Accommodation design for wavelength and sub- paths in a communication network is performed. If sub- path accommodation is possible according to search for a wavelength path present in a single-hop logical route, the accommodation in the wavelength path is executed. If sub- path accommodation is possible according to search for a wavelength path present in a multi-hop logical route, a logical route is selected based on the wavelength path and the sub- path is accommodated in the wavelength path. Additionally, each physical route suitable for the sub- path accommodation is searched for. If the route can accommodate a wavelength path set in a single-hop logical route by available wavelength allocation, the sub- path is accommodated in the wavelength path. Furthermore, routes in consideration of overlapping of nodes, pipelines, and links and operation rate are selected based on information about the start and end nodes of each of redundant routes.

A computerized system for performing preparation operations for a maintenance activity that causes a disruption in a communication path of traffic over a multi-layer network. The system comprising: a maintenance tool configured to coordinate maintenance activities of the multi-layer network based on maintenance activity data, a storage unit to store the maintenance activity data; and a multi-layer control system comprising a processor, wherein said processor is configured to: receive from the maintenance tool an indication that one or more maintenance activities are required on an indicated optical resource, determine an affected optical path, determine an affected IP link utilizing said affected optical path; remove traffic from the affected IP link; remove the affected optical path; activate an alternative optical path; configure the packet switching layer to utilize the alternative optical path; and repeat for each affected optical path and each affected IP link.

A multi-layer network planning system can determine a set of regenerator sites (RSs) that have been found to cover all paths among a set of nodes of an optical layer of a multi-layer network and can determine a set of candidate RSs in the optical layer for use by the links between a set of nodes of an upper layer, wherein each RS can be selected as a candidate RS for the links. The system can determine a binary path matrix for the links between the set of nodes of the upper layer. The system can determine a min-cost matrix that includes a plurality of min-cost paths. The system can determine a best RS from the set of candidate RSs and can move the best RS from the set of candidate RSs into the set of RSs for the links. The system can then update the binary path matrix.

In the elastic optical network, there has been the problem that processing steps increase that are required to re-optimize client signals to be concentrated; therefore, an optical network controller according to an exemplary aspect of the present invention includes reallocation detection means for monitoring an operation status of at least one of an optical communication channel and an optical node device that constitute an optical network, and determining, based on the operation status, whether or not to reallocate a client signal accommodated in an optical path set in the optical network; design-candidate exclusion means for designating, as a design exclusion object, at least one of the optical communication channel and the optical node device that are associated with an optical path targeted for reallocation that accommodates the client signal that the reallocation detection means has determined to reallocate; optical path design means for determining an alternative route for the optical path targeted for reallocation from among routes with the exception of the design exclusion object; traffic reference means for determining the client signal to be reaccommodated in an optical path on the alternative route, referring to demand traffic accommodated in the optical path targeted for reallocation; and line concentration design means for constituting line-concentration traffic in which traffic having been allocated to the alternative route and the demand traffic are concentrated, wherein the traffic reference means determines a reallocation optical path in which an optical path candidate with number of occupied wavelength slots increasing is excluded from optical path candidates on the alternative route, and the optical path design means determines wavelength allocation of the reallocation optical path so as to accommodate the line-concentration traffic.

A network system for a data center is described in which a switch fabric may provide full mesh interconnectivity such that any servers may communicate packet data to any other of the servers using any of a number of parallel data paths. Moreover, according to the techniques described herein, edge-positioned access nodes, optical permutation devices and core switches of the switch fabric may be configured and arranged in a way such that the parallel data paths provide single L2/L3 hop, full mesh interconnections between any pairwise combination of the access nodes, even in massive data centers having tens of thousands of servers. The plurality of optical permutation devices permute communications across the optical ports based on wavelength so as to provide, in some cases, full-mesh optical connectivity between edge-facing ports and core-facing ports.

A computer-implemented method of requesting a path on a flexi-grid network comprises: sending, by a path computation client (PCC), a request for a path to a path computation element (PCE), the request including the request including: a label that identifies spectrum to be restricted from use in the path; and a channel spacing field; and receiving, by the PCC and from the PCE, a response to the request, the response including an identifier of an assigned path on the flexi-grid network.

A rule indicates that data having particular characteristics be automatically routed to a particular destination. When software on a switching device detects a new data stream, it is analyzed to determine whether it has characteristics specified by the rule. If it does, the packet is encapsulated with a special tag, indicating that the packet should be routed to the new destination. Also, an entry is added to a quick-lookup table in the switching device. The entry indicates that future packets in the data stream that have the same source and destination port and address should also be routed to the new destination.

This application discloses a flow entry generating method and apparatus. The method includes: receiving a service path establishment request, where the service path establishment request includes a constraint, a source device, and a target device; finding, in a data transmission network according to a cross-layer information model, a service path that meets the constraint and is from the source device to the target device, where the cross-layer information model is a model that describes, at a same layer, an overall topology relationship between an IP layer and an optical layer; and generating a respective corresponding flow entry for each forwarding device in the service path, and sending the flow entry to a corresponding forwarding device. This application can greatly reduce time complexity of computing the service path, and improve efficiency of computing the service path, thereby improving efficiency of generating a flow entry.

Systems and methods for allocating optical circuits on optical mesh networks are disclosed herein. For example, the disclosed methods include identifying a new circuit to be added to a mesh optical network and identifying a set of potential paths for the new circuit. For each optical link in each identified potential path, costs are determined for a plurality of frequency slots of allocating the new circuit to a potential path including the optical link. The cost of allocating a given frequency slot on a given optical link is determined in part based on the lengths of optical circuits that can traverse the given optical link using that frequency slot. Total cost values are calculated for allocating available frequency slots over each of the identified potential paths, and one of the identified potential paths and one or more of the available frequency slots are allocated for the new circuit.

A method for distributed allocation of data paths in an optical network (100) including optical switches (30, 32, 130) connected by optical links (44, 140), includes receiving a request for a data path for connecting a source node (10) and a destination node (20). In in response to the request, one or more queries are sent, the queries corresponding to one or more candidate optical circuits that connect the source node and the destination node, the queries requesting one or more processors (230) to configure the optical switches along the candidate optical circuits to reserve optical channels on the optical links of the candidate optical circuits for the requested data path. An optical circuit is identified from among the candidate optical circuits, in which all the optical channels for the requested data path have been reserved successfully. The requested data path is established over the identified optical circuit.