Arlyn S. Powell, Jr.
Anixter enhances its Levels program, while Graybar introduces VIP 2000 as better-than-Cat 6.
Spokespeople for Anixter Inc. (Skokie, IL) like to point out that before there were categories, there were levels. And, in fact, it's true that this large international distributor launched the first version of its Levels verification program before the Telecommunications Industry Association (TIA-Arlington, VA) first developed the EIA/TIA-568 commercial building wiring standard.
The TIA expanded the basic standard with additional specifications for unshielded twisted-pair (UTP) cables and connecting hardware with two supplementary telecommunications systems bulletins, TSB-36 and TSB-40. These documents introduced the TIA Category system, so named to distinguish them from Anixter's Levels designations.
Levels or Categories?
There was some confusion early on when many in the cabling industry tended to use the terms "level" and "category" interchangeably, but the misunderstanding gradually sorted itself out as the TIA's industry-wide body of wiring standards took hold and the Anixter designations gradually withered away.
During the last few years, however, the Levels program, along with several successors, has reappeared-with a vengeance. In 1997, Anixter saw the need to reintroduce a graduated verification program for cabling-system performance because the company's customers were being bombarded by claims from manufacturers that their cabling and components exceeded the Category 5 specification, then the highest-bandwidth category established by the TIA.
The TIA has continued to develop higher-performing standards, with Category 5E already approved to specify so-called "Enhanced" Category 5 systems. Category 5E retains Category 5's 100-MHz performance limit, but it adds electrical specifications that permit UTP cabling systems to carry Gigabit Ethernet and other advanced data-communications protocols. A Category 6 standard, extending usable UTP bandwidth to 200 MHz, is in draft form, and a Category 7 standard for shielded cabling systems that extends copper-cabling systems to 600 MHz is under development within the International Organiza-tion for Standardization/Interna-tional Electrotechnical Commission (ISO/IEC-Geneva, Switzerland).
An industry-wide body made up of volunteer-manned committees trying to balance competing commercial interests is likely always to trail the industry it tries to police, however, and so it is not surprising that the TIA as a standards-making body has not been able to keep pace with the technological innovations introduced by its own member companies.
Stepping into this breach has been Anixter, along with several other large national voice/data distributors. These companies have established their own cabling-system verification programs, which are similar in providing a distributor's customers with:
- Specifications defining several levels of cable-plant performance, using the same or similar electrical parameters to those included in the TIA Category specifications; these parameters, however, are extended to cover networking protocols or performance demands that exceed those published by the TIA to date;
- A procedure for testing the claims made by manufacturers about the performance of their products; testing can either be done at an in-house facility of the distributor or undertaken by an independent, third-party testing laboratory;
- Distribution of test results in the form of classification of a manufacturer's product lines to the performance levels defined by the distributor; in some cases, distributors decline to stock cabling products not living up to the performance claims made by their manufacturers;
- A procedure for retesting and requalifying stocked products periodically, to ensure manufacturers are maintaining the advertised performance levels of their product lines; and
- In some cases, guarantees or warranties that supplement those of the manufacturer, attesting to the distributor's classification levels assigned to various product lines.
The Anixter Levels program as it exists today is quite different from the enterprise the company introduced at a press conference in 1997. The full details of the program have been covered previously in this magazine (see "For More Information...," page 78), but several unreported components have recently been added to it.
Anixter extends Levels program
This May, for instance, Anixter launched the Levels XP program, which addresses one of the basic deficiencies of the TIA's generic cabling standards. This deficiency is that, although the standards specify the performance requirements that must be met by individual cabling components, as well as by those components joined together into cabling infrastructure, they do not address how this passive cabling infrastructure will actually behave when active networking equipment is attached to it.
Anixter, in cooperation with a number of major cable and component manufacturers it represents, has undertaken an extensive testing program at its new Levels Lab in Mt. Prospect, IL. The program tests network cabling systems with active data signals to determine how the passive infrastructure interacts with the active network. The result is that a manufacturer's product lines, if successfully tested, can be classified as either XP-6 or XP-7.
Pete Lockhart, Anixter's vice president of technology and product design, explains why the distributor believes such a program is important. "Existing industry specifications can be compared to manufacturing standards for automobile tires," he says. "Although the brands meet the same manufacturing requirements, you wouldn't mix Firestone and Goodyear. They would be mismatched and would ultimately damage your vehicle. Similarly, mismatched network components may comply with minimally prescribed industry standards, but were never designed to function together."
In related news, Anixter has just announced that its Levels Lab has successfully completed an engineering and management-systems audit administered by the independent, third-party verification organization, Underwriters Laboratories (UL-Melville, NY). The distributor claims its lab is the only one of its type to receive certification under the UL Performance Verification Program, which is aimed at research facilities that demonstrate advanced engineering, sound scientific practices, and superior product-testing capabilities.
According to Steve Galan, UL's coordinator of the wire and cable business sector, "UL's audit determines whether a company has a documented laboratory quality program, as well as the equipment, personnel, and procedures necessary to conduct laboratory testing on an ongoing basis. Essentially, Anixter's Levels Program is based on sound engineering principles and does exactly what it claims to do."
In the summer of 1999, Graybar (St. Louis, MO), like Anixter a major player in voice/data distribution, announced its own verification program. Labeled VIP (which stands for "Verified Independently for Performance"), the program is based on a partnership between the distributor and indepen dent, third-party testing organization Intertek Testing Services (ITS-Cortland, NY), owner of the ETL Testing Lab.
The first phase of the program, dubbed VIP 1000, was based on the TIA's Category 5E standard. It also included additional transmission characteristics designed to provide more headroom and bandwidth, so that a VIP 1000 system could comfortably carry Gigabit Ethernet-something Graybar claimed off-the-shelf Category 5E cabling systems could not do, despite the fact that the TIA specifically designed the specification to meet that criterion.
This spring, Graybar and ITS announced that initial testing on the second phase of the program, VIP 2000, had been completed. A VIP 2000 designation is meant to assure customers they are installing a cabling system with usable bandwidth to 250 MHz, the proposed upper testing limit of the TIA's draft Category 6 UTP cabling standard.
"The proposals requiring support for networking applications over cabling systems that run at up to 250 MHz are being discussed by the TIA," observes Graybar vice president Rob Bezjak. "We have developed a specification to support multiple generations of Gigabit Ethernet electronics, which will reduce the installed cost of high-speed networks for our customers."
Explaining Graybar's relationship with the ETL Lab, Bezjak adds, "We use the professional expertise of the ETL staff to conduct the testing of products, which they select at random from our inventory. ETL than determines the pass/fail status of the channels tested, and suggests corrective action if necessary."
Details of Anixter's Levels program are available on the distributor's Website at www.anixter.com. For more on Graybar's VIP program, see www.graybar.com.