Category 6 cable commonly referred to as cat 6 is a cable standard for gigabit ethernet and other network protocols that are backward compatible with the category 55e and category 3 cable standards compared with cat 5 and cat 5e cat 6 features more stringent specifications for crosstalk and system noise the cable standard provides performance of up to 250mhz specification 3 mtr grey utp unshielded twisted pair nbs