Nortel Networks Corporation

Rockstar Consortium US LP

Humair Raza

Robert R Ward

Babu O Narayanan

Rajiv R Ramaswami

Kesavamurthy Nagaraj

Ra'ed Awdeh

Osama S Aboul-Magd

Ornan A Gerstel

Robert William Keys

Frederic J Simard

Vasant Sahay

David Park

Yong-Qin Chen

Rani Indaheng

Automatic discovery and verification of optical communication links as well as isolation of link failures in an optical communication system.

Link discovery, verification, and failure isolation in an optical communication system

The present invention discloses novel network architectures for evolving traditional service provider networks. The network architecture of the invention has a transport layer including an optical network. At least one node of the network architecture includes a large packet switch that is coupled to the transport layer and to an access layer. The large packet switch aggregates a plurality of services from the access layer. The large packet switch also performs packet level grooming of the information from the services prior to transport of the information via the transport layer. The optical network performs restoration for the network architecture. In one embodiment, the optical network is an optical ring network including at least one optical switch and restoration is performed at the layer-0 (optical layer). In another embodiment, the optical network is a bi-directional line-switched ring (BLSR) utilizing a Synchronous Optical Network (SONET) standard and restoration is performed by the layer-1 (SONET layer). The network architectures of the invention by utilizing a large packet switch to perform service aggregation and packet level grooming, and by performing restoration either at the layer-0 (optical layer) or layer-1 (SONET layer), creates a single converged network that achieves the superior restoration performance needed for carrier grade availability but at much lower costs than traditional service providers which operate multiple overlay networks. Also disclosed are methods to optimize traditional service provider networks and the disclosed novel architectures of the invention.

Architectures for evolving traditional service provider networks and methods of optimization therefor

Apparatus and methods are disclosed for alignment of an input mirror and an output mirror in a photonic cross-connect.

Alignment laser for use in cross-connects

A method for calibrating a preferred disposition for a moveable first mirror of an optical switch core of a photonic crossconnect device relative to a second mirror thereof, the method comprising the steps of determining approximate geometric coordinates of the first mirror relative to the second mirror, effecting a laser light crossconnection between the first and second mirrors to produce data from which to provide first order corrections to refine the geometric coordinates, and effecting a further laser light crossconnection between the first mirror and a third mirror, to produce data from which to provide second order corrections to further refine the geometric coordinates, whereby to calibrate the first mirror such that upon initiation of a laser light crossconnection involving the first mirror, a switching element detects deviation of the first mirror from the preferred disposition thereof and effects corrective changes.

Method for calibrating photonic crossconnect device

The present invention discloses novel network architectures for evolving traditional service provider networks. The network architecture of the invention has a transport layer including an optical network. At least one node of the network architecture includes a large packet switch that is coupled to the transport layer and to an access layer. The large packet switch aggregates a plurality of services from the access layer. The large packet switch also performs packet level grooming of the information from the services prior to transport of the information via the transport layer. The optical network performs restoration for the network architecture. In one embodiment, the optical network is an optical ring network including at least one optical switch and restoration is performed at the layer-(optical layer). In another embodiment, the optical network is a bi-directional line-switched ring (BLSR) utilizing a Synchronous Optical Network (SONET) standard and restoration is performed by the layer-(SONET layer). The network architectures of the invention by utilizing a large packet switch to perform service aggregation and packet level grooming, and by performing restoration either at the layer-(optical layer) or layer-(SONET layer), creates a single converged network that achieves the superior restoration performance needed for carrier grade availability but at much lower costs than traditional service providers which operate multiple overlay networks. Also disclosed are methods to optimize traditional service provider networks and the disclosed novel architectures of the invention.

A method, apparatus, and computer program product for dynamic bandwidth allocation in a packet switched network having a ring architecture is disclosed. The method includes monitoring an occurrence of a contention of resources at a participating node and its neighboring nodes on the network. In response to a monitored occurrence of the contention of resources, bandwidth is dynamically allocated according to a fairness algorithm. Dynamically allocating bandwidth resolves contention of resources in a fair manner within given fairness constraints while enabling a prescribed maximum utilization of available bandwidth between the nodes. Lastly, the fairness algorithm generates fairness criteria in response to states that are local to the participating node and states obtained from the neighboring nodes.

Growing community of inventors

Sunnyvale, CA, United States of America

Humair Raza