Patrick McLaughlin
Cabling-system manufacturer IBM Global Services (Research Triangle Park, NC) and test-equipment maker Microtest (Phoenix, AZ) have formed a partnership whereby Microtest will be the sole supplier of test adapters for the twisted-pair IBM cabling systems designed to meet the forthcoming Category 6 and Category 7 cabling standards.
IBM`s Advanced Connectivity System (ACS) Silver product line is its Category 6 system, and its ACS Gold product line is the Category 7 system. IBM also offers an ACS Bronze line, which meets the current Category 5 and proposed Category 5E specifications of the Telecommunications Industry Association (TIA--Arlington, VA).
"The testing capability for the Gold and Silver product lines, which is available only through Microtest, includes specific test cords and test limits," says David Coffin, vice president and general manager of network test and measurement at Microtest. The test limits for the ACS Silver system are more stringent than the Category 6 limits currently proposed by the TIA, Coffin adds, explaining that the limits reflect standards being developed by the International Organization for Standardization and International Electrotechnical Commission (iso/ iec--Geneva) in addition to those under development within the TIA. He adds that the IBM cabling systems are deployed worldwide.
As a result of the partnership, Microtest now offers three new test-capability choices for the OMNIScanner. The IBM Gold test capability lists for $139; the IBM Silver capability lists for $129; and a package containing all the capabilities lists for $499. Purchasers of these packages will receive test cords for the appropriate systems, as well as a software release to load into the OMNIScanner to allow the unit to test the systems. The test-capability packages are available through all of Microtest`s distribution channels and directly from the company through its Website.
The issue of vendor-specific tester cords has come to the industry`s forefront within the past few months, especially with the introduction of cabling systems designed to meet as-yet-unratified standards. Several manufacturers claim that their systems meet proposed Category 6 link and channel requirements, but those systems achieve the proposed performance characteristics only when a single vendor`s products are used. Other manufacturers promise proposed Category 6 performance only when specific partner-vendors` products are used. In short, most proposed Category 6 systems currently on the market are not constructed in the spirit of "open" cabling systems upon which the tia/eia-568a standard is based.
Because the proposed Category 6 standard specifies such high-performing systems, manufacturers have emerged from their R&D labs with cable and, more significantly, connecting hardware that are tuned to one another to achieve necessary performance. The mated modular plug-and-jack combination has come under particular scrutiny, as manufacturers have engineered the two components to work together to cancel crosstalk. Using incompatible crosstalk-cancellation technologies from different plug-and-jack makers can put an entire system at risk of not meeting the proposed Category 6 specifications, which is why the vendor-specific testing cords have become crucial. To verify that a system performs to the manufacturer`s claims, an installer or end user must use a test cord from that manufacturer to avoid the potential for the aforementioned crosstalk-cancellation anomaly.
IBM`s ACS Silver line includes cable and connecting hardware in unshielded and shielded constructions. All products in the line are backward-compatible with Category 5 and Category 5E systems, IBM says.
The Category 7/Class F standard, currently under development by the iso/iec, may specify an 8-pin modular (commonly called RJ-45) connector interface or a non-8-pin-modular connector interface. The ACS Gold line includes a non-8-pin-modular interface, called the MiniC Gold. The company says this connector, along with the improved balance and individual pair screening in the ACS Gold system, provides a channel attenuation-to-crosstalk ratio that exceeds the currently proposed Category 7/Class F level of 46.9 decibels at 100 megahertz and 20 dB at Category 7/Class F`s maximum frequency of 600 MHz.
"We`re very pleased to be able to have reached this agreement with IBM," says Microtest`s Coffin. Mark Johnston, Microtest`s director of technology development, adds that his company is currently the only tester maker to support Category 7 testing.