Which category doubles the number of twisted pairs to four for up to 1 Gbps over 100 meters?

• A. Cat4
• B. Cat5
• C. Cat5e
• D. Cat6

Answer: (B)

The main idea is that to achieve 1 Gbps over copper up to 100 meters, you need four twisted pairs in use, since gigabit Ethernet (1000BASE-T) transmits on all four pairs in parallel. The category designed to reliably support this up to 100 meters is Cat5e. It tightened performance specs to reduce crosstalk and other impairments, enabling stable 1 Gbps operation over the common 100-meter Ethernet link. Earlier Cat5 didn’t guarantee robust gigabit performance, and Cat4 is associated with older 100 Mbps implementations rather than Gigabit Ethernet. Cat6 can also carry 1 Gbps and higher (even up to 10 Gbps for shorter runs), but the standard choice linked to enabling four-pair gigabit operation at 100 meters is Cat5e.