Product Update: LAN 'analyzers' going beyond troubleshooting
It wasn't that long ago when testing local-area-network (LAN) cable for its physical health was deemed sufficient. Less than three years ago, in fact, one industry spokesperson proclaimed
It wasn't that long ago when testing local-area-network (LAN) cable for its physical health was deemed sufficient. Less than three years ago, in fact, one industry spokesperson proclaimed, "There are no current network applications or applications of any form that require performance beyond 100 MHz."
The exponential growth of the Internet, however, has changed everything, including the advent of high-bandwidth, high-performing copper and fiber cabling, not to mention that supersonic Category 6 specifications are no longer wishful thinking but a soon-to-be-ratified standard.
The OMNIScanner2 from Microtest claims to instantly pinpoint the cause of NEXT and return-loss failures.
"Today's high-performance cabling and stringent return-loss specifications make diagnostics more critical than ever," says Hugo Draye, marketing manager for Fluke Corp.'s (Everett, WA) media test products. With the recent version 3.0 software upgrade to its DSP-4000 cable tester, Fluke joins fellow cable-tester kingpins Wavetek Wandel Goltermann (San Diego), Agilent Technologies (Marlboro, MA), Datacom Textron (Everett, WA), and Microtest Inc. (Phoenix) in rolling out comprehensive devices that do more than just measure the basics-they analyze the entire installation (see Product Update table, page 128).
Today's LAN cable testers all handle traditional wiremap tasks-such as looking for circuit shorts, opens, crossed pairs, and incorrect pin configuration-and some like Paladin Tools' (Ashland, VA) LAN ProNavigator go further by checking for resistance and near-end crosstalk (NEXT). But for about $4,000 to $5,000, a new breed of LAN analyzers take on a do-it-all mentality, adding performance assessment and predicting potential trouble spots along the network.
While installers routinely provide LAN certification reports based on TIA/EIA/ISO requirements, it's only the first step for anyone seeking to gain a competitive advantage, because high-performance users are no longer satisfied that a network will simply work; they also want assurances from the installer that it will work well. So LAN installations are increasingly coming to mean "if you build it-and if you maintain it-they will come."
Leading manufacturers like Wavetek Wandel Goltermann are capitalizing on the "value-add" trend. LAN-checker 100 targets "high-end installers with maintenance responsibilities," says senior product marketing manager Caroline Chen. A key feature is a built-in traffic-and-error generator that simulates stressed network situations to help predict future network performance.
Microtest's S-band advanced diagnostics technology, meanwhile, is designed to help installers who use the company's OMNI-Scanner2 field tester to "instantly pinpoint the cause of NEXT or return-loss failures," says Mark Johnston, director of technology development. Microtest believes S-bands will be instrumental in helping installers save time diagnosing critical Category 6 performance and failures and other problems caused by patch-cord variations and inconsistent plug or jack terminations.
Second-generation Cat 6
Calling OMNIScanner2 "the first second-generation Category 6 field-tester on the market," Johnston says Microtest's patent-pending Adaptive Vector Cancellation technology supports full Category 6 channel testing with any plug and is "the only field tester approved to test Category 7 links." An OMNIFiber option supports both singlemode and multimode fiber testing with one adapter set. It features a one-button Autotest and simultaneous dual-wavelength measurement of two fibers.
Claiming instantaneous pinpointing of crosstalk and return-loss sources, Fluke's HDTDX (high-definition time-domain crosstalk) technology in its DSP-4000 uses fast pulse diagnostics sourced from both ends of the cable link. HDTDX "profiles" the crosstalk along the total length of the link being tested, eliminating the need to trace connections. In addition, Fluke claims that problems with connectors, cables, or patch cords can be quickly located and displayed.
The DSP-4000 also works with optional link-interface adapters to address different types of cable. "The adapters allow for upgrades when new types of cable are developed, including Category 5E and the coming Category 6," says Julie Koontz, public relations manager for Fluke Networks Div. "When used with the optional DSP-FTA410s fiber test adapter, the DSP-4000 can also certify LAN basic fiber links to TIA/EIA and ISO/IEC standards."
A built-in traffic and error generator in Wavetek Wandel Goltermann's LANchecker 100 simulates stressed network situations to help predict performance.
Agilent Technologies claims its WireScope 350 exceeds proposed requirements for Cat 6 certification; it is designed for quick hardware/software upgrades to keep pace with any other future LAN or cabling standard. Three years ago, Agilent (then Scope) set the pace with a 160-MHz test-frequency-range device, amid industry debate that testing at such a high frequency was excessive and unnecessary. But that was before Cat 5E and now the pending Cat 6. Recently, NORDX/CDT (St. Laurent, QC, Canada) evaluated the WireScope 350 on its 4800KX system, with a rated bandwidth of 300 MHz. According to Paul Kish, a senior product manager at NORDX/CDT, the WireScope 350 "gave accurate readings over the complete frequency range up to 350 MHz, in accordance with the proposed Level III accuracy specifications from the TIA. A good correlation was obtained for sensitive crosstalk and return-loss measurements, with only minor deviations attributed to test setup differences."
But Microtest's OMNIScanner goes even further, claims Johnston: "It's the only device to achieve Level IV accuracy and the only one with two independent laboratory approvals."
Datacom Textron, however, also claims its new NXT Network Text Tablet provides guaranteed measurement bandwidth well above Category 6 and up to Category 7. "NXT will offer a future interchangeable module for Category 7 and ISO Class F, xDSL, advanced network analysis, high- performance fiber testing, and more," says Colleen Ries, director of customer response and communications.
Highlighting the NXT platform is Datacom Textron's XACT module that can conduct both Category 6 twisted-pair and fiber-optic testing, while the XAMINE module transforms NXT into a network diagnostic tool for 10- and 100-Mbit/sec Ethernet networks, "identifying problems from the NIC [network interface card] to the hub and everything in between."
All Datacom Textron testers offer the company's proprietary LinkTalk technology, allowing voice communications over any twisted-pair test link for automatically locating usable wires-even if the cable has been miswired. LinkTalk includes built-in microphones, volume controls, and earphones.
Installers, meanwhile, are simply happy to have physical and performance testing capabilities in one package. Says Buddy Venne, a wide-area-network/LAN specialist at Onyx Acceptance Corp. (Foothill Ranch, CA), "The things we used to hope for and look for are now all built-in. But what I would really like to see is a tester that you can use quickly after not touching it for months."
The new breed of LAN cable analyzers are answering that request, too. Windows-based software and mass-storage multimedia cards let an installer download and store all test results-hundreds, even thousands-for future reference. As a recent Wavetek Wandel Goltermann study points out, "The bottom line for both professional cable installers and network administrators is the fact that simply testing the physical layer is no longer an adequate predictor of network performance. Whether the solution consists of portable field-testers for generating and analyzing traffic or comprehensive systems for ongoing monitoring of actual traffic, the ultimate goal is the same: to ensure that real-world network performance can consistently meet and exceed mission-critical requirements."
If your company manufactures the type of products in the table on page 128, and you wish to be included in future Product Updates, contact Steve Smith at tel: (603) 891-9139, or e-mail: firstname.lastname@example.org.