Designing and setting up a new local area or wide area network (LAN or WAN) can be an enjoyable—but also formidable—task. Expanding an existing network poses even greater challenges, since implementation strategies are constrained by the present network topologies, equipment and traffic-handling capability.
But whether you are commissioning a new network or updating existing facilities, it is essential that network designers and test professionals interact and cooperate. To achieve the appropriate results, these are the tasks to be performed:
Physical installation checkout.
Functional verification.
Performance validation.
Fortunately, a multitude of application- or network-specific and general-purpose test equipment is available to perform these tasks, some of which also help gather information for network extension planning. For instance, the RC-200-C ATM Analyzer with Signaling Simulation software allows you to add virtual users to the existing network and evaluate its efficacy, said Ari Zamir, President of RADCOM.
Following planning and installation, a variety of test equipment is available for equipment and interconnection checkout. For wired interconnections, they range from continuity testers to loss test sets to time domain reflectometers (TDRs).
A TDR verifies the integrity of the cable received (on a spool) and subsequently locates cable faults that cause performance problems. But many test professionals hesitate to rely on TDRs since accurate results depend on knowing the cable’s propagation constant and correctly setting gain and pulse width.
This is no longer the case with some new TDRs. For example, the Tektronix TV110 performs automatic calibration and setup with minimal user involvement.
“You only need to know the name of the cable (by brand or type), enter it into the TDR and it measures the distance to fault accurately,” said John Breeden, Product Marketing Manager, Cable Network Analyzers at Tektronix. “No adjustments are necessary and the user interface is simplified to pressing a less cable or more cable softkey to evaluate near or distant defects.”
Frequency domain reflectometers (FDRs) are an alternative to TDRs for some applications. FDRs provide indications of standing wave ratio (SWR) and return loss of cables, connectors and wireless LAN antennas.
To accommodate high data rates, many of today’s networks use fiber optics as the interconnection media. Optical TDRs (OTDRs) are used in this case to find fault locations and laser sources and power meters are used to perform loss measurements.
Good record-keeping of cable runs, terminations and performance parameters is essential for maintenance and upgrading. Software packages simplify this task. For example, FOdoc (for fiber) and WireDoc (for copper) software from Fotec aid planning, provide connection diagrams, file corresponding test records and prepare path reports.
After interconnections are checked and interfunctionality verified, traffic and signaling simulators as well as network emulators facilitate performance assessment of each piece of equipment or the entire network. Some of these tools are network-and termination-specific, others are multifunctional or configurable to serve many applications.
To assist you in selecting the appropriate equipment for your network installation checkout or maintenance tasks, here is information on a variety of products.
Network Test Equipment Products
Wiring, Cabling, Transmission Line Test Products — subhead
Coaxial TDR
Has <1" Resolution
The BiddleÒ Model 531 Coaxial Time-Domain Reflectometer (TDR) analyzes cables and locates shorts, opens, high-resistance taps, wet taps and impedance mismatch along the transmission line, and attenuation and return loss on coaxial cable systems. Resolution is better than 1″ so activity along a cable span can be viewed. The maximum resolution is 10,000 ft. The zoom capability enables trace expansion at selected points. The 531 features 15 internal memory registers which retain data until overwritten. $3,650. AVO International, (800) 723-AVO-1.
Test Set Checks
UTP/FTP/STP, Coaxial Wiring
The DXB66 Professional Test Set verifies the integrity and functionality of LAN cabling and premise wiring. It has two RJ45 jacks for continuity testing of four-pair EIA/TIA 568 wiring schemes, including the shields of foil twisted pair and shielded twisted pair cabling. A BNC coax test checks Ethernet 10Base-2 buses; adapters accept token ring-style connectors. Master and remote units interlock for testing patch cords and separate for checking premise runs. $149.95. L-com, (800) 343-1455.
Transmission-Line Test Set
Offers Four Instruments in One
The 186T Analog and Digital Transmission-Line Test Set combines the functions of four instruments into one hand-held unit. In addition to testing transmission lines, it provides TIMS, Bridge/135/600 ohms for digital and analog testing, an autoranging DMM and telephone handset functions. The 186T is compliant with IEEE 743-1984 (Bell Standard 41009) and is designed for field testing of voice and data (two or four wires) telecomm circuits over a range of 20 Hz to 50 kHz. $1,975. American Reliance, (800) 654-9838.
Cable and Antenna Analyzer
Rejects External Interference
Four models added to the Site Master SWR/Return Loss Analyzer line offer segmented coverage from 25 MHz to 3,300 MHz. Site Masters measure SWR, return loss and distance-to-fault on analog and digital RF transmission lines. The models reject external RFI, a requirement for HF communications applications such as paging, cellular and PCS. Site Master isolates transmission faults using frequency domain reflectometry, which can locate RF faults, not just DC open- or short-circuit conditions. $4,900 to $6,950. Anritsu Wiltron, (408) 778-2000.
Fiber Optics Test Products
Dual Wavelength Laser Source
Has Single Output Connector
The RIFOCS 262A Dual Wavelength Laser Source provides calibrated laser outputs in the 1,310-nm and 1,550-nm ranges. Both outputs are available from a single port, obviating the need to disconnect and reconnect when switching between lasers. A universal connector interface (UCI) accommodates industry-standard fiber-optic connectors via a line of screw-on/screw-off UCI adapters. Three modulation frequencies are offered. Typical applications include connector-loss testing, evaluating single-mode fiber-optic links and continuity testing. $3,400. RIFOCS.
Fiber-Optic Test System
Integrates Multiple Instruments
The IQ-203 Fiber-Optic Test System is a modular 486-based mainframe that houses up to three user-interchangeable modules and controls up to four IQ-206 expansion units. Each IQ-206 accepts up to six modules, all controlled through Windows. The IQ-Application software provides turnkey access to achieve automated acquisition, compilation, analysis and storage of relevant data. Applications include insertion loss/return loss for 1 x N splitters, multiple DUT testing, source-power applications and bidirectional component testing. EXFO E.O. Engineering, (800) 663-EXFO.
Fiber-Optic Test Kit Offers
Simplified Data Logging
The Fotec Lite Test Kits include equipment to test fiber-optic networks and cable plants. The kits feature dual wavelength capability. The T570 kit for multimode fiber has 850-nm and 1,300-nm LED sources; the T595 kit for single-mode fiber has 1,300-nm and 1,550-nm lasers. Kits combine a Fotec Smart FO power meter with a mini light source. Accessories and the FOtest Lite software for fiber-optic test and data acquisition are included. T570: $1,395; T595: $3,300. Fotec, (800) 537-8254.
Optical Test Set Features
Integrated Voice Com
The new OTS family is comprised of an 800-nm to 1,600-nm optical power meter; optical sources emitting 1,310-nm, 1,550-nm and combined 1,310/1,550-nm signals; and loss test sets combining the power meter and optical sources. The hand-held units are ruggedized, water-resistant and offer an optional talk-set capability so installation/maintenance engineers can communicate verbally over the fiber-under-investigation. Amplitude modulated signals simplify identification of which fiber in a cable is being tested. Wavetek S.A., 011 33 77 47 8900.
Network Equipment and Services Test Products
Hand-Held T-1 Test Set
Features Remote Operation
The EZ-TESTER is a hand-held T-1 test set for functional verification and performance validation of network services. It includes capabilities to place calls and test services from a T-1 interface in a conventional or an ISDN network. Options include fractional T1 operation, on-screen pulse-shape analysis, ESF/SLC-96 monitoring and control, and computer-enhanced testing. When operated unattended, it logs events with a date and time stamp. Remote operation is supported via a WindowsÒ software package. $4,495. Electrodata, (800) 441-6336.
Options, Enhancements Added to
SONET Maintenance Test Sets
A new option for the HP 156MTS Synchronous Optical Network (SONET) Maintenance Test Set supports SONET STS-12c clear-channel and STS-12c/ATM service tests. The test set has been enhanced to support C2 verification. A new STS-12 test option performs full-bandwidth SONET STS-3c and STS-1 clear-channel bit-error-rate test (BERT) testing within OC-12 signals. A standard suite of BERT patterns allows you to verify performance of the full bandwidth payload, and an alarm generation feature lets you check and evaluate status conditions. Options start at $9,950. Cerjac, Division of Hewlett-Packard, (800) 452-4844, ext. 1817.
Instrument Views Network
Events by Protocol Category
The HP Internet Advisor for LAN Series provides monitoring and analysis for Ethernet, fiber distributed data interface (FDDI) and token-ring networks. The HP J2522B is the Ethernet version, HP J2523B is for the Ethernet/token-ring network, and the HP J2524A is the FDDI analyzer. The series offers graphical presentations of network health with real-time parameter summaries. An expert-commentator feature allows access to an information base for solving network problems. Network stack decodes show all fields of all major protocols, including Novell, TCP/IP, AppleTalk, Banyan, OSI and DECnet. HP J2522B: $16,000; HP J2523B: $21,000; HP J2524A: $22,000. Hewlett-Packard, (800) 452-4844. ext. 1334.
Hand-Held Unit Tests
Physical Layer Nonintrusively
The LANMaster™ 100 and the LANMaster 100RS Data Clamp with an RS-232 interface are hand-held LAN traffic monitors. They provide nonintrusive tests for active networks, and diagnose and identify network, application or end-user problems. Compatible with UTP, STP and coaxial cables, the products clip on top of network cables to provide a readout of bandwidth utilization. Inductive sensors work with Ethernet and token-ring networks. Network activity is logged and recorded from 12 min to 24 h. LanMaster 100: $749; LanMaster 100RS: $899. Harris, Dracon Division, (805) 987-9511.
Hand-Held Analyzer Monitors
Packet Exchange to File Server
The NETcat™ 2000 Series Testers are PC-controlled hand-held analyzers for diagnosing and troubleshooting Ethernet problems such as slow network response. The analyzers monitor packet exchange between a station and file server, and display the cause of a connection failure. The NETcat 2100 provides a wire map of 10BASE-T cable and detects broken or intermittent wiring, crossed pairs, reversed pairs, opens and shorts. The NETcat 2200 checks UTP, STP and coax cables for conformance to network standards. 2100: $1,795; 2200: $2,995. Datacom Technologies, (206) 355-0590.
100-MB Ethernet Analyzer
Includes Expert Software
The FastLAN 900, a 100-MB Fast Ethernet product, is a new member of the LAN 900 Expert Series of 10-MB Ethernet and the 4/16-MB token-ring LAN protocol analyzer products. The FastLAN 900 system with Real-Time Expert Analysis proactively detects network and protocol problems and recommends solutions. It analyzes frames and broadcasts, performs real-time decodes and includes remote- control capabilities. The Ethernet and the token-ring version comprise a 16-bit, half-size PC board with software. $5,900. Digitech Industries, (203) 797-2676.
LAN Meter Accesses Information
Stored in Information Bases
The 68X Enterprise LANMeter Series tools troubleshoot complex segmented networks and access information stored in the management information bases and remote-monitoring agents via the Simple Network Management Protocol (SNMP). The meters help sense across a router and determine LAN/WAN link performance. NetBIOS protocols are supported. The segment-discovery test analyzes attached segments, giving a list of available SNMP agents. $8,495 to $11,495. Fluke, (800) 44-FLUKE.
Portable Protocol Analyzer
Uses PC Serial Port
The Model 904 PC Comscope™ provides the capability of a communications data-line monitor, an emulator and a bit error rate tester in a portable configuration. It can be added to any PC by connecting the supplied cable to the serial port without requiring configuration. The embedded coprocessor monitors and emulates data lines to 64 kb/s on a full duplex basis. It supports most asynchronous, synchronous and bit-oriented WAN protocols such as BiSync, IPARS, HDLC, SNA and X.25. $499. Telebyte Technology, (800) 835-3298.
ATM Test System Analyzes
Signaling and LAN Emulation
The ATM Expert System automatically detects and highlights signaling and LAN emulation error sources and measures ATM switch performance based on time to setup and teardown calls. It also provides the correlation between legacy LAN addresses and ATM addresses for statistics and troubleshooting. These measurements help determine the source of networking problems, verify that the network is fine-tuned, and perform equipment evaluations. The Expert System runs under Windows on RADCOM’s line of ATM and ATM/WAN/LAN analyzers. $3,000; no upgrading charge. RADCOM Equipment, Inc., (201) 529-2020.
Instrument Provides Tests
For ATM, DS3 and SONET
The DS3 ATM option for the T-BERD 310 Communications Analyzer performs ATM switch and network facilities tune-up and maintenance for DS3 and SONET networks. The option adds DS3 ATM testing to the SONET, DS3, DS1/0, fiber-optic media and OC-3 test capabilities provided by the T-BERD 310. The option also offers in-service and out-of-service testing for ATM switches and network facilities by generating and analyzing cells at DS3 rates. It checks QoS parameters, including cell loss, cell misinsertion and round-trip delay. T-BERD 310: from $9,995; DS3: from $4,995. Telecommunications Techniques, (301) 353-1550.
Configurable Analyzer Assesses
Internetwork Performance
The DA-30C Internetwork Analyzer decodes, captures and simulates traffic on any two LAN, WAN or broadband (including ATM) segments simultaneously. A multislot backplane accepts up to four plug-in interfaces. Application software, running under a graphical user interface, performs real-time monitoring, traffic generation and device benchmarking. Typical application-oriented software includes RTBench for measuring internetwork performance of bridges/routers, STBench for multiport-device benchmarking of Ethernet switches, and the ATM SAR Utility for conversion between cells and frames using ATM AAL segmentation/reassembly. From $17,995. Wandel & Goltermann, (919) 941-5730.
Hand-Held Analyzer Provides
ATM Test Capabilities
The OC3/ATM Analyzer with OC3port™ plus provides ATM service-testing, equipment-verification and troubleshooting capabilities. It simulates ATM traffic and OAM support. The hand-held instrument combines a full set of physical-layer SONET test capabilities with an ATM test set to isolate and diagnose network problems. It features eight programmable ATM transmit cell streams, CBR, VBR-Burst, VBR-Poisson and PDU-Poisson traffic-simulation models. $11,995. DeskNet Systems, (914) 273-6232.
Protocol Analyzer/Emulator
Tests all ATM Levels
The INTERVIEW 8750 ATM EXPRESS and INTERVIEW 8800 PLUS ATM TURBO Protocol Analyzers/Emulators fully monitor and analyze ATM user/network interface protocols at all levels in real time. The testers support DS-3, E3, STS-1 and SONET/SDH OC-3c interfaces. They support several decodes including AAL 1, AAL 3/4, AAL 5, UNI 3x, ITU-T Q.2931, SAAL signaling, RFC 1483, CLNAP, ILMI, RFC-1577 and LANE. CBR analysis provides cell-level and circuit statistics. Robust filtering can be performed on any field or element of the protocol stack. INTERVIEW Series from $9,950. Telenex, (609) 234-7900.
LAN/WAN/Broadband Network
Test Set Supports New Features
The Chameleon Open provides simultaneous full bandwidth testing of communication equipment as well as LAN/WAN and broadband networks. It supports multiple LAN and WAN interfaces connected to different mediums and traces user applications as they transition through network segments. Application modules for ATM, SMDS, frame relay, X.25, ISDN PRI, Ethernet, token-ring and FDDI testing are available. New features support DS-3 frame relay and SMDS DXI services and enhanced simulation/analysis capabilities to evaluate the latest ATM standards. From $22,000. Tekelec, (818) 880-5656. ISDN Tester Verifies Dual
The Version 3.0 Firmware for the CT-100 CrafTek Subscriber Loop Test Set provides a dual B-channel call-control capability, allowing both channels to be tested simultaneously. New features include Easy Configure and Easy View software. The rugged, portable CT-100 verifies the ISDN subscriber loop by emulating customer premise equipment. Capabilities include automatic B-channel loopback, 40-kHz tone generation, a dual-call BERT feature and an enhanced D-channel Packet which supports CUG, RPOA and reverse charges. CT-100: $2,795 with 2B1Q U Interface. Tektronix, (800) 426-2200.
Hand-Held ISDN Analyzers
Test, Analyze Networks
The Models 815/830e ISDN Network Analyzers perform tests and provide traffic analysis with detailed protocol decodes and statistics. The 815 enables ISDN PRI simulation/monitoring over TI interfaces and setup of 23 separate calls with similar profiles. The 830e provides ISDN PRI and BRI simulation and monitoring over E1 and S/T interfaces, respectively. It supplies TE and NT monitor/simulation capabilities and performs voice, data and BERT tests. The 830e supports several implementations, including National ISDN, ATT 5ESS, Northern Telecom, ETSI and ITU-T. 815: $4,195; 830e; $8,950. Ameritec, (818) 915-5441.
Portable ISDN Analyzer Houses
Up to Three Interface Modules
The CoBRA ISDN BRI and PRI Analyzer is a portable unit that connects to an S/T or U interface, sets up or receives calls, and displays the protocol messages that occur between the network and the subscriber. A Basic Rate module features an S/T interface and a U interface which uses 2B1Q line coding. The Primary Rate module is available in a North American T1 or CCITT (ITU) E1 format. Standards supported include American National 1 and 2, Nortel DMS and AT&T 5ESS. $7,500. Consultronics, (800) 227-3345.
Copyright 1996 Nelson Publishing Inc.
August 1996
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