A transmission device includes a symbol generator that generates a modulation symbol by mapping transmission data to a signal point arranged in a two-dimensional or three-dimensional color space; and an outputter that outputs an optical signal modulated according to the modulation symbol.

Methods and apparatus for monetizing a carrier network are provided. In an example, a wavelength service is captured from deployed network assets in a carrier network. A revenue factor (R), a capital expenditure factor (C), an operational expenditure factor (O), and a service level agreement factor (S) are selected from an analytic profile of the carrier network based on the wavelength service requirements. The R, C, O, and S factors are hexadecimal numbers, and can be weighted relative to each other. An index is calculated by concatenating the R, C, O, and S factors a prioritized order and converting the resultant hexadecimal number into a decimal number. The calculated index is assigned to the wavelength service. The index can be displayed, along with indices for other wavelengths on other paths, to a user in a graphical form.

Techniques for providing closed-loop control and predictive analytics in packet-optical networks are described. For example, an integrated, centralized controller provides tightly-integrated, closed-loop control over switching and routing services and the underling optical transport system of a communication network. In one implementation, the controller includes an analytics engine that applies predictable analytics to real-time status information received from a monitoring subsystem distributed throughout the underlying optical transport system. Responsive to the status information, the analytics engine applies rules to adaptively and proactively identify current or predicted topology-changing events and, responsive to those events, maps reroutes packet flows through a routing/switching network and control and, based on any updated bandwidth requirements due to topology changes, dynamically adjusts allocation and utilization of the optical spectrum and wavelengths within the underlying optical transport system.

The disclosure is directed to an optical telecommunications system which includes a central node and a plurality of user nodes. The central node provides the light necessary to enable communication between the user nodes. Within the central node is a multi-wavelength source, providing lights at different wavelengths, along with a wavelength selector. The wavelength selector selects one of the lights at different wavelengths from the multi-wavelength source for delivery to the user nodes such that the user nodes then modulate this light for transmission between nodes.

Methods and systems are provided for determining a shortest minimum regeneration path in an optical network. The method includes creating a virtual node at a source node, the source node communicatively coupled to a destination node through a plurality of nodes and links. The method includes traversing the virtual nodes, wherein traversing the virtual nodes comprises selecting an unvisited virtual node at a node; identifying a candidate virtual node from the unvisited virtual node; determining whether the candidate virtual node exceeds a maximum permitted weight; determining whether the candidate virtual node violates a shortest minimum regeneration path condition; and creating the new virtual node from the candidate virtual node if the candidate virtual node does not exceed the maximum permitted weight and if the candidate virtual node does not violate the shortest minimum regeneration path condition.

If wavelength defragmentation is performed during the operation of an optical network, an instantaneous interruption of a network arises; consequently, data are lost; therefore, an optical network control method according to an exemplary aspect of the present invention includes monitoring a data volume of a client signal to be transmitted using a plurality of optical subcarriers; and performing synchronously, depending on a variation in the data volume, an optical subcarrier changing process of changing an active optical subcarrier, of the plurality of optical subcarriers, to be used for transmitting the client signal, and a remapping process of remapping the client signal onto an active optical subcarrier after having been changed.

A system and method for performing an in-service optical time domain reflectometry test, an in-service insertion loss test, and an in-service optical frequency domain reflectometry test using a same wavelength as the network communications for point-to-point or point-to-multipoint optical fiber networks while maintaining continuity of network communications are disclosed.

A method for assigning a network path after receiving a connection request to connect a first node with a second node of a network. The method including evaluating a network utilization parameter of the network, such as a network load or blocking probability, at that point in time. If the network utilization parameter is below a minimum threshold level, the method includes carrying out the steps of identifying a set of n network paths through the network that connect the first node with the second node and are absent non-linear links, performing network path selection by selecting p network paths from the set of n network paths that have the best linear OSNR, and, selecting a network path from the set of p network paths that balances the wavelength utilization between the first node and the second node of a network.

The invention discloses a communication method includes: receiving, by the ONU by using the first port or the second port, a wavelength switching request message delivered by the OLT, where the wavelength switching request message carries second wavelength channel information and port information that is of the second port; switching, by the ONU, an operating wavelength channel of an optical module connected to the second port from a first wavelength channel to a second wavelength channel corresponding to the second wavelength channel information; and sending, by the ONU, a wavelength switching complete message to the OLT by using the first port. According to the communication method provided in embodiments of the present invention, quick wavelength switching is performed based on the second port, so that a service is not interrupted in a wavelength switching process, and user experience is better.

As network traffic grows and more data needs to be transmitted through a network, it is desired to use optical switching systems that allow for switching between a large number of nodes. An optical switching system according to one embodiment disclosed herein allows different nodes to transmit optical signals having the same optical wavelength, in order to accommodate a larger number of nodes. For example, one cluster of nodes may transmit data using optical wavelengths that are the same as optical wavelengths that may also be used by other clusters of nodes. A controller performs scheduling and reconfiguration in the optical switching system, as needed, e.g. in order to mitigate collisions.