Abstract: The present invention provides methods for identifying and tracking data packets across a network. Specifically, network monitoring devices are configured to identify particular data packets or traffic flows at different points in a network by conversation fingerprinting. Conversation fingerprinting involves creating a unique identifier based on an invariant portion of one or more data packets in a traffic flow. An equivalency test is then performed between two identifiers from different monitoring devices to determine if the same data packet is received at two or more network monitoring devices. In order to reduce the probability of mismatches, additional heuristics may be applied based on additional attributes of the data packet or conversation. If a match occurs, then the timestamps of the two identifiers are compared to determine the point-to-point network transit latency between the two network monitoring devices.

Abstract: The present invention provides a framework for metering, monitoring, measuring, analyzing and reporting on network traffic data. The framework of the present invention is comprised of multiple synchronized components that each contribute highly specialized functionality to the framework as a whole. In certain configurations, the present invention includes two types of metering/measuring components, referred to as Instrumentation Access Points (IAPs). The first metering/measuring component is a terminal IAP, referred to as Node Workstation and Node Server. The second metering/measuring component is an edge IAP, referred to as Probe. Probe monitors all traffic that traverses the network segment upon which it is installed, while Node is limited to the traffic specific to the particular host (i.e., workstation or server). The IAPs communicate their data to monitoring, analysis, and reporting software modules that rely upon and reside in another component referred to as Diagnostic Server.