A link includes the cabling elements--cable and termination hardware--of the horizontal and backbone subsystems up to, but not including, the equipment cords. Transmission testing of 8-pin plugs and jacks is performed with the connectors in a mated state, so a link measurement includes the plug on the end of the equipment cord that is mated with the jack on the termination hardware but not the cord or plug used to connect the equipment cable to the network equipment.
A channel includes the same cabling elements as a link, as well as the equipment cord, but not the plug used to attach the equipment cord to the network equipment.
ISO-9000
The International Standards Organization is creating quality-assurance and certification programs in an attempt to set standards that will be globally accepted. Companies interested in doing business on a worldwide scale are finding conformance to ISO-9000 a requirement. ISO-9000 is a series of five standards, with ISO-9001, 9002 and 9003 detailing specific levels of quality. ISO-9001, for example, covers a manufacturer`s entire operation from design and development, through production, to product qualification and improvement.
The ISO does not test products as do third-party approval agencies, but it sets standards to verify that a manufacturer is following the quality system it has established. The idea behind ISO-9000 is that a manufacturer following specific quality guidelines will consistently produce higher quality, more reliable products.
Does this mean that a patch cord constructed by a manufacturer that is ISO-9001-certified is a verified Category 5 patch cord if it is constructed of cable and 8-pin plugs that are Category 5-verified? No, this means that a reputable manufacturer used quality materials to produce a patch cable.
Donna Ballast is a communications analyst at the University of Texas at Austin and a BICSI RCDD. Questions can be sent to her at Cabling Installation & Maintenance or at PO Drawer 7580, University of Texas, Austin, TX 78713. Phone (512) 471-0112, fax (512) 471-8883. Internet ad