Abstract: A method of communicating information regarding a failure is disclosed. The method includes generating failure information. The failure affects a virtual path, which is between a first node and a second node. A first zone includes the first node, and a second zone includes the second node. The failure information can include, for example, a zone identifier and/or an action code.

Abstract: A signal router, configured to receive information carried by a first signal and transmit the information on a second signal, is described. The signal router, using routing information it gathers, selects the second signal from a number of signals, with the first and the second signals differing in at least one physical characteristic. The signal router operates in a network of a number of such signal routers, and so each one of the signal routers is coupled to at least one of the other signal routers. The routing information is used to create a circuit from a first one of the signal routers to a second one of the signal routers. Once the circuit is created, the information is routed over the circuit. According to one aspect of the present invention, the signals are optical signals.

Abstract: A method for restoring a virtual path, provisioned between a source and a target node, in a mesh optical network is described. The method, in one embodiment, forwards a resource request in the network to identify an alternate route. Each node identifies and allocates resources for failed virtual path and the virtual path is provisioned using these resources. The constant update of nodal topology by each node may provide a fast identification of nodes with required bandwidth for failed virtual path.

Abstract: A method of operating a network is described. The network includes a number of nodes connected by a number of links. A method according to the present invention provisions a virtual path between a first and a second one of the plurality of nodes by: identifying the first and the second nodes, discovering a physical path from the first node to the second node, and establishing the virtual path. The method discovers a physical path from the first node to the second node by automatically identifying nodes forming the physical path. The method establishes the virtual path by configuring a set of connections between the nodes forming the physical path.

Abstract: A method for operating a network and a network architecture implementing the method are described. The method, in one embodiment, begins by grouping a plurality of nodes into zones, where the network includes the plurality of nodes. At least one of the nodes in each one of the zones is one of a plurality of boundary nodes, and each of the boundary nodes in each one of the zones is coupled to a boundary node in another of the zones by one of a first number of inter-zone optical links. One of the zones includes a number of nodes, each of which is coupled to at least one other of the nodes by one of a second number of intra-zone optical links. Next, a non-boundary node is configured to transmit network information to other of the nodes. The non-boundary node is a node in the zone that is not a boundary node. Finally, a boundary node in the zone is configured to limit transmission of the network information through itself to other of the boundary nodes.

Abstract: A method of providing network services is described. The network includes a number of nodes, each one of which is coupled to at least one other of the nodes by at least one of a number of optical links. The network is preferably capable of supporting a number of virtual circuits. The method begins with the receiving of a request for a virtual circuit between a first node and a second node of the network. Preferably, the request specifies a quality of service of the virtual circuit. Next, the availability of network resources for supporting a virtual circuit at the requested quality of service is determined. Assuming sufficient network resources are available for support of the virtual circuit, the request is then serviced by provisioning (and maintaining) the requested virtual circuit. Servicing the request preferably includes actions such as provisioning, maintaining, and restoring the virtual circuit, using the requested parameters.

Abstract: A method of operating an optical network is described. The network includes a number of nodes connected by a number of links. A method according to the present invention provisions a virtual path between a first and a second one of the plurality of nodes by: identifying the first and the second nodes, discovering a physical path from the first node to the second node, and establishing the virtual path. The method discovers a physical path from the first node to the second node by automatically identifying nodes forming the physical path. The method establishes the virtual path by configuring a set of connections between the nodes forming the physical path.

Abstract: A method is provided to allocate bandwidth from a first node to a second node in a optical network. The method begins by accepting a request from an end-user, who requests a virtual path between the first node and the second node. The first and second nodes are ones of a number of such nodes. Each one of the nodes is coupled to at least one other node by at least one of a number of optical links. The nodes and links form the optical network. The virtual path has a bandwidth requirement associated therewith. Next, the service provider determines an amount of bandwidth available between the first and the second nodes. The service provider then allocates at least a portion of the amount of bandwidth available between the first and second nodes equal to the bandwidth requirement, so long as the bandwidth requirement is not greater than the amount of bandwidth available between the first and second nodes.

Abstract: A method for restoring a virtual path, provisioned between a source and a target node, in a zoned mesh optical network is described. The method, in one embodiment, allocates a primary and a secondary physical path to the virtual path. The two physical paths are node and link disjoint. In case of a failure on one physical path, the network switches the virtual path to the other physical path. The alternate path can be shared among various virtual paths during the restoration.

Abstract: A method and apparatus for restoring a virtual path are disclosed. The method includes identifying an alternate physical path and determining whether the alternate physical path is able to support the virtual path by determining whether each node of the second subset of nodes has sufficient resources necessary to support the virtual path. The virtual path is over a physical path in an optical network, and the optical network includes a number of nodes. The physical path includes a first subset of nodes of the nodes. The alternate path includes a second subset of nodes of the nodes and is between a first node and a second node of the first subset of nodes.

Abstract: A method of operating an optical network is described. The network includes a number of nodes connected by a number of links. A method according to the present invention provisions a virtual path between a first and a second one of the plurality of nodes by: identifying the first and the second nodes, discovering a physical path from the first node to the second node, and establishing the virtual path. The method discovers a physical path from the first node to the second node by automatically identifying nodes forming the physical path. The method establishes the virtual path by configuring a set of connections between the nodes forming the physical path.

Abstract: A method for reserving resources for restoration of a failed virtual path in a mesh optical network is defined. The method in one embodiment, defines multiple classes of service for the virtual path by allocating certain path performance, path implementation and path restoration related attributes to the virtual path. Each class of service defines the relative restoration priority of the virtual path. In a case of a path failure, the class of service is used by each node, to determine how the virtual path will be restored. The higher class of service guarantees a maximum acceptable restoration time during a path failure.

Abstract: A method of communicating information regarding a failure is disclosed. The method includes generating failure information. The failure affects a virtual path, which is between a first node and a second node. A first zone includes the first node, and a second zone includes the second node. The failure information can include, for example, a zone identifier and/or an action code.

Abstract: A method of managing a communications system is disclosed. The method begins with the creation of a resource control block corresponding to a resource of the communications system. The communications system includes, for example, a processor and a resource coupled to the processor. The resource control block maintains information regarding the resource. The method also provides for the maintenance of the resource control block. The processor is configured to maintain the resource control block, and the resource control block is maintained by the processor in response to communications (e.g., a keep-alive message) between the processor and the resource. This embodiment can also include the creation of a processor resource control block corresponding to the processor that is created by the controller in response to a power-up message from the resource. The resource can be, for example, a hardware component of the communications system.

Abstract: A method for restoring a virtual path, provisioned between a source and a target node, in a zoned mesh optical network is described. The method, in one embodiment, allocates a primary and a secondary physical path to the virtual path. The two physical paths are network element and link disjoint. In case of a failure in one physical path, the end nodes switch the virtual path to the other physical path.

Abstract: A method for finding a path in a network is disclosed. The network includes a plurality of nodes and a plurality of links and each one of the plurality of nodes is coupled to at least one other of the plurality of nodes by at least one of the plurality of links. Such a method generates at least one path cost data set and accessing the path cost data set to provide the requisite path information. The path cost data set represents a path cost between a root node of the nodes and destination node of the nodes. The path begins at the root node and ends at the destination node. The generation and accessing operations are performed in such a manner that a minimum-hop path and a minimum-cost path can be determined from the at least one path cost data set. The minimum-hop path represents a path between the root node and the destination node having a minimum number of hops. The minimum-cost path represents a path between the root node and the destination node having a minimum cost.

Abstract: A switching apparatus is disclosed that employs a relatively simple and inexpensive switching matrix, but which avoids interruption of existing connections when connections are added or removed. The switching matrix switches errorlessly by controlling the point in time at which switching occurs. Using such a technique, switching can be performed without disturbing the connections already configured in the switching matrix, and so is referred to herein as being non-blocking. Optionally, the incoming data can be rearranged to provide a larger window of time in which the switching matrix can be switched. In the case of a switch using an optical backplane, this also allows more time for various components of the system (e.g., clock/data recovery units) to re-acquire lock. The switching apparatus includes a switching matrix and control circuitry. The switching matrix has a matrix input, a control input and a number of matrix outputs, and is configured to receive an information stream at the matrix input.

Abstract: A method is provided to allocate bandwidth from a first node to a second node in a optical network. The method begins by accepting a request from an end-user, who requests a virtual path between the first node and the second node. The first and second nodes are ones of a number of such nodes. Each one of the nodes is coupled to at least one other node by at least one of a number of optical links. The nodes and links form the optical network. The virtual path has a bandwidth requirement associated therewith. Next, the service provider determines an amount of bandwidth available between the first and the second nodes. The service provider then allocates at least a portion of the amount of bandwidth available between the first and second nodes equal to the bandwidth requirement, so long as the bandwidth requirement is not greater than the amount of bandwidth available between the first and second nodes.

Abstract: A method of providing network services is described. The network includes a number of nodes, each one of which is coupled to at least one other of the nodes by at least one of a number of optical links. The network is preferably capable of supporting a number of virtual circuits. The method begins with the receiving of a request for a virtual circuit between a first node and a second node of the network. Preferably, the request specifies a quality of service of the virtual circuit. Next, the availability of network resources for supporting a virtual circuit at the requested quality of service is determined. Assuming sufficient network resources are available for support of the virtual circuit, the request is then serviced by provisioning (and maintaining) the requested virtual circuit. Servicing the request preferably includes actions such as provisioning, maintaining, and restoring the virtual circuit, using the requested parameters.

Abstract: A method of operating an network is described. The network includes a number of nodes connected by a number of links. A method according to the present invention provisions a virtual path between a first and a second one of the plurality of nodes by: identifying the first and the second nodes, discovering a physical path from the first node to the second node, and establishing the virtual path. The method discovers a physical path from the first node to the second node by automatically identifying nodes forming the physical path. The method establishes the virtual path by configuring a set of connections between the nodes forming the physical path.