Wavetek Wandel Goltermann: The New Logo GSM Network Optimization · PDF fileSDH Network? Path trace analysis becomes increasingly critical when multiple providers are involved in signal

Wavetek Wandel Goltermann:The New Logo

GSM Network Optimization

SDH/SONETand DVBMeasurements

OTDR Standards

COMPANY NEWS

3 Wavetek Wandel Goltermann:The New Logo

6 Wavetek Wandel Goltermannin the Trade Press

11 Flying Hirewith Microlease

FOCUS

4 GSM Network Optimization:New Software Package for MA-10A

6 MA-10A Now SupportsGPRS and CAMEL

PRODUCT NEWS

7 How Do You Test OC-48c?A New Option for the ANT-20

11 OLP-8 Optical Power Meter:Optimized for CATV applications

15 New High Performance OTDR Modules FacilitateFiber Optic Cable Monitoring over 200 km Radius

18 LANchecker 100:Active Testing of Ethernet and Fast Ethernet

19 Introducing DominoPLUS:Single Chassis Supports Many Network Interfaces

20 IUM-10: The Ideal Solution for DetectingTransmission Problems on In-Service ISDN Lines

21 WG IBT-5: ISDN Basic Rate Tester DeliversReal-Time Tracing and Printing of Results.WG IBT-5/-10/-20: Q.SIG and CorNET Protocols

22 WG DA-5: First Protocol Analyzer on the Marketto Support AO/DI

26 WG QMS: Making Service Level AgreementsManageable

APPLICATIONS

8 PHOTON Field Trial: Experiences in CombiningOptical Measuring Techniques with SDH Analysis

16 Requirements for Reliable Broadband Services:Noise Interference Measurements on xDSL Circuits

23 Broadcasters are Committed to QoS with theDTS-400P Digital Broadcast Monitoring System

24 Digital Broadcast:Set-Top Boxes Customization

BACKGROUND

12 OTDR Standards Move Towards Reflectingthe User's Real Needs

CONTENTS

Publishing informationªbitsº is the customer magazine of theWavetek Wandel Goltermann Groupand is published 3-4 times a year.Issue 84: June 1999Published by Wandel Goltermann GmbH & Co,Elektronische Meûtechnik,PO Box 1262, 72795 Eningen u.A., GermanyEditor-in-chief: Burkhard Braach,Tel. +49 7121 86 1793, Fax +49 7121 86 1333Coordination: Bernd Schepper,Tel. +49 7121 86 1287, Fax +49 7121 86 1333The Editor will be pleased to grant permissionto reproduce parts of this publication on request.Source acknowledgment is required.Printed in Germany

Subscribe now at www.wg.com!

2 W a v e t e k W a n d e l G o l t e r m a n n b i t s 8 4

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bits 8464

Test equipment in digital networks

Basic principles and measurement techniquesfor PDH, SDH, ISDN and ATM

How do you go about testing the quality of2 Mbit/s leased lines? How does SDH work? Howdo you check an ATM traffic contract? When arejitter measurements important? How do youtroubleshoot ISDN systems? How do you goabout selecting test equipment?Answers to these questions and many more canby found in the book ªTest solutions for digitalnetworksº by author Roland Kiefer.The book is about 270 pageslong and is published by HuÈ thigVerlag, Heidelberg (Germany).It is available in English (ISBN3-7785-2699-5) and German(ISBN 3-7785-2527-1).To obtain a copy, contactyour local book dealer or anyWWG sales company.

New Application Notes

Optimizing Mobile Radio Radio Networks

Improving quality of service and optimizingnetwork utilization are the topicsof Application Note 61.

ITU-T Recommendations on Error Performance

Application Note 62 provides an overviewof Recommendations G.826, G.821,the M.21xx series and their practicalapplications.

How Reliable is the Routing in YourSDH Network?

Path trace analysis becomes increasingly criticalwhen multiple providers are involved in signaltransport. Application Note 64describes how to test under theseconditions.

See back page for more company literature!

W a v e t e k W a n d e l G o l t e r m a n n b i t s 8 4

Wavetek Wandel Goltermann is committed to providinga complete portfolio of high-quality, reliable testsolutions to help our customers worldwide gain acompetitive edge. We are constantly evolving to meetever-changing test requirements. In the process, theCompany is reinventing itself as it works to maximizethe synergies of its merger last year.

Our new logo symbolizes progression into the nextcentury. It represents our focus on research anddevelopment to catch the waves of emergingcommunications technologies to provide the mostappropriate test solutions.The ªarmsº of our logo curve to form the ªcº incommunications. Wavetek Wandel Goltermann is theleading company worldwide devoted entirely tocommunications test. These arms represent our manyproduct lines creating a complete range of test productsor our manufacturing divisions or worldwide sales andservice companies. The arrow point of the logo visuallyrepresents our positive, focused approach of servingcustomer needs according to their uniquegeographical and cultural expectations. Whenever yousee our new logo, you can be sure that our tradition ofquality and service stands behind it.Wavetek Wandel Goltermann is also changingorganizationally to better serve you, the customer. It hascombined product competencies across locations toform strong, focused business lines. Expanded productranges and improved service have resulted. Practicallyspeaking, this means the fiber optic business line nowranks number three globally in this Field Test segment.It is now a core business for the Company. Design andmanufacturing of test solutions in Wireless, EnterpriseNetworks and Switching have also been united to moreaccurately reflect our customers testing requirements.This complements our strong performance in LocalLoop, Transmission and CATV Test. It also means thatwe are prepared to partner with our customers for alltheir specialized testing needs.To enhance sales and services globally, some salesoffices have been combined while new offices haveopened. New offices are now operating in Taiwan andPoland.Check the Company's web site at www.wg.comto locate the sales office nearest to youor call in Germany at +49-7121-86-1816.Wavetek Wandel Goltermann is proud of its combined113-year history, proud of its roots that reach back tothe beginning of communications test. Nevertheless, weare excited about our future and the potential for growthand innovation in the new millennium. Our new logo andthe operational changes behind it embody both: thestrength and stability of our heritage and the new vistasand opportunities that lie ahead.

COMPANY NEWS

QMonitor V3.2 now runs underWindows NT too

Version V3.2 of our QMonitor TMN/Q3 analysissoftware can now be used under Windows 95and Windows NT. QMonitor decodes the Q3protocols and analyzes management information.A conformance test checks whether data behaveaccording to the application-specific informationmodel. Graphical evaluations provide visualinsight into complex relationships. Managedobjects can be fully decoded according tothe information model. For details, seewww.qmonitor.wg.com.

Easy operation simplifiesGSM service

Service of all types of GSM phones includingcrossband and data function testing is nowsimpler with the Wavetek 4200S. Workshops canincrease repair capability, improve customersupport and reduce turnaround times. Automatedmeasurements are provided for all relevant GSMparameters and specifications. Tests and limitscan be modified for different user needs ordifferent phones.

WWG and NetScout Systemssign multi-year, worldwidedistribution agreement

In March 1999, Wavetek Wandel Goltermannannounced a strategic OEM and resellerpartnership with NetScout* Systems, Inc.,a leader in end-to-end Application FlowManagement for the enterprise network. Themulti-year OEM agreement extends the alliancewhich began three years ago with the goal ofstrengthening international sales efforts to meetincreasing demand for NetScout's industry-leading application-flow network monitoringsolutions.Wavetek Wandel Goltermann, with more than80 sales offices worldwide, continues tosuccessfully deploy these solutions into bothenterprise and carrier networks.The recently executed agreements also allowNetScout Systems to resell Wavetek WandelGoltermann's ExamineTM decode engine andMentorTM expert analysis product on an OEMbasis.Further information on NetScout Systems isavailable on the World Wide Web atwww.netscout.com.

3

FOCUS

When the MA-10 Mobile Radio andSS7 Analyzer first started to be used bysystems manufacturers and network providerssome five years ago, the main task wasdecoding the signaling information. Today,the emphasis has shifted: Overall qualityof service is now a key factor in globalcompetition. This new situation is reflected inthe latest optimization software for the MA-10from Wavetek Wandel Goltermann.

GSM Network Optimization:

New Software Package for MA-10A

The new GSM Network Optimization Softwaregraphically evaluates network behavior using theinformation at the A and Abis interfaces.It is thus a useful complement to the existingUtility Network Optimization (UNO) and NetworkOptimization Solutions (NOS) optimization tools.The source files for optimization are generatedby the MA-10A Mobile Radio Analyzer using theMONITOR Abis and MONITOR MSC signalinganalysis software. These files are then importedby the GSM optimization program for off-lineanalysis with any PC, the MA-10A hardware notbeing required for this.Voice quality is the main criterion by whichmobile users judge the network, since it is thefirst thing noticed when using the telephone.As a result, network providers are interested inassessing and optimizing the objectiveparameters for this subjective factor. Thisincludes avoiding interference and multipathpropagation.

The new software completely assesses a BTS(base transceiver station) with up to tentransceivers by simultaneous evaluation of Abisinterface information. Conclusions regarding twotypes of problem can be drawn from the graphicaldisplay (figure below left):

± Network coverage problems ± most pointstested show low receive levels and poorreception quality.

± Interference problems / long signal delays ±reception quality is poor despite a high receivelevel.

These and other types of analysis are generatedautomatically by the GSM optimization software.If a fault is detected in a BTS, coverage can bedetermined by filtering to a single transceiver orto the TEIs (terminal endpoint identifiers).The new software also captures information onthe A interface between the BSC (base stationcontroller) and MSC (mobile switching center).

All BSSMAP (base station management applicationpart), DTAP (direct transfer application part), SCCP(signaling connection control part) and handovermessages are extracted from data saved by theMONITOR MSC function and displayed graphically.The following pre-defined analyses are performedautomatically:

. Handover failure analysis

. Handover cause analysis

. Clear request analysis

. Assignment failure analysis

. Disconnect analysis

. Connection success analysis

. Connection request analysis

The statistics tools cover all messages atthe A and Abis interfaces. The results can befurther processed manually or automatically.


Poor quality at low field strengthindicates lack of coverage

Poor quality at high field strengthindicates interferenceor excessive delay

Ideal condition:No interference

Graphic display ofmeasured receptionquality (0 = good,7 = poor) versusreceive level. Eachred dot represents ameasurement result.The display allowsassessment ofnetwork coverageand interference.

Simultaneousrecording of Abis andA interface informationallows completeinvestigations of e.g.handover problems.

BSC

BTS

BTS

BTS

BTS

Abis

A MSC

MONITORAbis

MONITORMSC

GSM NetworkOptimization

Software

Advantages of GSM network optimizationvia fixed network interfaces

The message reports sent to the BTS by everymobile phone around twice a second providemost of the information needed about thenetwork. Evaluation at fixed network interfacesthus has distinct advantages over measurementsmade in an operation & maintenance center(OMC):

. No additional network load generated bymeasurements.

. Problems can be detected more precisely bycontinuous long-term monitoring.

. The MA-10A software can detect inherentsystem faults that may not be found by an OMCif it is provided by the same supplier as the restof the network equipment (BTS, BSC).

. The MA-10A allows specific call tracing andhandover analysis.

The fixed network interface measurement alsohas advantages over on-site measurements suchas drive tests:

. The measurement reports at the Abis interfaceinclude results for both up-link and down-link.

. Wider ranging correlation between majorparameters can be detected.

. Island problems (and splash coverage) can bedetected systematically rather than by accidentwith on-site field strength measurements.

. The causes of handover errors can be seendirectly by monitoring the fixed networkinterfaces; they cannot be determined by on-siteradio field strength measurements.

. Powerful software tools can capture andevaluate information faster and more efficientlyat fixed network interfaces than on-site staff.

Marc KahabkaWavetek Wandel GoltermannEningen, Germany

FOCUS

W a v e t e k W a n d e l G o l t e r m a n n b i t s 8 4 5

Separate handovererror analysis foreach different type ofhandover

What are the causesof dropped calls?

Which types ofconnection wereused during the periodmonitored?

Order GSM NetworkOptimization Softwaredata sheets free ofcharge.

Application Note 61`̀ Optimizing MobileRadio Networks withthe MA-10Aº is alsoavailable.

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COMPANY NEWS

6

MA-10A Now Supports

GPRS and CAMEL

With the new version of MONITOR MSC (V4.0),the MA-10A Mobile Radio and SS7 Analyzer cannow decode the protocols of the Gb interface inthe GPRS network. GPRS technology (generalpacket radio service) enables data transmissionvia GSM at up to 144 kbit/s using packet-orientedtransmission.Decoding of the CAMEL protocol is also partof the new MONITOR MSC. CAMEL (customizedapplication of mobile enhanced logic) controlsmany intelligent network functions within GSM.Both extensions are available as an option.

BSC

BTS

BTS

BTS

BTS

Abis

A MSC

GSN GSN

GSNNetwork ofanother operator

Public network withpacket switching

MA-10A

GPRSregister

Gb

NEW!

Gr

Gs Gp

Gn Gi

GPRS: General packet radio serviceGSN: GPRS support node

DataSignaling

Um

Wavetek Wandel Goltermann

in the Trade Press

In February,test ± The EuropeanTest Industry Journal ±published the articleªDense approachexpands opticallyº.Here, authors fromWavetek WandelGoltermann explainwhy we need densewavelength divisionmultiplexing ± andthe technology'sbenefits. For moreabout the magazine,see www.insid-electronics.com.

ªWandel & Goltermannand Wavetek. A newdimension in the worldof test equipment forcommunicationsnetworks.º This ishow the text on thefront cover fromNovember's issue ofthe Revista EspanÄ olade ElectroÂ nicatranslates. WWG alsohas articles in theMarch and May issues.The Web site of thismagazine popular inSpain and LatinAmerica can be foundat www.redeweb.com.

WG's DominoGigabittook honors for itsªexcellent decodesand solidly built data-capturing pods thatprovides insight intoboth high-level andlow-level protocolanalyzers,º wroteNetwork Computingin its February 8, 1999issue.Network Computinghas online news atwww.networkcomput-ing.com. An offprint ofthe article ªWandel &Goltermann's High-Speed ProtocolAnalyzers Tops in Testºis available from WWG.

Issue 5/99 of theGerman-languagemagazine gateway(March 18) contains amarket overview ofprotocol analyzers.This includes detailedreports on WGLinkView PRO, theLANchecker and theWG Domino serieswith DominoGigabit.

For this issue ofgateway and more, seewww.gateway.de.

The Wavetek 4400 MMobile Radio Testerwas a big eye-catcherin the December/January issue ofTest & MeasurementEurope. To visit thejoint web site with itscompanion publicationTest & MeasurementWorld, seewww.tmworld.com.bits 8402

The Internet and the many ªIntranetsº ± internalnetworks operated by large corporations ± arethe major driving forces behind the burgeoningdemand for communications bandwidth.Future forces will include telephony and videovia IP (Internet Protocol). Discussion of thebest transmission technique has divided usersinto two camps: ATM vs. Gigabit Ethernet. Oneadvantage of OC-48c is that it unites the datastreams at a higher hierarchy level.

How Do You Test OC-48c?

For long-haul traffic, there are two majortransmission techniques nowadays. ATM(Asynchronous Transfer Mode) offers scalablebandwidth and transmission quality that can beguaranteed. PoS (Packet over SONET) isoptimized for transporting IP data.Both techniques use a transport network thatprovides transmission from point A to B. InNorth America, this is SONET (SynchronousOptical Network).

Why OC-48c?

SONET's previous bandwidth limit was set by theOC-12c hierarchy level at 600 Mbit/s. OC-48cquadruples the transmission capacity to 2.4 Gbit/sand thereby offers a new and uniform bandwidthfor IP and ATM communications. The mainapplication of OC-48c involves interconnectionof ATM-WAN switches for Internet backbones,point-to-point connection for PoS applications,and interconnection of terabit routers andservers.

What is OC-48c?

The difference between OC-48 and OC-48ccomes down to a little ªcº, which stands forªconcatenatedº. 48 STS-1 SPEs (SynchronousPayload Envelopes) with a capacity of 52 Mbit/sare bunched together to produce a uniformpayload capacity of 2.4 Gbit/s. In the synchronousdigital hierarchy (SDH, used outside of NorthAmerica), this corresponds to concatenation of16 VC-4s (virtual channels) to form an STM-16cdata stream.The uniform payload capacity has the benefit thatit can be distributed much more effectively. Thiscomes near to the flexible bandwidth distributionof ATM and IP.

Why measure?

A huge bandwidth is of no use if you have toconstantly retransmit data due to transmissionerrors. Transmission quality is the key criterion forany network operator since faulty channels areusually not money-makers.

Bit error ratio tests (BERTs) in a complete payloadof a 2.4 Gbit/s channel provide the basis forassessing quality: The test pattern is apseudo-random bit sequence which fills theentire STS-48c SPE. This provides a means ofmeasuring bit error ratios and assessingperformance. Also important are connectivitytests for verifying proper configuration of OC-192networks during installation and when switchingin OC-48c channels.Here is an overview of the tests:

. Transparency test

. Performance measurements

. Overhead analysis

. Pointer analysis

. Jitter and wander analysis

. Automatic protection switching test

The OC-48c/STM-16c option, along with theOC-12c BULK and OC-12c options, turns theANT-20 Advanced Network Tester into afull-featured ªconcatenation testerº. The ANT-20is a great tool for these applications.

Stephan SchultzWavetek Wandel GoltermannEningen, Germany


PRODUCT NEWS

7

Differences betweenOC-48 and OC-48c

BERT:Pseudo-random bitsequence fills entirepayload

1669 bytes

Sectionoverhead

Pointers

Lineoverhead

166261 bytes

OC-48c

Pseudo-random bit sequence

Fix

ed

stuff

Fix

ed

stuff

OC-48c SPE

166261 bytes

46622 Mbit/s

2488 Mbit/s

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OC-48/STM-16

OC-48c/STM-16c

8

APPLICATIONS


PHOTON ± Pan-European Photonic TransportOverlay Network is the name of a projectbeing sponsored by the European Communityas part of the ACTS program. A field trial hasdemonstrated the practicality of purely opticaltransmissions including the use of opticalcross connects. The so-called MOON project ±Management Of Optical Networks ± intended

to show how such networks can be managed, isnow also a part of PHOTON.We described the technology in the previousissue, ªbits 83º, on page 14. In this article,Frank Rumpf of Deutsche Telekom'sTechnology Center describes his experiencesduring the three-month trial period.

PHOTON Field Trial:

Experiences in Combining Optical Measuring

Techniques with SDH Analysis

The PHOTON field trial has demonstrated thattransmission and routing of ªrealº signals over apurely optical network can be done reliably. Inthis case, ªrealº means SDH and ATM signalswith bit rates of up to 10 Gbit/s. Non-hierarchystandard wavelengths were also fed into thesystem using a ªleased wavelengthº. ZDF(Germany's second TV program) in Munich andORF (Austrian Broadcasting) in Vienna suppliedºliveº program signals, the BBC (BritishBroadcasting Corporation, a PHOTON partner)provided PAL coders and decoders, and theIRT (Broadcasting Technology Institute) in Munichand the TUW (Technical University, Vienna) haddirect access via fiber to a leased wavelengthfor the test. This allowed the network to be tested

with many types of signal, starting with STM-1tributaries at 155 Mbit/s, through to 270 Mbit/sDSC and MPEG data streams and 622 Mbit/s ATMsignals, on up to STM-16 tributaries at 2.5 Gbit/s.

Installation

The field trial began with recording the fibercharacteristics: loss, chromatic dispersion andpolarization mode dispersion (PMD). After theEDFAs and dispersion compensators wereinstalled, the residual overall dispersion couldbe determined. Finally, the SDH line equipmentwas connected and the transmitted spectra weremeasured.

Top: Basic networkstructure with opticalcross connect (OXC)in Passau and opticalterminal multiplexersin Munich and Vienna.For the field trials,four of the eightDWDM channels inthe 1550 nm windowwere filled: One with10 Gbit/s (STM-64),two with 2.5 Gbit/s(STM-16) and oneleased wavelength,sometimes runningat non-hierarchy bitrates.The test equipmentcomprising ANT-20and OSP-102A/OMS-100 fromWandel & Goltermannis installed in Passau.It is controlled fromthe Deutsche TelekomTechnology Center inDarmstadt.

TX/RX140 Mbit/sunframedPRBS23

Munich Passau ViennaTS 5

TS 5

SLA 16

1557.36 nm(CH 3)

2.5 Gbit/s

1550.92 nm(CH 5)

OTMX

CH 3

OXC

CH 5

OTMX

1557.36 nm(CH 3)

2.5 Gbit/s

1550.92 nm(CH 5)

SLA 16

TS 5

TS 5

Lo

op

1557.36 nm(CH 3)

P1

P2

P3

P4

Tunablefilter

1557.36 nm(CH 3)

Input Monitoroutput

Displayand

operatingunit

OMS-100

DSP

OSW-114

GPIBinterface

OSP-102A

STM-16input

ProcessorChannel

setting RX(TS 5)

Bit errorcheck

Troublecheck

Channelsetting RX

(TS 5)

Anomaly/Defect

Analyzer

Virtualinstruments

ANT-20

STM-16/OC-48test module

GPIBinterface

CATS TestSequencer

PCMCIA analogmodem interface

Darmstadt

ANT-20 remotecontrol PC

Analogmodem

TAOffice

ex-change

NT ISDN NT TA

Trial operation

The PHOTON network was tested under variousload conditions. In all cases, the bit error rate (BER)was below 10 ±19. Even under high load conditions,the optical signal to noise ratio (OSNR) remainedbetter than 28 dB (for a 0.1 nm noise weightingbandwidth). This means that there is 3 dB reserve,as the required bit error rate of 10 ±15 is reachedat an OSNR of 25 dB. Dispersion compensationwas so good that it would have been possible totransmit 10 Gbit/s at all wavelengths. Even theswitching processes in the optical cross connectsdid not generate bit errors.It was, however, apparent that even for such arelatively small network, a proper OAM structure isneeded. This point was pursued further in theMOON project which followed.

SDH measurements in a DWDMcommunications system

To measure the communications properties it wasnecessary to detect a single STM-1 carrier in theSTM-16 signal carried by the DWDM path. Thecombination of the ANT-20 Advanced NetworkTester and OSP-102A Optical Spectral Analyzerfound in the OMS-100 Optical Measuring Systemfrom Wandel & Goltermann was ideal for thispurpose. The ANT-20 was fitted with a STM-16Test Module and the OMS-100 with an additionalOSW-114 Optical Switch.

The optical measuring system was connected viathree optical couplers at the site of the opticalcross connect (OXC) in Passau. The optical switchfed one of the three DWDM signals at a time to theinput of the spectral analyzer. A tunable filter inthe analyzer made it possible to extract just onechannel from the DWDM signal. A built-in couplerin the analyzer allowed the selected channel tobe tapped off at the monitor output and linked tothe STM-16 module of the ANT-20 where it wasanalyzed as a SDH signal.

The test signal was generated in Munich using aPDH test set which output unframed 140 Mbit/spseudo-random bit sequences (PRBS, length2 23±1) in timeslot (TS) 5 of the SLA-16 system.These sequences were looped back in Viennaelectrically. The WG CATS (CVI Applications TestSequencer) software was used to analyze timeslot5 at the Passau network node. This software runsdirectly on the ANT-20.


APPLICATIONS

9

DWDM signal

SLA 16 synchronousline equipment

STM-16frame

STM-16frame

140 Mbit/sPDH signal

Opt. channel (CH)5 4 3 2

Transmission rate2.5 10 2.5 2.5 Gbit/s

Scheme for demulti-plexing a 140 Mbit/sPDH signal transmittedvia DWDM within aSDH signal

ANT-20 screen-shotmade during a bit errorrate test in timeslot 5.The lower windowshows the signalstructure made upfrom virtual instru-ments. The upperwindow shows theresult of the analysis.The bit error rate of10 ± 6 shown is due tothe PDH test set here:The test set was setto this value to makechannel 5 easy toidentify correctly.

APPLICATIONS


Measurement remote-controlledfrom Darmstadt

The Deutsche Telekom Technology Center inDarmstadt was connected to the test equipment inPassau via a modem link. A complete representa-tion of the CATS user interface was displayed bythe PC in Darmstadt, allowing all measurements tobe controlled and all results to be processed inDarmstadt. It was possible to demonstrate in thiscase that transmission in timeslot 5 was error-free.

Critical evaluation

Communications parameters and optical para-meters can be measured simultaneously using thetest setup described. However, if the signal tonoise ratio is more than 30 dB, the OSP-102Asimply indicates that this value is exceeded (30dB), because the selection method used does not

permit a greater dynamic range. OSNR values ofthis magnitude are absolutely non-critical to the biterror rate. Despite this, a comparison measurementwas made using an instrument with a differentmethod of selection.Overall, the combination of remote-controlledoptical spectral analyzer and SDH analyzer provedvery successful. Important information useful inassessing faults and for preventive monitoring,e.g. what signals were actually present, could beobtained with this test setup despite only limitedanalysis facilities being provided by the opticalelements of the system itself. The combination ofANT-20 and OSP-102A/OMS-100 proved to bevery reliable over several weeks of field use.

Frank RumpfDeutsche Telekom AGTechnology CenterDarmstadt, Germany

Wvlgth (nm) Power (dBm) S/N (dB)

1551.09 ± 8.90 430.001554.31 ± 8.90 430.001557.51 ± 9.10 430.001560.72 ± 9.80 430.00

Wvlgth (nm) Power (dBm) S/N (dB)

1551.090 ± 8.49 39.531554.282 ± 8.80 39.131557.530 ± 8.65 39.301560.722 ± 9.28 39.47

Comparison measure-ment: Results from theOSP-102A/OMS-100which uses a Fabry-Perot filter for spectralanalysis are shown onthe left; the results ofthe same measure-ment made with amonochromatorinstrument are shownon the right.

DWDM System Analyzer:

WG OSA-155

The new OSA-155 Optical Spectral Analyzer usesa grating monochromator for selection. Comparedwith its predecessor, the OSP-102A, it has agreater wavelength tuning range, better measure-ment accuracy and improved selectivity anddynamics. The tried and tested features of theOSP-102A, such as the monitor output,ruggedness and portability are all incorporatedin the new OSA-155. A CATS software packagefor operating ANT-20 and OSA-155together is already available.More information atwww.wg.com oruse the fax reply coupon.

bits 8404

Flying Hire with

Microlease

The Wavetek Wandel Goltermann UK Sales teamrecently took part in an afternoon of unforgettableairplane acrobatics with European rentalcompany Microlease.This was organized by Microlease to celebratea record amount of business between thetwo companies. During 1997/1998targets for business between thecompanies hit 168%, with the ANT-20,PFA-35, DLA-9D, OLP and OLS optics.Microlease supply electronics equipment ona rental basis to all the major telecom developers,installers and providers, among others.Microlease have been sponsors of the aerobaticsteam since 1987. The ªExtra 300Lº is flown by35 year-old former British Advanced AerobaticsChampion, Nick Wakefield, and is used up anddown the country at different air shows and eventsliveried in the Microlease colors. Flights are alsoauctioned for charity (raising up to £ 2,800 perflight) and the planes featured in a recent BBC1program.The first of its kind in the UK, it is a carbon-fiberwinged aircraft, with a 300 hp engine which drivesa special constant speed propeller to facilitate200 mph in level flight and a climb rate of 3,200feet per minute (50 feet per second). Its airframe isdesigned to sustain a remarkable 400 degrees persecond `̀ roll rateº. What all these statistics reallymean is that the passenger experiences a thrillthey'll never forget!WWGUK Account Manager, Matt Vincent saidabout the day: ªIt was a good opportunity for the

account managers to meet the Microlease team,and to celebrate the successful year we've had.I can guarantee it was an experience we will neverforget.ºMicrolease General Sales Manager,Paul McCloskey, added ªIt's a good way tocement the relationship with WWGUK. Whenyou've just climbed out of a plane that's beenflying upside down you don't forget the thrilleasily! We find our flying days really put a smile oneverybody's face and are delighted that WWGUKhave had a chance to experience this.ºFor further information about MicroleaseAerobatics visit the Microlease Web site atwww.microlease.com

PRODUCT NEWS

11W a v e t e k W a n d e l G o l t e r m a n n b i t s 8 4

The ªExtra 300Lº withthe WWGUK andMicrolease teams.WWGUK attendeesincluded: DavidWhitfield, GeneralManager; Matt Vincent,Microlease AccountManager; Jeff Cottrell,Technical ServicesManager; and AccountManagers Dave Bluett,Steve Oakman andMike Gandy fromWWGUK.Microlease attendeesincluded: PaulMcCloskey, GeneralSales Manager; NigelBrown, ManagingDirector Test &Measurement; MikeBannon, ManagingDirector, NewBusiness; and IanHolbeche, Field SalesManager.

OLP-8 for CATV.It can be combinedwith any opticalhandheld fromWandel & Goltermannsuch as the OLS-6Optical Source.

OLP-8 Optical Power Meter:

Optimized for CATV applications

High power levels on optical fibers, combinedwith rough handling, are the rules of the gameduring CATV installation work. CATV installers alsotend to be sensitive to time and cost issues.Wavetek Wandel Goltermann has designed itsnew handheld OLP-8 Optical Power Meter tomeet their specific needs: With a +23 to ± 50 dBmmeasuring range, the OLP-8 has sufficient reserveto handle even high power levels. The rubberhousing protection makes the device shockproofand waterproof. Timesaving features includesimple operation with only three buttons, auniversal push-pull adapter that handles most anyfiber, and 130 hours of usage on a single battery.The three-year calibration interval makes theOLP-8 a solid investment for the future.

bits 8405


BACKGROUND

From Dynamic Range to Measurement Range:

OTDR Standards Move Towards Reflecting

the User's Real Needs

OTDR documentation describes some keyspecifications that may be difficult to interpret andcompare in terms of customers' needs. The mainsales pitch presents the maximum performanceobtained under specific conditions, such as thedynamic range at the largest pulse width and theresolution parameters at the shortest one. Fromnanosecond to microsecond pulse widths, there isalways a trade-off between resolution andbackscatter range. We must also be attentive tosmall footnotes (at full averaging time, ondispersion shifted fiber, reflective event dynamicrange, etc.).These specifications depend on specificverification test procedures, test setup, and testconditions, and the end-user could becomeconfused as to how they apply to his/her need.Moreover, some OTDR brochures bring up eye-catching figures that describe true performancebut under specific conditions that are far from thetrue work conditions in the field. In this case,metrology standards act as a safeguard to protectcustomers' interests and manufacturers'credibility.Some OTDR specifications are clear and welldefined, but they should be considered inconjunction with other specifications to describethe product's real capabilities. Furthermore, mostof them only qualify the hardware capabilities ofthe OTDR and not its software detectionperformance.Bell Communications Research, Inc (Bellcore) hasintroduced some new OTDR specifications thatshow an OTDR's performance in a different light:

. Firstly, the procedures and test setup areinspired by field work configurations.

. Secondly, the specifications concern both thehardware and the software. They characterizethe quality of the trace displayed on the OTDRscreen, as well as the measurement accuracy.

In this article, we attempt to review and commenton how OTDR standards are evolving to reflectend-user applications, how far an OTDR can seedown a fiber (or dynamic range) and how thisparameter compares to measurement range.This article is only intended to give an outline anddoesn't pretend to be exhaustive. For moredetails, we recommend you refer directly to theBellcore and IEC standards documents.At the forefront of OTDR standards, Bellcore hasmade a considerable contribution towardsestablishing and improving metrology standards.

Bellcore supports worldwide standards activities,such as those in the Telecommunications IndustryAssociation (TIA), International ElectrotechnicalCommission (IEC) and InternationalTelecommunications Union (ITU, formerly CCITT).As an example of significant contribution,Bellcore's OTDR Data Standard for saving traceand analysis information in a platform independentformat represents a significant improvement forend-users.Today, innovative requirements like measurementrange and network resolution derived from theBellcore GR-196-CORE document (genericrequirements for OTDR-type equipment) arebeginning to appear in OTDR specifications andcustomers' requirements. These newspecifications have the advantage of beingoriented towards an end-user philosophy, but theystill show some weaknesses, and have yet todemonstrate their efficiency in gaining customer'sfavor.

Dynamic range

The dynamic range is one of the most importantcharacteristics of an OTDR, since it determines themaximum observable length of a fiber andtherefore the OTDR suitability for analyzing anyparticular network. The higher the dynamic range,the higher the signal-to-noise ratio and the betterthe trace will be, with a better event detection. Thisdynamic range is relatively difficult to determinesince there is no standard computation methodused by all the manufacturers.Dynamic range can be defined as the differencebetween the extrapolated point of the backscattertrace at the near end of the fiber (taken at theinterception between the extrapolated trace andthe power axis) and the upper level of the noisefloor at or after the fiber end. The level isexpressed in decibels (dB). The measurement isperformed with a 3 minute period for theaveraging.The upper level of the noise is defined as theupper limit of a range which contains at least 98%of all noise data points.Originally proposed by Bellcore (TR-NWT-000196),this definition was endorsed by the InternationalElectrotechnical Commission (IEC) TechnicalCommittee 86 (TC 86) Working group 4 (WG 4) inits document (IEC 61746).Another definition commonly known as the RMSnoise method (or S/N=1), is based on the usualway of representing the amplitude of a fluctuating

Event becomesaccurately

measurable

Event becomesmeasurable

Event becomesautomatically

detectable

Event becomesvisually

detectable

Noise floor

Figure 1:From dynamic range tomeasurement range

variable by its root-mean-square (RMS) value.The IEC 61746 definition (98%) seems morerepresentative, because it shows a level where thesignal visually meets the upper noise signalenvelope. But the RMS dynamic rangespecification has a huge advantage: it gives highervalues. As soon as one manufacturer began to usethis definition, others were forced to use it, in ordernot to appear to be at a disadvantage.To further confuse people, the deviation betweenRMS and the Bellcore (98%) varies strangely fromone manufacturer to another, by between 1.5 dBand 4 dB.Whatever noise definition we use, the dynamicrange only defines an attenuation loss betweentwo levels on the OTDR trace (from maximumsignal level to noise floor level). But the closer thesignal is to the noise floor, the more noisy itbecomes. For example, if we visually inspect theOTDR trace at 6.6 dB above the noise floor, wecan observe that the noise formed on the trace hasan amplitude of +0.1 dB.If we move closer to the noise floor, i.e. 3 dB, thenoise amplitude on the trace increases to +0.5,± 0.6 dB noise. The theoretical local noise levelaccording to the signal-to-noise-floor attenuationmargin is shown in Table 1 and Figure 3.In addition, the dynamic range doesn't provide anyinformation about the accuracy of the measure-ment made in this range.

Measurement range definition

Measurement range could be seen as equivalentto the dynamic range reduced by an SNR marginwhere non-linearities or noise result inmeasurement errors that exceed preset limits.According to Bellcore GR-196-CORE (issue 1,revision 2, December 1998), the measurementrange of an OTDR is defined as the maximumattenuation (one way) that can be placed betweenits optical output port and the event beingmeasured for which it can ªaccuratelyº identifythe event. Four OTDR measurement ranges aredefined:

± Splice loss measurement range± Fiber attenuation coefficient measurement

range± Non-reflective fiber end measurement range± Reflective fiber end measurement range.

For mini-OTDRs, Bellcore excludes the fiberattenuation coefficient measurement rangespecification.Today, the splice loss measurement range is themore commonly used. The test event is built tosimulate an insertion loss of 0.50 dB +0.10 dB anda reflectance of less than ± 40 dB. For an OTDRmeasurement to be considered successful, theinstrument shall provide an accurate measurementof the event in 4 of 5 attempts. The boundprescribed for loss measurement accuracy is+0.1 dB. Figure 4 shows the typical differencebetween the dynamic range and themeasurement range limits.

BACKGROUND


dB

RMS noise level (SNR=1)

km

Noise +dB

Noise ±

Local noise

Margin (dB)

Noise floor

km

Margin (dB) Noise +1) Noise ± 2)

1 + 1.06 ± 2.162 + 0.73 ± 1.103 + 0.49 ± 0.634 + 0.32 ± 0.375 + 0.21 ± 0.236 + 0.13 ± 0.147 + 0.08 ± 0.098 + 0.05 ± 0.069 + 0.03 ± 0.03

10 + 0.02 ± 0.02

dB

0.5 dB splice loss

km

Figure 2:Dynamic range. TheIEC (98%) definitionshows a level wherethe signal visuallymeets the noise uppernoise level envelope.But the RMS specifi-cation gives ªbetterºvalues.

Figure 3:Noise amplitude on thetrace

Table 1:Attenuation marginabove the noise floor1) Local noise ampli-tude above the purebackscattered level2) Local noise ampli-tude below the purebackscattered level

Figure 4:Typical differencebetween dynamicrange and measure-ment range limits

Dyn

am

icIE

C(9

8%

)

Dyn

am

icra

ng

e(R

MS

)

Attenuatorinsertionloss

Splice lossmeasurementrange

IECdynamicrange

Measurement range advantage

We have seen previously that the dynamic rangeis not totally representative of the range overwhich the OTDR will be able to detect andaccurately measure events (see Figures 1 and 4).In comparison with the dynamic range, themeasurement range takes into account the usablemeasurement domain. It doesn't only depend onthe signal-to-noise characteristic, but also on thelinearity, the distance resolution and especially onthe event detection and measurement algorithm,and its repeatability. For example, in the case of the0.5 dB splice loss measurement range, the OTDRhas to detect the splice, to be able to make a localattenuation measurement and last but not leastgive accurate results (+0.1 dB on a 0.5 dB spliceloss). The measurement range is always smallerthan the dynamic range, mainly due to thepresence of noise on the fiber following the splice,bringing uncertainty to the attenuation coefficientand consequently on the splice loss measurementaccuracy.The measurement range test setup defined byBellcore is based on realistic fiber lengthconfigurations (1 to 4 km before the event to bemeasured and only a 1-to-5 km fiber after it). Thisresults in large pulse widths of 20 ms or moreshowing poor performance. It is the reason why asignificant difference appears between themaximum dynamic range defined at the largestpulse width and the maximum measurementrange. The fact that OTDRs are not used at 20 msor more in the field confirms the relevance of themeasurement range (except in some specificapplications like submarine cables).

Measurement range limitations

If you follow the Bellcore procedure, the fourmeasurement range setups could appear morecomplex to put in place. End users could facedifficulties in checking these specifications.If you use the alternative test setup (the simplestone, Figure 5), we have to build a precise setupincluding fiber reels, a low reflectance variableattenuator (simulating a long fiber), a knownreflectance and insertion loss coupler, and areflective or non-reflective fiber end. We also haveto repeat measurements and to check the finalinsertion loss with an optical test set. The lowreflectance characteristics of the variableattenuator are of little use if the OTDR under test isnot fitted with a low reflectance input connector.

To overcome this problem, a fiber can be placedbetween the OTDR and the low reflectanceattenuator. Additionally, this fiber can be used atthe beginning of the test to measure the initialglobal attenuation (with the attenuator set tominimum) between the OTDR and the test splice.Don't think you can do it without a low reflectancesetup (attenuator and/or connectors before it)because multiple reflections, multiple backscatters(ghost signals) and attenuation dead zones willunavoidably overlap and disturb the measurementarea.If we focus on the splice loss measurement range,0.5 dB insertion loss could be considered as arealistic value for fault detection, but too large ifwe want to qualify or commission real splices withlosses smaller than 0.1 dB. Don't forget, when youbuild the 0.5 dB insertion loss event, check thevalue with an optical light source and power meter,as well as an OTDR (from one end).Splice loss measurements depend on the relativevalue of the Rayleigh backscatter coefficient of thetwo spliced fibers. To minimize this uncertainty,use fiber from the same reel and check thedirection dependence of insertion loss with theOTDR used under favorable S/R conditions (smalloptical loss budget compared to the dynamicrange).A reflectance of less than ± 40 dB could beconsidered as a realistic value, but it could alsomean that an event appears as a reflective eventusing short pulse widths, and as a quasi non-reflective event at the largest one. For example,a ± 45 dB reflectance event leads to a 13.5 dB peakamplitude above the local backscatter level for the5 ns pulse width test, and only 0.5 dB for a 10 ms(at 1310 nm) pulse. So, the choice of a particularreflectance value could optimize the eventdetection capability.These last comments show that it is difficult todefine a universal and field work representativetest setup that is able to integrate constraintsfrom submarine cable networks to passive opticalaccess networks.The figures given by OTDR manufacturers canshow differences between measurement rangeand dynamic range, from 6 dB up to 14 dB andcould lead us to think that the standard hasn'tbeen read from the same angle. The measurementtest conditions have to be carefully analyzed.Note that some customers could use an alternativesetup based on fiber looped between one outputand one input port of an optical coupler. Thisnon-standardized and controversial setupgenerates an infinite impulse response simulatinga non-ended fiber link pattern, and could convey arough but rapid idea of the ªmeasurement rangeº.

Conclusion

From a user's point of view, it is desirable to havesome form of common OTDR testing methods.OTDR calibration is continuously being improvedby the Internationals Standards Organizations.New specification terminologies and test methodsare emerging.


BACKGROUND

Figure 5:The simplest testsetup. Neverthelessit demands a lowreflectance variableattenuator, a knownreflectance andinsertion loss coupler,and a reflective ornon-reflective fiberend. Also the 0.5 dBinsertion loss eventhas to be checked withan optical light sourceand power meter.

OTDRunder test

0.5 dB

dBVariableattenuator

Among the emergent OTDR specifications, themeasurement range shows significant advantagescompared to dynamic range, and has the merit ofbeing more representative of field conditions. Thedynamic range, currently the most used, willprobably continue to be used in data sheetsbecause it leads to more attractive figures thatcatch customers attention, but it doesn't reallygive them a true idea of the OTDR's capabilities.Bellcore standards are tending towards theend-user philosophy on OTDR standardization.Whatever happens, we cannot swim against thiscurrent.Unfortunately, standards always face the samedilemma: more accurate, and they could bedifficult to use and could discourage people. Moresimple, and they could become non-representativeor could be interpreted in different ways. In bothcases, there is a danger that the standard is neverused.The market needs robust standards that aretraceable and indisputable metrology references,as well as being easy to understand and use.In conclusion, there's every chance that thedifferent definitions will cohabit for the foreseeablefuture.

AndreÂ ChampaveÁ reWavetek Wandel GoltermannSt. Etienne, France

References

[1] IEC 61746 OTDR calibration[2] Bellcore GR-196-CORE Generic Requirements[3] Guide to Fiber Optic Measurements

15

PRODUCT NEWS

New High Performance OTDR Modules

Facilitate Fiber Optic Cable Monitoring

Over 200 km Radius

Wavetek Wandel Goltermann has launched a newfamily of high performance OTDR modules thatenable fiber optic cables of up to 200 km to betested with outstanding accuracy. The newVHD family of modules are fully compatible withWavetek's renowned MTS 5100 and 5200 series ofmini and mainframe OTDRs, as well as thecompany's latest-generation Atlas remote fiber testsystem. The modules simply plug into bays in theOTDR base units, and are ideal cable analysistools for installers and maintainers of very long-haulfiber networks.The new VHD family of OTDR modules comprisesfour different single-mode models: two singlewavelength 1550 nm and 1625 nm units, and twodual wavelength 1310/1550 nm and 1550/1625 nmunits. Their exceptionally high dynamic range ±more than 43 dB for the 1550 nm modules ±facilitates very accurate discrimination of closely-spaced cable faults. The wide dynamic range alsohas a significant productivity advantage whentesting short- and medium-haul links, by providinga six-fold increase in data acquisition speed. Datathat typically took around three minutes to obtaincan now be acquired in just 30 seconds ± asubstantial time-saving when testingcables with fiber counts over 100.

The new VHD modulesare ideal for testinglong-haul terrestrialand submarine fiberoptic cables. They aresuitable for WavetekMTS 5100/5200 seriesOTDRs and the Atlasremote fiber testsystem. All modulesfor the Wavetek MTSseries testers can bechanged at any timewithout special tools.

bits 8406

bits 8407

16

APPLICATIONS


Fast data transfer over old copper wires:For error-free performance and customersatisfaction, the existing conditions must betested first. The SLK-22 Subscriber Line Testeris tailor-made for this task.

Requirements for Reliable Broadband Services:

Noise Interference Measurements on xDSL Circuits

As far as the ªlast mileº from the exchange tothe subscriber is concerned, developments intelecommunications have made little differenceup till now. Nothing much has changed, at least forprivate users, despite the introduction of ISDN.This situation now seems set to changedramatically. Why? The relative proportions ofvoice and data traffic are changing rapidly; evennow, voice traffic accounts for only about 50%of line usage. In just a few years, this will sink tojust a fraction of the present level, the Internetbeing the main reason for this change.

More data ± more problems!

The increasing volume of data traffic and everhigher transmission speeds that have becomepossible with the advent of ISDN, ADSL, VDSL andthe like is not without consequences. The hundredsof copper wires nestling together within the cablesfrom the exchanges to the subscribers wereintended for low-frequency voice signals. Theyare now required to carry higher frequency data.Capacitive coupling between wire pairs leads tocrosstalk which can impair transmissions.Increased use of such cables for datatransmissions leads to greater interference effects,particularly at the main frequencies of the linecodes used.

Do not disturb!

With modern communications methods such asADSL, the aim is to keep the sensitivity of thesystem to disturbances or interference as low aspossible. But there are limits to this, so themeasurement of line noise is an important part ofdetermining the suitability of a circuit for this typeof transmission service. Noise interference can bebroadly divided into 2 types:

. Impulse noise

. Wideband noise

Impulse noise describes transient interferencevoltages that have low power because they are ofshort duration. They may cause considerableinterference in communications systems as a resultof the relatively high voltage peaks. In contrast, theinterference voltages of wideband noise are low,but the power level is much higher because thesignal is present continuously.Different measurement methods are required fordetermining these two types of noise; the twomeasurement functions in the SLK-22 arecalled I-NOISE and W-NOISE.

Noise type Test function Test parameters

Impulsenoise

I-NOISE Peak voltage andnumber ofimpulses(mVp, count)

Widebandnoise

W-NOISE Noise power levelreferred to thetransmissionbandwidth (dBm)

Measurement of noise interference must be madeat both ends of a circuit, because the two valuesmay differ widely. The SLK-22 can perform this taskin a single measurement operation.

Examples of noiseindicators from theSLK-22 test set: ªNºfor near end and ªFºfor far end.

Bandwidth matters!

To correctly assess the effects of interference ona given system such as ADSL-DMT, the measuringset must take the transmission bandwidth intoaccount. This is done by weighting the measuredimpulse noise or wideband noise using a suitablefilter. Various filter types are specified in the IEEEstandard 743-1995:

Filter type (IEEE 743) System

E filter ISDN (BRA)

F filter HDSL-2B1Q, 2 pairs

G filter ADSL-DMT

The standard does not cover systems thatemploy a different method of transmission suchas CAP or that use a different number of wire pairs(e.g. single pair HDSL).The SLK-22 Subscriber Line Tester incorporatesa total of 16 different filter types, allowing muchmore accurate matching to system requirements,so the measurement results are a much betterindicator of actual noise performance.

Finding the fault

Some kinds of fault are much worse than others.These include intermittent faults that are verydifficult to measure and analyze because of theirtransient nature. Impulse noise caused byswitching of inductive loads such as in elevatorsor subway trains is a typical example of this.These faults can only be traced by long-termmeasurements. The SLK range of testers handlesthis task easily in AUTO STORE mode. A measure-ment time between 1 minute and 100 hours canbe pre-set on the instrument. The type of storagemode (OFF, ALL or FAIL) determines the results thatare to be recorded once the measurement isstarted. For example, in FAIL mode, only thoseresults that lie outside the permitted limit valueswill be stored.The instruments operateautomatically right up to theend of the set measurementtime for a long-term test.The timestamp recorded witheach result is a useful pointerin determining the source ofthe fault when the results areevaluated.As well as noise measure-ments, the SLK-11, -12 and-22 Subscriber Line Testersincorporate many moremeasurement facilities anda lot of advantages. Visit ourwebsite at www.wg.com oruse the fax reply coupon tofind out more.

Peter ZiemannWavetek Wandel GoltermannEningen, Germany


APPLICATIONS

The right weightingfilter is selected usingthe configurationsoftware.

Limit value and devicesettings are madeusing the configurationsoftware. They aretransferred to themeasuring device viathe COM interface.

bits 8408

PRODUCT NEWS


Ethernet and the local area networks derivedfrom it to IEEE Standard 802.3 are amongthe most widely used LANs today. Forcommissioning, acceptance testing andtroubleshooting data networks on-site, testequipment capable of handling the variousmodern network structures as well as LANcomponents such as switches and hubs isrequired.

LANchecker 100:

Active testing of Ethernet

and Fast Ethernet

The complex nature of modern datanetworks and the consistent rise in thenumber of network componentsinstalled requires powerful testequipment.Faults in the data network can lead toconsiderable bottlenecks wheredata-intensive applications involvingincreasingly fast PCs and other networkresources are concerned.Even if the electrical properties of the cablinghave been tested and certified to Category 5 onnetwork acceptance, the interplay of activeLAN components can still cause faults that leadto impaired response time behavior or todropped calls. The problems that this causesneed to be located and eliminated as quickly aspossible.Using standardized active tests according toIEEE 802.3, the LANchecker 100 can simplycheck in OSI model layers 1 and 2 for correctbehavior of the LAN, the links or the LANcomponents used.A protocol analyzer will still be required formeasurements that are mainly concerned withprotocols and applications.

Applications

The LANchecker 100 is a portable instrument formeasurements and tests on Ethernet (10 Mbit/s)and Fast Ethernet (100 Mbit/s) systems. Tomaximize on-site mobility, no further equipmentis needed.The LANchecker 100 used singly records thenetwork loading and can also be used to monitorerrors and addresses. The built-in network loadgenerator also allows the instrument to simulatetraffic and / or errors.Two LANchecker 100 instruments connected todifferent points in the network can performtransmission tests for qualifying LAN segments.This interactive testing of network segments orLAN components is also possible in-service,

not just ondisconnected

network sections.All transmission

tests are started fromand evaluated by a single

LANchecker 100. Itautomatically locates and

configures the far enddevice.

The advantages

± Fast, effective testing of 10 Mbit/s Ethernet and100 Mbit/s Fast Ethernet

± Measurement, monitoring and active testingthrough to performance optimization

± MAC and IP address monitoring± Delay time and response time determinations± Extended functions if two units are used

(echo test, collision test, round-trip delay test)± Only one operator required± Automatic testing (Auto Test)± Fast test time± Test result immediately displayed

Mobility and user-friendly operation make theLANchecker 100 a versatile tool with a widerange of applications ± indispensable for rapidassessment, optimization and monitoring of datanetworks.

Klaus ZietkowskiWavetek Wandel GoltermannWGCO Complementary ProgramEningen, Germany

bits 8409


DominoPLUS represents the next generationof the Domino family of internetwork analyzers.Interface modules can be easily swapped inand out of the chassis. In just seconds, theDominoPLUS adjusts to the type of networkit is analyzing.

Introducing DominoPLUS:

Single Chassis Supports Many

Network Interfaces

The DominoPLUSTM protocol analyzer providessingle-chassis support for a variety of LAN, WANand ATM interfaces to provide customer supportfor nine interface modules and more than 20 high-speed network interfaces. Troubleshootersanalyzing a Fast Ethernet network, for example,can now use the same tool to look at an ATM linkwith a simple swap of a card.ªThe DominoPLUS model will save significant ITdollars for network managers who previously hadpurchased multiple hardware/software solutionsto analyze different protocols and topologies,ºsaid Mike McConnell, director of LAN programsat Infonetics Research. ªThe solution also savesthe time and hassles of having to carry aroundmultiple products to diagnose and fix networkproblems. DominoPLUS will lighten the little blackbags of troubleshooters everywhere.ºThe DominoPLUS delivers laboratory-qualitypower and performance in a portable package.By employing multiple independent RISCprocessors coupled with a high speed hardwarearchitecture, all DominoPLUS interface modulesare capable of capturing and monitoring full-duplextraffic at full line rate speeds.

DominoFE gives industry's first support of FastEtherChannel

DominoFE, the DominoPLUS interface modulefor supporting both 10 and 100 Mbit/s Ethernet inhalf- and full-duplex mode, provides the industry'sfirst ability to analyze and troubleshoot FastEtherChannel network segments.Fast EtherChannel is a new high-speed bandwidthaggregation technology for connecting LANswitches, routers and servers together to providescalable and resilient switched networks. FastEtherChannel provides network managers with theability to create fast, reliable, high-speed back-bones using existing cabling and network deviceinfrastructure at minimal cost.Because EtherChannel is comprised of severallinks, the ability for complete monitoring, diagnosisand troubleshooting with synchronized time-

stamping across all links goes beyond the ability ofother analyzers on the market. The unique stackingability of DominoPLUS allows up to eight Dominoanalyzers to be stacked and controlled locally byone PC. Further, all the Domino analyzers in a stackhave synchronized time-stamps, so analysis canbe performed across segments, devices andnetworks.

DominoATM

DominoPLUS supports a wide range of ATMinterfaces, including DS1, E1, DS3, E3 and OC-3/STM-1 (multimode, single-mode, and UTP).DominoATM modules offer SVC and QoS monitor-ing and tracking as well as capture, decode andtransmit capabilities. DominoPLUS also supportsthe IMA Monitor and Analysis Application, the firsttroubleshooting tool capable of monitoring andanalyzing Inverse Multiplexing for ATM (IMA)solutions (cf. ªbits 83º, page 26).

DominoHSSI

DominoHSSI provides multiple physical interfacesin a single module. High-speed architecture allowsoperation at speeds of up to 52 Mbit/s in HSSI andup to 15 Mbit/s for all other interfaces. Support isprovided for a wide variety of WAN protocols,including PPP, router/bridge and frame relay.The HSSI interface module supports WWG's FrameRelay Application Suite for Windows. The suite al-lows a network manager to verify the operation andstability of a frame relay network to ensure theproper balance of cost versus performance.The following physical interfaces are available onthe HSSI/Multi-WAN interface module: HSSI, V.35,V.36/RS-449, X.21/V.11 and EIA-530.

Curtis JohnsonWavetek Wandel GoltermannRaleigh, NC, USA

PRODUCT NEWS

When interfacemodules are changedin the DominoPLUSchassis, the DominoWorkbench (Core)software automaticallydetects the newinterface and displaysonly those options thatare applicable for thatinterface.A benefit for DA-30ãCusers: DA-30C ATM,Fast Ethernet andHSSI/Multi-WANinterface modules canalso be placed in theDominoPLUS chassis.This offers users amigration path to theDomino platform whilepreserving theinvestment alreadymade in interfacemodules.

bits 8410

20

The IUM-10 lets you connect any ISDN protocolanalyzer to the U interface, and also enablesmonitoring of the physical line. This givesyou the means to detect and fix all types ofproblems encountered on the ISDN basic rateaccess from anywhere on the line, includingthe local exchange.

IUM-10: The Ideal Solution

for Detecting Transmission Problems

on an In-Service ISDN Line

Traditional methods of checking the quality of anISDN line are based on G.821 analysis (BERT).Unfortunately, such methods are ill-suited todetecting sporadic transmission problems sincethe line must be taken out of service during thewhole measurement interval (i.e. several days oreven weeks for rare phenomena). They alsorequire travel to put in place a tester or loopbox.A full service interruption of this sort is clearly outof the question if the access is used for businessrequirements.The IUM-10 is the ideal solution for this type ofproblem. It can be used to trace all of the eventsat the physical layer (transmission errors, lineactivation/deactivation, power supply issues, etc.)

without interrupting the serviceor traveling to the site.What is provided is real-time

decoding of events in aformat that can be

interpreted even by whopersons are not experts

at ISDN U-interfaceprotocols.Each event is

time-stamped tofacilitate correlation

with symptomsreported by the

customer.

Trace acquisition and analysis at adelayed interval

Until now, monitoring of the physical layer requiredleaving a terminal or PC connected to the IUM-10'sserial port to record the trace along the way. TheIUM-10's new software version 1.04 eliminates thisbarrier by temporarily buffering events in thedevice's memory. You can thus make long-termmeasurements without tying up your PC (or riskinghaving it stolen!). The IUM-10 has sufficientmemory capacity for several weeks of data.

Capture filters can be used to limit the quantity ofdata and speed up troubleshooting. Just downloadyour trace for analysis and archival by connectingyour PC to the serial port of the IUM-10.

More convenience with the WindowsTM PCDetailed Decoder software

The WindowsTM PC Detailed Decoder softwareis a proven companion to the IBT-10 and IBT-20testers, and can now be used with the IUM-10 too.It has the following capabilities:

± Real-time analysis and storage to disk± Delayed trace acquisition and archival on disk± Delayed analysis of a trace file± Capture and display filters

However, you can still use any terminal emulationprogram (e.g. of type ªHyperterminalº forWindows).The IUM-10 is a good solution if you want tominimize your maintenance costs (no need to travelto the site), preserve your investment (compatiblewith all existing ISDN analyzers) and reduce serviceinterruptions (in-service monitoring of a line).The new software version for the IUM-10 isavailable free of charge at: http://www.wg.com/products/ium10/ium10.html

Yann HerveÂWavetek Wandel GoltermannRennes, France

New Application Note

The IUM-10 enables physical line monitoring andconnection of any ISDN protocol analyzer at theU interface. The new IUM-10 Application Notedescribes how monitoring and analysis at theU interface allows optimization of the maintenancecosts and reduction of servicedowntimes.The Application Note presentsvarious applications:

± Remote maintenance ofISDN installations

± Maintenance of NT1swith analog accesses

± Maintenance of networkequipment directlyconnected to theU interface

± Faultfinding on thephysical layer ofin-service ISDN lines


PRODUCT NEWS

bits 8411

bits 8463

The IBT-5 is designed for use in installingISDN lines and equipment. With its multiplefunctions, it can be used to check whetherlines and equipment are working properly assoon as they are brought into service. Inmaintenance applications, it provides fastdiagnosis of problems encountered on ISDNaccesses. With its newest applications, it is acomplete tool that is in perfect harmony withthe IBT-10/IBT-20 testers and the WindowsTM

PC Detailed Decoder.

WG IBT-5: New Software Version

for ISDN Basic Rate Tester Delivers Real-Time

Tracing and Printing of Results

The addition of a serial interface to the IBT-5opens the door to new applications.

The IBT-5 lets you verify the quality of a line andthe availability of normal and supplementary ISDNservices. Oftentimes it is necessary to maintain arecord of tests performed on the ISDN interfaceand show this record to the customer. The IBT-5now has a print feature, making it easy to generatea hard-copy record of all test data (BER/G.821,tests of normal and supplementary services) usinga standard serial printer.When problems occurred while making calls orenabling supplementary services, the IBT-5'strace function was sometimes unable to fullytroubleshoot the problem. Now, however, the IBT-5connects directly to the WindowsTM PC DetailedDecoder software to allow tracing in real time.You can then analyze and store traces on yourPC for subsequent analysis or transmission toanother office. You can thus take advantage ofthe power of the WindowsTM PC DetailedDecoder software for decoding ISDN signalling.The software is also compatible with theseproducts: IBT-10, IBT-20, IST-15 and IUM-10.Wandel & Goltermann offers a global solution foryour ISDN network analysis and troubleshootingissues. Whether you're working with the S0/T0, S2/T2 or U interface, we have a solution to meet yourneeds.

WG IBT-5/-10/-20:More proprietary protocols nowavailable (Q.SIG and CorNet)

All of the testers in the IBT product line support theQ.SIG protocol in TE (terminal) and NT (network)simulation modes. The IBT-5 and IBT-10 provide TEsimulation for the CorNet-T protocol.In the area of proprietary protocols, the IBT productline now has two new test solutions:

Testing on the basic rate access for terminalsconnected to interface type Up0/E

For use when installing and maintaining basicrate accesses using a Siemens proprietary inter-face of type Up0/E (PBX HiCom 300E), the IBT-5now includes the CorNet-TS protocol used for thistype of connection.

Interconnecting PBXs (basic and primary rateaccesses) with CorNet-N/CorNet-NQ and Q.SIGprotocols

IBT-5 (basic rate tester) Q.SIQ, CorNet-T, CorNet-Ts

IBT-10 (basic rate tester) Q.SIQ, CorNet-T, CorNet-N, CorNet NQ

IBT-20 (primary rate tester) Q.SIQ, CorNet-N, CorNet NQ

A new test solution for interconnected PBXs(basic or primary rate access) using the CorNet-N/CorNet-NQ and Q.SIG protocols is now available.The solution comprises TE and NTsimulationfunctions for the IBT-10 and IBT-20 devices aswell as the WindowsTM PC Detailed Decoderapplication for protocol analysis. You now haveaccess to complete decoding of the CorNet-N/CorNet-NQ and Q.SIG protocols, including detailedanalysis of supplementary services.

Hubert ChartinWavetek Wandel GoltermannRennes, France

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PRODUCT NEWS


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AO/DI (Always On/Dynamic ISDN) is a newway of using ISDN for Internet access, remoteaccess and other applications involving variablebit rates and lengthy connection times. AO/DIis undergoing deployment in many countriesthroughout the world.

WG DA-5: The First Protocol Analyzer on the Market

to Support AO/DI

AO/DI: An up-and-coming major technology

Public telephone networks were initially conceivedto handle telephony, i.e. voice communications,and the underlying assumption was that theaverage phone conversation only lasts a fewminutes. Now, with the explosion of the Internetand telecommuting, almost 50% of the trafficcarried by public networks is data. But connectionsto the Internet or a remote enterprise networkgenerally last from 10 minutes up to several hours!The result: Network saturation and performancedegradation for all of the users.

AO/DI (Always On/Dynamic ISDN) was inventedas a solution to this problem. AO/DI involves usingthe packet-mode transmission capacity of the Dchannel to provide a permanent virtual connection.The speed of this connection is sufficient forexchanging electronic mail, viewing news, emulat-ing a terminal, etc. The connection does not blockup any circuit resources in the public network

since the packets are transmitted directly to theservice provider or to the remote network via apacket-switching network, without passing throughthe public exchange. When traffic grows beyondthe capacity of the permanent virtual connection,one or two B channels are set up to increase theavailable bandwidth. Telecom operators are notthe only ones to benefit from this better usage ofnetwork resources. End users have addedconveniences (such as being informed in realtime of the arrival of an email via the permanentvirtual connection) at a lower cost. And serviceproviders (e.g. Internet) can handle moreconnections (i.e. more customers, more revenue)using the same number of access ports on theirconcentrators.

But: Suitable test means are required!

In order to implement AO/DI in routers andconcentrators, install such equipment, verify thatthe service is actually available and detectproblems during maintenance work, a suitableprotocol analyzer is required. AO/DI is a complextechnology using various modes of transmission(packet and circuit switching) and sophisticatedprotocols (ISDN signalling, X.25, PPP/MLP, BAP/BACP, etc.). A single configuration error in one ofthe many parameters (ISDN addresses, X.25packet size, B-channel opening threshold,authentification parameters, etc.) can render theservice unusable and cause performance problems(B channels never opened) or, worse, generatehuge bills (B channels continuously open)!

WG DA-5: A unique solution for AO/DI

The DA-5 is a compact, rugged and easy to useanalyzer with an exceptional price-to-performanceratio. With its new software version 2.06, the DA-5is now the first tester capable of simultaneouslyanalyzing all of the protocols used by AO/DI in theD and B channels (see figure). The ability tosimultaneously decode the D and B channels isparticularly important for understanding problemsinvolving dynamic bandwidth allocation.Frames are decoded in real time and can be savedon disk, enabling long-term data capture. TheDA-5 supports most of the existing ISDN signallingprotocols and can be used on the S/Tor U interface(with the WG IUM-10).

PRODUCT NEWS

BAP/BACP TCP/IP (data)

PPP/MLP

Q.931 X.25

Q.921

D channel B1 channel B2 channel

Q.931: ISDN signalling, layer 3

Q.921: LAPD (ISDN layer 2)

PPP/MLP: Point-to-point protocol with multi-link option. ThePPP multi-link group includes the X.25 virtual circuit(which is actually the primary link) plus additional Bchannels which are established if necessary.

BAP/BACP: Bandwidth allocation protocol/Bandwidth allocationcontrol protocol. Protocol to control allocation andrelease of B channels.

Version 2.06 includes other improvements suchas complete decoding of the PBX interconnectionprotocols Q.SIG and CorNet. This is just anotherbenefit for network managers who must handlemixed voice/data configurations.This new version is compatible with all existingDA-5s. You can download it free of charge fromwww.wg.com/products/da5/da5.html.

Yann HerveÂWavetek Wandel GoltermannRennes, France

Broadcasters are Committed to Quality of Service (QoS)

with the DTS-400P Digital Broadcast Monitoring System

Digital broadcast services by satellite range fromdirect broadcast TV for the general public to dataor enterprise services for professionals andcompanies. Satellite operators and broadcastservices from telcos run hundreds of services ondozens of multiplexers. From their satellite uplink,they feed the channels and transponders ofseveral satellites to finally reach millions ofsubscribers.After successfully launching these services,satellite operators are now committed to providinghigh QoS to their customers. By deploying thedigital broadcast monitoring system, theoperator is able to:

± Easily locate errors± Troubleshoot them remotely± Limit mean time to repair (MTTR).

By continuously monitoring the broadcast network,the satellite operator now has tools to defineservice level agreement (SLA) with providers orcustomers, to trace and to commit themselves toit. In a typical configuration including dozens ofMPEG-2/DVB transport streams, a satellitebroadcaster reviews the quality and conformanceof the signals before transmission on the uplink,and checks the availability of the service on thedownlink in the same reception conditions as hiscustomers. Under this configuration, the digitalbroadcast monitoring system offers uniquefeatures such as:

± Visibility of the complete broadcast system on asingle screen

± Immediate access to detailed troubleshootingon any MPEG-2/DVB stream

± Traceability of alarms and errors.

Alarms and error detection are user-customizableand the system will easily include new streams ornew features by simple software downloading. Forthe benefit of the operator, the investment is along-term one providing immediate return fromcustomer satisfaction and improved reliability ofthe broadcast system.

Jean-Pierre HeÂ notWavetek Wandel GoltermannRennes, France


APPLICATIONS

For more information:www.via-isdn.org/always.sonnet.com/isdn.wg.com/

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Digital broadcast is today one of the mainfocuses of all consumer electronic companies.At a time where almost each and every home isover-equipped, digital broadcast is introducinga new need into the consumer market:To connect their existing TV set to the digitalsignal from cable, satellite or soon, fromterrestrial networks, a digital integratedreceiver decoder (IRD), commonly known as aset-top box, is needed.

Digital Broadcast: Set-Top Box Customization

Set-top box manufacturers are faced with adifficulty: Although there are standards such asDVB or ATSC which have been widely adopted,there is unfortunately no ªstandardª stream beingbroadcast! This does not mean that they are notDVB compliant in terms of multiplexing, synchron-ization, etc, but the fact is that they all containsomething that is specific to the broadcaster:

± The electronic program guide (EPG)± Conditional access information± Private tables± OpenTV ã (or other engines)

interactive applications± Data applications, etc.

As a consequence, set-top boxes need to bespecially designed, or at least customized, to meetbroadcaster requirements, and then of course,tested and validated.

Getting the right streams to test set-top boxes

The first issue when customizing set-top boxes isto get the right streams to test them. Manyreference stress patterns are available on themarket or on the Internet but only provide for basictests. Furthermore, stream creation tools, whichare necessary to build ªtheoreticalº streams, neverallow the user to cover all possible real-worldconfigurations.

So the first need for set-top box manufacturers isto get some sample streams of the broadcasterthey want to work with. But when you're an Asianmanufacturer working with European broadcasters,the only way to get these precious samples is togo abroad to record the streams.The ideal solution for this is then a portable trans-port stream recorder such as the WG DTS-G(P)which is already used by many manufacturersworldwide.Among other features, it provides for the following:

± Recording of MPEG-2/DVB and MPEG-2/ATSCtransport streams

± Recording of terrestrial, cable and satellitestreams, including new transponders at45 Msymbols/second.

± Recording of large files: A total of 18 Gbytes canbe stored on the equipment, and downloadedon a server later on via Ethernet.

± Time-stamped capture: All captured packets aretime-stamped, which means it will be possibleto play back the transport streams under theexact recording conditions, including data ratevariations on asynchronous serial interfaces(DVB ASI).

As a user usually wants to check the content of thestream prior to recording it, real-time analysiscapabilities can be added, leading toWG DTS-AG(P) or WG DTS-A2G(P) configurations.This provides for on-line viewing of all MPEG-2/DVB PSI/SI tables down to the descriptor level, aswell as OpenTVã modules.

Testing channel hopping using WG DTS-2G(D)

The recorded transport streams can then beplayed at the input of a set-top box, or at theinput of a standard modulator and then passed tothe set-top box, making it possible to validate thehardware and software design as regardsdemultiplexing, decoding and running interactiveapplications.But validation teams within set-top box manu-facturing companies usually have further needssuch as channel hopping testing.In a complete digital broadcast bouquet, e.g.satellite, around 10 transport streams are simul-taneously broadcast. The integrated receiver


APPLICATIONS

WG DTS-G(P):Portable TransportStream Generator(record/play)

decoder uses the MPEG-2 program specificinformation (PSI) inserted by the broadcaster tolocate a program in a transport stream. But inorder to automatically locate a program in a bunchof transport streams, the IRD will have to makethe most of the DVB service information (SI). Forexample:

± The network information table (NIT) will givesome information to the IRD about themodulation schemes and parameters.

± The service description table (SDT) will givesome information to the IRD about the programnames, the conditional access system which isused.

± The EPG information can be carried in the eventinformation table (EIT) or in private tables.

This information, once collected, will allow the IRDto automatically perform channel hopping whenreceiving a viewer request via the remote control.In other words, this will allow the IRD to changefrom one program located on the actual transportstream to another program located on anothertransport stream in a way which is fully transparentto the end-user.The only way to test that a set-top box supportschannel hopping and offers fast response time is toemulate the network by simultaneously generatingtwo transport streams previously recorded.

This can easily be done using a DTS-2G(D),passing the streams to modulators tunedaccording to information included in the NIT.Today both DTS-G(P) and DTS-2G(D) are used bymany set-top box manufacturers around theworld, making it possible for them to reduce theirvalidation time, and as a consequence, acceleratetheir ªtime to marketº.

ReÂ gis Le RouxWavetek Wandel GoltermannRennes, France


APPLICATIONS

Demodulator

Transport stream

WG DTS-G(P)record mode

WG DTS-G(P)playback mode

Transport stream

ModulatorIRD under test

Monitor

Getting the rightstreams usingDTS-G(P)

Testing channelhopping usingDTS-2G(D)

WG DTS-2G(D)

Transport stream #1

Modulator #1

Transport stream #2

Modulator #2

Mix

IRD under test

Monitor

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With increasing competition within the tele-communications market, together with newenabling technologies creating a wider choiceof services at highly competitive prices, today'send users are demanding and expecting higherlevels of service quality from their serviceproviders. As a result, service providers are nowoffering improved ªpremium gradeº servicescoupled with Service Level Agreements (SLAs)which set out target levels of network andservice quality commitment in order to retaincustomer loyalty, avoid penalties and to attractnew business.

WG QMS: Making

Service Level Agreements

Manageable

The setting up of an SLA demands a high standardof network availability and performance which isenabled through improved quality managementsystems. Operators require more robust networkprovisioning with complete end to end visibility ofnetwork and service performance to achieve thedesired levels of service quality and complianceof the SLA contracts to their end customers.Wavetek Wandel Goltermann has recognizedthe need for centralized test managementspecifically aimed at providing end to end solutionswithin an open systems platform environment.WG QMS (Quality Management System) with itsSLAV (Service Level Agreement Validation)application offers automated validation ofcustomer network leased line performanceagainst SLA contract targets. WG QMS performsreal-time network performance and alarmmanagement giving operators advanced warningof impending SLA violations. Alerts can be sentusing a wide range of media including pager,E-mail, fax, visual and audible messaging.Management reports and end customerstatements of compliance can be automaticallygenerated by the system, which has a freeformreporting tool enabling customized reports to becreated by the user.

WG QMS is based on a CORBA architecture(Common Object Request Broker Architecture)which is scaleable from a single server stand-alonesolution through to a distributed multiple serverand multi-user system. By choosing a robust SUN/UNIX based server coupled with Microsoft NTTMbased PC clients, WWG has created a world-classservice quality and fault management combinationoffering dependability with ease of use. The heartof the QMS is the Sybase SQL Server DBMS.This tried and tested database manager creates


PRODUCT NEWS

Figure 1: End to enddigital E1 leased lineperformancemonitoring usingCELOGIC QT 100Bequipment at thecentral office andQT300B remote probesat the customerpremises. This methodutilizes out-of-channelcommunicationthrough the E1 circuitbeing monitored,enabling extendedªreach throughº in theaccess network whileconsiderably reducingthe cost of deployingremote probes at thecustomer site(removes the need forexpensive dial-upequipment).

WG QMS reduces SLApenalties and customerªchurnº by improvingservice performanceand visibility.WG QMS pays for itselfin months offering realvalue investment ratherthan further cost.

WG QMS

SAP SAP

CPE

QT300B

Customer premises

QT100B

Central office

QT300B

Customer premises

SAP = service access pointCPE = customer premises equipment

CPE

a reliable core for QMS where all transactionsand results information are managed acrossa distributed environment. Database replicationis an option which enhances the scope of theQMS system adding more security androbustness.In addition, PC client remote user access isalso possible through a Web browser. TheJAVA based light client software enables thefull QMS GUI to be displayed on a remote PClinked to QMS through a corporate Intranet.The UNIX server can be located in a securelocation for reliability.System interworking with other NMS is alsoprovided for through open standard interfacesand MIBs. For example both the TMN (CMIPover Q3) and OSI (SNMP) environments can besupported through protocol agent functions.As default, WG QMS uses SNMP over TCP/IPas a standard protocol to communicate with theremote test units (RTUs). Other communicationprotocols are supported such as dial-up usingPPP, ASCII based craft interfaces or TL1 forinterfacing to other network or test elements.One family of RTUs supported are theQUALITRANS probes from CELOGIC, a WWGstrategic partner company offering probehardware specifically designed for end to endquality of service management.Remote fault management is supported throughuser-programmable test sessions and test objectswith a powerful scripting editor tool allowinguser-configured test procedures and additionalelement drivers to be written. A configurationmanager is provided for rapid configuration of thewhole SLA validation system.

To discuss WG QMS further contact: Phil Bull(Systems Marketing Manager)+44 (0) 1752 765326 e-mail: [email protected] orBob D'Silva (Business Development Manager)e-mail:[email protected]


PRODUCT NEWS

Key features of WG QMS

. End to end customer and service orientation

. Scaleable and distributed CORBA architecture

. Network and test element configuration manager

. Security and audit trail management

. Performance and alarm manager with user definable filters andalerts

. SLA validation application provides service status to help desk andend customer

. A fault management tool based on ITU-T X.745 providesinteractive testing through test sessions and objects. Both analogand digital testing can be supported with remote test units.

. Robust UNIX QMS server

. Microsoft NTTM (and 95/98) PC and/or UNIX client and Webbrowser (JAVA) user access

. Open systems compliant through TMN and OSI interfaces

. Easy to use graphical user interface (GUI)

. Supports a wide range of remote test units (RTUs) from WWGand 3rd parties.

. SyBase SQL Server DBMS for industry-proven reliability

WG QMS user profiles supported:

. Front desk and back office users at customer support centers

. Network management users at international or national operationcenters (NOC)

. Operational users at regional centers

. Maintenance users at local sites, centraloffices and customers premises

Customer service center

A B C Customer

Sub-network(end-to-end service)

Region

Location

Circuit group

Circuit

Service point(network element)

SAP

SIPSIPSAP

Figure 2: Shows therelationship betweenthe four businessfunctional layers asdefined in theTelecommunicationManagement Network(TMN) specification andthe various user viewssupported by WG QMS.Each type of user isgiven a different sub-set of data appropriateto their needs asmarked by Views 1to 3. Multiple userscan access the datasimultaneously.

Business

Service

Network

Element

Front office

View 1

Operations View 2

Maintenance View 3

QT100B

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Documents

Wavetek Wandel Goltermann: The New Logo GSM Network Optimization · PDF fileSDH Network? Path trace analysis becomes increasingly critical when multiple providers are involved in signal