What does bandwidth measure in networking?

Bandwidth in networking refers to the difference between the highest and lowest frequencies that a network signal can utilize. It essentially defines the capacity of a network connection in terms of how much data can be transmitted over a specific period of time. A greater bandwidth indicates a higher capacity for data transmission, which is crucial for efficient communication and high-speed internet connectivity. This concept is fundamental in evaluating network performance, as it directly influences the speed and volume of data that can be sent or received.

Other options do not accurately reflect the concept of bandwidth. For instance, measuring the duration a signal can last pertains more to signal integrity and timing, rather than its capacity for data transfer. Similarly, the physical distance covered by a network medium relates to the reach of a network rather than its signal capacity, while the amount of data stored on a network device concerns storage memory and not the transmission capabilities of the network itself. Hence, the correct choice clearly captures the essence of what bandwidth measures in networking.