Avaya Inc.

Sean S B Moore

Wing Fai Lo

Paul Sprague

Howard C Reith, Iii

Ben Baten

Techniques are disclosed for selecting transmission resources in a telecommunications system that comprises different networks, where the techniques are based on the quality of the waveform of transmitted media such as audio or video signals, in contrast to the quality of service of the network that transports the media. The problem with only using quality of service to determine which resources to allocate to a call is that quality of service does not guarantee that the quality experienced by the call's participants is satisfactory just because a component network's quality of service is satisfactory. For example, the end-to-end delay experienced in a VoIP network might be satisfactory for most data transfers, but might still be inadequate to control the echo experienced by telecommunications users. The disclosed techniques evaluate the waveform quality (i.e., in terms of loudness, noise, echo, and so forth) of media that is transmitted along a path and allocate alternative resources accordingly.

Waveform quality feedback for the selection of gateways

A software and hardware system that provides for per flow guaranteed throughput and goodput for packet data flows using network transport protocols that have window-based flow control mechanisms or TCP-friendly flow control mechanisms. The system and method for guaranteed throughput of individual flows in turn enables a method for provisioning link bandwidth among multiple flows and provisioning network throughput and goodput at the granularity of individual flows. The invention also eliminates Layer 3 packet drops for a data flow using window-based flow control or TCP-friendly flow control, which in turn obviates congestion collapse and quality collapse scenarios.

System and method for per flow guaranteed throughput, multiple TCP flow bandwidth provisioning, and elimination of packet drops for transmission control protocol (TCP) and TCP-friendly protocols

It is recognized in the disclosed technique that the way impairments on a conference call are diagnosed and handled in the prior art can sometimes be as distracting as the impairments themselves. The disclosed technique attempts to address some of the disadvantages in the prior art by monitoring the signal path quality on a conference call and, based on the quality of the signals received, performing one or more actions that are intended to minimize distractions while handling the impairments. In particular, in accordance with the illustrative embodiment of the present invention, the technique performs a multi-threshold evaluation of media signals that are received at a conferencing server. If a measure of the impairment being considered exceeds a first threshold, but not a higher second threshold, then a first set of actions is taken to handle the impairment. If the measure exceeds the second threshold, then a more-extreme second set of actions is taken.

Monitoring signal path quality in a conference call

Methods and apparatus are provided for improving an admission control system using feedback control techniques based on a system performance measure. Generally, one or more performance metrics, such as system output error measurements, are fed back into the admission control system to adjust one or more system parameters and thereby improve the overall performance (e.g., reduce the error measurement). For admission control, one or more performance predictors are used to evaluate an expected quality of the call. The performance of the predictor is evaluated; and at least one of the one or more parameters is adapted based on the evaluation.

Method and apparatus for adaptive control of system parameters for admission control

Methods and systems are disclosed for scheduling one or more tasks to be performed by a resource modeled as a mathematical group. One or more tasks to be performed by a resource modeled as a mathematical group are scheduled by selecting a coset representative k of a subgroup of the mathematical group based on predefined criteria for homogenization of the one or more tasks. The one or more tasks may comprise, for example, packets and the resource may be, for example, one or more communications links in a packet network. The predefined criteria for homogenization of the one or more tasks includes, for example, a time-based or a size-based homogenization of the tasks (or both).

Method and apparatus for scheduling periodic tasks based on synthetic homogenization

Methods and apparatus are provided for measuring and evaluating access link performance in IP networks that reduce the amount of required test traffic. Performance values supported by access links in a packet network that interconnects regions of an enterprise network are evaluated by (i) obtaining a plurality of test measurements for a set of N access links; (ii) formulating a matrix equation (Ax=D), where A is an invertible matrix, such as a Hadamard matrix, x is a vector of unknown access link performance parameters and D is a vector based on the plurality of test measurements; (iii) assigning one or more numeric values to one or more unproducible equations in the matrix equation based on one or more system properties; and (iv) obtaining a performance parameter value on each directed edge for the set by applying an inverse matrix Ato each side of of the matrix equation.

Method and apparatus for link performance measurements in a packet-switched network

Methods and apparatus are provided for QoS-based admission control (QBAC). The disclosed QoS-based admission control techniques use QoS parameter measurements. An admission control request for a call on a path in a packet network is processed by obtaining performance data for the path; and predicting a performance of the call on the path using performance data for the path. In one implementation, the predicted performance is based on one or more derivatives of the performance data. Typically, the performance data includes historical performance data and is based on at least one quality of service metric.

Method and apparatus for quality-of-service-based admission control

The invention described is a system and method for efficient scheduling of periodic phenomena including a collection of methods for modeling and selecting periodic task rates, resource schedule periods, and units of measure for the task and resource periods in scheduling systems such that the systems' schedulers may be improved with respect to performance metrics such as collision avoidance, computational efficiency, and resource utilization.

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Hollis, NH, United States of America

Sean S B Moore