstruct the original
data for each of the four 2 Mbit/s data streams, and at the correct, different, plesiochronous
rates.
The basic data transfer rate is a data stream of 2048 kbit/s. For speech transmission, this is
broken down into thirty 64 kbit/s channels plus two 64 kbit/s channels used for signaling and
synchronization. Alternatively, the entire bandwidth may be used for non-speech purposes,
for example, data transmission.

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Figure 3.1: PDH (European Standard)
Table 2: Channel capacity of PDH
These E1 channel bits can either be transmitted by modulating a microwave carrier or
using optical links. PDH (Plesiochronous Digital Hierarchy) is a term used to refer to
microwave transmission links. They are not synchronized by one master clock; rather
locally generated clock pulses are used. Hence, the term PDH is used rather SDH
Signal Bit rate Channel
E1 2.048 Mbps 30-31
E2 8.448 Mbps 120-124
E3 34.368 Mbps 480-496
E4 139.264 Mbps 1920-1984

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3.3 Synchronous Digital Hierarchy (SDH):
PDH is typically being replaced by Synchronous Digital Hierarchy (SDH) or Synchronous
optical networking (SONET) equipment in most telecommunications networks. The SDH
standard was originally defined by the European Telecommunication Standards Institute
(ETSI), and is formalized as International Telecommunications Union (ITU) standards
G.707, G.783, G.784, and G.803. The SONET standard was defined by Telcordia and
American National Standards Institute (ANSI) standard T1.105.
Figure 3.2: ETSI Standard of SDH
Synchronous optical networking (SONET) and synchronous digital hierarchy (SDH) are
standardized multiplexing protocols that transfer multiple digital bit streams over optical fiber
using lasers or light-emitting diodes (LEDs). Lower data rates can also be transferred via an
electrical interface. The method was developed to replace the Plesiochronous Digital
Hierarchy (PDH) system for transporting larger amounts of telephone calls and data traffic
over the same fiber without synchronization problems

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Table 3: Channel capacity of SDH
3.4: Multiplexing:
Multiplexing is used when the total medium transmission capacity exceeds the channel’s one.
Whereas Channels are multiplexed for a better use of medium. Multiplexed is useful
for long-haul communications; trunks are fiber, coaxial, microwave high capacity links.
It has higher data rate transmission and it is cost- effective transmissions for a given
application over a given distance. It is used for transmitting multiple signals to share in
one medium; the medium must somehow be divided, giving each signal a portion of the total
bandwidth.
Figure 3.3: MUX and DEMUX
3.5 Multiplex techniques :
There are many techniques that are used of which three will be discus here, which are
Time Division Multiplexing, Frequency Division Multiplexing, and Wavelength
Division Multiplexing.
3.6 Time-Division Multiplexing (TDM):
TDM is a type of digital or analog multiplexing in which two or more signals or bit
streams are transferred apparently simultaneously as sub-channels in one
communication channel, but are physically taking turns on the channel. The time
domain is divided into several recurrent timeslots of fixed length, one for each sub-
channel. There are Three types of TDM which are Synchronous Digital Hierarchy
(SDH), The Plesiochronous Digital Hierarchy (PDH), and Asynchronous Time-
division Multiplexing (ATDM).
SDH Bit rate E1
STM-1 155.520 Mbps 63
STM-4 622.08 Mbps 252
STM-16 2488.32 Mbps 1088
STM-64 9953.28Mbps 4032

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Figure 3.4: Time Division Multiplexing.
The figure 3.4 multiplexer accepts input from attached devices in a round-robin fashion
and transmits the data in a never ending Pattern.
3.7 Frequency Division Multiplexing (FDM):
FDM is a form of signal multiplexing which involves assigning non-
overlapping frequency ranges to different signals or to each "user" of a medium. A
Number of signals carried simultaneously, each signal modulated onto a
different carrier frequency, which are separated for avoiding signals bandwidths
to overlap. Assignment of non-overlapping frequency ranges to each “user” or
signal on a medium. Thus, all signals are transmitted at the same time; each
using different frequencies.

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Figure 3.5: The multiplexer in the FDM accepts inputs and assigns
Frequencies to each device.
3.8 Wavelength-division multiplexing (WDM):
WDM is a technology which multiplexes multiple optical carrier signals on a single optical
fiberby using different wavelengths of laser light to carry different signals. This allows
for a multiplication in capacity, in addition to enabling bidirectional communications
over one strand of fiber. Different lasers transmit multiple signals at different
wavelengths. Each signal carried on the fiber can be transmitted at a different rate from the
other signals.
Figure 3.6: Wavelength-division multiplexing

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3.9 SDH Multiplexing:
It is very important to understand the SDH multiplexing hierarchy to truly understand and
appreciate SDH. Multiplexing follows a rigid hierarchy in SDH. From an extremely high-
level perspective, it is safe to say that low-level PDH signals are mapped to an SDH entity
known as a container (C). The C is mapped along with POH bytes to form another entity
known as a lower-order virtual container (VC). The lower-order VCs are aligned with
tributary unit (TU) pointers to form entities known as tributary units (TUs). The TUs are
multiplexed to form tributary unit groups (TUGs). The TUGs are further multiplexed to form
higher-order VCs. These higher-order VCs are aligned with fixed byte-stuffing and
administration units (AU) to form administration units (AUs). The AUs are further
multiplexed to form administrative unit groups (AUGs). The AUGs are finally multiplexed
along with RSOH and MSOH bytes to form the STM-N signal.
There are variations to the flow just described as you will notice in the subsequent discussion.
Before you read on, you need to understand a few simple terms. The multiplexing principles
of SDH use the following terms:
• Mapping— A process used when tributaries are adapted into VCs by adding
justification bits and POH information.
• Aligning— This process takes place when a pointer is included in a TU or an AU, to
allow the first byte of the VC to be located.
• Multiplexing— This process is used when multiple lower-order path layer signals are
adapted into a higher-order path signal, or when the higher-order path signals are
adapted into a multiplex section.
• Stuffing— As the tributary signals are multiplexed and aligned, some spare capacity
has been designed into the SDH frame to provide enough space for all the various
tributary rates. Therefore, at certain points in the multiplexing hierarchy, this space
capacity is filled with fixed stuffing bits that carry no information, but are required to
fill up the particular frame.
3.9.1 SDH Transport Systems:
1. SDH Frame and Multiplex Structure
a) STM-1 Frame (Section Overhead, Pointers, Virtual Containers
b) SDH Multiplex Hierarchy (STM-N, AU-3/4, VC-3/4, VC-1/2)
2. SDH Network Elements and Topologies
a) Terminal & Add/Drop Multiplexers, Digital Cross-Connects
b) Hub / Mesh / Ring Architectures
3. SDH Overhead information
a) Multiplex / Regenerator Section Overhead (MSOH / RSOH)
b) Higher / Lower Order path Overhead (VC-4/VC-3/VC-2/VC-1 POH)
3. SDH Management Function
a) Anomalies, Defects, Failures and Alarms
b) Fault / Performance and Configuration Management
4. SDH Automatic Protection Switching (APS)
a) 1+1, 1:1 and 1:N Protection
b) Multiplex Section Protection, K1/K2 Bytes, path Protection
5. SDH Timing and Synchronizations

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3.9.2 Frame and Multiples structure:
Figure 3.7: STM-1 (Synchronous transfer module) SDH frame structure
a) SDH Frame Structure
• A single SDH frame is called a Synchronous Transmission Module (STM-1).
Transmitted over duration of 125 µs, the frame consists of 2430 octets organized
as 9 rows of 270 octets each. A single octet in an SDH frame represents a 64 kbps
Channel (8 bits every 125 µs), several octets can be aggregated to form containers
for larger data rates.
b) SDH Section Overhead (SOH)
• A relatively large number of 72 octets in an STM-1 frame have been reserved for
various management and monitoring purposes. This so-called section overhead
(SOH) is further divided into a regenerator section overhead (RSOH) and multiplex
Section overhead (MSOH).
c) Administrative Unit (AU-4) and Virtual Container (VC-4)
• The actual payload carried in an STM-1 frame is encapsulated in an administrative
unit (AU-4). The AU-4 consists of a VC-4 virtual container comprising 261 columns
plus a 9 octet wide AU-4 pointer that points to the first octet of the VC-4 payload
container.

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d) AU-4 Pointer
• The SDH pointer mechanism is a very elegant way of multiplexing multiple data
containers without the need to align the containers to a common frame start.
Thus the frame buffers in SDH multiplexing equipment can be kept small and the
transmission delay due to buffering is minimized.
• The VC-4 container is allowed to float freely within the AU-4. The H1 and H2 pointer
bytes form a word with a range of 0 to 782 which indicates the offset, in three byte
increments, between the pointer and the first byte of the VC-4. If the offset has the
value 0 then the J1 byte of the VC-4 follows immediately after the H3 bytes of the
AU-4 pointer
3.9.3 SDH Multiplexing Hierarchy:
Figure 3.8: ETSI Branch SDH Multiplexing Hierarchy
3.9.4 SDH Network Element:
a) Digital Cross-Connect (DCS/DXC)
used in meshed networks
mainly STM-N interfaces
large switching matrix (1024 STM-1)
Wideband DCS: VC-12 granularity
Broadband DCS: AU-4 granularity
b) Add/Drop Multiplexer (ADM)
used in rings

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two STM-N line interfaces (East/West)
large number of tributary interfaces
STM-1, 140 / 34 / 2 Mbit/s
(equipped up to full ring capacity)
c) Terminal Multiplexer (TMX/PTE)
used as concentrator (hub)
STM-1/4 (redundant) line interface
mainly 2 Mbit/s tributary interfaces
3.9.5 SDH Transmission Multiplexing:
SDH multiplexing system provides a set of standard information structure levels, i.e. a set of
standard rate levels. The basic signal transmission structure level is a synchronous transfer
module ( STM-1) at a rate of 155Mb/s. Digital signal hierarchies of higher levels such as
622Mb/s (STM-4) and 2.5Gb/s (STM-16) can be formed by low-rate information modules
(e.g. STM-1) via byte interleaved multiplexing. The number of modules to be multiplexed is
a multiple of 4. For example, STM-4=4xSTM-1 and STM-16=4xSTM-4
Figure 3.9: SDH 4:1 Multiplexing

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3.9.6 PDH Multiplexing Method:
The set of standards that explains the higher order transmission rates is referred as the
PDH.As fast developments occur in the transmission systems, PDH multiplexing systems
become expensive and complex solutions due to some weak points. It is impossible to
remove a 2 Mb/s signal from a 140 Mb/s directly. Three multiplexing steps are required to
obtain a 2 Mb/s lower order signal from a 140 Mb/s higher order signal. The procedure is
shown in the Figure 3.10.
Figure 3.10: PDH Multiplexing
All other signals are asynchronous and require code rate justification for matching and
accepting clock difference. As PDH adopts asynchronous multiplexing method, the locations
of the low-rate signals are not regular nor fixed when they are multiplexed into higher-rate
signals. Adding/dropping low-rate signals to high-rate ones must go through many stages of
multiplexing and de-multiplexing, impairment to the signals during multiplexing/de-
multiplexing processes will increase and transmission performance will deteriorate. This is
unbearable in large capacity transmission. That's the reason why the transmission rate of
PDH system has not being improved further.

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Chapter 4
SDH Microwave Transmission Link

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4.1 Microwave communication:
i) A communication system that utilizes the radio frequency band spanning 2 to 60 GHz. As
per IEEE, electromagnetic waves between 30 and 300 GHz are called millimeter waves
(MMW) instead of microwaves as their wavelengths are about 1 to 10mm.
ii) Small capacity systems generally employ the frequencies less than 3 GHz while medium
and large capacity systems utilize frequencies ranging from 3 to 15 GHz. Frequencies > 15
GHz are essentially used for short-haul transmission.
iii) Microwave radio communication requires a clear line-of-sight (LOS) condition.
iv) Radio LOS takes into account the concept of Fresnel ellipsoids and their clearance
criteria.
4.2 Requirements of SDH Microwave:
SDH Digital Microwave Radio Links is a high-performance, low-cost, secure and reliable
transmission products.SDH Digital Microwave Radio Links includes Indoor unit (IDU),
Outdoor unit (ODU, the RF unit), antenna and all basic accessories.SDH Digital Microwave
Radio Links supply point-to-point radio connection in the telecommunications network,
which is widely used in enterprise access, interconnect base stations, emergency
communications, and community access and relay connecting link.SDH Digital Microwave
Radio Links (IDU) is designed for different RF Unit working in different RF frequency band
6/7/8/13/15/18 GHz. And the IDU used the same IF interface to connect to all these ODUs
through coaxial cable. Highlights of SDH Digital Microwave Radio Links.
a) RFU rack design, high performance and reliability
b) Frequency Range: 5.8GHz, 6~8GHz, 11GHz, 13 GHz, 15 GHz
c) Flexible Interface Capability: STM-1, STM-2 or IP
d) High-speed IP Interface at 32Mb/s
e) RS encoding, QPSK.
f) Frequency Agility and easy Tuning on site
g) System Redundancy mode 1+0 or 1+1 optional
h) Web browsers control on PC through Ethernet port
i) Low power consumption, low noise figure and high gain
4.3 Link budget Calculation:
Path loss equation used for MW (3-38 GHz)
A=92.5dB+20 log f+20 log D+aD
Where
A=free space loss
f=Frequency in GHz
D=Propagation distance
a=Attenuation due to to the air and water vapor in dB/km (Typically 0.1-0.4)
Where ATL… Transmission line losses and branching circuit losses on Rx and Tx side

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G … Antenna gain on Rx and Tx side
A Misc … Miscellaneous losses (e.g. antenna misalignment, Tx power variations.
4.4 Fading of Microwave:
Fade Margin is a difference between median received signal level, calculated from Power
Budget equation, and BER=10-3 threshold of the receiver system.
This difference has to account for stochastic propagation phenomena that can compromise
system reliability.
These phenomena are:
a) Attenuation due to rain.
b) Intersystem interference.
c) Multipath fading.
d) K-factor variation.
e) Ducting.
4.5 SDH Microwave STM-1 link:
STM-1 point to point Microwave which is used for long distance connectivity, where optical
fiber is not available. These long distance STM-1 which is usually 1+1 , Space Diversity
System is shown in Figure 4.1 . Hence the STM-1 Optical interface is connected to the IDU
(Indoor Unit) of the Microwave system. Tributary Unit (E1 and Ethernet) is connected to
Add Drop Multiplexer.
An add-drop multiplexer (ADM) is an important element of optical fiber networks. A
multiplexer combines, or multiplexes, several lower-bandwidth streams of data into a single
beam of light. An add-drop multiplexer is a multiplexer that has the capability to add one or
more lower-bandwidth signals to an existing high-bandwidth data stream and at the same
time can extract or drop other low-bandwidth signals, removing them from the stream and
redirecting them to some other network path. This is used as a local "on-ramp" and "off-
ramp" to the high-speed network. ADMs can be used both in long-haul core networks and in
shorter-distance "metro" networks, although the former are much more expensive due to the
difficulty of scaling the technology to the high data rates and Dense Wavelength
Multiplexing (DWDM) used for long-haul communications.

28
Figure 4.1: Architecture of SDH Microwave Link
4.6 IDU (Indoor unit):
IDU supports 63E1 tributaries on connected by SDH MUX. Modem and ODU is connected
by IF cable. Optical interface mux card is connected Optical mux metro-1000.Here is two
2TM-1 microwave SDH link. Ethernet to Ethernet cross connect two IDU .Controller card is
controlled the mux card and modem with -48V power controller. Modulation is support 128
QAM and Band frequency 6 GHz.
Figure 4.2: Indoor Unit (IDU main and Space diversity)

29
4.7 ODU (Outdoor unit) Frequency Bands 6 GHz:
The ODU is including a waveguide antenna port. Type-N female connector for the ODU
cable, a BNC female connector (with captive protection cap) for RSSI access and a
grounding stud. A remote ODU mounting kit is also available an option. These may be used
to connect an ODU to standard antenna, or to a dual-polarized antenna for co-channel link
operation. Where two to be connected to a single antenna for hot-standby or frequency
diversity configuration, a direct-mounting coupler is used. They are available for equal or
unequal loss operation. Equal loss is normally 3.5/3.5 dB. Unequal is nominally 1.5/6.5dB.
Figure 4.3: Outdoor Unit (ODU)
4.8 System Overview of SDH Microwave:
IDU ES supports Fast Ethernet to 200 Mbps to provide an uncomplicated and cost effective
alternative to fiber. Its Layer 2 switch supports four customer 10/100 base-T ports, two over-
air transport channels and comprehensive VLAN and QoS options. Data throughputs range
from 20 to 200 Mbps, and depending on throughput channel bandwidth ranges from 7 to 56
MHz, with modulation options from 16 to 128QAM. Link capacity may be fully assigned to
Ethernet traffic, or between Ethernet and up to 8 wayside E1/DS1 circuits. Capacity is
licensed. The base configuration supports 50 Mbps data throughputs with higher capacities to
200 Mbps obtained by requesting additional capacity upgrades at time of order or as field-
downloadable software licenses

30
4.9 Advantage of Microwave SDH link:
a) Add drop Multiplexing
b) High Bandwidth
c) Where do not installation optical fiber
d) Wireless backbone link
e) Relay systems
f) Redundancy optical SDH backbone link
g) Low cost from optical fiber
h) Maintenance rapidly
i) Free space point to point communication link
j) Remote login
4.10 Disadvantage Microwave SDH link:
a) Multipath Fading
b) Link fluctuation
c) More Bit error
d) LOS communication link
e) RSL threshold cross in bad weather
f) Limited channel
g) Propagation loss
h) Free space loss
i) Noise and interference
j) Time variation

31
Chapter 5
Optical Communication Link

32
5.1 Introduction to Optical fiber:
Optical communication systems are light wave systems that employ optical fibers for
information transmission. It uses high carrier frequencies (≈ 100THz) or STM-256 in the
visible or near-infrared region of the electromagnetic spectrum. It uses light wave technology.
Light wave technology together with microelectronics is a major factor in the advent of the
“information age”.
Table 4: Chart showing characteristics of optical communication systems during various
stages of development.
Generation Wavelength
(nm)
Date Bit rate
Gbps
Type of
fiber
Loss
(dB/Km
Repeater
Spacing
(Km)
I 800-900 1977 0.045 GI-MM 3 10
II 1300 1981 0.045 GI-MM 1 30
III 1300 At
present
2.5 SI-SM ≤0.5 40
IV 1550 At
present
≥10 Not
assigned
‹ 0.3 ≥100
5.2 Types of Optical Fiber:
The transmission medium of SDH optical transmission network is, of course, optical fiber.
Since single-mode fiber features big bandwidth, easy upgrading and expansion and cost
efficiency, it has been internationally recognized as the only transmission medium of SDH.
There are three transmission “region” in optical fiber transmission, which are suitable for the
following wavelength ranges respectively, i.e. 850nm, 6360nm and 6550nm.Of these, 850nm
region only applies to multi-mode transmission, and the regions used for single-mode
transmission are the 6360nm and 6550nm only.
Transmission distance of optical signals in optical fibers is affected by both dispersion and
loss. Dispersion will widen the digital pulses transmitted in optical fibers, causing inter-
symbol interference and deteriorating signal quality. Transmission system will stop
functioning when inter-symbol interference deteriorates transmission performance to a
certain degree (e.g 60-3
). Owing to loss, the power of optical signals transmitted in optical
fibers decrease with the increase of transmission distance, and the transmission system will
stop functioning when optical power declines to a certain degree.
To extend the transmission distance of the system, we usually reduce dispersion and
loss.6360nm optical transmission region is called zero-dispersion region, where the
transmission dispersion of optical signals is minimized, and 6550nm region is called low-loss
region, where the transmission attenuation of optical signal is minimized.

33
ITU-T specifies three common optical fibers, i.e. fibers respectively in compliance with
G.652 Specifications, G.653 Specifications and G.655 Specifications.G.652 fiber has the best
dispersion performance in 6360nm wavelength region and is also called fiber without
dispersion shift (i.e. zero-dispersion region is at 6360nm wavelength). It applies to two
wavelength areas: 6360nm and 6550nm. G.653 fiber, also called dispersion-shifted single-
mode fiber, refers to the single-mode fiber with best dispersion performance in 6550nm
wavelength region. It keeps low dispersion and loss in 6550nm wavelength region by shifting
zero dispersion from 6360nm to 6550nm wavelength via the distribution change of refractive
index inside the fiber, and it mainly applies to 6550nm working wavelength area. G.654 fiber
is also called fiber with low-loss in 6550nm wavelength region, with its zero-dispersion
remaining at 6360nm wavelength, and mainly works in 6550nm region for submarine fiber
communication that requires very long transmission distance of regenerator section.
5.3 Types of Optical Interfaces:
Optical interfaces, a unique part of synchronous cable digital line system. As it is
standardized, different NEs can be directly connected via optical fibers, thus dispensing with
optical/electrical conversion, avoiding signal damage (like pulse distortion, etc.) due to such
conversion and reducing network running cost.
Optical interfaces fall into three types according to different applications: intra-office
communication optical interface, short-distance inter-office communication optical interface,
and long-distance inter-office communication optical interface. They are indicated by
different codes in different applications, as shown in Table 5.
Table 5: Optical interface code
Application
situation
Intra-office Short distance inter-
office
Long distance inter-office
Working
wavelength (nm)
6360 6360 6550 6360 6550
Optical fiber
type
G.652 G.652 G.652 G.652 G.652 G.653
Transmission
distance (km)
≤2 ~65 ~40 ~60
STM-6 I –6 S–6.6 S–6.2 L–6.6 L–6.2 L–6.3
STM-4 I–4 S–4.6 S–4.2 L–4.6 L–4.2 L–4.3
STM-66 I–66 S–66.6 S–66.2 L–66.6 L–66.2 L–66.3
The first letter in the code stands for application situation, i.e. I stand for intra-office
communication, S for short distance inter-office communication, and L for long distance
inter-office communication. The first number following the dash behind the letter stands for
STM rate level, e.g. 6 stands for STM-6 and 66 for STM-66.The second number (the first
number behind the decimal point) stands for the working wavelength region and the type of

34
fiber being used, i.e. 6 and blank stands for 6360nm working with G.652 fiber, 2 for 6550nm
working with G.652 or G.654 fiber, and 3 for 6550nm working with G.653 fiber.
5.4 A Typical Optical fiber communication system:
A basic optical fiber communicates system consists of an optical transmitter (modulator,
channel coupler and optical source e.g. LED, LASER), a transmission channel (optical fiber)
and an optical receiver (Optical amplifier, electronic processing circuitry and optical detector
e.g. PIN, APD)
Source Modulator Repeater
ReceiverWDM
Pumping
LASER
Splice
Connector
Fiber link
Fiber amplifier
Signal in
Signal out
Figure 5.1: A Typical optical fiber communication system
In this figure 5.1 an optical source such as a semiconductor LASER or LED is modulated by
a signal. The output light is introduced into the fiber link through a set of connector or
through a permanent fiber splice. If the link is long, the intensity diminishes because of
attenuation in the fiber and the optical signal may need to be regenerated by an optical
repeater. The optical amplifiers it by means of electronic processing circuits and finally
converts the electrical signal into an optical signal by an optical source. An alternative to
repeating the signal is to optically amplify the light by means of optical amplifier. The WDM
combines the signal beam and a pump laser beam (at two different wavelengths) in an optical
fiber amplifier.

35
Table 6: Representative Parameters for Standard Fibers
Type Core diameter
µm
Cladding
Diameter
µm
Relative
refractive index
difference
(∆)
Application
8/125
Single-mode
8 125 0.1 to 0.2 Long distance
,high
Data rate
50/125
Multimode
50 125 1% to 2% Short distance,
moderate
Data rate
62.5/125
Multimode
62.5 125 1% to 2% Local area
networks
100/140
Multimode
100 140 1% to 2% Local area
networks, short
Distance
5.5 Advantages of optical fiber communication:
The optical fiber communication system has the following advantages by virtue of its
characteristics
a) High bandwidth (10 MHz-km to over 1THz-km)
b) High bit rate (0.1 Gbps to 10Gbps)
c) Low attenuation (0.2dB/km to10 -3 dB/km)
d) Electrical immunity (No RFI, EM interface)
e) Signal security is high (can not be easily tapped, no crosstalk)
f) Ruggedness and flexibility (can be bent of radii of few cms)
g) Falling cost per bandwidth (less than 100/km than coaxial cable)
h) Less time delay than geostationary satellites
i) Long repeater spacing (more than 100km)
j) No hazards of short circuits as in metal wire
k) Light weight and small size (fifty miles per gallon)
l) Signal contains very little power
m) High system reliability and ease of maintenance
n) Lower bit error rates
o) Immunity to adverse temperature and moisture condition

36
5.6 Disadvantages of optical fiber communications:
The transmissions of optical signal suffer from many disadvantages over existing metallic
links. Some of these are:
a) Need for more expensive optical transmitter and receiver
b) Radiation darkening: Optical glass darkens when exposed nuclear radiation
c) Some doubt in relation to the long-term reliability of optical fibers in the presence of
moisture (effects of stress correction)
d) Cannot carry electrical power to operate terminal devices
e) An independent electrical power feed is required for any electronic repeater
f) More difficult and expensive to splice than wire
g) Self phase modulation
h) Cross phase modulation
i) Four wave mixing
5.7 Application of optical fiber communication:
a) Telecommunications: Optical fibers are now the standard point to point or point to
multipoint cable communication link.
b) Local Area Network (LAN’s): Multimode fiber is commonly used the “backbone” to
carry switch, hubs, bridge, router of LAN’s from where copper coaxial cable or twisted pair
takes the data to the desktops.
c) Submarine cable: International communication link is used Optical submarine cable
d) Cable TV: As mention above domestic cable TV networks use optical because of its very
low power consumption.
e) CCTV: Closed circuit television security systems use optical fiber because of its inherent
security as well as the other advantages above
f) Optical fiber sensors: Many advances have been made in recent years in the use of optical
fiber as sensors. Gas concentration, chemical concentration, pressure, temperature and rate of
rotation can all be sensed using optical fiber. Much work in this field is being done at the
University of Strathcyde
g) Military: In military applications, specially coated optical fibers are connected t missiles
for guidance and target tracking.
h) Auto mobile: In some automobiles, optical fibers directly couple light from headlights and
taillights to the dashboard so the driver can tell they are working.
i) Medicine: In medicine optical fibers in special sterile cables are used to provide light and
to transmit images for the physician for arthroscopic surgery to view inside the body

37
Chapter 6
Establishment of SDH Optical Transmission Networks

38
6.1 Purpose of the Project:
Purpose of the project is to establish connectivity between Core site Ramna and New core
site (Sher-e Bangla Nagar) SBN. Teletalk’s center MSC is in Ramna core site. Ramna MSC
site houses many core equipments such as GMSC, VMSC, HLR’s, IN nodes, GGSN, SGSN,
TRAU, BSC’s etc. On the other hand SBN core site is newly built site which houses HLR-d
and new IN/VAS nodes. Hence STM-16 (2.5 Gbps) link optical link has to be established
between these core sites to connect various core nodes in either TDM (E1/STM-1) or
Ethernet (100 Mbps/1000 Mbps) connectivity.
Figure 6.1: Requirements for Newly STM-16 SDH link
6.2 Site selection including description of site:
Co ordinates of the Ramna and SBN core sites are below:
Ramna latitude 23˚43΄27.25˝N and longitude 90˚24΄35.91˝E
SBN latitude 23˚45΄29.09˝N and longitude 90˚22΄55.32˝E
Road distance is 6 Km and air distance is 4.69 Km from Ramna to SBN.
6.3 Selection of media:
For STM-16 link the only physical media is suitable is Single mode optical fiber cable. Hence
Single Mode G.652 fiber is selected between those sites and has been installed.

39
6.3.1 Optical fiber spec to be added:
a) OPTICAL FIBER CHARACTERISTICS
i. The Fiber shall comply with the design data given in ITU- Recommendation
G.652D.
Table 7: Specification of OFC
Item Construction
Type Single Mode
Material
Core Germanium doped Silica
Cladding Silica
Coating
Dual Layers of UV-cured Acrylate, Color
coded
Mode Field Diameter
9.2 ± 0.4 µm for 1310 nm
10.4 ± 0.8 µm for 1550 nm
Cladding Diameter 125 ± 1 µm
Coating Diameter 242 ± 10 µm
Coating – Cladding Concentricity < 12.0 µm
Concentricity Error ≤ 1.0µm
Non circularity of Cladding ≤ 2 %
Curl radius ≥ 4 m
Cable Cut-off Wavelength ≤ 1260 nm
Zero Dispersion Wavelength 1300 – 1322 nm
Zero Dispersion Slope ≤ 0.095 ps/(nm2
x km)
Dispersion Coefficient
≤ 3.5 ps/(nm x km) at 1310 nm band
≤ 18 ps/(nm x km) at 1550 nm band
Attenuation
< 0.36 dB/Km at 1310nm
< 0.22 dB/Km at 1550 nm

40
ii. Optical Fiber Cable Structure
Table 8: Optical Fiber cables to be proposed by the bidder for this bid are of 48
core meeting following specifications.
Item Construction
Type
Jelly field, loose tube, Single Armored, Duct
type/direct buried, double Sheath with FRP
strength member
Strength Member Fibre Reinforced Plastic (FRP)
Buffer Tubes
Color Coded Loose Buffer Tubes stranded
around the strength member. The tubes to be
filled with Thixotropic Jelly and necessary
plastic fillers to have circular cable core
Core Wrapping Non Hygroscopic Tape
Core Filling Material Petroleum Jelly
Inner Sheath Material
Material Black Polyethylene
Thickne
ss
1.00 ± 0.10 mm
Armoring
Material
Corrugated steel tape or tube, copolymer coated
on both sides
Thickne
ss
Minimum 0.10 mm
Applica
tio
n
Overlapping
Outer Sheath
Material Black Polyethylene
Thickne
ss
2.00 ± 0.20 mm
Cable Diameter
≤17 mm for 24 core
Maximum Permissible Tensile Force > 2000 Newton
Minimum Permissible Bending
Radius
Dynamic : 25 x Diameter
Static (Unloaded): 12.5 x Diameter
Permissible Compressive Stress 3000 Newton / 100 mm
Number of fiber per Buffer Tube 04/06
Number of Buffer Tubes As per requirement
Cable Length in Drum
Minimum 2 Km, with a lower level variation 5%
for all types of OFC.
Cable Marking
Length Marking: at intervals of every odd meter
Number of Fibers in the Cable, running length,
Year of manufacture & Name of Manufacturer

41
iv. FIBER IDENTIFICATION
Each fiber shall be identified by providing suitable individual colors having good color
properties. Colorless fibers shall not be accepted.
v. OPTICAL DISTRIBUTION/TERMINATION FRAME (ODF)
1. The optical distribution/termination frame shall be rack (19 inch. Standard rack)
mounted type and will be installed in suitable position in the equipment room.
2. Optical I Links in the optical distribution/termination frame shall be high grade
FC/PC type. There shall be easy access for splicing and provision for maintenance
facility.
vi. HDPE pipe specification
Table 9: 40mm permanently lubricated HDPE pipe shall be of following minimum
standard and shall have to satisfy following technical specifications.
No Item Unit Value
Test
Standard
1 Material Density 930 to 958 kg/ m2
at 270
C ASTM D1238
2 Heat Reversion Dimension shall not change by more than 3%
ISO2505/
ASTM D1238
3 Crash Resistance Deflection with load not greater than 10% ASTM D2412
4 Tensile strength Newton/mm2
Min. 20
ASTM F2160/
BS 2782
5 Elongation at break % Min. 350
ASTM F2160/
BS 2782
6
Environmental Stress
Cracking Resistance
(ESCR)
Duct shall not crack or split ASTM D1693
7 Impact Strength No crack or split D2444
8
Hydro Static Pressure
Test
No swelling, leakage or bursting ISO1167
9 Coefficient of friction <0.1
10 Type of HDPE duct Spiral Ribbed
11 Lubricated Layer
Must have solid lubricant, clearly visible and white in color,
uniform layer
12
Lubricated Layer
thickness
Should be minimum 10% of wall thickness
13 Duct size (nominal) 40 /33 mm
13a. Outer Diameter 40 ± 0.5 mm
13b. Wall thickness 3.5 ± 0.25 mm
13c. Minimum coil length 500 meter

42
6.4 Justification of Transmission Media:
Synchronous digital hierarchy (SDH) and synchronous optical network (SONET) refer to a
group of fiber-optic transmission rates that can transport digital signals with different
capacities. STM-16 SDH Multiplexer is cost-effective and compact STM-16 SDH
multiplexer equipment designed to manage and derive services from the optical core to
access. The product supports end-to-end provisioning and management of services across all
segments of the optical network. The product is well suited for backbone and high-speed
links. As traffic demand grows, the product ensures a smooth upgrade by allowing support
for DWDM interfaces.
6.5 Site Survey:
Ramna switch room and SBN switch room has available space for installation optical mux.
Required power supply of -48V PDF (power distribution frame) has blank circuit breaker of
30A which can be used for optical Mux.SBN 4th
Floor has been selected for STM-16 SDH
link.
6.6 Collecting information for preparation of List of Materials:
6.6.1 Optical mux
6.6.2 Optical fiber (SM)
6.6.3 Digital Distribution frame (DDF)
6.6.4 Equipment for implementation
6.6.5 DC power cable and grounding cable
6.6.1 Optical mux:
Key features and benefits for Optical Mux include:
• Dual SDH and Data architecture for future-proof flexibility
• 60Gbit/s non-blocking VC-12 switch
• 20Gbit/s non-blocking packet switch
• STM-16, STM-64 and 10GigE aggregate interfaces.
• STM-16 in-service upgradeable to STM-64.
• Embedded DWDM and OTN carrier grade optical transport
• Pre-amplification and booster options for extended reach applications
• Carrier class TDM and packet functionality.
• Ethernet switching and service support for Full service Broadband, IPTV and Business
Ethernet (E-Line, E-LAN)
• High density Ethernet interfaces, with Ethernet Port Extension for managed remote delivery

43
Figure 6.2: Optics OSN-2500
6.6.1.1 Optical interface for Short haul and Long haul:
Table 10: Optical interfaces support distance transmits power and receive power.
Laser
Type
Description Rx.
Sensitivity
Rx.
Overload
Max.Tx
Power
Min.Tx
Power
S1.1 S–Short haul, 1–STM1, 1–1310nm (15 Km) -28dBm -8dBm -8dBm -15dBm
L1.1
L–Long haul, 1–STM1, 1–1310nm (40 Km
-34dBm -10dBm 0 dBm -5dBm
L1.2 L–Long haul, 1–STM1, 2–1550nm (80 Km) -34dBm -10dBm 0 dBm -15dBm
S4.1 S–Short haul, 4–STM4, 1–1310nm (15 Km) -28dBm -8dBm -8dBm -3dBm
L4.1 L–Long haul, 4–STM4, 1–1310nm (40 Km) -28dBm -8dBm +2dBm -3dBm
L4.2 L–Long haul, 4–STM4, 2–1550nm (80 Km -28dBm -8dBm +2dBm 0dBm
V4.1 V–Very long haul, 4–STM4, 2–1550nm (120 Km) -34dBm -18dBm +4dBm -5dBm
S16.1 S–Short haul, 16–STM16, 1–1310nm (15 Km) -18dBm 0 dBm 0 dBm -5dBm
S16.2 S–Short haul, 16–STM16, 2–1550nm (15 Km) -18dBm 0 dBm 0 dBm -5dBm
L16.1 L–Long haul, 16–STM16, 1–1310nm (40 Km) -27dBm -9 dBm +3dBm -2dBm
L16.2 L–Long haul, 16–STM16, 2–1550nm (80 Km -28dBm -9 dBm +3dBm -2dBm
Selection interface card S16.1 Short haul 1310 nm (15Km).
6.6.1.2 Electrical interface with relation materials:
Its function is to multiplex the lower-rate signals in the tributary port to the higher- rate signal
STM-N in the line port, or to extract the lower-rate tributary signals from STM-N signal.
Please note that its line port inputs/outputs one STM-N signal, while the tributary port can
output/input multiple paths of lower-rate tributary signals. When the low rate tributary signals
are multiplexed into STM-N frame (to multiplex low rate signal into line), there is a cross
function.
PQM: Supports 63 both E1 and T1 signals provides 120 Ω balanced E1 interface and 100 Ω
balanced T1 interface.
PQ1: Provides 75 Ω unbalanced interface 120 Ω balanced Supports 63 E1 signals and
interface.

44
DDF: Digital distribution frame 19 inch and unbalance coaxial cable
Table 11: Tributary interface for electrical card
6.6.2 Optical fiber (SM):
6.6.2.1 Selection of Optical distribution frame (ODF):
ODF is used for telecommunications closet cross-connect area. To complete cabling bundle
solution for installer to manage, protect, and connect equipments and structured cabling
items. To align with rack units for organizing and support fiber cables. Bundling with rack
mount enclosure & easy plug and play fiber cassette module.
Figure 6.3: Optical distribution frame (ODF) for optical fiber

45
6.6.2.2 Optical connector:
An optical fiber connector terminates the end of an optical fiber, and enables quicker
connection and disconnection than splicing. The connectors mechanically couple and align
the cores of fibers so that light can pass. Most optical fiber connectors are spring-loaded: The
fiber end faces of the two connectors are pressed together, resulting in a direct glass to glass
or plastic to plastic contact, avoiding any glass to air or plastic to air interfaces, which would
result in higher connector losses. Connectors with a plastic shell (such as SC, FC, SC etc
connectors) typically use a color-coded shell. Standard color codlings for jackets and boots
(or connector shells) are shown below.
Figure 6.4: Optical Connector
6.6.2.3 Optical patch cord:
A patch cord length of optical fiber that has a plug at each end is used to make connections
at a patch board.
Figure 6.5: Optical patch cord

46
6.6.2.4 Cable Plant Link Loss Budget Analysis:
Loss budget analysis is the calculation and verification of a fiber optic system's operating
characteristics. This encompasses items such as routing, electronics, wavelengths, fiber type,
and circuit length. Attenuation and bandwidth are the key parameters for budget loss analysis.
6.6.2.5 Analyze Link Loss in the Design Stage:
Prior to designing or installing a fiber optic system, a loss budget analysis is recommended to
make certain the system will work over the proposed link. Both the passive and active
components of the circuit have to be included in the budget loss calculation. Passive loss is
made up of fiber loss, connector loss, and splice loss. Don't forget any couplers or splitters in
the link. Active components are system gain, wavelength, transmitter power, receiver
sensitivity, and dynamic range. Prior to system turn up, test the circuit with a source and FO
power meter to ensure that it is within the loss budget.
The idea of a loss budget is to insure the network equipment will work over the installed fiber
optic link. It is normal to be conservative over the specifications! Don't use the best possible
specs for fiber attenuation or connector loss.
The best way to illustrate calculating a loss budget is to show how it's done for a 2 km
multimode link with 5 connections (2 connectors at each end and 3 connections at patch
panels in the link) and one splice in the middle. See the drawings below of the link layout and
the instantaneous power in the link at any point along its length, scaled exactly to the link
drawing above it.
Figure 6.6: Optical link losses

47
6.6.2.6 Cable Plant Passive Component Loss:
Step 1 Fiber loss at the operating wavelength
Table 12: Operation fiber losses
Step 2. Connector Loss:
Multimode connectors will have losses of 0.2-0.5 dB typically. Single mode connectors,
which are factory made and fusion spliced on will have losses of 0.1-0.2 dB. Field terminated
single mode connectors may have losses as high as 0.5-1.0 dB. Let's calculate it at both
typical and worst case values.
Remember that we include all the components in the complete link, including the connectors
on each end.
Table 13: All connectors are allowed 0.75 max per EIA/TIA 568 standard
Connector Loss 0.5 dB (typical
adhesive/polish conn)
0.75dB(TIA -568 max
acceptable)
Total No of connector 4 5
Total connector Loss 2.0 dB 3.75 dB
Cable Length 2.0Km 2.0Km 6.0 Km
Fiber Type Multimode Single mode
Wave length (nm) 850 1300 1310 1550
Fiber
Atten.dB/Km
3[3.5] 1[1.5] 0.4[1/0.5] 0.3[1/0.5]
Total Fiber Loss 6.0[7.0] 2.0[3.0] 2.4

48
Step 3. Splice Loss
Multimode splices are usually made with mechanical splices, although some fusion splicing
is used. The larger core and multiple layers make fusion splicing about the same loss as
mechanical splicing, but fusion is more reliable in adverse environments. 0.1-0.5 dB for
multimode splices, 0.3 being a good average for an experienced installer. Fusion splicing of
single mode fiber will typically have less than 0.05 dB (that's right, less than a tenth of a dB)
Table 14: All splices are allowed 0.3 max per EIA/TIA 568 standard)
Typical Splice Loss 0.3 dB
Total No of splice 4
Total Splice Loss 1.2 dB
Step4. Total Passive System Attenuation
Table 15: Add the fiber loss, connector and splice losses to get the link loss
Remember these should be the criteria for testing. Allow +/- 0.2 -0.5 dB for measurement
uncertainty and that becomes your pass/fail criterion.
Typical TIA 568 Max
850 nm 1310nm 850nm 1300nm
Total Fiber Loss (dB) 6.0 2.4 7.0 3.0
Total Connector Loss (dB) 1.5 2.0 3.75 3.75
Total Splice Loss (dB) 0.3 1.2 0.3 0.3
Other (dB) 0 0 0 0
Total Link Loss (dB) 7.8 5.6 11.05 7.05

49
6.6.2.7 Equipment Link Loss Budget Calculation:
Link loss budget for network hardware depends on the dynamic range, the difference
between the sensitivity of the receiver and the output of the source into the fiber. We need
some margin for system degradation over time or environment, so subtract that margin (as
much as 3dB) to get the loss budget for the link.
Step 5. Data from Manufacturer's Specification for Active Components (Typical 100
Mb/s link)
Table 16: Manufacture Spec
Operating Wavelength (nm) 1300
Fiber type M
Receive Sens. (dB@ required BER) -31
Average Transmitter Output (dBm) -16
Dynamic Range (dB) 15
Recommended Excess Margin (dB) 3
Step 6. Loss Margin Calculation:
Table 17: Loss Margin Calculation
Dynamic Range (dB) (above) 1.5 1.5
Cable Plant Link Loss (dB) 3.8(Type) 7.05 (TIA)
Link Loss Margin (dB) 11.2 7.95
As a general rule, the Link Loss Margin should be greater than approximately 3 dB to allow
for link degradation over time. LEDs in the transmitter may age and lose power, connectors
or splices may degrade or connectors may get dirty if opened for rerouting or testing. If
cables are accidentally cut, excess margin will be needed to accommodate splices for
restoration.
6.6.3 Digital Distribution Frame (DDF):
A Digital Distribution Frame (DDF) is the interface when coaxial cable has to be terminated,
organized or cross-connected in long-distant transport networks, or in access Networks close
to subscribers. In fixed networks, a DDF is installed between the exchange and transmission
equipment, to mention one example. In mobile networks, DDFs can also serve as the
interface between an MSC (Mobile Services Switching Centre)
or BSC (Base Station Controller) and the transmission equipment.

50
Figure 6.7: DDF with Tributary Cable
Digital distribution frame (DDF) consists of a slim line rack/frame with hangover type
modules blocks. DDF comes in two types of versions 120 OHM & 75 OHM. 75 ohm
Digital Distribution Frames are used to terminate, cross-connect and inter-connect 75 ohm
coaxial cables and to supervise digital transmission equipment.
6.6.4 Equipment for implementation:
6.6.4.1 Splice Machine:
Splicing is the act of joining two optical fibers end-to-end using heat. The goal is to fuse the
two fibers together in such a way that light passing through the fibers is not scattered or
reflected back by the splice, and so that the splice and the region surrounding it are almost as
strong as the virgin fiber itself. The source of heat is usually an electric arc, but can also be a
laser, or a gas flame, or a tungsten filament through which current is passed.
Figure 6.8: Splice Machine

51
6.6.4.2 Optical power and Laser source:
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. Other
general purpose light power measuring devices are usually called radiometers, photometers,
laser power meters, light meters or lux meters
Figure 6.9: Optical power meter and Laser source
6.6.4.3 Optical time domain reflecto meter (OTDR):
An optical time-domain reflectometer (OTDR) is an optoelectronic instrument used to
characterize an optical fiber. An OTDR injects a series of optical pulses into the fiber under
test. It also extracts, from the same end of the fiber, light that is scattered (Rayleigh
backscatter) or reflected back from points along the fiber. The strength of the return pulses is
measured and integrated as a function of time, and is plotted as a function of fiber length.An
OTDR may be used for estimating the fiber's length and overall attenuation, including splice
and mated-connector losses. It may also be used to locate faults, such as breaks, and to
measure optical return loss. To measure the attenuation of multiple fibers, it is advisable to
test from each end and then average the results, however this considerable extra work is
contrary to the common claim that testing can be performed from only one end of the fiber.
Figure 6.10: Time Domain Reflecto meter (OTDR)
6.6.4.4 Bit error rate tester (E1 Analyzer):
A bit error rate tester (BERT), also known as a bit error ratio tester or bit error rate test
solution (BERTs) is electronic test equipment used to test the quality of signal transmission
of single components or complete systems

52
Figure 6.11: E1 Analyzer
6.6.5 DC power cable and grounding cable:
Optics mux can accept DC power .The OSN-2500 can accept power from a –48 VDC (–42 to
–56 VDC) source that connects to one (primary) or two (secondary/redundant) –48 VDC
power distribution frame (PDF). Each DC PDF must be connected to a dedicated 35A
regulated source. PGND is to connected with body of the Mux Cabinet and Rack
6.7 Implementation Plan:
At the edge of optical Radio Access Network, the need is for an optical platform that can be
cost effectively hub 2 Mbps from BS (Base station), whereas at the controller site large
platform is typically required to enable multiple MSC and BSCs to be collocated .This
functionality required in these application is the multiple subtended rings, and groom/
consolidate in the traffic in a blocking VC-12 Switch. The introduction of IP base sections
will be mean that operators who can migrate existing 2 Mbps backhaul circuits to Ethernet
technology can quickly take advantage more efficient packet transport .Optical Mux (2.5 G)
family fulfils all these requirement ,at the same time is able to optimize Ethernet transport
through packet aggregation and statistical gain.
Significant service revenue is still generated from TDM services, which now have to be
supported alongside today’s rapidly growing packet based services. During this change,
equipment deployed in access and Metro networks must have architecture with the flexibility
and cost effectiveness to satisfy all demands of new data and TDM services. This means that
the required products need to change and scale without expensive upgrades and stranded
costs. To that end, all of the OSN-2500 family feature universal traffic slots, supporting a
wide and growing range of multi-rate, high-density TDM & Data cards.
6.8 Working schedule:
Within 45 days working should be completed according to rules of procurement policy
Teletalk (PPT).
Date of working start on 03-05-2011.
Date of ending on 04-07-2011

53
6.9 Installations:
6.9.1 Installing Cabinet:
The Universal adopts standard 19-inch N68-22 cabinet, with flexible and simple structure,
and powerful versatility. The dimensions are 2200 mm (height with door lintel) x 600 mm
(width) x 800 mm (depth). Five cabinets can satisfy the requirements for full configuration of
the OSN-2500.According to different equipment rooms, a cabinet can be installed on the
cement floor or ESD preventive floor. When two or more cabinets are installed in the same
row, they must be combined and fixed.
Figure 6.12: Cabinet installation
6.9.2 Planning Support Positions:
6.9.2.1 Determining Cabinet Positions:
Before installing cabinets, plan available space of the equipment room. Keep sufficient space
around cabinets for maintenance and operation purposes
6.9.2.2 Marking Installation Hole Positions:
To mark installation hole positions, do as follows:
Specify installation positions for the supports with reference to the benchmark dimensions
and the support dimensions specified in the construction plan. Mark a few points for line
drawing with a long tape and draw two straight lines parallel to the benchmark with a
distance of 690 mm between them. According to the design requirements, specify the
installation holes for the first support on the two lines. With these holes as reference, mark
the installation holes for other supports one by one. To avoid faults, measure all location lines
again after marking the holes to ensure correct dimensions. The holes for installing supports
for a single cabinet

54
Figure 6.13: Hole installing supports positions for a single cabinet
make holes 52 mm to 60 mm deep. Make sure that the depths of all holes are the same.
Clean the dust inside the holes with a vacuum cleaner. Measure the depth to make sure that
the depths of all holes are the same. If the ground is too hard or smooth to settle the drill bit,
punch a sample pit first for easy drilling. Drawing lines and drilling holes are the fundamental
work for hardware installation. Good quality is the prerequisite to guarantee the quality of the
overall installation. If the accuracy is not high enough, the future work will be greatly
affected.
6.9.3 Installing Supports and Slide Rails:
6.9.3.1 Installing Expansion Bolts:
Before fixing expansion bolts, clean up the dust inside and around the holes with a vacuum
cleaner. Measure The distance between the holes and place the supports to check whether the
supports and holes match exactly. For the holes with big deviation, plan and drill new holes
before installing expansion bolts in them.
To install an expansion bolt, do as follows:
Take expansion tube and nut off the expansion bolt, and put them vertically into a hole after
the guiding rib on the expansion nut has been inserted in to the guiding slot. Strike directly on
the expansion tube with a rubber hammer until it is completely driven into the ground. The
installation of an expansion tube and an expansion nut.

55
( 1)
( 2)
( 3)
( 4)
(1) Expansion
tube
(2) Guiding slot
on expansion tube
(3) Expansion nut
(4) Guiding rib on
expansion nut
Figure 6.14: Installation of an expansion tube and an expansion nut
6.9.3.2 Adjusting Support Height:
To ensure that the upper surface of slide rails and the upper surface of the ESD-preventive
floor are on the same level after the supports and slide rails are assembled, it is required to
adjust all the supports to the preset height before installation.
To adjust the support height, do as follows:
Measure the height of the upper surface of the ESD-preventive floor. Make the value minus
the height of the slide rail (50 mm) to get the preset height of the supports. According to the
ESD-preventive floor height mark on the supports, adjust all the supports to the preset height
and tighten the height-locking bolts to 45 Nm with a torque spanner. Tighten the bolts in the
middle and then those at both sides
(1) Height-locking bolts (in the
middle)
(2) Height-locking bolt (at both sides)
two slide rails are equal in length.
6.9.3.3 Fasten all bolts.Assembling Supports and Slide Rails:
To assemble the supports and slide rails, do as follows:
Assemble the supports and slide rails together with M12 x 30 bolts, spring washer and flat
washer. Correct the support positions before fastening all bolts to make the diagonal lines of
the
(1) Support (2) Slide rail ( 3) Bolt M12 × 30 (4) Spring 12
(5) Flat washer 12 (2) Diagonal line A (7) Diagonal line B
6.9.3.4 Fixing Supports:
To fix the supports, do as follows:
(1)
A
(2)
B
(3)
(4)
(5)

56
Align the support installation holes with the corresponding expansion bolt holes. Fit the
spring and flat washers on M12 x 60 bolt, and insert the bolts vertically into the expansion
bolt holes through the support installation holes. Correct the support positions and screw M12
x 60 bolts to 45 Nm
(1) Bolt M12 ×60 (2) Spring washer 12 (3) Flat washer 12 (4) Expansion tube
(5) Expansion nut
Figure 6.15: Assembly of support and slide rails
When installing supports for a row of cabinets, align all supports by front side and keep the
spacing adjacent supports as 128 mm for convenience of connecting cabinets
128
Figure 6.16: Relative positions of supports
(1)
(2)
(3)
(4)
(5)

57
6.9.3.5 Installing Floor Holder Fixing Components:
Floor holder fixing components are used to fix front floor holder and back floor holder.
Before the cabinets are positioned, the floor holder fixing components must be fixed under
the slide rails.
3.9.4 Leveling Cabinets:
6.9.4.1 Positioning Cabinets:
To position a cabinet, do as follows:
Determine the front view of a cabinet. Lift it onto the slide rails. Align the four fixing holes in
the cabinet with the four holes in the slide rails.
6.9.4.2 Installing Insulation Plates:
Put the insulation plates on the slide rails under the cabinet. Each cabinet requires two
insulation plates.
(2)
(1)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
Figure 6.17: Complete installation mux cabinet
(1) Cabinet (2) Slide rail (3) Support
(4) Nut 12 (5) Flat washer 12 (6) Washer
(7) Insulation plate (8) Spring washer 12 (9) Bolt M12x45

58
6.9.4.3 Leveling Cabinets:
To level the cabinets, do as follows:
Place horizontal rulers in both longitudinal and latitudinal directions on the top surface of the
cabinet to check the levelness.
6.9.5 Fixing Cabinets:
6.9.5.1 Fixing Bottom of Cabinet:
To fix the cabinet bottom, do as follows:
Fit the vertically into the connection holes in the slide rails through the lower enclosure
spring washers on M12x45 bolts (the big flat washers and insulation coverings have been
installed in the cabinet).insert the bolts frame of the cabinet. Fit the flat washers and nuts and
screw M12x45 bolts to 45 Nm. Be sure to fasten the bolts in cross way to reduce the stress
between bolts and cabinet.
6.9.5.2 Fixing Top of Combined Cabinets:
When two or more cabinets are installed, they must be combined and fixed by connecting
plates. The connecting plates for combining cabinets are installed on the top of the cabinets
and they are delivered with cabinets
6.10 Labeling of Optical Fibers:
6.10.1 Introduction to the Labels:
These labels are affixed to the optical fibers that connect the optical interfaces on the boards
in a frame, or on the device boxes. There are two types of labels for optical fibers: one is for
the fiber that connects the optical interfaces on two devices, the other is for the fiber that
connects the device and the Optical Distribution Frame (ODF). Labels for Fiber that
Connects Two Devices
Label Information Meanings
The information on both sides of the labels affixed to the optical fiber that connects two
devices. Information on labels affixed to the fiber between two devices

59
Content Meaning Example
MN-B-C-D-
R/T
MN: cabinet
number
For example, A01
B: frame number Numbered in top-down order with two digits, for example, 01
C: physical slot
number
Numbered in top-down and left-right order with two digits, for
example, 01
D: optical
interface number
Numbered in top-down and left-right order with two digits, for
example, 05
R: optical
receiving
interface
T: optical
transmitting
interface
–
MN-B-C-D-
R/T
MN: cabinet
number
The meanings are the same as above. When the local device
and the opposite end device are not in the same equipment
room, MN can be the name of the equipment room.
B: frame number
C: physical slot
number
D: optical
interface number
R: optical
receiving
interface
T: optical
transmitting
interface
–

60
Label Example
Shows the label on the optical fiber between two devices:
Example of the label on the optical fiber between two devices
A01-01-05-05-R indicates that the local end of the optical fiber is connected with Optical
Receiving Interface 05 on Slot 5, Frame 01 in the cabinet at Row A, Column 01 in the
equipment room.
G01-01-01-01-T indicates that the opposite end of the optical fiber is connected with Optical
Transmitting Interface 01 on Slot 01, Frame 01 in the cabinet at Row G, Column 01 in the
equipment room
6.10.2 Labels for Fiber that Connects the Device and the ODF:
Label Information Meanings
The information on both sides of the labels affixed to the optical fiber that connects the
device and the ODF.

61
Information on labels affixed to the fiber between the device and the ODF
MN-B-C-D-R/T
MN: cabinet number For example, A01
B: frame number
Numbered in bottom-up order with two
digits, for example, 01
C: physical slot
number
Numbered in top-down and left-right
order with two digits, for example, 01.
D: optical interface
number
order with two digits, for example, 05
R: optical receiving
interface
T: optical transmitting
interface
–
ODF-MN-B-C-R/T
MN: row number and
column number of
ODF
Numbered in the same rule as that of the
cabinets, for example, G01 indicates an
ODF at Row G, Column 01
B: row number of the
terminal device
Range from 01 to 99, for example, 01-01
C: column number of
the terminal device
interface
T: optical transmitting
interface
–

62
Label Example
shows the label on the optical fiber between the device and the ODF.
Example of the label on the optical fiber between the device and the ODF
ODF-G01-01-01-R indicates that the local end of the optical fiber is connected with the
optical receiving terminal at Row 01, Column 01 of the ODF at Row G, Column 01 in the
equipment room.
A01-01-05-05-R indicates that the opposite end of the optical fiber is connected with Optical
Receiving Interface 5 on Slot 05, frame 01 in the cabinet at Row A, Column 01 in the
equipment room.
6.11 Labeling of Trunk Cables:
6.11.1 Introduction to the Labels:
There are two types of labels for trunk cables. One type is used for the trunk cable connecting
two devices, such as the trunk board and built-in transmission unit, or two trunk boards. The
other type is used for connecting the device and the Digital Distribution Frame (DDF).
The trunk cables include 75Ω/120Ω E1 cables, 120Ω T1 cables, 34M, 45M, 140M, 155M
cables and 120-to-75Ω trunk cables, as well as clock cables.

63
6.11.2 Labels for Trunk Cable That Connects Two Devices:
Label Information Meanings:
shows the information on both sides of the labels affixed to the trunk cable that connects two
devices.
Information on labels affixed to the trunk cable between two devices
MN-B-C-D-
R/T
MN: cabinet
number
For example, A01
B: frame number
Numbered in bottom-up order with
two digits, for example, 01
C: physical slot
number
D: cable number
R: optical
receiving interface
T: optical
transmitting
interface
MN-B-C-D-
R/T
Same as above Same as above

64
Label Example
shows the label on the trunk cable between two devices:
Example of the label on the trunk cable between two devices
G01-01-05-12-T indicates that the local end of the trunk cable is connected with the
transmitting terminal of Trunk Cable 12 on Slot 05, Frame 01 in the cabinet at Row G,
Column 01 in the equipment room.
D02-01-01-10-R indicates that the opposite end of the trunk cable is connected with the
receiving terminal of Trunk Cable 10 on Slot 01, Frame 01 in cabinet at Row D, Column 02
in the equipment room
6.11.3 Labels for Trunk Cable That Connects the Device and the DDF:
Label Information Meanings:
shows the information on both sides of the labels affixed to the trunk cable that connects the
device and the DDF.
Information on labels affixed to the trunk cable between the device and the DDF
MN-B-C-D-
R/T
MN: cabinet
number
For example, A01
B: frame number Numbered in bottom-up order with
two digits, for example, 01
C: physical slot
number
order with two digits, for example,
01
D: cable number Numbered in top-down and left-right
order with two digits, for example,
05

65
interface
T: optical
transmitting
interface
–
DDF-MN-B-
C-D/R/T
MN: row number
and column number
of the DDF
Numbered in the same rule as that of
the cabinets, for example, G01
indicates a DDF at Row G, Column
01.
B: row number of
the terminal Range from 01 to 99, for example:
01-01.C: column number
of the terminal
D: direction A or B
interface
T: optical
transmitting
interface
There is such a mark in DDF:
A: indicating the DDF terminals are
connected to the optical network
equipment
B: indicating the DDF terminals are
connected to the switching
equipment
Label Example:
shows the label on the trunk cable between the device and the DDF:
Example of the label on the trunk cable between the device and the DDF

66
A01-03-01-01-R indicates that local end of the trunk cable is connected with the receiving
terminal of Trunk Cable 01 in Slot 01, Frame 03 of the cabinet at Row A, Column 01 in the
equipment room.
DDF-G01-01-01-AR indicates that the opposite end of the trunk cable is connected with the
receiving terminal of Direction A (connected to optical network equipment) at Row 01,
Column 01 of the DDF at Row G and Column 01 in the equipment room.
6.12 Labeling of Power Cables:
6.12.1 Labels for DC Power Cables:
Introduction to the Labels:
The labels are affixed to the DC cables that provide power for the cabinets, and the protection
grounding cables, including the –48V, PGND, and BGND cables. The labels for DC power
cables are affixed to one side of the identification plates on cable ties.
6.12.2 Label Information Meanings:
shows the information carried on the labels for the DC power cables:
Information on labels affixed to the DC power cables
Content Meaning
MN(BC)-–48V1 MN (BC): BC is written right under MN.
On the equipment cabinet side, only MN is used to
identify the cabinet.
On the power cabinet side, MN identifies the row and
column number of the power distribution equipment
like the control cabinet and distribution cabinet, BC
identifies the row and column number of the –48V
connecter (if there is no row number or column
number, or the connecter can be identified without
them, BC can be omitted). BGND and PGND have no
row and column number for identification.
MN(BC)-–48V2
MN(BC)-BGND
MN(BC)-PGND

67
The label only carries location information about the opposite equipment, the control cabinet
identification plates with the labels should face up, and the text on the labels in the same
cabinet should be or the distribution cabinet, while information of the local end is not
necessary. 0 lists the information of two –48V power supplies on the label. The information
for other DC voltages (such as 24V, 60V) should be given in similar methods.
Label Example:
Make sure that labels are affixed in correction direction. That is, after the cable ties are
bundled onto the cable, the in the same direction
(1) (2)
TO:
A01 -48V2
B08
TO:
B03 -48V2
Example of the labels on the DC power cable
In 0, (1) indicates the label on the equipment cabinet side, which carries the information
about the position of the cable on the power distribution cabinet. (2) Indicates the label on the
distribution cabinet side, which carries the information about the position of the cable on the
equipment cabinet side.
On the equipment cabinet side, the label marked A01/B08-–48V2 on the cable indicates that
the cable is –48V2 DC supply, which is from the eighth connecter on the second row of –48V
bus bar in the cabinet at Row A, and Column 1 in the equipment room.
On the distribution cabinet side, the label marked B03-–48V2 indicates that the cable is –
48V2 DC supply, which is from the equipment cabinet at Row B, Column 03 in the
equipment room. PGND and BGND are copper bars, on which all the terminals are
connected. In this case, it is only necessary to specify the row and column of the power
distribution cabinet. For example, A01-BGND means that the power cable is a BGND cable
that equipment room connects to the BGND copper bar of the power distribution cabinet at
Row A, Column 01

68
6.13 Insert the optical Interfaces:
STM-16 optical card has been installed on the optical MUX figure 6.31. Optical mux is
installed inside the cabinet. Insert the optical interfaces (STM-16 S16.1 card) on the optics
rack. It is inserted the Processing interface (PQ1 card), the Tributary interface (D75S card),
Optical Cross-connects (OXCs) processing board CXL16 and Digital cross-connects (DXCs)
board GXCSA .
Figure 6.18: Optical card installation
1. Two pairs LC for 2 X 2.5Gbit/s signals dispersion compensator
2. Inserted in Slots 1~8, 11~17
3. Cross-connection
VC-12, VC-3 and VC-4
AU4-4C, AU4-8C, AU4-16C and AU4-64C
4. Network Protection Control
SNCP at VC-3 & VC-12, MSP
5. Tributary Board and Controls TPS

69
6.14 Between Ramna and Sher-e Bangla Nagar (SBN) Connect optical fiber
link:
First core optical fiber is to be connected Ramna optical cross-conects (OXCs) transmit (TX)
and SBN optical cross-conects (OXCs) receive (RX) .Then Second core optical fiber is to be
connected Ramna receive (RX) and SBN optical cross-conects transmit (TX).Finally is getted
Raman receive power -16 dBm and SBN receive power -17 dBm. Optical Mux thresold
receive level is -28 dBm.So STM-16 SDH link has been completed from Ramna to SBN .
Figure 6.19:Completed the STM-16 optical link
6.15 Checking Hardware Installation:
6.15.1 Hardware Installation Check:
Checking Cabinets
Following are the cabinet check items:
The cabinets in a row are correctly positioned, and both the front and back planes of the
cabinets are aligned. All bolts are screwed tightly. All bolts have flat washers and spring
washers, and they are fixed in correct direction. The components and cables of the cabinets
are complete and in good condition. All labels are correct, clear and complete. There are no
surplus cable ties, stubs or other sundries in the cabinets. The front and back doors and side
panels are clean without defilement or handprint. After all cables are laid, the small cover
plates on both the top and bottom of cabinets cover corresponding cabling holes, thus
preventing animals or dust from entry. Checking Cable Distribution
6.15.2 Checking Power Cables and Protection Grounding Cables:
The check items include:
The power cables and protection grounding cables from DC power distribution cabinet to
power distribution frames in the top of cabinets are connected securely. The power cables
and protection grounding cables from power distribution frames to service frames are
connected securely. Grounding polarities are correct and the contacts are good. The power
cables and protection grounding cables are not laid together with signal cables.
6.15.3 Internal Checking Cables:
The check items include:

70
The cable connections are correct and firm. The Cable ties are in correct positions and spaced
properly. The cable ties are not overlapped and there are no sharp ends.
6.15.4 Checking Trunk Cables, Optical Fibers and Network Cables:
The check items include:The cables are not stretched at turnings.The cabling paths are
consistent with the requirements and the cable ties arespaced properly. The cables are straight
and smooth. There is no cable crossover in the cabinet and the cables outside cabinet are
bundled according to the cabinets they are connected to.The cables in the cabling troughs and
on the cabling ladders are orderly arranged and all the cables are bundled with no damage on
the coating. The cables have proper redundancy and the cable ties have no sharp ends or
overlaps.
6.15.5 Checking Connectors and Sockets:
i) Checking Connectors
The latches of cable connectors must be tightly locked and the coaxial cable connectors be
fastened tightly.
ii) Checking Sockets
The sockets include trunk cable sockets, network cable sockets and HEADER sockets for all
backplanes. There must be neither lack of pins nor short-circuit resulting from bent pins.
iii) Other Checks
Labels
All labels must be clean, tidy and in correct positions.
6.15.6 Cabling Trough and Cabling Rack:
There must be no such sundries as cable ties, stubs, or dryer bags left in the cabling troughs
and cabinets, on the cabling rack and top of the cabinets, or under the movable floor around
the cabinets.
6.15.7 Environment of the Equipment Room:
There must be no useless objects in the equipment room and all the necessities must be neatly
arranged in the room. The workbench and movable floor must be clean and tidy.
6.15.8 Checking Power Supplies for Cabinets and Frames:
The check on power supply for the cabinets and frames is to see whether there is short circuit
in all output power lines from the DC power distribution frame, whether the input DC

71
voltage to the optics cabinets is normal, whether the visual and audio alarm function of the
frames in all cabinets is normal, and whether the input DC voltage to all internal components
of the cabinets is normal.
The check steps are described as follows:
Shut down the power supply of DC power distribution cabinet, and set all AC power sockets
and switches to OFF. Set the multimeter to ohm range and check whether there is short
circuit between power supplies (–48V1 and –48V2) of the DC power distribution frame and
between grounds (BGND and PGND), and whether the power supply is disconnected from
the ground. The hot wire, ground wire and neutral wire of every socket must not be shorted.
Set all the switches of the power distribution frame in the top of the cabinet to OFF, and then
power on the DC power distribution cabinet. In the case of no load, use the multimeter to
check whether the output of power supply is within the allowed voltage range (–57 V to –40
V). At this time, the red ALM indicator on the power distribution frame should flash and the
buzzer will give off audible alarm upon setting the ALARM switch to ON. Set all the
switches of the power distribution frame in the top of the cabinet to ON after making sure
that there is no board inserted into the corresponding slot on the backplane. At this time, there
should be no power alarm or audible alarm and the red WARN indicator should not light up.
The fan frame should operate normally and there is no abnormal noise. Check whether other
devices in the cabinets are with power supply input of –48 V and their voltage is within the
proper range (–57 V to –40 V). If everything is normal, the power supply is in good
condition. If any of the above items does not meet the requirement, find out the reason and
perform troubleshooting before the power-on check. The alarm indicators on the power
distribution frame can indicate analog value alarm information and Boolean value alarm
information.
To analyze analog value alarm information, follow the method below:
Check whether there is an alarm for analog values through the background, including voltage
of the two power supplies, humidity sensor, and temperature sensor. Check whether the
reported values are normal.
Table 18: Analog values
Item Default normal value
Voltage –42 V to –58 V
Humidity 5% to 90%
Temperature 5°C to 70°C
If the above values are normal, check whether the values are beyond the upper
limit or lower limit configured in the background.
To analyze Boolean value alarm information, follow the method below:
1) Check whether there is Boolean value related alarm, including:
Lightning protection fault of dual channel
Power distribution output switch fault of four to eight channels
Inverter fault of three channels
Preserved Boolean value fault of three channels

72
2) Check whether the corresponding Boolean value detection is configured. If
yes, check whether there is alarm for Boolean value and check whether the
alarm is normal. If Boolean value detection is not configured, execute alarm
disabling/enabling command through the background to mask those Boolean
values not configured
6.15.9 Performing Board Power-On Test:
The working status of a board powered on can be known according to indicators on the board
front panel. For the meanings of board indicators, refer to Universal Media Hardware
Description Manual.
The steps to conduct the trial power-on check are as follows:
1) Check whether the input and output cables of –48 VDC power supply are
correctly connected and whether the connection cables are firm.
2) Set all the switches on DC power distribution frame for the boards to OFF,
and then insert the boards into the slots on the backplanes and fasten the front
planes of the boards.
3) Set the power switches controlling the frames to ON. At this time, all board
indicators should be normal. If the indicators of all boards do not light up
after the power switches are turned on, it indicates no –48 VDC input or error
of the input terminal connection. If the power switch jumps upon being
closed, it means there would be short-circuit of payload or connection error
on the output terminal (short circuit).

73
6.16 Software commissioning:
6.16.1 Starting the PC
This part describes how to start the PC installed with the Windows operating system.
Procedure
Step 1 Power on the monitor of the PC.
Step 2 Powers on the PC. The Microsoft Windows starts automatically and the login window
is displayed.
Step 3 Enter the user name and password for an administrator in the login window.
NOTE
If the PC is powered on, start with step 3.
Step 4 Click OK to display the desktop of the Window operating system.
….End
6.16.2 Setting IP Address for a PC:
The IP address of the PC and that of the equipment should be in the same network section.
Otherwise, the login to the NE by using the T2000-LCT fails. This part describes how to set
the IP address for the PC. Make sure you can log in to the equipment by using the T2000-
LCT.
Procedure
Step 1 Right-click My Network Places icon on the desktop and select Properties to display
Network Connections window.
Step 2 In the Network Connections window, right-click Local Area Connection and
choose
Properties from the shortcut menu to display the Local Area Connection Properties dialog
Step 3 Click the General tab. Select Internet Protocol (TCP/IP) from the connection uses
the items list.
Step 4 Click Properties to display the Internet Protocol (TCP/IP) Properties dialog box.
Step 5 Select Use the following IP address from the Internet Protocol (TCP/IP)
box. Set the IP address as follows:
IP address: 129.9.0.250
Subnet mask: 255.255.0.0
NOTE:
The IP section for the equipment is 129.9.0.0. The IP address for the PC must be in the same
network section with the equipment. The IP address given in the step is just an example. If
the IP address of the PC is not the same as that of the equipment, the PC prompts the IP
conflict. In this case, re-set the IP address for the PC.
Step 6 Clicks OK.
----End
6.16.3 Starting the T2000-LCT Server:
The T2000-LCT server provides services for the T2000-LCT clients. The T2000-LCT clients
can only be started after the T2000-LCT server starts. This section describes how to start the
T2000-LCT server on the PC.

74
Prerequisite
The following tasks must have been performed:
The T2000-LCT must have been installed in a correct manner.
The IP address of the PC must have been set.
Tools and Meters
Procedure
Step 1 Double-click the T2000LCT-Server icon. The User Login dialog box is displayed in
a few seconds.
Step 2 Fill in the User Name, Password and Server fields in the login dialog box.
User: admin (default)
Password: T2000 (default)
Server: Local
Step 3 Wait a few minutes until the "Ems server", "Security Server", "Topo server" and
"Database
Server Process" are all in the Running state. Then, the T2000-LCT server is being started
successfully.
----End
6.16.4 Network Element Commissioning
OptiX OSN 2500 Intelligent Optical Transmission System
Logging in to an NE
After the T2000-LCT client interface is displayed, log in to the NE for NE commissioning.
This section describes how to use the T2000-LCT client to log in to the NE for
commissioning.
Prerequisite
The following tasks must have been performed:
Precaution
If you use the LCT terminal to log in to the current NE, the NE decides whether to allow the
LCT terminal to log in to it based on the enabling/disabling state of the LCT access function
if some T2000 users already logged in to it. If the LCT access function is disabled, the NE
does not allow the LCT terminal to log in to it. If the LCT access function is enabled, the NE
allows the LCT terminal to log in to it. If you use the LCT terminal to log in to the current
NE, and if no other T2000 users already logged in to it, the NE allows the LCT terminal to
log in to it, regardless of the enabling/ disabling state of the LCT access function.
Procedure
Step 1 Choose File > Search for NE from the Main Menu.
Step 2 Click Modify to display the Input Search Domain dialog box.
Select IP Address Range of GNE. The default address is 129.9.255.255.
Enter the user name, which is ‘lct’ by default.
Enter the password, which is ‘password’ by default.
Step 3 Click OK and close the dialog box.
Step 4 Click Start to display a dialog box.
Step 5 Click OK to start searching for the equipment.

75
Step 6 After the NE is searched out, click Stop. A dialog box is displayed.
Step 7 Click Yes.
Step 8 Select the NE to be created. Click Create. Enter the user name and password in the
displayed dialog box.
User: lct (the default is lct)
lPassword: password (the default is password)
Step 9 Click OK. A dialog box is displayed to prompt that the NE has been created.
Step 10 Click Close.
Step 11 In the NE Information List of the T2000-LCT interface, right-click the created NE
and click
Login. A dialog box is displayed to prompt that the operation succeeds.
Step 12 Click Close.
----End
6.16.5 Configuring NE Commissioning Data:
Some commissioning items require that the data should be configured to the NE. Configure
the NE commissioning data after checking the NE version. This section describes how to
configure the NE commissioning data.
Setting NE ID
After logging in to the NE by using the T2000-LCT, modify the NE ID according to the
actual NE ID planning. This part describes how to set the NE ID by using the T2000-LCT.
The set ID must be line with the ID planning.
Configuration NE name, Date and Time
Use the T2000-LCT to configure the NE name, date and time to make sure that the recorded
and reported alarms and performance events are correct. This section describes how to
configure NE
Name, date and time.
6.16.6 Configuration Services to the NE for Commissioning:
Some commissioning items are based on the configured services. Hence, it is required to
Configure services for commissioning.
6.16.7 Setting NE ID:
After logging in to the NE by using the T2000-LCT, modify the NE ID according to the
actual NE ID planning. This part describes how to set the NE ID by using the T2000-LCT.
The set ID must be line with the ID planning. Choose NE
Explore.
Step 3 Choose Configuration > NE Attribute in the Function Tree.

76
Step 4 Click Modify NE ID and set the NE ID to the value 9. Click OK. The Warning
dialog box is displayed. Click OK.
NOTE:
The extended NE ID can also be modified.
Step 5 Return to NE Information List, and choose the NE whose ID is altered. Right-click
the NE and
Step 6 Choose File > Search for NE from the menu. Click Start. A dialog box is displayed.
Click
OK.
Step 7 Search out the NE whose ID is modified. Click Stop. A dialog box is displayed. Click
Yes.
Step 8 Select the NE to be created. Click Create. Enter the user name and password is in the
displayed
dialog box.
User name: "lct" by default
Password: "password" by default
Step 9 Click OK. A dialog box is displayed to prompt that the NE has been created. Click
Close. In this case, the NE Status field displays created.
Step 10 In NE Information List of the T2000-LCT interface, right-click the created NE and
click Login. A dialog box is displayed to prompt that the operation succeeds. Click Close.
----End
6.16.8 Configuring NE Name, Date and Time:
Use the T2000-LCT to configure the NE name, date and time to make sure that the recorded
and reported alarms and performance events are correct. This section describes how to
configure NE name, date and time.
Prerequisite
The commissioning engineer must have logged in to the NE by using the T2000-LCT client.
NOTE:
The synchronization of NE time does not affect services. Before synchronizing the NE time,
verify that the time of the PC where the T2000-LCT server is installed is correct. If the PC
time needs to be modified, first log out of the T2000-LCT and then set the PC time. Then
restart the T2000-LCT.
Procedure
Step 1 Right-click the NE in NE Information List and choose NE Explorer.
Step 2 Choose Configuration > NE Attribute from the Function Tree.
Step 3 Modify the NE name and click Apply.
NOTE:
The NE name must be of this format: NE ID – Name. For example, 1– Beijing
Step 4 The Operation Result dialog box is displayed to prompt that the operation succeeds.
Click
Close.

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