Tellabs Operations, Inc.

Coriant Operations, Inc.

Thomas T Rarick

Chris R Zettinger

Weiying Cheng

David W Jenkins

Gary S Feutz

Devindran Rajakrishna

To perform protection switching between tunnels in a network, Y.1731-based APS messages are often sent from a management system to nodes at the tunnels' end-points. If the management system is located near one node (local node) and far away from the other node (remote node), the APS message, which operates at the Ethernet service layer, travels to the remote node slower than traffic over the tunnels. This slower transmission time may prevent the remote node from performing a switch within a desired timeframe. The disclosed embodiments include a 1:1 bidirectional VLAN-based protection arrangement that accomplishes a 50 millisecond switching time without using Y.1731-based APS messages. The embodiments accomplish this by sending a switching command from the management system to the local node and modifying a message already traveling from the local node to the remote node to include a switching message that causes the remote node to perform the switch.

Methods and apparatuses for performing protection switching without using Y.1731-based automatic protection switching (APS) messages

A method, apparatus, system, and computer program, for operating a network planning tool. The method includes recognizing at least one predetermined criteria being satisfied or triggered, and learning at least one network attribute, to be used in subsequent network planning. Various types of network attributes can be learned, such as, e.g., network element parameters, site parameters, link parameters, demand parameters, optical parameters, general parameters, and networking parameters. Example attributes may specify, e.g., a maximum number of add/drop channels, at least one alarm threshold, a maximum number of sites per network ring, a maximum number of add/drop sites per ring, and a maximum ring circumference. Others can specify a maximum light path distance, a routing tendency, at least one grooming node, or the like.

Procedure, apparatus, system, and computer program for network planning

A method and apparatus for discovering network paths sets a bit, normally used for purposes other than tracing a network path, in an overhead portion of a signal for causing state changes at nodes along a network path. The state changes are correlated with information about the signal to determine link connectivity between nodes to identify the network path. In a network of DS3 circuits, a non-critical alarm bit is set in a signal to transmit Remote Alarm Indications (RAI) which activate alarms at nodes of the network path. A response signal from the nodes can be sent through a network to a main node for correlation purposes. The method of discovering network paths can be used to update network path databases of network carriers and can be offered as a service to network carriers.

Growing community of inventors

Wheaton, IL, United States of America

Thomas T Rarick