Near-End Crosstalk (NEXT) is a measure of what?

Near-End Crosstalk (NEXT) specifically measures the unwanted coupling of signals between pairs of wires in a cable at the near end, which is where the signals are transmitted and received. When a signal is sent down one pair of wires, some of that signal can unintentionally couple into an adjacent pair. This unwanted coupling can lead to interference and signal degradation for the receiver on the adjacent pair, negatively affecting the overall performance and reliability of the communication system.

Understanding NEXT is crucial because it highlights the importance of maintaining signal integrity within twisted pair cabling used in networking and telecommunications. The ability to accurately measure and mitigate NEXT is fundamental in designing high-quality cabling systems to ensure minimal interference, especially in high-speed data transmission environments.

The other options relate to different phenomena that affect transmission quality but do not specifically define Near-End Crosstalk. For instance, signal degradation due to distance refers to attenuation, which is not directly related to crosstalk. Total signal loss in a cable encompasses more than just crosstalk and includes factors such as attenuation and insertion loss. Interference from external sources involves external electromagnetic interference (EMI) rather than the internal coupling between pairs that NEXT specifically addresses.