Abstract: The test packet sequencer according to the present invention, is configured to generate one or more sequences of packets and subsequently place these one or more sequences of packets onto a communication network. The test packet sequencer is further configured to measure timings associated with the one or more sequences of packets. For example, the test packet sequencer can be configured to measure the departure and/or receipt times of one or more sequences of packets. In order to overcome inherent delays or inaccuracies relating to the functionality of one or more components along the network path, the test packet sequencer is configured to pre-activate at least a portion of the network path prior to placement of the one or more sequences of packets on the communication network.

Abstract: A system for identifying problems in networks receives test data which may include statistical information regarding packet loss on a path. The system creates a signature from the test data and compares the signature to example signatures corresponding to various network conditions. The system identifies one or more of the example signatures which match the test signature. The system may comprise an expert system which applies rules to identify an example signature that the test signature best matches.

Abstract: The present invention provides a method and apparatus for determining the service quality performance of a real-time application, for example VoIP, video over IP or IPTV, operating over a path defined in a packet-based network. The present invention performs active probing of a path of the packet-based network by transmitting one or more sequences of packets along the path.

Abstract: The present invention provides a method an apparatus for adaptively refining the sampling within an IP network performance monitoring and diagnosis framework. This ability to adaptively adjust the resolution of the sampling can enable variable accuracy and detail in the related IP network analysis. The sampling resolution can be defined as, for example, the load on the network in terms of the rate of packet transmission, the statistical variance thereof and the complexity of the sampling procedure. Each sampling and analysis procedure determines one or more network parameters referred to as critical indicators. Decisions for subsequent samplings and actions are made based on the determination of these critical indicators. As such various evaluation activity levels are defined by conditions that can be checked for and detected within the context of that activity level.