Telephony Trainers with Discovery Software



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Teephony Trainers 58 Series Teephony Trainers with Discovery Software 58-001 Teephony Training System 58-002 Digita Switching System 58-003 Digita Teephony Training System 58-004 Digita Trunk Network System 1

Teephony Training Systems P C computer contro 58-001 TELEPHONY TRAINING SYSTEM 92-200 RAT 58-100 Teephone & Interface 58-110 TDM/PCM Principes P C computer contro 58-002 DIGITAL SWITCHING SYSTEM 58-121 Controer 58-122 Digita Switching 58-123 Teephone Tray IBM P CPC computer or compatibe contro 58-003 DIGITAL TELEPHONY TRAINING SYSTEM 58-121 Controer 58-122 Digita Switching 58-122 Digita Switching 58-123 Teephone Tray 58-123 Teephone Tray 58-140 Trunk Networks The addition of 58-140 board to the 58-003 System converts it into a 58-004 Digita Trunk Network System 2

Features Covers teephony principes and modern practice Uses commercia teephony components Provides access to a signas Uses Discovery software Automatic practica configuration - no patching Description Teephones and teephony are an essentia part of modern iving and teecommunications is one of the word s fastest growing industries. The demand for technicians and engineers with knowedge of the principes of this area of technoogy wi increase with this growth. This range of Teephony Trainers with Discovery software is a modern, PC-based, computer controed training system that has been designed to introduce and demonstrate the principes of modern teephone systems. The Trainers are a combination of hardware workboards and Discovery software, which together provide a totay integrated deivery system for teaching a wide spectrum of teephony concepts and appications, from the characteristics of individua components to the use of compex systems. 3

Compete Systems Each Teephony Workstation consists of: Workstation computer Interface system Rea-time Access Termina (RAT) or Controer One or more Teephony workboards Discovery Software Interface System Discovery Software The Teephony Training System incudes a USB Rea-time Access Termina (RAT) for interface to the PC. The Digita Switching System incudes a Controer unit to provide a the specia power suppies and PC interface circuitry. In combination with the hardware, Discovery Software is suppied with the system. This forms an innovative and motivating deivery system which enabes a wide range of tuition to be carried out. Background theory, board configuration, practica contro, instructions and questions, together with PC-based instrumentation is a integrated into the Discovery environment, suppying a the instruction and measurement requirements for the experiments. The test points used by the PC-based instrumentation in the experiments are dupicated on the workboard, aowing standard Test instruments to be connected if required. Discovery software is a browser-based deivery system enabing instructiona, integrated hardware contro. It aows totay free movement between software screens and has a user-friendy graphica interface. A text is editabe. The computer configuration of the workboards avaiabe with Discovery software eiminates practica set-up time, ensuring that the correct connections are automaticay made. This significanty increases the time avaiabe for actua practica work and the efficiency of aboratory sessions. 4

Curricuum In addition to the integra Discovery software, each Workstation is supported by manuas provided on a CD ROM (together with the Discovery software) a Student Workbook and an Instaation Manua. The Student Workbook has been designed to be used aongside the on-screen Discovery software. For each assignment, the Learning Outcomes and Competencies are isted and students demonstrate their achievement of competence by satisfactoriy competing the Workbook. This invoves such activities as suppying missing keywords, competing bock diagrams, making measurements, sketching waveforms, etc. The Workbook has sections for answering the on-screen Discovery questions. In addition, the Workbook is a vauabe revision aid for students, as the key points of the theoretica and background work to assignments are aso incuded. The Instaation Manua detais the hardware and software instaation and operation, the editing faciity, circuit diagrams, etc. It aso contains typica answers to the student activities and questions. 5

Teephony Training System 58-001 Description The system comprises two boards: Teephone and Interface TDM/PCM Principes a RAT (Rea-time Access Termina) and Discovery Software The Teephony Training System is a stand-aone trainer designed to enabe students to study the principes of teephony and gain experience into modern teephony practice. It is a compete package deaing with teephone system theory and practice and combines industry hardware with specia circuits designed to demonstrate the underying principes. The instruction is essentiay non-mathematica and is particuary suited to vocationa and technician eve courses, or for the introductory principes required for further study in teephony systems in undergraduate courses. 6

The Teephony Training System 58-001 contains two workboards and covers a wide range of assignment work. Curricuum Teephone and Interface Workboard Teephone Signaing Switch Hook Keypad Ringing (Aerting) Teephone Speech Receiver Transmitter (Microphone) Teephone hybrid circuit Subscriber s Line Interface Circuit (SLIC) Battery Feed Overvotage protection Ringing (Aerting) Signaing Dua Tone Muti Frequency (DTMF) signaing DTMF Codes Frequency Measurement Tone Duration Speech Immunity SLIC Hybrid Forward oss Return baance oss Testing Test-Out Test-In TDM/PCM Principes Workboard Samping Samping Introduction Aiassing error Interference Mutipexing (TDM) Mutipexing Introduction Time sots and Frames Puse Code Moduation (PCM) Quantisation Quantisation noise Interference Companding Linear Conversion Companding characteristic Companding appication Fitering Aiassing error Fitered conversion Mutichanne PCM 24 and 30 Channe Systems Frame Synchronisation Contro 7

Teephone and Interface The Teephone and Interface is an open format board which uses a commercia singe-piece teephone to examine the signaing and speech circuits and the immediate interface at the exchange. The board contains an acoustic couper to enabe a tone signa to be appied to the teephone transmitter. The operation of the teephone handset, the acoustic couper and the circuitry associated with the Subscriber s Line Interface Circuit (SLIC) is investigated, showing the structure of the teephone with speech and signaing circuits and their operation in conjunction with the SLIC. The three signaing circuits of the teephone are examined, as are the three speech circuits. The functions of the first interface circuit are examined. In a commercia system they woud be contained in a Subscriber s Line Interface Circuit (SLIC). Five of the functions of the BORSCHT acronym are covered. The characteristics of dua tone mutifrequency (DTMF) signaing as used for the contro of teephone cas are determined. The use of a high quaity, commercia hybrid in the SLIC enabes usefu measurements to be made. TDM/PCM Principes This board aows the study of the underying principes of time division mutipexing (TDM) and puse code moduation (PCM). It is based on the use of standard teephony devices but aso uses specia circuits to enabe the effects of variabe samping rate, bit rate and fitering to be demonstrated. Puse Ampitude Moduation (PAM) is used to demonstrate the concept of taking short sampes to represent a continuous waveform. Time Division Mutipexing is demonstrated by muti-channe Puse Ampitude Moduation (PAM) which visuay shows the principe of sharing a singe physica ink between different communication channes. Constant vaues and audio sampes are converted into digita form. The effects of quantisation are studied. Linear A/D conversion is compared with compression and expansion using a standard codec. The use of band-pass fiters to avoid aiassing error is demonstrated. The standard 30 channe PCM system is introduced and requirements for synchronisation and contro are discussed. Comparison between 24 and 30 channe systems can be made. 8

Digita Switching System 58-002 Description The Digita Switching System is an easy to use trainer for the investigation of digita teephone switching circuits and their appications. With this system a student may study the principes of digita switching in teephony and aso gain experience into modern teephony practice. The modues use both current standard teephony devices as we as specia circuits designed to deveop an understanding of the methods empoyed. The system aows the performance of a wide range of experiments within the subject area to be investigated. Assignments incude genera introductory materia and each practica is supported by background information and tutoria questions, in the standard Feedback Discovery format. The System comprises a digita switching centre, a controer, four teephones and Discovery software. It is compementary to the Feedback Teephony Training System, 58-001. Protection is provided on a units to ensure there are no dangerous votages accessibe by the students. 9

The assignments cover: Loca signaing Operation Tones and cadences Digita Switch Principes Time switching Time & space switching Digita switch contro Contro of time switch Connection of tones Line scan Switch hook DTMF receivers Ca records Ca state Line identities Ca time Line records Directory numbers Ca accounting Line maps Location maps Condition maps State transitions Inputs Outputs Tasks Ca progress Ca set up Ca suspension Ca reease Manua contro Contro Curricuum Coverage This system progresses from the hardware aspects of digita switching, incuding time and space switching and the contro of a digita switch by a connection memory, to the software aspects of digita teephone switching and contro. Emphasis is paced on the Ca State Transition Diagram, conforming to the CCITT SDL format, for contro of ca progress. The concepts of ca state and state transition are demonstrated in detai. The three stages of ca handing, set-up, supervision and cear down are demonstrated and may be manuay controed by the student. Traffic statistics, testing and programming of the signa tones are investigated. Controer The Controer contains the microprocessor-based circuitry for contro and the specia power suppies required by the teephones and their associated circuits. It interfaces with the PC through a card suppied with the system, with controing code downoaded from the PC on switch-on. This makes for uncompicated upgrading via the Discovery software. Up to three exchanges may be run from one controer. Digita Switching Centre The Digita Switching Centre is an open-board format unit containing four compete teephone ine circuits and a the digita switching and signaing associated with a modern digita teephone system. Two connections to other digita switching centres (trunk interfaces), four teephones and a convenient tray for housing them are aso provided. A system containing two switching centres may be set-up using an additiona, optiona Digita Switching Centre board. Computer Connection The system is suppied with software and hardware to interface to a PC. Power Suppy A power suppies required by the system are provided with the trainer. Testing Test out and oop back Traffic System traffic 10

Digita.Teephony.Training.System 58-003 The additiona curricuum incudes assignments on the foowing topics: Trunk Configuration Trunk paths Numbering Tones and cadences Trunk Switching Outward path Return path Signa Protoco Controer Fags Frame check sequence Zero insertion (bit stuffing) Trunk Signa Units Message signa units Fi-in signa units Description This training system covers a of the work that can be performed with the Digita Switching System 58-002 and extends it to incude trunk switching and message handing. The System has an additiona Digita Switching Centre and its four associated teephones and incudes eight extra assignments to extend the curricuum to trunk traffic topics. The work that can be carried out with this Trainer progresses from the investigation of oca and interswitching centre numbers and their origination, through trunk switching, highways and timesots, to ca state transition diagrams and ca records for a two switching centre system. CCITT (now ITUT) codes and formats are used. The Trainer is computer-controed and uses Discovery software: an integrated instructiona and hardware contro program which incudes ogic anaysis and dispay of resuts. The instruction is essentiay non-mathematica and is particuary suited to vocationa and technician eve courses, or for the introductory principes required for further study of teephony systems in undergraduate courses. Signaing Information Fied Labe Heading codes Address signas Error Contro Sequence numbers Buffers Trunk State Diagrams Originating switch Diaing Destination switch Trunk Ca Progress Originating switch Diaing Destination switch 11

Digita.Trunk Network System 58-004 The additiona curricuum incudes assignments on the foowing topics: Transit Switching Centre Numbering Transit Switch CSTD Transit Signaing Transit Switching Ca Progress Transit Switch Centre Originating Switch Destination Switch Two Leve Transit Switching Numbering Diaing CSTD Routeing Tabes Description The system comprises: Controer 2 Digita Switching Centre Boards 2 Four Teephone Handset Kits Trunk Networks Board In addition to the curricuum covered by 58-002 and 58-003 the Trunks Network Board has three transit switches and extends the work to cover transit switching and signaing. Two Leve Transit Ca Progress Signaing 1st & 2nd Leve Switches Non-associated Signaing Signaing Ca Progress System Testing TCAP Signaing Testing Manua Testing The system can be configured as four oca switching centres, to cover simpe transit switching, two eve transit switching, non-associated signaing and the use of ITU-T type transaction capabiity messages to contro system testing. For ease of use and to accommodate a the modues on the student bench a vertica mounting-rack is avaiabe as an optiona extra. A systems require the use of a standard PC. 12

Tender Specifications TIMSWIT Timeswitching Teephony Training System 58-001 Digita Switching System 58-002 MATSWIT Staged Group Switching Digita Teephony Training System 58-003 TELTRAF Teephony Traffic Digita Trunk Network System 58-004 TIMSWIT is a computer simuation of the process of switching seria digita data transmissions within PCM teephone or ISDN digita networks. It provides interactive demonstrations and A sef-contained, open-board based, Teephony trainer using exercises for student instruction. Assignments on a aspects software contro and computer-assisted instruction. The system of the programme compete a comprehensive package. shoud TIMSWIT contain A introduces a 100Msampe/s the concepts Rapid Access used in Termina synchronous with USB interface transmission (to connect and the to conventions a PC with a used Windows the operating computer system); Teephone simuation. and Interface workboard; TDM/PCM Principes workboard TIMSWIT and B shows accompanying the operation software. a time The switch system which shoud operate changes with the computer sequence aided of data aboratory in one data software highway, which incudes provides on-screen an exercise instruction, controing contro the and switch instrumentation and aso shows for tweve how computer-based synchronisation assignments and signaing are functions provided can with be the provided system. in the same seria transmission. TIMSWIT C extends the scope to combine time and space switching. Again an exercise in controing this more compex structure is provided. A sef-contained, open-board based, Digita Switching Teephony trainer using software contro and computer-assisted instruction. The MATSWIT system shoud is a computer contain simuation a Controer of with a three-stage power outputs matrix and microprocessor-based switch which provides circuitry economy for of contro; switches USB at interface the risk of (to connect interna to bocking. a PC with Interactive a Windows demonstrations, operating system); test routines a Digita Switching with storage Centre for the workboard; resuts and four tutoria teephones materia with teephone a aspects tray and of the accompanying programme software. make up a The comprehensive system shoud package. operate with computer MATSWIT aided A uses aboratory a graphica software dispay which to provides demonstrate on-screen how the switch operates and how bocking may occur even if instruction, contro and instrumentation for tweve computerbased there are sti free switches and connections. MATSWIT assignments B provides are fast to be operation provided of with the the simuation system. so that statistica profies of the matrix operation with different contro agorithms can be obtained. MATSWIT C simuates continuous use of the matrix at chosen A traffic sef-contained, eves to provide open-board aternative based, comparisons Digita Teephony between trainer the using agorithms. software contro and computer-assisted instruction. The system shoud contain a Controer with power outputs and microprocessor-based circuitry for contro; USB interface (to connect TELTRAF to a is PC a with computer a Windows simuation operating of a concentration system); a Digita switch Switching in a teephone Centre switching workboard; system. four teephones Its operation with provides teephone an tray introduction to the basic concepts of traffic theory, giving and accompanying software. The system shoud operate with students practica experience of fuctuating data which has to computer aided aboratory software which provides on-screen be described in statistica terms. instruction, TELTRAF contro A modes and a instrumentation concentration switch for twenty-four with 24 inets, computerbased 10 outets. assignments. Traffic fow and mean hod time are under the users 1 to contro. The connections are seected at random, so that a simuations are unique. The simuation can be operated in singe steps, or aowed to run continuousy, with or without the A dispay. sef-contained, Hence users open-board can expore based, the Digita simuation Trunk Networks in their own trainer way, at using their software own speed. contro At any and time computer-assisted the history graph instruction. can be The seen system which shoud shows contain the recent a Controer sequence with of power connections outputs against and microprocessor-based time. Assignments cover circuitry basic for traffic contro; theory USB and interface traffic oss. (to TELTRAF B covers arger switches, up to 1000 inets and 50 connect to a PC with a Windows operating system); two Digita outets, giving a much wider range of possibe simuations. Switching Centre workboards; eight teephones on teephone The distribution of occupation of the outets can be dispayed, trays and and stored accompanying with the resuts. software. Assignments The system are provided shoud operate on with outets computer (trunk) aided requirements aboratory and software cas wait which (deay) provides systems. onscreen instruction, contro and instrumentation for thirty computer-based assignments. 13

TRAFCALC Traffic Cacuations DATNOD Packet Transmission TRAFCALC is a utiity program for cacuation of the standard distributions used for teephone traffic. Five traffic modes are provided; ERLANG B (cas ost), ERLANG C (cas wait), ENGSET (finite number of sources), BINOMIAL or BERNOULLI (not more sources than servers) and POISSON incuding MOLINA expression for cas waiting. The compete traffic distribution is avaiabe and can be stored with the resuts if required. This page intentionay eft bank DATNOD simuates the transmission of data as packets or as a message through the nodes of a wide area computer network. Simuation features are introduced intwo stages. The genera objective of DATNOD is to find the time for transmission of a given set of data, and the effect of many different parameters on the time taken. In DATNOD A ony one node is used, but many other aspects of data transmission can be studied. Assignments are provided to determine the transmission time with different packet sizes and with message switching, or different amounts of data, over different distances and with different transmission rates. In DATNOD B additiona nodes can be introduced, and deay at each node and a sateite ink are possibe. Further assign ments on transmission time are given. Finay, an extended assignment is provided which uses DATNOD to pan packet transmission in a computer network. DATQ Packet Switching Queues DATQ simuates the formation of queues at a node of a packet switching network. The node has up to four inet buffers, from which packets are transferred to a queue, where they wait to be transmitted from an Outet Buffer. The features of the mode are graduay introduced in three stages. In DATQ A the M/M/1 queue is introduced. Assignments are provided on statistica fuctuations of the queue parameters, on the variation of queue ength and time deay with usage of the node, and on the oss of packets if the queue is not sufficient. In DATQ B other queue discipines can be observed. These incude the M/G/1 and M/D/1 types. Queue behaviour with fewer inets can aso be seen. Further assignments are possibe on queue ength, time deay and packet oss in a wider range of situations. In DATQ C a aspects of the node are under the contro of the user, incuding transmission rates for the inets and outets, and a queue type which can be defined by the user, aowing a wide range of nodes to be modeed. DATQ is aso suitabe for students concerned with queueing theory in other discipines. 14

This page intentionay eft bank 15

Teephony Trainer Product Numbers Listed beow are the product numbers of the constituent parts of the two Teephony Trainer Workstations. Each of the workstations may be ordered as a compete system, using the composite order numbers given at the start of the reevant section. However, shoud you wish to cover ony part of the described curricuum you may not need a of the modues in the workstation. In such cases you may order just the modues that you do require. Pease contact either your oca agent, or Feedback, if you require more information. Teephony Training System 58-001 composite equipment: Rapid Access Termina (RAT) 92-200 Teephone and Interface 58-100 TDM/PCM Principes 58-110 Teephony Trainer Discovery Software 58-912 Digita Teephony Training System 58-003 composite equipment: Controer 58-121 Digita Switching Centre x2 58-122 Teephone Tray x2 58-123 Digita Switching System Discovery Software 58-914 Digita Switching System 58-002 composite equipment: Controer 58-121 Digita Switching Centre 58-122 Teephone Tray 58-123 Digita Switching System Discovery Software 58-914 Digita Trunk Network System 58-004 composite equipment: Controer 58-121 Digita Switching Centre x2 58-122 Teephone Tray x2 58-123 Trunk Network Board 58-140 Digita Switching System Discovery Software 58-914 Ordering Information To order any of the Teephony Systems simpy quote the tite and number of the workstation as given at the start of each section. 16