Lucent Technologies Inc.

Agere Systems Guardian Corp.

Sharad Ramanathan

Paul S Westbrook

Benjamin John Eggleton

Arturo Hale

Jon W Engelberth

Steven Herbert Simon

Glen Robert Kowach

Anindya Basu

Ashish Ahuja

Alvin Lai Lin

Raissa M D'Souza

Duncan Temple Lang

A method and apparatus for network routing in packet-based networks which advantageously takes traffic conditions into account dynamically in determining the 'best route' for routing a packet to its intended destination. Illustratively, a potential function is employed whereby hypothetical electrostatic potential values are calculated at each node or link of a network, and the packets are routed in accordance with these potential function values (e.g., in the direction of the lowest neighboring value). The potential function values may be advantageously calculated based on queue lengths at the various nodes (or links) in combination with a minimum-cost distance calculated to the packet's intended destination.

Method and apparatus for performing network routing based on queue lengths

Wireless devices within an ad-hoc wireless network adaptively set their transmission power levels based on locally available information. Initially, each such wireless device sets its transmission power level to a relatively low level, and gradually increases its power level up to a predetermined maximum transmission power level. As the transmission power increases, the wireless device is able to incrementally connect with additional wireless devices located at increasing distances from the wireless device. As the wireless device connects with these additional wireless devices, it checks a connectivity constraint. When the connectivity constraint is satisfied, the wireless device stops increasing its power and operates at its current power level. In one embodiment, the connectivity constraint is a geometric connectivity constraint based on the angular distribution of wireless device connections. When a wireless device detects a change in the network topology, it repeats the power setting steps in order to adapt to the changed topology.

Adaptive power level setting in an ad-hoc wireless network

In accordance with the invention, an optical waveguide comprising a longitudinally extending core housing an optical grating and a cladding layer peripherally surrounding the core, is provided with an outer surface of the cladding layer having one or more perturbations. Each perturbation has a height with respect to the core that varies by at least 0.1 times a Bragg wavelength of the grating over the surface of the perturbation and covers an extent of the outer surface whose linear dimensions are less than 1 cm. The perturbations suppress cladding mode spectra and reduce short wavelength cladding mode loss.

Optical waveguide gratings having roughened cladding for reduced short wavelength cladding mode loss

Growing community of inventors

Springfield, NJ, United States of America

Sharad Ramanathan