Cisco Technology, Inc.

Cicso Technology, Inc.

David A Hillard

Steven Harold Goody

Anix Anbiah

Carmel Chi Him Lau

Michael F Davis

Xiao Pin Nie

Robert L Bortolotto

Daniel Scott Terhune

Venkataraman Anand

The invention provides a method and system for enhancing the capability to optimally route VT circuits over SONET networks. The invention discloses a method for identifying Network Elements (NEs) that have VT capability (i.e., VT cross connect capability) and, when desired or required for VT circuit routing, manually or automatically topologically interconnecting these NEs by STS-1 circuits called VT Tunnels. Once interconnected, these VT Tunnels are suitable for supporting user VT traffic without the network operator being required to upgrade non-VT NE with VT capability or without having to exhaust the limited pool of available VT cross connects on one or more NEs.

Method and system for optimized routing and protection of VT traffic in SONET networks

The present invention discloses a method and apparatus for automatically provisioning data stitching circuits within a network element (NE). Data circuits are defined as the interface cards within NE that are receiving a particular data stream. Data stitching circuits are defined as data circuits that are provided with a destination point and a next destination point for each interface card. The NE creates a data-stitching matrix that identifies a path (i.e., destination and next destination) for the data stream to follow. The matrix is used by a cross-connect to reroute the data stream around one or more inoperable interface cards. When interface cards within the NE request to be provisioned into or out of a data stitching circuit the NE automatically updates the data-stitching matrix.

Method and apparatus for automatically provisioning data circuits

The present invention discloses a method and apparatus for rerouting high-speed telecommunications signals within a network element (NE). Data circuits are defined as the interface cards within the NE that receive a particular data stream. In the event that one or more of the interface cards associated with a particular data circuit is removed, the NE can reroute the data stream so that the data circuit is maintained. The rerouting is accomplished by creating a stitching table, which defines the previous stitch and next stitch for each port on a cross-connect unit. Thus, when one stitch is lost, the table enables the apparatus to reroute the data stream around the lost stitch. That is, the data circuit is stitched together when one or more elements of the data circuit are removed.

Method and apparatus for rerouting telecommunications signals

The invention comprises a method for computing the shortest protectable paths in communication networks, and a method for establishing and defining protected paths. The invention utilizes a new algorithm to exclude from consideration as the &ldquo;shortest path&rdquo; between two network elements, a path for which adequate protection cannot be established. Such an unprotectable path will contain one or more unprotectable links. These unprotectable links can be identified and excluded based upon whether or not the link is a member of a loop. Because there are several more computational steps in defining the protected paths, after the shortest path has been found, the initial exclusion of unprotectable path segments from consideration eliminates the potential waste of computational resources leading to a more rapid and efficient routing and provisioning of reliable network paths and circuits.

Method and apparatus for eliminating unprotectable paths from consideration during computation of a protectable shortest path tree

A network management system ( ) automatically heals incomplete circuits through a network element ( C) in response to a network manager's command to heal circuits interrupted at the network element.

Growing community of inventors

Novato, CA, United States of America

David A Hillard