Abstract: Techniques are disclosed for compensating for crosstalk using adaptation of data signals transmitted over respective channels of a communication network. In one example, a method comprises the following steps. Data is transmitted to a communication network device via a communication line during a sequence of periods. For each period of the sequence of periods, a separate value of a measure of crosstalk that was measured at the communication network device is received, each value being an average of measurements at the device of measures of crosstalk for a plurality of communication network signal subcarriers. For each individual signal subcarrier of the plurality, a matrix is updated based on the received values, the matrix being configured to precode data transmissions to the communication network device over the individual signal subcarrier. The communication network may be a DSL system, the signal subcarriers may be DSL tones, and the measure of crosstalk may be a SINR value.

Abstract: A method and apparatus for grooming traffic demands according to mileage based tariffs. An Integer Linear Program (ILP) that captures the traffic grooming problem is defined, and such a linear program can in principle be solved by conventional linear program application systems which are fully familiar to those of ordinary skill in the art. However, the time required to solve such an ILP is fairly large, even for the moderately sized networks we are interested in. That is, there are many possible routes to consider, and hence many integer variables in the ILP. Therefore, further in accordance with the principles of the present invention, the ILP is advantageously run on the Delaunay Triangulation of the network rather than on the completely connected network graph.

Abstract: A method includes receiving a request for admission of a new communications session to a data network. The requested admission is such that the new communications session is granted a first set of one or more bandwidth usages of a resource of the network in response to being admitted. Each of one or more admitted communications sessions concurrently has a granted set of one or more bandwidth usages of the resource. The method includes admitting the new communications session to the data network in response to a sum over each set of the largest bandwidth usage of the resource in the each set being larger than an effective input bandwidth of the resource. Each admitted communications session is able to access a bandwidth of the resource up to any of the one or more bandwidth usages in its own one of the sets.

Abstract: Techniques and systems for design of optical switch arrays so as to minimize power requirements are described. A design system includes a computer system hosting a design program. The design program receives parameters for the switch array, including a number N of outputs required, and either a maximum number L of stages allowed or maximum and average power requirements allowed. If power requirements are used as parameters, the design program uses N and the power requirements to compute the value of L. The design program then constructs a minimum power sequence of L switches or N switches, whichever is less. If N is less than L+1, N outputs are present and the array is complete. If N is greater than L+1, the design program then adds switches one at a time to the minimum power switch path of the array, until the array provides N outputs.

Abstract: Techniques and systems for control of optical switching arrays are described. A switch array controller according to an aspect of the present invention operates so as to achieve reduced power consumption and maintain crosstalk within acceptable limits. Various rules are applied in order to insure that the desired criteria are met. In order to reduce transient effects, switching from one output to another is accomplished in a sequence chosen to maximize the number of transitions occurring in those portions of the array not carrying a signal, and to minimize the number of transitions that occur in portions of the array carrying the signal. Transitions are made in the portion of the array to which the signal will be directed, then a switch is transitioned between the old and new signal paths, and finally further transitions are made in the portion of the array within which the signal was previously directed.

Abstract: Techniques and systems for control of optical switching arrays are described. A switch array controller according to an aspect of the present invention operates so as to achieve reduced power consumption and maintain crosstalk within acceptable limits. Various rules are applied in order to insure that the desired criteria are met. In order to reduce transient effects, switching from one output to another is accomplished in a sequence chosen to maximize the number of transitions occurring in those portions of the array not carrying a signal, and to minimize the number of transitions that occur in portions of the array carrying the signal. Transitions are made in the portion of the array to which the signal will be directed, then a switch is transitioned between the old and new signal paths, and finally further transitions are made in the portion of the array within which the signal was previously directed.

Abstract: Techniques and systems for assigning resource chains for transmission of a communication signal from an origination point via a node or a plurality of nodes to a termination point are described. Separate determinations of minimum costs of transmitting the communication signal from the origination point to the node and from the node to the termination point on each of a plurality of channels are made. Potential channels corresponding to such minimum costs are identified. The separate minimum costs are combined and a plurality of cumulative minimum costs of transmitting the communication signal from the origination point to the termination point are determined. A lowest cumulative minimum cost and corresponding selected channels and nodal actions from the origination point to the node and from the node to the termination point are identified. The costs of regeneration and wavelength conversion resources consistent with the channels may also be identified.