A client device in a distributed system includes a timer for timing a request time duration substantially including a period of time that the client device is waiting for results to be received via a network from a server in response to a request sent by the client device. A processor of the client device compares the request time duration with a dynamically generated request time threshold, and automatically controls a network interface to issue one or more alert messages to a network operation center (NOC) via the network when the request time duration is greater than the request time threshold. The request time threshold is dynamically calculated according to historic request time durations timed by the timer for a plurality of previous requests sent by the client device.