On Friday, 4-November-2005 12:36, pelibali wrote:
Hi,
I found several unofficial values, how long can be the longest RJ45 network cable. Few sites listed about 12 meters, but I saw 20 meters and also 300ft as well; later being in fact around 90 meters
End-to-end distance from an Ethernet transmitter to an Ethernet receiver cannot exceed 100 meters (328 feet). This is due to the timing of the electrical signal on the cables. Excluding patch cables, the maximum cable run cannot exceed 90 meters (295 feet). The is the cable run from the patch panel to a jack. Cross-connect jumpers (used in patch panels) and patch cables (used to connect PCs/servers/printers to jacks) should not exceed 6 meters (20 feet) in length. Total combined length for an individual connection (referred to as a "channel") should not exceed 10 meters (33 feet). The 802.3u spec for 100Base-TX recommends that patch cables for PC-to-jack connections be no longer than 3 meters (9.8 feet). However, the can be longer IF and ONLY IF the total cable distance between the PC and the switch does not exceed 100 meters. Keep in mind that all this assumes that you have solid-core cable. If you have stranded core, all bets are off. Avoid stranded-core cables if at all possible.