Exceeding this limit doesn't just result in a slightly slower connection; it can lead to , where the electrical signal weakens so much that the receiving device can no longer distinguish data from background noise. Why 100 Meters? The Physics of the Limit The 100-meter limit exists for three primary reasons:
Longer wires have more resistance , leading to larger voltage drops. This is especially critical for Power over Ethernet (PoE) , where a cable too long may not deliver enough power to run a camera or Wi-Fi access point. Environmental Variables: When 100m is Too Long
In older half-duplex Ethernet, the length was limited so that a computer at one end could detect a "collision" (two devices talking at once) before it finished sending its data. network cable length
As electricity travels through copper, it meets resistance, causing the signal to lose energy and "fade".
Physics isn't always constant. Several factors can shorten your effective cable length: Exceeding this limit doesn't just result in a
of "permanent link" (the solid copper wire hidden behind walls).
For most modern copper-based Ethernet networks, the standard maximum length for a single cable run is 100 meters (approx. 328 feet) . This distance is rarely a single continuous wire. In professional installations, it is typically divided into: This is especially critical for Power over Ethernet
(split into 5m on each end) for "patch cables" to connect your devices to the wall outlet.