1 Gb/s vs. 10 Gb/s

10 Gigabit Ethernet creates new issues which were not relevant at speeds of 1 GBE and below! This is due to two major effects that make the difference between 1 and 10 Gb/s:

	Lower Signal Levels: Due to its complex modulation encoding (PAM 16) 10GBASE-T operates with significantly lower signal levels per symbol than slower protocols. While 1000BASE-T sends with an initial symbol amplitude of 0.5 V 10GBASE-T only uses 0.13 V – which is further attenuated over the length of the cable. Such lower level signals are more likely to be interfered with by background noise!

	Higher Self-Radiation: Every transmitting line also radiates by itself. And since 10 Gb/s uses a much higher transmitting power (e.g. power consumption per 10G port is upto 15 W compared to 0.5 W for 1G) it radiates much more – specifically in the relevant bandwidth from 250 to 500 MHz (see chart)! 10 Gb/s suddenly impacts itself because neighboring cables interfere with each other, an effect called “Alien Crosstalk” or ANEXT.