Explanation

100BASE-TX is a standard for Fast Ethernet over twisted pair cables. It provides a data transfer rate of 100 Mbps (megabits per second) over a distance of up to 100 meters (328 feet) using two pairs of unshielded twisted pair (UTP) cable. The cable typically used for this standard is Category 5 (CAT5) UTP or better.

This standard uses a technique called 4B/5B encoding, which allows 100Mbps data transfer to be transmitted over two pairs of wires, using a maximum cable length of 100 meters. The 100Mbps speed represents the maximum data transfer rate that can be achieved over the cable, and in practice, the actual data transfer rate may be lower due to network overhead and other factors.

It's worth mentioning that 100BASE-TX is a technology that is no longer in wide use, it's been replaced by faster standards such as Gigabit Ethernet (1000BASE-T) and 10-Gigabit Ethernet (10GBASE-T) which provide even higher transfer rates over similar cables.