PROJECT REPORT ON STM-1

Project report submitted in partial fulfillment of the requirements For the award of the degree of

BACHELOR OF TECHNOLOGYINELECTRONICS AND COMMUNICATION ENGINEERINGBy

Under the guidance of

Mr. R.S SANDHU(DE)

INDEX

1. INTRODUCTION TO OPTICAL FIBER CABLE2. TRANSMISSION SEQUENCE3. PRINCIPLE OF FIBER OPTICS4. PROPAGATION OF LIGHT THROUGH FIBER5. CABLE CONSTRUCTION6. ADVANTAGES OF FIBER OPTICS7. APPLICATIONS OF FIBER OPTICS IN COMMUNICATION8. SPLICING9. TRANSMISSION10. OVERVIEW OF SDH11. STM-1 HARDWARE SIEMENS12. MOTHERBOARD SLOT13. IC1.1-2G CARD14. 4E/FE CARD15. E3DS3 CARD

OPTICAL FIBER CABleIn transmission signal can be transmitted from one place to another place through a medium and that medium can be wireline or wireless.Maximum transmission is done by the wireline and about 10% is done by wireless.The wires used are:a. Copper wireb. Optical fiberBut,Optical fiber is most widely used because it has many advantages as compared to copper wire.The main advantage to use fiber is that it has minimum losses instead of copper.Also the fibers are immune to electromagnetic interference.

An optical fiber is a glass or plastic fiber that carries light along its length.. Optical fibers are widely used in fiber-optic communications, which permits transmission over longer distances and at higher data rates (bandwidth) than other forms of communications. Fibers are used instead of metal wires because signals travel along them with less loss, and they are also immune to electromagnetic interference. Fibers are also used for illumination, and are wrapped in bundles so they can be used to carry images, thus allowing viewing in tight spaces. Specially designed fibers are used for a variety of other applications, including sensors and fiber lasers.

ADVANTAGES OF FIBEROPTICS : Optical Fiber are non- conductive (Dielectrics) Electromagnetic Immunity. Large Bandwidth (> 5.0 GHz for 1 km length) Low Loss (5 dB/km to < 0.25 dB/km typical) Small, light- weight cables. Available in Long lengths (> 12 kms) Security Universal medium(i.e. serve all comm. Needs ,Non obsolescence)APPLICATIONS OF FIBER OPTICS IN COMMUNICATION : Common carrier nationwide networks. Telephone Inter-office Trunk lines. Customer premise communication networks. Undersea cables. High EMI areas (Power lines, Rails, Roads). Factory communication/ Automation. Control systems. Expensive environments. High lightening areas. Military applications Classified (secure communication)

PRINCIPLE OF FIBEROPTICS

Total Internal Reflection:- The Reflection that Occurs when a LightRay Travelling in One Material hits a Different Material and Reflects Back into the Original Material without any Loss of Light.

Speed of light is actually the velocity of electromagnetic energy in vacuum such as space. Light travels at slower velocities in other materials such as glass. Light travelling from one material to another changes speed, which results in light changing its direction of travel. This deflection of light is called Refraction.The amount that a ray of light passing from a lower refractive index to a higher one is bent towards the normal. But light going from a higher index to a lower one refracting away from the normal.

PROPAGATION OF LIGHT THROUGH FIBER

The optical fibre has two concentric layers called the core and the cladding. The inner core is the light carrying part. The surrounding cladding provides the different refractive index that allows total internal reflection of light through the core. The index of the cladding is less than 1%,which is lower than that of the core.For example the refractive index of core is 1.47db and cladding is 1.46db. Fiber manufacturers control this difference to obtain desired optical fiber characteristics.

The specific characteristics of light propagation through a fibre depends on many factors, including The size of the fibre. The composition of the fibre. The light injected into the fibre

TRANSMISSION sources: Information is Encoded into Electrical Signals. Electrical Signals are Coverted into light Signals. Light Travels Down the Fiber. A Detector Changes the Light Signals into Electrical Signals. Electrical Signals are Decoded into Information.

LOSSES IN FIBER

ATTENUATION

Attenuation is defined as the loss of optical power over a set distance, a fibre with lower attenuation will allow more power to reach a receiver than fibre with higher attenuation. Attenuation may be categorized as intrinsic or extrinsic.INTRINSIC ATTENUATIONIt is loss due to inherent or within the fibre. Intrinsic attenuation may occur as Absorption - Natural Impurities in the glass absorb light energy. Scattering - Light rays travelling in the core reflect from small imperfections into a new pathway that may be lost through the cladding.EXTRINSIC ATTENUATIONIt is loss due to external sources. Extrinsic attenuation may occur as Macrobending - The fibre is sharply bent so that the light travelling down the fibre cannot make the turn & is lost in the cladding. Microbending - Microbending or small bends in the fibre caused by crushing contraction etc. These bends may not be visible with the naked eye.Attenuation is measured in decibels (dB). A dB represents the comparison between the transmitted and received power in a system.

DISPERSIONDispersion is the spreading of light pulse as its travels down the length of an optical fibre. Dispersion limits the bandwidth or information carrying capacity of a fibre

Colour Coding:Fiber NoColour1 BLUE2 ORANGE3 GREEN4 BROWN5 SLATE6 WHITE7 RED8 BLACK9 YELLOW10 VIOLET11 PINK12 AQUA

EIA598-A FiberColor Chart[13]

PositionJacket colorPositionJacket color

1blue

2orange

3green

4brown

5slate

6white

7red

8black

9yellow

10violet

11rose

12aqua

CABLE CONSTRUCTION

An optical fiber cable is a cable containing one or more optical fibers. The optical fiber elements are typically individually coated with plastic layers and contained in a protective tube suitable for the environment where the cable will be deployed

Fiber optic cables have the following parts:

Optical fiber Buffer Strength member Jacket

I. Buffer:It is made up of Nylone,Mylar or Plastic and it protects fiber from outside.II. Strength member:It adds mechanical strength to the fiber.During and after installation,the strength member handle the tensile stresses applied to the cable so that the fiber is not damaged.III. Jacket:It provides protection from the effects of oil,ozone,acids etc.The choice of jacket material depends on degree of resistance required for different influences.

PolymerRibsOptical fibercableOfc tubesThreadsJacketStrength member

SPLICING

Splices are permanent connection between two fibers. The splicing involves cutting of the two fibers to be spliced.Splicing MethodsThe following three types are widely used 1. Chemical splicing (Adhesive Bonding or Glue Splicing)2. Mechanical splicing.3. Fusion splicing.1.Adhesive Bonding or Glue SplicingThis is the oldest splicing technique used in fibre splicing. Cylindrical rods or another kind of reference surfaces are used for alignment. During the alignment of fibre end, a small amount of adhesive or glue of same refractive index as the core material is set between and around the fibre ends. A two component epoxy or an UV curable adhesive is used as the bonding agent. The splice loss of this type of joint is same or less than fusion splices. But fusion splicing technique is more reliable, so at present this technique is very rarely used. 2. Mechanical SplicingThis technique is mainly used for temporary splicing in case of emergency repairing. This method is also convenient to connect measuring instruments to bare fibres for taking various measurements. The mechanical splice consist of four basic components:i. An alignment surface for mating fiber endsii. A retaineriii. An index matching materialiv. A protective housing

3.Fusion Splicing:The fusion splicing technique is the most popular technique used for achieving very low splice losses. The fusion can be achieved either through electrical arc or through gas flame. The process involves cutting of the fibres and fixing them in micropositioners on the fusion splicing machine. The fibres are then aligned either manually or automatically core aligning process. Afterwards the operation that takes place involve withdrawal of the fibres to a specified distance, preheating of the fibre ends through electric arc and bringing together of the fibre ends in a position and splicing through high temperature fusion. If proper care taken and splicing is done strictly as per schedule, then the splicing loss can be minimized as low as 0.01 dB/joint. After fusion splicing, the splicing joint should be provided with a proper protector to have following protections Mechanical protectionProtection from moisture.

Optic Fiber Cable SplicingTwo optical fiber splicing methods are available for permanent joining of two optical fibers. Both methods provide much lower insertion loss compared to fiber connectors.1. Fiber optic cable fusion splicing Insertion loss < 0.1dB 2. Fiber mechanical splicing Insertion loss < 0.5dB Operation of fiber splicing:1. Strip2. Clean3. Cleave

1.Strip:Strip the fiber according to its length.

2.Clean:Now,clean the fiber with a tissue. 3.Cleave:Place the fiber in the cleaver.

Load the splicer:

High precision fusion splicers are usually bulky and expensive. With proper training, a fiber splicing technician can routinely achieve less than 0.1dB insertion loss splicing for both single mode and multimode fiber cables.Fiber optic cable splicing procedure (How to splice fiber optic cable)1. Strip fiber cable jacket: Strip back about 3 meters of fiber cable jacket to expose the fiber loose tubes or tight buffered fibers. Use cable rip cord to cut through the fiber jacket. Then carefully peel back the jacket and expose the insides. Cut off the excess jacket. Clean off all cable gel with cable gel remover. Separate the fiber loose tubes and buffers by carefully cutting away any yarn or sheath. Leave enough of the strength member to properly secure the cable in the splice enclose. 2. Strip fiber tubes. For a loose tube fiber cable, strip away about 2 meters of fiber tube using a buffer tube stripper and expose the individual fibers. 3. Clean cable gel. Carefully clean all fibers in the loose tube of any filling gel with cable gel remover. 4. Secure cable tubes. Secure the end of the loose tube to the splice tray and lay out cleaned and separated fibers on the table. Strip and clean the other cable tubes fiber that is to be spliced, and secure to the splice tray. 5. Strip first splicing fiber. Hold the first splicing fiber and remove the 250um fiber coating to expose 5cm of 125um bare fiber cladding with fiber coating stripper tool. For tight buffered fibers, remove 5cm of 900um tight buffer first with a buffer stripping tool, and then remove the 5cm of 250um coating. 6. Place the fusion splice protection sleeve. Put a fusion splice protection sleeve onto the fiber being spliced. 7. Clean the bare fiber. Carefully clean the stripped bare fiber with lint-free wipes soaked in isopropyl alcohol. After cleaning, prevent the fiber from touching anything. 8. Fiber cleaving. With a high precision fiber cleaver, cleave the fiber to a specified length according to your fusion splicers manual. 9. Prepare second fiber being spliced. Strip, clean and cleave the other fiber to be spliced. 10. Fusion splicing. Place both fibers in the fusion splicer and do the fusion splice according to its manual. 11. Heat shrink the fusion splice protection sleeve. Slide the fusion splice protection sleeve on the joint and put it into the heat shrink oven, and press the heat button. 12. Place splice into splice tray. Carefully place the finished splice into the splice tray and loop excess fiber around its guides. Ensure that the fibers minimum bending radius is not compromised.

SPLICING MACHINE

TRANSMISSION

In transmission signal can be transmitted from one place to another place through a medium and that medium can be wireline or wireless.Maximum transmission is done by the wireline and about 10% is done by wireless.

MULTIPLEXING: The techniques used to provide a number of circuits using a single transmission link is called Multiplexing.MULTIPLEXING TECHNIQUESThere are basically two types of multiplexing techniques Frequency Division Multiplexing (FDM) Time Division Multiplexing (TDM)

Frequency Division Multiplexing Techniques (FDM) The FDM techniques is the process of translating individual speech circuits (300-3400 Hz) into pre-assigned frequency slots within the bandwidth of the transmission medium. The frequency translation is done by amplitude modulation of the audio frequency with an appropriate carrier frequency. At the output of the modulator a filter network is connected to select either a lower or an upper side band. Since the intelligence is carried in either side band, single side band suppressed carrier mode of AM is used. This results in substantial saving of bandwidth mid also permits the use of low power amplifiers.

Time Division Multiplexing(TDM) Time division multiplexing involves nothing more than sharing a transmission medium by a number of circuits in time domain by establishing a sequence of time slots during which individual channels (circuits) can be transmitted. Thus the entire bandwidth is periodically available to each channel. Normally all time slots1 are equal in length. Each channel is assigned a time slot with a specific common repetition period called a frame interval.

SYNCHRONIZATION The output of a PCM terminal will be a continuous stream of bits. At the receiving end, the receiver has to receive the incoming stream of bits and discriminate between frames and separate channels from these. That is, the receiver has to recognise the start of each frame correctly. This operation is called frame alignment or Synchronization and is achieved by inserting a fixed digital pattern called a "Frame Alignment Word (FAW)" into the transmitted bit stream at regular intervals. The receiver looks for FAW and once it is detected, it knows that in next time slot, information for channel one will be there.

In a 30 chl PCM system, time slot Ts 16 in each frame is allocated for carrying signaling information.The time slot of 16 of each frame carries the signaling data corresponding to two VF channels only. Therefore, to cater for 30 channels, we must transmit 15 frames, each having 125 microsecond duration. For carrying synchronization data for all frames, one additional frame is used. Thus a group of 16 frames (each of 125 microseconds) is formed to make a "multiframe". The duration of a multiframe is 2 milliseconds. The multiframe has 16 major time slots (frames) of 125 microseconds duration. Each of these (slots)/frames has 32 time slots carrying, the encoded samples of all channels plus the signaling and synchronization data. Each sample has eight bits of duration 0.400 microseconds (3.9/8 = 0.488) each.

A 30 channel PCM system has 2048 K bits:The total number of bits per frame = 32 x 8 = 256The total number of frames per seconds is 8000The total number of bits per second are 256 x 8000 = 2048 K/bits.

DIGITAL HIERARCHIES BASED ON THE 1544 KBIT/S PCM PRIMARY MULTIPLEX EQUIPMENTIt was around 1968 that Bell Labs proposed a digital hierarchy based on the 24-channel PCM primary multiplex at the various levels of the hierarchy: Level in hierarchyBit rateTrans. line

First level1544 kbit/sT1

Second level6312 kbit/sT2

Third level46304 kbit/sL5 (Jumbo Grp)

Fourth level280000 kbit/sWT4 (Wave guide)

Fifth level568000 kbit/sT5

DIGITAL HIERARCHY BASED ON THE 2048 KBIT/S PCM PRIMARY MULTIPLEX EQUIPMENTFor this digital hierarchy, two specifications have at present been laid down only for the first level at 2048 kbit/s and for the second level at 8448 kbit/s. As for the higher levels, the situation is just contrary to that existing in the case of digital hierarchies derived from 1544 kbit/s primary multiplex, i.e. general agreement has more or less been reached on the fourth level having a bit rate of 139264 kbit/s. 5th order system where bit rate of 565 Mb/s have also been planned now. he critical point in this hierarchy is whether or not the third level at 34368 kbit/s should exist.Encoded TDM (European)

4th order bit rate of 139264 kbit/s in the digital hierarchy which is based on the 2nd order bit rate of 8448 kbit/s. Realization by separate digital multiplex equipments : one type which operates at 34368 kbit/s and multiplexes four digital signals at 8448 kbit/s; the other type which operates at 139264 kbit/s and multiplexes four digital signals at 34368 kbit/s.

Where the fifth level is concerned, some preliminary proposals (e.g. 565148 kbit/s) have been submitted which were not discussed in detail. DIGITAL MULTIPLEXING HIERARCHYThe functions of digital multiplex equipment are to combine a defined integral number of digital input signals (called tributaries) at a defined digit rate by time division multiplexing and also to carry out the reverse process (de-multiplexing).In analogue system, multiplex equipment uses F.D.M. to assemble individual channels into groups, super group etc. Similarly, in digital systems, hierarchical levels have been defined using T.D.M. and are identified by their digit rate measured in bit/sec. Bit rate Mb/SNo. of channels

2.04830

8.448120

34.368480

139.264 1920

MULTIPLEXING OF DIGITAL SIGNALSThe digital signals which are to be multiplexed may be synchronous to one clock (called master clock) or they may not be synchronous (called asynchronous signals).MULTIPLEXING OF SYNCHRONOUS DIGITAL SIGNALSThe various tributary bit streams are synchronous and operate at the same rate defined as T bit/sec. To multiplex n such tributaries the rate of multiplex output should be nT bit/s. The method adopted for multiplexing such n signals into one stream may be as follows: Block interleaving :Bunch of information taken at a time from each tributary and fed to main multiplex output stream. The memory required will be very large. Bit interleaving :A bit of information taken at time from each tributary and fed to main multiplex output stream in cyclic order, a very small memory is required. At the de-multiplex end, it is necessary to recognise which bit of information belongs to which tributary. This could be achieved by transmitting a fixed code after a fixed number of information bits called frame. The fixed code is called frame alignment signal. It is recognised first and received frame of information is aligned to this fixed code. This method of multiplexing is easy but not reliable. If any deviation in nominal bit rate of a tributary occurs, it will cause loss of time slot and hence loss of information.

MULTIPLEXING OF ASYNCHRONOUS SIGNAL Here, various tributaries operate at different bit rates. Two signals are asynchronous at their corresponding significant instant occur at nominally the same rate, any variation in rate being constrained within specified limits. When nominal bit rate of tributaries are within specified limit it is necessary to synchronize the tributary signal with a common nominal bit rate of multiplexer derived from timing generator of multiplexer. The synchronization is done in such a way that there is no loss of information

139.264 Therefore, the present structure of this digital hierarchy is as given

OVERVIEW OF SDHIt is an international standard for high speed telecommunication over optical/electrical networks ,can transport digital signals.SYNCHRONOUS : One master clock and all elements synchronise with it.DIGITAL: Information in binary.HIERARCHY: Set of bit rates in a hierarchical order.1988 SDH standard introduced with three major goals Avoid the problems of PDH Achieve higher bit rates (Gbit/s) Better means for Operation, Administration, and Maintenance (OA&M)SDH is an ITU-T standard for a high capacity telecom network. SDH is a synchronous digital transport system, aim to provide a simple, economical and flexible telecom infrastructure. The basis of Synchronous Digital Hierarchy (SDH) is synchronous multiplexing - data from multiple tributary sources is byte interleaved.ADVANTAGES High transmission rates:Transmission rates of up to 40 Gbit/s can be achieved in modern SDH systems. SDH is therefore the most suitable technology for backbones, which can be considered as being the super highways in today's telecommunications networks. Simplified add & drop functionCompared with the older PDH system, it is much easier to extract and insert low-bit rate channels from or into the high-speed bit streams in SDH. It is no longer necessary to demultiplex and then remultiplex the plesiochronous structure. High availability and capacity matchingWith SDH, network providers can react quickly and easily to the requirements of their customers. For example, leased lines can be switched in a matter of minutes. The network provider can use standardized network elements that can be controlled and monitored from a central location by means of a telecommunications network management (TMN) system. ReliabilityModern SDH networks include various automatic back-up and repair mechanisms to cope with system faults. Failure of a link or a network element does not lead to failure of the entire network which could be a financial disaster for the network provider. These back-up circuits are also monitored by a management system. Future-proof platform for new servicesRight now, SDH is the ideal platform for services ranging from POTS, ISDN and mobile radio through to data communications (LAN, WAN, etc.), and it is able to handle the very latest services, such as video on demand and digital video broadcasting via ATM that are gradually becoming established. InterconnectionSDH makes it much easier to set up gateways between different network providers and to SONET systems. The SDH interfaces are globally standardized, making it possible to combine network elements from different manufacturers into a network. The result is a reduction in equipment costs as compared with PDH.Applications:The mixture of different applications is typical of the data transported by SDH. Synchronous networks must be able to transmit plesiochronous signals and at the same time be capable of handling future services such as ATM. Current SDH networks are basically made up from four different types of network element. The topology (i.e. ring or mesh structure) is governed by the requirements of the network provider. RegeneratorsRegenerators as the name implies, have the job of regenerating the clock and amplitude relationships of the incoming data signals that have been attenuated and distorted by dispersion. They derive their clock signals from the incoming data stream. Messages are received by extracting various 64 kbit/s channels (e.g. service channels E1, F1) in the RSOH (regenerator section overhead). Messages can also be output using these channels. Terminal Multiplexer Terminal multiplexers Terminal multiplexers are used to combine plesiochronous and synchronous input signals into higher bit rate STM-N signals. Add/drop Multiplexers(ADM) Add/drop multiplexers (ADM) Plesiochronous and lower bit rate synchronous signals can be extracted from or inserted into high speed SDH bit streams by means of ADMs. This feature makes it possible to set up ring structures, which have the advantage that automatic back-up path switching is possible using elements in the ring in the event of a fault. Digital Cross-connectDigital cross-connects (DXC) This network element has the widest range of functions. It allows mapping of PDH tributary signals into virtual containers as well as switching of various containers up to and including VC-4.Network Element ManagerThe telecommunications management network (TMN) is considered as a further element in the synchronous network. All the SDH network elements mentioned so far are software-controlled. This means that they can be monitored and remotely controlled, one of the most important features of SDH. Network management is described in more detail in the section TMN in the SDH networkSDH RatesSDH is a transport hierarchy based on multiples of 155.52 Mbit/s STM-1 = 155.52 Mbit/s STM-4 = 622.08 Mbit/s STM-16 = 2588.32 Mbit/s STM-64 = 9953.28 Mbit/s

SDH HIERARCHYSDH defines a multiplexing hierarchy that allows all existing PDH rates to be transported synchronously.The following diagram shows these multiplexing paths.

(GENERALIZED MULTIPLEXING STRUCTURE/G.708)Container: Information structure unit that carries service signals at different rates. G.709 defines the criteria for five standard containers: C-11, C-12, C-2, C-3 and C-4. Virtual container (VC): Information structure unit supporting channel layer connection of SDH. It terminates an SDH channel. VC is divided into lower-order and higher-order VCs. VC-4 and VC-3 in AU-3 are higher-order virtual containers. Tributary unit (TU) and tributary unit group (TUG): TU is the information structure that provides adaptation between higher-order and lower-order channel layers. TUG is a set of one or more TUs whose location is fixed in higher-order VC payload. Administrative unit (AU) and administrative unit group (AUG): AU is the information structure that provides adaptation between higher-order channel layer and multiplex section layer. AUG is a set of one or more AUs whose locations are fixed in the payload of STM-N.

The Container (C) Basic packaging unit for tributary signals (PDH) Synchronous to the STM-1 Bitrate adaptation is done via a positive stuffing procedure Adaptation of synchronous tributaries by fixed stuffing bits Bit by bit stuffing The Virtual Container (VC) Formation of the Container by adding of a POH (Path Overhead) Transport as a unit through the network (SDH) A VC containing several VCs has also a pointer area The Tributary Unit (TU) Is formed via adding a pointer to the VC The Tributary Unit Group (TUG) Combines several TUs for a new VC The Administrative Unit (AU) Is shaped if a pointer is allocated to the VC formed at last The Syncronous Transport Module Level 1 (STM-1) Formed by adding a Section Overhead (SOH) to AUs Clock justification through positive-zero-negative stuffing in the AU pointer area byte by byte stuffing It is an information structure which provides adaptation between two layers: Between lower and higher order path layers for TUBetween higher order path layer and section layer for AU

Pointer is an indicator whose value defines the frame offset of a VC withrespect to the frame reference of the transport entity on which it is supported

STM-1 HARDWARE(SIEMENS)STM stands for Synchronous Transport Module.This is the information structure used to support information payload and over head information field organised in a block frame structure which repeats every 125 microseconds.The bit rate of STM-1 is 155.520Mbps.

Shelf View of STM-1 System

FRAME FORMATThe standardized SDH transmission frames, called Synchronous Transport Modules of Nth hierarchical level (STM-N).A frame with a bit rate of 155.52 Mbit/s is defined in ITU-T RecommendationG.707. This frame is called the synchronous transport module (STM). Since the frame is the first level of the synchronous digital hierarchy, it is known as STM-1. Figure 2 shows the format of this frame. It is made up from a byte matrix of 9 rows and 270 columns. Transmission is row by row, starting with the byte in the upper left corner and ending with the byte in the lower right corner. The frame repetition rate is 125 ms., each byte in the payload represents a 64 kbit/s channel. The STM-1 frame is capable of transporting any PDH tributary signal.The first 9 bytes in each of the 9 rows are called the overhead. G.707 makes a distinction between the regenerator section overhead (RSOH) and the multiplex section overhead (MSOH). The reason for this is to be able to couple the functions of certain overhead bytes to the network architecture. The table below describes the individual functions of the bytes.

Figure 2.4 STM-1 frame formatSECTION OVERHEADSRSOH (regenerator section overhead) The Regenerator Section OverHead uses the first three rows & nine columns in the STM-1 frame

A1, A2The Frame Alignment Word is used to recognize the beginning of an STM-N frameJ0 Path Trace. It is used to give a path through an SDH Network a "Name". This message (Name) enables the receiver to check the continuity of its connection with the desired transmitterB1 Bit Error Monitoring. The B1 Byte contains the result of the parity check of the previous STM frame, before scrambling of the actual STM frame. This check is carried out with a Bit Interleaved Parity check.E1Engineering Orderwire (EOW). It can be used to transmit speech signals beyond a Regenerator Section for operating and maintenance purposesF1 User Channel. It is used to transmit data and speech for service and maintenanceD1 to D3 Data Communication Channel at 192 kbit/s (DCCR). This channel is used to transmit management information via the STM-1 framesMSOH (multiplex section overhead)The Multiplex Section OverHead uses the 5th through 9th rows, and first 9 columns in the STM-1 frame.B2 Bit Error Monitoring. The B2 Bytes contains the result of the parity check of the previous STM frame, except the RSOH, before scrambling of the actual STM frame. This check is carried out with a Bit Interleaved Parity check (BIP24)K1, K2 Automatic Protection Switching (APS). In case of a failure, the STM frames can be routed new with the help of the K1, K2 Bytes through the SDH Network. Assigned to the multiplexing section protection (MSP) protocolK2 (Bit6,7,8) MS_RDI Multiplex Section Remote Defect Indication (former MS_FERF Multiplex Section Far End Receive Failure) D4 to D12 Data Communication Channel at 576 kbit/s (DCCM).

SIEMENS:

COMPACT 155 MBIT/SADD-DROP MULTIPLEXERSURPASS hiT-1/4E P5.3

The SURPASS hiT-1/4E is an optical STM-1/STM-4 add-drop multiplexer used to build STM-1/STM-4 point-to-point links, STM-1 or STM-4 rings, or mesh networks with conduct (SNC) orSTM-1 line (MSP) protection, so performing the conveyance of 2 Mbit/s, 34 or 45 Mbit/s PDHlinks, of155 Mbit/s STM-1 SDH links, of 10/100 Mbit/s Ethernet links.From P5.3 release, the STM-1 cards offer extractable interfaces SFP (Small Form FactorPluggable), also integrating DDM (DIGITAL Diagnostic Monitoring) function.The SURPASS hiT-1/4E can be used as : STM-1 terminal multiplexer with maximum capacity of 63 VC12 and capability of 1+1 protection, STM-1 repeater, capability of regenerating 2 VC4, STM1 multiplexer with insertion/extraction, with maximum capacity of switching of 4 STM-1 more 21 VC12, STM-4 ADD/DROP multiplexer with capacity of 63 VC12 over one AU4 per STM-4 card. LAN over VC12 or VC3 interconnection point (via 4E/FE and GFP150 cards) The GFP150 and 4E/FE data traffics are compatible with those of the GFP150 extra card ofthe SURPASS hiT-16.

Number of rows = 9Number of columns= 9+261=270Number of bytes= 9x270Number of bits= 9x270x8Number of bits/ seconds = 9x270x8x8000=155520000=155.520 Mbps (STM-1)Bit rate of STM-N = (Nx155.520) Mbps

INSTALLATION AND COMISSIONING OF STM-1 (SIEMEN)BLOCK DIAGRAM OF TRANSMISSION SYSTEM

ELECTERICAL OPTICAL ELECTERICAL SIGNALSIGNALSIGNAL

TRANSMITTERFDFRECIVERE/O CONVTERE/O CONVTERDDFDDFE/O CONVTERE/O CONVTERFDF

DDF(Digital Distribution Frame) DDF (at transmitter side) receive PCMs from exchange or station which are to be transmitted to another station or exchange. DDF have different modules which connects PCM to STM-1 System. PCM connected to DDF from station through copper cable and from DDF to STM-1 through PCM cable.Transmitter It is basically STM-1 system which helps to transmit PCMs through optical fibre cable.STM-1 plays an important role in transmission system. STM-1 also helps in cross connect the PCMs. This block contains MUX card and OLT cards. E/O Converter It is simply OLT card which converts electrical signal to optical signal FDF(Fibre Distribution frame) This frame (at transmitter end) distribute fibre to different station. FDF connect to system through patch card. FDF(Fibre Distribution frame) This frame (at receiver end) collect fibrefom different station. FDF connect to system through pigtails cable. O/E Converter This block converts optical signal to electrical signal.Receiver This block will collect all PCMs received at OLT card. It will connect all the PCM to MUX card. Here they are connected to different station through DDF.

STM-1 EQUIPMENT (SIEMEN)

Slot- BSlot- AOptional Fan

Slot- DHold over moduleMotherboard Slot- CIt has five slots named as Slot A,Slot B,Slot C,Slot D and Slot M.Slot M is also called as Motherboard.These slots are explained below:

SLOT A :

E1 INPUT" and "E1 OUTPUT" ports 21 x 2 Mbit/s traffic ports compliant with the ITU-T G.703Recommendation ( 6.3 for input port, tab.6 for output port)Bit rate 2,048 Mbit/s 50 ppm,Code HDB3,Impedance 75 or120 balanced, according to the model of motherboardConnector SUB D HD female 44 pins supporting L907 cable (21 ports).This interface uses two connectors : E1 INPUT connector for inputs (named RX) andE1 OUTPUT connector for outputs (named TX)E1 OUTPUT and E1 INPUT G.703 75 or 120 2 Mbit/s traffic ports 120 input is used for transmission and output is for reception.It is also known as U-link connector.This port is used to connect the exchange side and system side.4E/FE:Each 4E/FE provides connection for Traffic Ethernet interface either in 10Mbit//s or 100Mbit/s in full or half duplex mode.

SLOT B :

It is OLT card.OLT stands for Optical Line Termination which converts optical signal into electrical signal and vice-versa.Two fiber cables are connected to this card,one is used for transmission and other is for reception.

IC1.1-2G Card is OLT card . Two optical fibre cables are connected to this card. One cable for transmit the sigal and another one is used for receiving the signalEOW/AUX The EOW/AUX interface provides a 64 kbit/s data channel ; this channel may be carried by a Byte of the SDH frame.

TR" and "REC"ports :Ports 75 ohms 34/45 Mbit/s Interface compliant to ITU-T G.703( 5 and 8) Recommendation and ETS 300 166 allowing 34 Mbit/sor 45Mbit/s plesiochronous stream exclusive connection

SLOT C:

E3DS3 card

E3DS3:

Each E3DS3 provides connection for75 34/45Mbps interface complaint with ITU-T G.703 and ETS 300 166 allowing 34/45 Mbps PDH streams.TR" and "REC"ports :Ports 75 ohms 34/45 Mbit/s Interface compliant to ITU-T G.703( 5 and 8) Recommendation and ETS 300 166 allowing 34 Mbit/sor 45Mbit/s plesiochronous stream exclusive connection

The cards can be extracted without intervening on the other cards or on their connections.SLOT D:

Optical SFPElectrical

STM-1reception portSTM-1 transmission port

STM1-SFP Optical cards

G.957 STM-1 SFP optical ports "TR" and "REC"("TR" transmission port and "REC" reception port)engineering Order Wire port "EOW / AUX"one 64 Kbit/s access "EOW/AUX", order wire channel or auxiliary channel according to the configuration.EOW/AUX The EOW/AUX interface provides a 64 kbit/s data channel ; this channel may be carried by a Byte of the SDH frame.

TR" and "REC"ports :Ports 75 ohms 34/45 Mbit/s Interface compliant to ITU-T G.703( 5 and 8) Recommendation and ETS 300 166 allowing 34 Mbit/sor 45Mbit/s plesiochronous stream exclusive connection

The connections to be performed on the equipment depend on the chosen configuration :

On the subrack motherboard strip : power supply ports : " POWER 48V 2A MAXI "Remote indication, remote control and station alarm port "LOOPS"IP address configuration port "COMM" : allows the connection to a VT 100 emulation orhyperterminalEthernet management port "ETH".2 Mbit/s / 2MHz G.703 120 synchronization port "SYNC"21x2Mbit/s G.703 75 or 120 traffic ports "E1 INPUT and E1 OUTPUT".

MOTHERBOARD SLOT(SLOT M):

COMM PORT :This is RS232 Port which is used to connect system to computer standard. It is used for upgradation.

ETH PORT : This is commonly called as Ethernet port . It is used for networkmanagement purpose (NMS). It is used in STM 1 configuration.

SYNC PORT: It is called as synchronization port and clocks are provided with the help of this port.

120E1 Input/Output: E1 INPUT" and "E1 OUTPUT" ports 21 x 2 Mbit/s traffic ports compliant with the ITU-T G.703Recommendation ( 6.3 for input port, tab.6 for output port)Bit rate 2,048 Mbit/s 50 ppm,Code HDB3,Impedance 75 or120 balanced, according to the model of motherboardConnector SUB D HD female 44 pins supporting L907 cable (21 ports).This interface uses two connectors : E1 INPUT connector for inputs (named RX) andE1 OUTPUT connector for outputs (named TX)E1 OUTPUT and E1 INPUT G.703 75 or 120 2 Mbit/s traffic ports 120 input is used for transmission and output is for reception.It is also known as U-link connector.This port is used to connect the exchange side and system side.ACK PORT:It is for Acknowledgment.ALM: M: Major alarm is ON when route fails.m: minor alarm goes ON when any PCM fails.

LOOPS:Loops and remote signalling

POWER 48V/2A MAXI Power supply

STM1-DUAL card : STM-4 transmission portSTM-4 reception portConnecting STM1-DUAL Optical cards

G.957 STM-1 SFP optical ports "TR" and "REC" one STM1 SFP optical interface ("TR" transmission port and "REC" reception port) G.703 STM-1 electrical ports "TR" and "REC" one STM1 electrical interface ("TR" transmission port and "REC" reception port). engineering Order Wire ports "EOW / AUXone 64 Kbit/s access "EOW/AUX", order wire channel or auxiliary channel according to the configuration.

Connecting on 21E120, 21E75, 21E1R8 cards2Mbit/s transmission port2Mbit/s reception port

Connecting 21E120, 21E75, 21E1R8 cards

2 Mbit/s traffic connections (75 or 120 according to the card), performed on "E1 INPUT" and"E1 OUTPUT" ports on the 21E120, 21E75, 21E1R8 card are identical with those performed on"E1 INPUT" and "E1 OUTPUT" ports on the front side of the motherboard (see 1.3.1.5)Note : on the 21E1R8, the retiming function is supported by the ports #1 to #8

TOPOLOGY USED IN STM-1

STM-1 can work with following topologies:1.Star topology2.Ring topology3.Bus topologyBut,Ring topology is used in this and is explained below:

RAJPURA135.10.110.13

AMBALA135.10.110.15

PATIALA135.10.110.11

RING TOPOLOGY

CONFIGURATION

IP AddressesTo operate the STM -1 Equipment with NMS, we must set the IP address of NMS. First three bytes of IP address of NMS must be same as that of STM-1 Equipment.How to change the IP address : My Network Places Properties Local Area Network Propertie IP Address Properties Give IP address 135: 10: 110: 100 CROSS-CONNECTIONCross Connection is important function of STM-1 Equipment. By using this function we can connect PCMs of one station toPCMs of another station. Shelf View---Cross-Connection---Select Output Port---Configure---Select Input Port---Apply

We can also give the protection path, if working path has been failed.Goto Configure---Protection---Protection Input Port---Apply

Another important function in cross connection is Multiple connections. By using this function we can connect more than 1 PCM to another stations PCM. For established multiple connections we must following.

Now multiple connections are established. We can also give them protective pathby using protection function of cross connection.

Each cross-connection is defined by its parametersOutput port Connection Destination End (Slot name and port number of selected card)Mode Unidirectional or Bi-directional

4E/FE CARDThe SDH bandwidth can be divided among separate connections to match fine requirements with great flexibility and with optimal usage of the STM1 link.The 4E/FE can terminate a combination of VC3 and VC12 connections up to an aggregated bandwidth of 1 STM1. Multiple VC3 or VC12 connections are grouped together in a VC Group (VCG) with Virtual Concatenation. The VC members of a given VCG do not need to be contiguous. They do not need to take the same path across the SDH core network either. The bandwidth of a VCG VC3-nV is n times the bandwidth of 1 VC3. The bandwidth of a VCG VC12-nV is n times the bandwidth of 1 VC12.

An EPLine service (Ethernet Private Line) allowing Ethernet 10/100 BaseT point to point interconnectionthrough a SDH network by using, for each connection, a VCG (VC-Group) based on virtual concatenation(VCAT). Its possible to obtain up to 4 independant point to point connections per 4E/FE card. Rategranularity for each VCG is based either on VC12, or on VC3. With each VCG, its possible to concatenatefrom 1 to 46 VC12 or from 1 to 2 VC3. The sum of the concatenated Ethernet rates, on the whole of the 4ETH ports, cant be above the STM1 payload (about 150Mbit/s).

Click on the VCG block, then on the List link. For the selected VCG#1 interface, click on VC#1 and then onthe Multiple Add Member link. In the new screen coming up, select VC12 as type and VC#6 as lastconnection. Click on Apply in order to create the virtually concatenated group of 6 VC12 (VC12#1 to VC12#6)that will be used to transport Ethernet traffic.

Click on the XCN block. Configure the connections from VC12#1 to VC12#6 of the 4E/FE card in way where 3VC12 go through a SDH card and the 3 other VC12 go through a second SDH card. Make sure you have endto-end SDH connectivity with the remote SURPASS hiT -1/4E.