Which of the following is a commonly used key performance indicator (KPI) in network monitoring?

Latency is a commonly used key performance indicator (KPI) in network monitoring because it measures the time it takes for data to travel from the source to the destination. This metric is crucial for assessing the responsiveness of a network; lower latency typically indicates a faster and more efficient network experience. High latency can lead to delays, making applications less responsive, which is particularly critical for real-time services such as video conferencing, online gaming, and VoIP communications.

In contrast, while bandwidth saturation and hardware utilization are also important aspects of network performance, they target different dimensions of network health. Bandwidth saturation refers to whether the network can handle the amount of data being transmitted without causing slowdowns, while hardware utilization often focuses on the performance of individual devices rather than the overall network experience. Signal jitter, on the other hand, measures variations in packet arrival times, affecting quality over time but not encapsulating the overall latency experienced by users. Thus, latency stands out as a direct indicator of the user experience, making it a central KPI in network monitoring.