> The reason I ask is that I often push the limits of current gigabit ethernet distances and have found that actual limits are much shorter than theoretical lim

> The reason I ask is that I often push the limits of current gigabit ethernet distances and have found that actual limits are much shorter than theoretical limits Get a cable tester and see what the cable type/qualtiy and signal characteristics are. Or if you're near some other equipment that is high-EM (where shielding may be needed). There is nothing theoretical about the official numbers with a quality install: * https://en.wikipedia.org/wiki/Ethernet_over_twisted_pair#Variants https://en.wikipedia.org/wiki/Ethernet_over_twisted_pair#Var... In the ISO/IEC structural cabling standard the length is strictly informative, and the length of a cable/run doesn't matter as long as the signal characteristics are good: you can have a 130m run and a tester will not pass-fail based on the length, but on the signal quality: * https://www.youtube.com/watch?v=kNa_IdfivKs&t=12m32s https://www.youtube.com/watch?v=kNa_IdfivKs&t=12m32s