The present invention proposes a new method for solving the problem of fault tolerance. This new approach obtains all secondary routes assigned to each possible connection (user). The secondary routes replace the main routes when these are affected by at least one fault, which keeps the users connected as long as, for each connection, there is at least one route with operative links for reaching the destination nodes thereof. This new approach solves the general case of an arbitrary set of simultaneous link failures. The method also assesses the number of wavelengths for each link of the network, so that the probability of any connection request from a determined user c being blocked is less than a predefined threshold β.sub.c, despite the possible occurrence of the fault scenario.

An optical access network includes an optical hub having at least one processor. The network further includes a plurality of optical distribution centers connected to the optical hub by a plurality of optical fiber segments, respectively, and a plurality of geographic fiber node serving areas. Each fiber node serving area of the plurality of fiber node serving areas includes at least one optical distribution center of the plurality of optical distribution centers. The network further includes a plurality of endpoints. Each endpoint of the plurality of endpoints is in operable communication with at least one optical distribution center. The network further includes a point-to-point network provisioning system configured to (i) evaluate each potential communication path over the plurality of optical fiber segments between a first endpoint and a second endpoint, and (ii) select an optimum fiber path based on predetermined path selection criteria.

A method and device for computing a global concurrent optimization path, and a non-transitory computer-readable storage medium are disclosed. The method may include: computing, by a PCE, an actual path for each of at least one service sequentially based on a topology to serve as an actual best path; allocating, by the PCE, an actual spectrum resource sequentially for the actual path, to serve as an actual best spectrum resource; computing, by the PCE, an actual target value for all services in accordance with a target function, to serve as an actual best target value; and reordering a subset of services, recomputing an actual path for each of the subset of services and reallocating a spectrum resource, recomputing an actual target value for all services, updating the actual best target value, and updating the actual best path and the actual best spectrum resource, by the PCE.

The present invention provides a protection method and system in flexible bandwidth optical networks with multi-core fiber. The method includes steps of: selecting an appropriate working path for a connection request, and selecting a working core as a transmission channel on the working path; allocating, on the selected working path and working core, a spectrum resource that satisfies spectral continuity, spectral consistency, and a crosstalk threshold constraint; selecting, for the connection request, a dedicated protection path that does not intersect a link of the working path, and selecting a protection core as a transmission channel on the protection path; and finally, allocating, on the selected protection path and protection core, the spectrum resource that satisfies the spectral continuity, the spectral consistency, and the crosstalk threshold constraint.

Provided is an optical communication system configured as an optical ring network including: a first optical communication device configured to transmit a first optical signal having a first wavelength in a first direction, and to transmit a second optical signal having a second wavelength in a second direction opposite to the first direction; and a second optical communication device configured to generate a first reflected signal by reflecting the first optical signal when the first optical signal is received, to generate a second reflected signal by reflecting the second optical signal when the second optical signal is received, and to transmit the first and second reflected signals to the first optical communication device, wherein the first optical communication device analyzes a connection state of the second optical communication device based on the first and second reflected signals.

Path computation systems and methods are provided herein. According to one embodiment, a method includes obtaining topological information representing a topology of at least a portion of a network. The topological information includes one or more nodes and one or more links, each link configured to connect a node with a neighboring node. Each node includes a plurality of internal components and a plurality of connections configured to interconnect the internal components. The method further includes running path computation through the topological information to determine a plurality of paths from a first internal component to a second internal component. Also, the method includes applying elimination rules during the path computation to filter out one or more paths detected as being invalid. The elimination rules are based on one or more predetermined path sequences that include at least two hops involving an unviable sequence of specific types of internal components.

A dark fiber design tool for hardware, circuits, and paths is provided. A method can include generating, by a system comprising a processor, a data record that identifies respective equipment of a group of dark fiber equipment that have been assigned for a development of new dark fiber network infrastructure usable via a communication network; generating, by the system, a circuit plan representing optical connections between the respective ones of the group of dark fiber equipment as determined based on a first constraint defined by rules; and associating, by the system, respective optical wavelength paths with respective connections of the optical connections of the circuit plan based on a second constraint defined by the rules.

The present invention proposes a new method for solving the problem of fault tolerance. This new approach obtains all secondary routes assigned to each possible connection (user). The secondary routes replace the main routes when these are affected by at least one fault, which keeps the users connected as long as, for each connection, there is at least one route with operative links for reaching the destination nodes thereof. This new approach solves the general case of an arbitrary set of simultaneous link failures. The method also assesses the number of wavelengths for each link of the network, so that the probability of any connection request from a determined user c being blocked is less than a predefined threshold β.sub.c, despite the possible occurrence of the fault scenario.

The invention relates to a novel method for determining the set of routes that allow each network user to transmit. The method is more efficient than the existing methods, in terms of number of wavelengths, and due to the fixed routing strategy used, its implementation is simple, and its online operation is very fast.

Implementations described and claimed herein provide systems and methods for a configurable optical peering fabric to dynamically create a connection between participant sites without any physical site limitations or necessity of specialized client and network provider equipment being located within such a facility. Client sites to a network may connect to a configurable switching element to be interconnected to other client sites in response to a request to connect the first client site with a second site, also connected to network, via the switching element. A request may trigger verification of the requested and, upon validation, transmission of an instruction to the switching element to enable the cross connect within the switching element. The first site and the second site may thus be interconnected via the switching element in response to the request, without the need to co-locate equipment or to manually install a jumper between client equipment.