Abstract: A distributed network monitoring system includes a central monitoring device configured to fetch network traffic information from one or more remote monitoring devices in response to receiving a notification from the remote monitoring devices that the network traffic information is available, the remote monitoring devices being communicatively coupled to the central monitoring device. The network traffic information is associated with a timestamp which indicates a time period at which the network traffic information was collected by the remote monitoring devices. The central monitoring device further synchronizes the network traffic information from the remote monitoring devices by comparing the timestamp of the network traffic information with a system timestamp provided by a system clock or network time protocol (NTP) server. The network traffic information is identified as unavailable if the timestamp cannot be located when compared to the system timestamp.