near-end crosstalk loss margin over a category 5e channel. Category 7 may offer as much as 1 GHz over twisted-pair cabling and thereby enable broadband video (with an upper frequency requirement of 862 MHz) operate over class F cabling with concurrent connections to other networking applications. Category 7 cables include individually screened twisted-pairs and an overall shield. Pending category 7 specifications require connectors to provide at least 60 dB of crosstalk isolation between all pairs at 600 MHz. Potential adopters of 100 or 1000 Mbps Ethernet should carefully examine their existing cabling to determine the necessary adjustments and require that the supplier certify that what is in place conforms to the specification in question. When it comes to EIA/TIA 568, every inch of cable plant-from the network adapter in the workstation to the wiring closet, and including punch-down blocks, patch cords and Packet-switched Networks panels-must adhere to the standards. Customers that are not certain about how their cable plant conforms to EIA/TIA 568a should test it, using a cable tester from a company such as Tektronix, Fluke, or Scope. Without an accurate reading on conformance, a manager cannot make an informed decision about what 100 or 1000 Mbps solution will work in his or her environment. When conducting a test, technical personnel (or subcontractors) should test all pairs. The reason is that if the plant turns out to conform only to Category 3 cable, all four pairs that make up a UTP bundle will have to be used to support 100VG or 100Base-T4 connections. Category 3 cable will not support 1000 Mbps Ethernet. Fast Ethernet In 1994, the Fast Ethernet Alliance completed a wiring specification that provides end users with interoperable 100 Mbps Ethernet products that can exist in a variety of cable plant environments. The completed specification, which includes three specifications, defines how 100Mbps Ethernet should run over Category 3, 4, and 5 UTP and over fiber optic cable. The three specifications for 