Abstract: A technique for ensuring that a node that carries high-priority protocol data units and low-priority protocol data units is properly configured to accord the high-level protocol data units priority treatment is described. In accordance with the illustrative embodiment, two streams of protocol data units are transmitted through a node to be tested. One stream comprises high-priority protocol data units, and the second stream comprises low-priority protocol data units. The processing capabilities of the node are then burdened by increasing the frequency of protocol data units transmitted to it, so that the node is compelled to treat the two streams differently, if, in fact, it is properly configured to treat them differently. If the node treats the two streams differently and accords the high-priority stream higher priority, then the node is properly configured. Otherwise, the node is re-configured to accord the high-priority stream higher priority.

Abstract: The system and method send test packets into a network between a plurality of source and destination nodes. Each source node is also a destination node. The test packet contains an additional field (e.g., a field of particular interest to an application or user) that is subject to being modified as the test packet traverses the network (e.g., a DSCP marking). A determination is made if the additional field has changed; if so, the network node that changed the additional field is identified and displayed to a user in a matrix display of the source nodes and destination nodes. This allows a user to identify situations where changes in the additional field may indicate that the test packet is being routed in the network at a priority that is outside of a Service Level Agreement.

Abstract: A packet analyzer(s) gets multiple packets, typically of a communication between communication devices. The multiple packets use the same protocol and contain one or more protocol headers with individual field(s) that contain data. The packets are organized into an array of packets. Each packet is a row in the array of packets. Each column in the array is comprised of the same field in each packet in the array of packets. The data in the fields in the column are then compressed into a compression packet.

Abstract: A network monitor gets a (layer 7) media path bill of materials for a communication between two communication devices. The network monitor also gets a (layer 7) signaling path bill of materials. The media path bill of materials and the signaling path bill of materials comprise a plurality of items that are involved in the communication (e.g. hardware, software, links). The media path bill of materials and the signaling path bill of materials comprise a communication path bill of materials. The network monitor sends at least one configuration packet to a plurality of network analyzers to monitor packets that contain a status of the communication in relation one or more items in the communication path bill of materials. The status of the communication is output and displayed in relation to the items in the communication path bill of materials.

Abstract: A network monitor gets a bill of materials for a communication across a network where different communication paths may be established. A bill of materials is a list of hardware/software components that are used to establish and maintain the communication. A request to generate a test communication between the same devices involved in the communication is received. A request to sample and send samples of test data is sent to a network analyzer. The test communication is established. A bill of materials for the test communication is determined. The bill of materials for the communication is compared to the bill of materials for the test communication. Test data is sent on the test communication. The sent test data is analyzed in relation to the sent samples of the test data and the compared bills of materials.

Abstract: An apparatus and method are disclosed that enable a first telecommunications endpoint to ensure that a second endpoint is receiving the first endpoint's packet stream transmissions with a satisfactory waveform quality. When the second endpoint receives the packet stream, it decodes the media waveform from the stream, encodes the waveform back into a second packet stream, and transmits some or all of the packets in the second stream back to the first endpoint. The first endpoint then decodes the received waveform in the second stream and compares it to the original waveform transmitted to the second endpoint. Based on the comparison, the first endpoint adjusts the value of a quality indication, and provides the quality indication to its user and to the second endpoint. Advantageously, the user at the second endpoint is able to determine whether the received waveform is, in fact, close enough to the waveform that the first endpoint's user intended to be received and understood.

Abstract: Systems and methods are presented for partitioning end-to-end performance effects using network tomography. In one embodiment, a method for partitioning end-to-end performance effects within a network is presented. The method includes determining a network topology between at least two test points, obtaining an unrelated approximation of edge effects between the test points, measuring end-to-end performance data between the test points corresponding to a target application, regularizing an estimate of edge effects for the target application using the unrelated approximation of edge effects, and computing the estimate of edge effects for the target application to partition the end-to-end effects.

Abstract: A network analyzer gets configuration information, usually in the form of a configuration packet sent from a network monitor. The configuration information comprises a second device network address and a third device network address. The second device network address is that of the network monitor and the third device network address is that of a communication device that is to be monitored. When the network analyzer sees packets from the monitored communication device, it can send the results to the network monitor for analysis without having to be configured with a unique network address. The network analyzer sends an original packet using the network address of the communication device as the source address and using the network address of the network monitor as the destination address.

Abstract: A method is disclosed for adaptively and intelligently partitioning traffic among a plurality of communications channels, without injecting probe traffic into any of the channels. In accordance with the illustrative embodiment, a source node transmits traffic to a receiving node via K communications channels in accordance with partition coefficients ?1, . . . , ?K, and the source node receives information regarding the quality of service (QoS) provided by each of the communications channels. The source node adjusts the values of the partition coefficients ?1, . . . , ?K adaptively based on: the current channel QoS information, prior channel QoS information, the prior values of ?1, . . . , ?K, and a measure of channel independence for one or more pairs of communications channels.

Abstract: A technique for ensuring that a node that carries high-priority protocol data units and low-priority protocol data units is properly configured to accord the high-level protocol data units priority treatment is described. In accordance with the illustrative embodiment, two streams of protocol data units are transmitted through a node to be tested. One stream comprises high-priority protocol data units, and the second stream comprises low-priority protocol data units. The processing capabilities of the node are then burdened by increasing the frequency of protocol data units transmitted to it, so that the node is compelled to treat the two streams differently, if, in fact, it is properly configured to treat them differently. If the node treats the two streams differently and accords the high-priority stream higher priority, then the node is properly configured. Otherwise, the node is re-configured to accord the high-priority stream higher priority.

Abstract: A technique is disclosed that attempts to improve the evaluation of a network path's signal quality, as well as the selection of a network path for transmission purposes, without some of the costs and disadvantages of doing so in the prior art. In accordance with the illustrative embodiment, a node with access to the packet network, such as a VoIP telephone endpoint, evaluates the quality of service that is associated with each of multiple network paths. The evaluation process is iterative, in which the number of candidate paths is successively reduced from one iteration of the technique to the next. The multiple paths that remain as candidates in any given iteration are evaluated concurrently and at an evaluation bit rate that i) is less than the full transmission rate of the real-time traffic (VoIP) packets to be sent and ii) varies as a function of the number of candidate paths remaining under consideration.

Abstract: Node merging methods and apparatus are disclosed for generating simplified representations of network topology. A first topology representative of a given network is determined, and at least one pair of nodes of the first topology is merged into a single node based on measures associated with respective edges connecting the nodes of the node pair to at least one neighbor node common to that pair. The merging step is repeated for one or more additional pairs of nodes to produce a reduced network topology meeting one or more desired criteria, and a visualization or other representation of the reduced network topology is generated.

Abstract: A technique is discloses that enables a first telecommunications terminal, wireless or otherwise, to report to its user whether a second, wireless telecommunications terminal is receiving the first terminal's packet stream transmissions at a satisfactory quality level. The second terminal receives the packet stream that conveys the media waveform transmitted by the first terminal. The media waveform can be that of the speech signal of the first terminal's user. The second terminal measures a trait of the received signal and encodes the measurement data into the packet stream that the second terminal is already transmitting to the first terminal. The first terminal then decodes the measurement data from the received second stream and presents, to its user, a quality indication that is based on the measurement data. In doing so, the first terminal provides its user with a better idea of whether the second terminal has reliably received the user's communication.

Abstract: A method is disclosed that enables a participant in a conference call to monitor, as he is speaking, whether his speech is getting through to the other participants. A teleconference bridge receives audio signals from a group of telecommunications endpoints that are involved in a conference call. The bridge generates audio signals to be transmitted, which are based on one or more of the received audio signals. During the ongoing process of minimizing the presence of acoustic echo, the bridge might exclude one or more of the received audio signals from the transmitted audio signals. When this occurs, particularly when an active talker is being excluded, the bridge transmits an indication to one or more of the endpoints as part of one of the transmitted audio signals. The indication can be audible such as a tone or a voice, visual such as a flashing light, or tactile such as vibration.

Abstract: A system for monitoring traffic on a network first discovers the network so as to map the various devices and links in the network. Statistics are then gathered from various points in the network relating to quality of service, and especially loads on the network devices. Synthetic calls are generated at selected points of the network while monitoring the network. This data is then stored and displayed in a manner that is easy for the operator to analyze, with more detailed displays being available through the use of a mouse or keystrokes.

Abstract: A method and apparatus are disclosed for redirecting traffic associated with an application so that the traffic advantageously traverses (or “hairpins”) through an application-layer gateway. Because the present invention advantageously redirects traffic without any participation by routers, no changes to or replacement of routers in a network is required. The illustrative embodiment is disclosed in the context of Internet telephony, but is also applicable to other kinds of applications and types of communication (e.g., Internet Protocol Television [IPTV], instant messaging [IM], videoconferencing, etc.

Abstract: One or more network elements that modify type of service values in a network are detected by sending route tracing messages having increasing time-to-live values and a designated type of service value from a first network element to a second network element. Type of service values are monitored in respective time exceeded messages received from respective network elements on a given network path between the first network element and the second network element responsive to the route tracing messages. At least a particular one of the network elements on the given network path that has made a modification in type of service value relative to the designated type of service value is identified, based on the monitored type of service values in the respective time exceeded messages.

Abstract: Network topology information is determined in a network-based communication system by generating communications between, for example, selected pairs of endpoint devices each associated with a network. A given one of the communications is sent from a first one of the endpoint devices to a second one of the endpoint devices and returned from the second endpoint device to the first endpoint device. Information contained in the communication as received at the first endpoint device from the second endpoint device is processed to determine network topology information characterizing at least a portion of the network.

Abstract: An IP telephone or other endpoint device in a network is configured to support a reporting mode of operation that may be entered, for example, responsive to user entry of a report command via a user interface of the endpoint device. In one aspect, the endpoint device stores call information in one or more buffers. Responsive to an instruction to enter a reporting mode, the endpoint device sends contents of the buffer(s) to a report server over the network. The endpoint device may reinitialize the buffer(s) responsive to an instruction to leave the reporting mode.

Abstract: Techniques for determining a problem location or otherwise characterizing a network comprising a plurality of processing elements, including at least one processing element associated with performance of a packet encapsulation operation of an encapsulation protocol. The packet encapsulation operation is performed on a test packet to generate an encapsulated packet, the test packet having a time to live (TTL) value and an identifier. In conjunction with performance of the packet encapsulation operation, the TTL value and the identifier of the test packet are copied to a header of the encapsulated packet. The encapsulated packet is transmitted, and a determination is made as to whether a reply packet has been received responsive to transmission of the encapsulated packet. The reply packet, if any, is processed to obtain information utilizable in determining the problem location or otherwise characterizing the network.