Amal Report

8/3/2019 Amal Report

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LPUTraining & placement cell

MID-Term Report of 6 Months Training

In

ALCATELLUCENT

(NEW-DELHI)

By

AMAL CHAUDHARY

Submitted in partial fulfillment of the requirement for

Degree of Bachelor of Technology (Electronics & Comm.),

Of

LOVELY PROFESSIONAL UNIIVERSITY

Department of Electronics & communication Engineering,

2011-2012


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PREFACE

To be a perfect engineer, it is necessary to have an idea about the industrial joband must know some basic facts like, how the work is done in Industry? What are the

common problems and how to tackle them? There is great difference between theory and

practical.

Although, we do practical in college but these are not sufficient, as their

industrial environment cannot be created. This can be done by sending students to various

industries, which improves their knowledge and is very helpful in being a good engineer. Due

to these facts LOVELY PROFESSIONAL UNIVERSITY held In-plant Training for 6

Months.

We are pursuing our In-Plant Training at ALCATEL-LUCENT (DELHI) from1 JUNE 2011 in our 7

thsemester.


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Acknowledgement:

This is a great opportunity to acknowledge and to thanks everybody without

whose support and help this In-plant Training would have been impossible. I would like to

add a few heartfelt words for the people who where part of this In-Plant Training in numerous

ways.

I would like to thanks to my training guideSRINIVAS SIR, for providing me

the right ambiance, valuable suggestion, moral support, constant encouragement and

contribution of time for the successful going of our In-plan Training. We are very grateful to

him, for providing all the facilities needed during the training. At the outset, we sincerely

thank all faculty members of my institution for their extra effort to make our session on line

inspire of all ideas.

Needless to say, without all the above help and support our training would not been

a success.

AMAL CHAUDHARY


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CONTENT:

Name Page No.

1. Organization Profile and History 4

2. Joint Venture of Alcatel Lucent 6

3. Services and the Processes: 7

4. Facets of Transport: 8

5. Technology Used for transmission: 9

a. PDH

- PDH (advantage and disadvantage)

c. SDH (origin)

- advantages and disadvantages of SDH

- SDH Topology

- SDH PRINCIPLE

- STM-1

- STM-1 frame

-SDH Concatenation

- Errors in SDH transmission

-Alarms for error indication in SDH


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1. Organisation Profile And History

Alcatel-Lucents vision is to enrich peoples lives by transforming the way the

world communicates. Alcatel-Lucent provides solutions that enable service providers,

enterprises and governments worldwide, to deliver voice, data and video communication

services to end-users. As a leader in fixed, mobile and converged broadband access, carrier

and enterprise IP technologies, applications, and services, Alcatel-Lucent offers the end-to-

end solutions that enable compelling communications services for people at home, at work

and on the move.

With more than 77,000 employees and operations in more than 130 countries, Alcatel-Lucent

is a local partner with global reach. The company has one of the largest research, technology

and innovation organizations focused on communications Alcatel-Lucent Bell Labs and the most experienced global services team in the industry. Alcatel-Lucent achieved

adjusted revenues of Euro 16.98 billion in 2008, and is incorporated in France, with

headquarters in Paris.

OrganizationWith a strong focus on complete solutions maximizing value for customers, Alcatel-Lucent is

organized around four business groups and three geographic regions. The Application

Software Group focuses on developing and maintaining innovative software products for its

global customer base. The Carrier Product Group serves fixed, wireless and convergentservice providers with end-to-end communications solutions. The Enterprise Product Group

focuses on meeting the needs of business customers as well as the Industry & Public Sector.The Services Group designs, deploys, manages and maintains networks worldwide. The

company's geographic regions are the Americas; Europe, Middle East, and Africa; and Asia

Pacific and China.

Innovation & Technology

Alcatel-Lucent is one of the largest innovation powerhouses in the communications industry,

representing an R&D investment of Euro 2.5 billion, and a portfolio of more than 26,000

active patents spanning virtually every technology area. At the core of this innovation is

Alcatel-Lucents Bell Labs, an innovation engine with researchers and scientists at theforefront of research into areas such as multimedia and convergent services and applications,

new service delivery architectures and platforms, wireless and wireline, broadband access,

packet and optical networking and transport, network security, enterprise networking and

communication services and fundamental research in areas such as nanotechnology,

algorithmic, and computer sciences.


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History:

The formation of Alcatel-Lucent created the worlds first truly global communications

solutions provider, with the most complete end-to-end portfolio of solutions and services in

the industry.

Alcatel-Lucent combined two entitiesAlcatel and Lucent Technologieswhich shared a

common lineage dating back to 1986. That was the year Alcatels parent company, CGE (la

Compagnie Gnrale dElectricit), acquired ITTs European telecom business. Nearly 60

years earlier, ITT had purchased most of AT&Ts manufacturing operations outside the

United States. Lucent Technologies was spun off from AT&T.

The combination of Alcatel and Lucent Technologies created the worlds first truly global

communications solutions provider by building on two rich heritages.

Alcatel-Lucent has three regional groups Americas; Europe, Middle East, and Africa; and

Asia Pacific and China - focused on addressing the unique needs of customers throughout the

world.

Alcatel-Lucent Fast Facts:

Alcatel-Lucent (Euronext Paris and NYSE: ALU) provides solutions that enable service

providers, enterprises and governments worldwide, to deliver voice, data and video

communication services to end-users. As a leader in fixed, mobile and converged broadbandnetworking, IP technologies, applications, and services, Alcatel-Lucent offers the end-to-end

solutions that enable compelling communications services for people at home, at work and on

the move. With operations in more than 130 countries, Alcatel-Lucent is a local partner with

global reach. The company has one of the largest research, technology and innovation

organizations focused on communications Alcatel-Lucent Bell Labs and the most

experienced global services team in the industry. Alcatel-Lucent achieved revenues of Euro

16.98 billion in 2008 and is incorporated in France, with headquarters in Paris.

Alcatel-Lucent is aFrenchcompany that provides hardware, software, and services

totelecommunicationsservice providers and enterprises all over the globe. The company is

incorporated inFrance, and has its global executive offices inParis. The company does

business in 132 countries, with almost equal sales distribution coming from both

itsEuropeanandNorth Americanregions, and an additional third of its channellocated

elsewhere in the world. Alcatel-Lucent was formed after Alcatel's buyout ofLucent

TechnologiesonDecember 1,2006.
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2.Joint Venture Of Alcatel-Lucent:

JV will manage Airtels migration to next generation networks (NGN) to offer

advanced services like high-speed internet, triple play, media-rich VAS,

MPLS, VPN for both retail and business customers

First managed services partnership for broadband and telephone services in

India

Paris and New Delhi, April 30, 2009 - Bharti Airtel, Asias leading integrated

telecom service provider, and Alcatel-Lucent (Euronext Paris and NYSE: ALU) today

announced that they have formed a joint venture to manage Bharti Airtels pan-India

broadband and telephone services and help Airtels transition to next generation networks.

Under the joint venture, Alcatel-Lucent will design, plan, deploy, optimize and manage

Bharti Airtels broadband and telephone network across India. A new legal entity is being

formed which will be operated by Alcatel-Lucent.

This managed services partnership will include all end-to-end activities service rollout,

installation and fault repair, service continuity and transformation. It will support BhartiAirtels transformation to next generation networks, offering advanced services like high-

speed internet, triple play, media-rich VAS, MPLS, VPN for both retail and business

customers. The partnership will also drive optimal capital investment and increase

operational efficiency by moving voice and data traffic onto a single, 'packetized'

infrastructure.


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3. Services And The Processes:

The services provided to AIRTEL are on MANAGEMENT OF NETWORKS. Theseservices include transmission of voice,data and voice/ data.The recently launched IPTVby

AIRTEL is basically managed by ALCATEL- LUCENT. The INTERNET SERVICES also

comes under ALCATELLUCENTS management.

As said the MAIN FUNCTION of ALCATEL-LUCENT is to look after voice, data and

voice/data transmission.

Now how exactly this process goes on is stated and explained with the help of the following :

Fig.Challenges of Transport


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4. Means of Transport

1. Media

Wireline Copper , Aluminium

Wireless RF, W ( Electromagnetic) Optical OFC

2. Topology - (Pattern of connecting network element)

Mesh - LocalStar -

Bus - for LAN

Ringfor SDH network

3. Technology

- Voice Communication PDH,- Modern Transport SDH,

- DWDM

4. Network Management

- Network Management Preside


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5. Technology Used for transmission:

Before 1970 most of the worlds telephony systems were based on single line, voice

frequency, connections over twisted copper pair.

In the early 1970s digital transmission systems began to appear using Pulse Code

Modulation (PCM). Alec Reeves of Standard telephone cables (STC) had first proposed this

system of transmission in 1937.

PCM enables analogue waveforms such as speech to be converted into a binary format

suitable for transmission over long distances via digital systems.

PCM works by sampling the analogue signal at regular intervals, assigning a value to the

sample and then transmitting this value as a binary stream.

This process is still in use today and forms the basis of virtually all the transmission systems

that we currently use.

Fig 1.1 PCM Block diagram

Engineers soon saw the potential to produce more effective transmission systems by

combining several PCM channels together over the same copper pair.

In Europe a standard was adopted where thirty-two, 64kbit/s channels were combined

together in a process called "multiplexing", to produce a structure with a transmission

rate of 2.048 Mbit/s (usually referred to as 2 Mbit/s).

As demand for telephony services grew, it soon became apparent that the standard

2 Mbit/s signal was not sufficient to cope with the demands of the growing network, and so afurther level of multiplexing was devised.

Four, 2 Mbit/s signals were combined together to form an 8 Mbit/s signal (actually 8.448

Mbit/s).

As the need arose, additional levels of multiplexing structure were added to include rates of

34 Mbit/s (34.368) and 140 Mbit/s (139.264).

These transmission speeds are called Plesiochronous Digital Hierarchy or PDH rates.

Sampler Quantiser Encoder 01010011

0

1

2

3


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Comparison of hierarchical PDH rates:

Whilst the European hierarchy was being developed a similar system was being devised in

America. Although the same principal was used, a different hierarchical structure was

adopted.

Europe North America

Primary 2.048 Mbit/s Primary 1.544 Mbit/s

8.44 Mbit/s 6.132 Mbit/s

34.368 Mbit/s 44.736 Mbit/s

139.264 Mbit/s

Although each of the systems works fine as a stand-alone hierarchy, it does makeinternational inter-connection very difficult and costly.

This was the major reason for the development of a new internationally agreed

standard.

PDH n Suffix

The PDH rates are often referred to by an n suffix.

This suffix is also used within SDH to refer to the various different PDH input signals.The table below shows these suffixes and there associated rates.

n Suffix Bit rate (Kbit/s)

11 1,544

12 2,048

21 6,312

22 8,448

31 34,36832 44,736

4 139,264


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Disadvantages of PDH networks:

Because of the way that PDH signal is structured, it is impossible to extract a single 2 Mbit/s

signal from within a higher order (say 140 Mbit/s) stream.

Therefore when a 2 Mbit/s signal needs to be cross-connected between one transmissionsystem and another, it must be de-multiplexed back down to its primary rate first. This forms

what is referred to a multiplexer mountain.

As we can see, the multiplexer mountain means that we need to have a lot of expensive

equipment just to connect 2 Megs together.

This means that:

Valuable space is taken up in racks in node sites and more equipment means moremaintenance-associated problems.

Each of the equipment levels is synchronised from a different source and at a differentrate. This can lead to clocking problems that can cause errors.

This equipment must also be jumperd not only at the 2 Mbit/s level for customerinterconnection, but also between the various multiplexers that make up the individual

transmission system. This leads to large amounts of coax wiring, which is physically very

bulky and also relatively high maintenance, due to the fact that the terminating plugs

work on a mechanical nature.

An advantage of PDH is the small overhead of the system. This leads to efficient use ofbandwidth. Unfortunately because of this lack of overhead in the structure, management

facilities in PDH are severely limited:

There is no automatic storage of route information so comprehensive and accuratepaper records must be kept to avoid problems.

34/8

140/

34

8/2

34/8

140/

34

8/2

140 Mbit/sLTE

140 Mbit/sLTE

34 Mbit/s

8 Mbit/s

2 Mbit/s

ADD DROP 2Mbit's Tributary


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There is no ability to remotely configure equipment and the alarm monitoring isrudimentary, effectively only reporting loss of inputs.

Protection of the transmission paths is generally only available using 1+1 protection at thehigher PDH levels i.e.140 Mbit/s and above, leaving customer 2 Mbit/s circuit vulnerable

to failure.

Overview of PDH Limitations:

Interconnection between national (European/North American) systems difficult.

PDH 'multiplexer mountain' is costly and inflexible.

All hierarchy levels are clocked individually, so slips possible.

Protection of paths is at higher rates only.

Management is very limited.

Relatively prone to faults (by today's standards).


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Origins of SDH(Synchronous digital hierarchy):

As can be seen from the previous chapter PDH is a workable but flawed system.

At its conception it used the best available technology and was a giant leap forward in

transmission, but with the advent of silicon chips and integrated microprocessors, customer

demand soon provided the need to introduce a new and better system.

This new system needed to solve the existing limitations of PDH, but also provide for

applications of the future.

The first of the working systems to be introduced was the SYNTRAN (Synchronous

Transmission) system from Bellcore. This was however realy only a development system and

was soon replaced with SONET (Synchronous Optical Network).

Initially SONET could only carry the ANSI (American National Standards Institute) bit rates

i.e. 1.5, 6, 45 Mbit/s.

Since the aim of the project was to provide easier international interconnection, SONET wasmodified to carry the European standard bit rates of 2, 8, 34 & 140 Mbit/s.

In 1989 the ITU-T (International Telecommunications Union - Telecommunication's

standardisation section), published recommendations which covered the standards for SDH.

These were adopted in North America by ANSI (SONET is now thought of as a subset of

SDH), making SDH a truly global standard.

Features and Advantages of SDH :

SDH permits the mixing of the existing European and North American PDH bit rates.

SDH is synchronous. All SDH equipment is based on the use of a single master referenceclock source.

Compatible with the majority of existing PDH bit rates

SDH provides for extraction/insertion, of a lower order bit rate from a higher orderaggregate stream, without the need to de-multiplex in stages.

SDH allows for integrated management using a centralised network control.

SDH provides for a standard optical interface thus allowing the inter-working of differentmanufacturers equipment.

Increase in network reliability due to reduction of necessary equipment/jumpering.


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Basic SDH Network Topology:

SDH networks are usually deployed in protected rings. This has the advantage of giving

protection to the data, by providing an alternate route for it to travel over in the event of

equipment or network failure.

Each side of the ring (known as A and B, or sometimes, East and West), consists of an

individual transmit and receive fibre. These fibres will take diverse physical paths to the

distant end equipment to minimise the risk of both routes failing at the same time.

The SDH equipment can detect when there is a problem and will automatically switch to the

alternate route.

To speed up switching times, although SDH multiplexers transmit on both sides of the

ring simultaneously, they only receive on one side at any time. This means that only the

receiving end needs to switch, thus reducing the impact of a fault on the customers' data.

"Fibre break on the Ring -Customer B Switches"

RX

TX

TX

RX

A

A

B

BCustomer A Customer B

"Ring Normal"

RX

TX

TX

RX

A

A

B

BCustomer A Customer B


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SDH Principles:

Overview

The SDH standard defines a number of 'Containers' each corresponding to an existing PDH

input rate. Information from the incoming PDH signal is placed into the relevant container.

Each container then has some control information known as the 'Path Overhead' (POH) and

stuffing bits added to it. The path overhead bytes allow the system operator to achieve end to

end monitoring of areas such as error indication, alarm indication and performance

monitoring data. Together the container and the path overhead form a 'Virtual Container'

(VC).

Due to clock phase differences, the start of the customers' PDH data may not coincide with

the start of the SDH frame. Identification of the start of the PDH data is achieved by adding a

'Pointer'.

The VC and its relevant pointer together form a 'Tributary Unit' (TU).

Tributary units are then multiplexed together in stages (Tributary User Group 2 (TUG-2) -

Tributary User Group 3 (TUG-3) - Virtual Container 4 (VC-4)), to form an

Administrative Unit 4 (AU-4). Additionalstuffing, pointers and overheads are added during

this procedure.

This AU-4 in effect contains 63 x 2 Mbit/s channels and all the control information that is

required.

Finally, Section Overheads (SOH) are added to the AU-4.

These SOH's contain the control bytes for the STM-1 section comprising of framing, section

performance monitoring, maintenance and operational control information.An AU-4 plus its SOH's together form an STM-1 transport frame.

STM Hierarchy and Container Bit Rates

The first hierarchy level for SDH is set at 155,520 kbit/s/s.

This is known as a Synchronous Transport Module 1 (STM-1).Higher levels are simply multiples of the first level, which are denoted by the number after

the -

At present the SDH hierarchy is as follows:

STM-1: 155,520 kbit/s. (155 Mbit/s)

STM-4: 622,080 kbit/s. (620 Mbit/s)

STM-16: 2,488,320 kbit/s. (2.5 Gbit/s)

STM-64: 9,953,280 kbit/s. (10 Gbit/s)


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STM-1:

The STM-1 (Synchronous Transport Module level-1) is the SDH ITU-T fiber optic

networktransmission standard. It has a bit rate of 155.52 Mbit/s. The other levels areSTM-4,

STM-16 and STM-64. Beyond this we have wavelength-division multiplexing (WDM)commonly used in submarine cabling.

Frame structure:

'The STM-1 frame is the basic transmission format for SDH' . A STM-1 signal has a byte-oriented structure with 9 rows and 270 columns of bytes with a total of 2430 bytes (9 rows *

270 columns = 2430 bytes). Each byte corresponds to a 64kbit/s channel.

The frame consists of two parts, the transport overhead and the path virtual envelope (virtual

container with a(VC-4) capacity).

Transport overhead

RSOH: Regenerator Section OverHead.

MSOH: Multiplex Section OverHead.

Frame characteristics

The STM-1 base frame is structured with the following characteristics:

- Length : 270 column x 9 row = 2430 bytes

- Duration(Frame repetition time): 125 s i.e. 8000 frames/s

- Rate (Frame capacity): : 2430 x 8 x 8000 = 155.520 Mbit/s

- Payload = 2340 bytes i.e. 149.760 Mbit/s

1 byte i.e. 64 kbit/s (e.g. speech channel)

STM-1 Frame Structure

The STM-1 transport frame has a duration of 125s. It contains 2430 bytes of information.Each byte contains 8 data bits (i.e. a 64kbit/s channel).

The number of frames per second is 1 second 125s = 8000 Frames per second.

Therefore the rate transmitted to line is: -

8 bits x 2430 bytes x 8000 per second = 155,520,000 bits/s or 155 Mbit/s.

As each frame consists of 2430 bytes, this would prove very difficult to show as a diagram on

a page. To get round this, we show the frame chopped up into 9 segments, stacked on top ofeach other as shown in the diagram below.
http://en.wikipedia.org/wiki/Synchronous_Digital_Hierarchyhttp://en.wikipedia.org/wiki/Synchronous_Digital_Hierarchyhttp://en.wikipedia.org/wiki/ITU-Thttp://en.wikipedia.org/wiki/ITU-Thttp://en.wikipedia.org/wiki/Fiber_optichttp://en.wikipedia.org/wiki/Fiber_optichttp://en.wikipedia.org/wiki/Telecommunications_networkhttp://en.wikipedia.org/wiki/Telecommunications_networkhttp://en.wikipedia.org/wiki/STM-4http://en.wikipedia.org/wiki/STM-4http://en.wikipedia.org/wiki/STM-4http://en.wikipedia.org/wiki/Wavelength-division_multiplexinghttp://en.wikipedia.org/wiki/Wavelength-division_multiplexinghttp://en.wikipedia.org/wiki/Wavelength-division_multiplexinghttp://en.wikipedia.org/wiki/STM-4http://en.wikipedia.org/wiki/Telecommunications_networkhttp://en.wikipedia.org/wiki/Fiber_optichttp://en.wikipedia.org/wiki/ITU-Thttp://en.wikipedia.org/wiki/Synchronous_Digital_Hierarchy


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The bits start at the top left with byte number one and are read from left to right andtop to bottom. They are arranged as 270 columns across and 9 rows down.

Therefore byte 270 is the byte in column 270, row 1. Byte 271 is in column 1, row 2 and byte

2430 is located at column 270, row 9 etc.

STM-1 FRAME SHOWN IN FIGURE:

SOH

AU PTR's

SOH

VC-4 PayloadPO

H

1 9 10 270

270 Columns (bytes)

1

345

9

9

R

o

ws


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SDH Concatenation:

The SDH frame can be thought of as an articulated lorry. The data to be transported is placed

in the VC-4 'Container'. This is then hitched to the SOH 'Cab unit' that 'drives' the data to its

destination.

The maximum carrying capacity of the vehicle is determined by the size of the 'container'.

Thereforealthough the SDH signal is 155 Mbit/s in size, the largest single circuit that

can be transmitted at any one time by the customer is limited to the size of the VC-4 i.e.

140 Mbit/s.

When using higher rates of SDH (STM-4, STM-16 etc), multiple 'containers' and 'cabs' are

added one after another, to form a bigger vehicle. The customer is still limited to a single

circuit size of 140 Mbit/s however, because each individual 'container' is still the same size(140 Mbit/s). They can however transmit multiple 140 Mbit/s circuits simultaneously.

The diagram below represents the standard STM-4 structure

This limitation of 140 Mbit/s per individual circuit is not a particularly efficient way ofmanaging bandwidth and a method ofcombining 'containers'together has been developed

which is called 'Concatenation'.

The diagram below represents an STM-4 concatenated structure (VC-4-4C).

155 M/bits SDH Frame

140 M/bits Payload

VC-4 Payload

SOH

VC-4 Payload VC-4 Payload VC-4 Payload VC-4 Payload

SOH SOH SOH SOH

VC-4 Payload

SOH


20/21

Concatenated paths are commonly defined as VC-4-xC circuits (where x is size of the

concatenation), as shown below:

STM-4 concatenation (written as VC-4-4c), provides a single circuit with a bit rate ofapproximately 600M (actually 599.04 Mbit/s)

STM-16 concatenation (written as VC-4-16c), provides a single circuit with a bit rate ofapproximately 2.2G (actually 2.2396160 Gbit/s)

STM-64 concatenation (written as VC-4-64c), provides a single circuit with a bit rate ofapproximately 10G (actually 9.584640 Gbit/s)

STM-256 concatenation (written as VC-4-256c), provides a single circuit with a bit rateof approximately 38G (actually 38.338560 Gbit/s)

Errors when transmitting data in SDH:

Transmission in SDH network is mainly optical.Optical transmission is not as

sensitive as electrical.Fiber optics has fewer interaction with environment thanelectrical cable, where many cables can be coupled, fiber optics has any how

errors caused by its physical characterstics such as; attenuation in fiber optics

cable, absorption, scattering,distortion in optical signal.

The greatest threat is anyhow is the break of the fibre.

When a cable break or similar to it happens, SDH networks reroutes all traffic

in few milliseconds. SDH frame provides the information of what to do if the

frame does not reach the recipient. These information is divided into well

defined bytes. The most common instruction at the time of break of the cable is

to go back to the same route and try to reach the end point using different route.When the re-routing is done the add and drop multiplexer notices the re-rout

frame and it commands to switch to change all the data going through this nonfunctioning line to the alternating route.


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ALARMS in SDH Networks:

Some important alarms in SDH Networks are explained next. SDH equipment

are set to alarms if some specified errors occur.

1. LOS (loss of signal) :

LOS alarms is given if the SDH equipment notices that the signal level is

Below the specification, usually so low that the information is not

separated from noise, there is also usually a measurement in network forboth optical and electrical power depending on the transmission medium.

2. LOF (loss of frame):

When the SDH networks cannot receive correct frame byte, network

element defines the frame lost. Los alarm is given only if the frame bytesare incorrect during the certain time. When the network element

recognizes the correct byte again the alarm is removed.

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