What does 'Category' specify in copper cabling?

• A. The color code of wires
• B. The physical size of connectors
• C. The age of the installation
• D. The performance specification including frequency range and crosstalk/attenuation characteristics

Answer: (D)

Category defines the transmission performance level of copper cabling. It sets the electrical specifications the system must meet, including the maximum frequency the cable is tested for and how it handles interference, such as crosstalk, return loss, and attenuation. In other words, higher categories require higher bandwidth and stricter control of signal degradation, enabling faster data rates. It doesn’t specify wire color, connector size, or installation age. For example, higher categories support higher frequency ranges (Cat5e around 100 MHz, Cat6 up to about 250 MHz, Cat6a up to about 500 MHz), reflecting better performance requirements.