CompTIA Network+ Practice Test

Why is maintaining cable twists important in preventing crosstalk?

1. It increases the cable length

2. It enhances signal strength

3. It helps avoid crosstalk

4. It allows for easier installation

The correct answer is: It helps avoid crosstalk

Maintaining cable twists is crucial in preventing crosstalk because the twisting of the pairs in a twisted pair cable helps to cancel out electromagnetic interference from external sources and reduces the coupling between the pairs themselves. This design minimizes the potential for signals from one pair of wires to interfere with signals on another pair, which is a phenomenon known as crosstalk. The twisting creates a balanced impedance throughout the length of the cable, ensuring that both wires in each twisted pair are subjected to the same environmental conditions. This geometry plays a vital role in the performance of the cable by keeping the electromagnetic fields of adjacent pairs closely coupled with each other and equally influenced by external interference. As a result, any interference affects all pairs similarly, thereby balancing out and significantly reducing the likelihood of crosstalk. This characteristic is fundamental in network cables such as CAT5e, CAT6, and CAT6a, which are designed to support high-speed data transmission while minimizing interference and maintaining signal integrity. Hence, maintaining cable twists is a key factor in preventing crosstalk and ensuring reliable network performance.