FS518T.Manual.FINAL 5/19/00 12:55 PM Page 43
Using 1000BASE-T Gigabit Ethernet over Category 5 Cable
Overview
When using the new 1000BASE-T standard, the limitations of cable installations and the steps necessary to ensure optimum performance must be considered. The most important components in your cabling system are patch panel connections, twists of the pairs at connector transition points, the jacket around the twisted pair cable, bundling of multiple pairs on horizontal runs and punch down blocks. All of these will affect the performance of 1000BASE-T technology if not correctly implemented. The following sections are designed to act as a guide to correct cabling for 1000BASE-T.
Cabling
The 1000BASE-T product is designed to operate over Category 5 cabling, but to further enhance the operation, the cabling standards have been amended. The latest standard is Category 5e, which defines a higher level of link performance than is available with Category 5 cable.
If installing new cable, we recommend using Category 5e cable, since it costs the same as Category 5 cable. If using the existing cable, be sure to have the cable plant tested by a professional who can verify that it meets or exceeds either ANSI/EIA/TIA-568-A:1995 or ISO/IEC 11801:1995 Category 5 specifications.
Length
The maximum distance limitation between two pieces of equipment is 100 m, as per the original Ethernet specification. The end to end link is called the “channel.” TSB-67 defines the “Basic Link” which is the portion of the link that is part of the building infrastructure. This excludes patch and equipment cords. The maximum basic link length is 295 feet (90 m).