An all-optical time slice switching method based on time synchronization is provided. With the method, continuous data streams in an optical network are assembled to time domain periodic optical time slices and are transmitted in an asynchronous transmission mode. Network nodes obtain high precision synchronization time via a network and control optical switches to switch arriving optical time slices to a target port at precise time points periodically, therefore all-optical switching is implemented. When a connection request arrives, an available path, a wavelength and time slots to be occupied are calculated by a source node according to information on available time slots of the optical network, and the time slots are reserved by a connection management module. After the time slots are reserved, the source node send optical time slices carrying services periodically at reserved time slots. A destination node restores the optical time slices to the data streams.

A number of users interface with a network via a multiplex module, on a communication path established between the multiplex module and a point of presence. Some users may be served by one or more first channels of the communication path while one or more remaining users may be served by one or more additional channels of the communication path. Users having a basic service level agreement may be served by the first channels while users having an extended service level agreement may be served by the one or more additional channels. Allocation of users to distinct channel types based on their service level agreements may apply at a primary point of presence or may apply at a redundant point of presence.

A network of global coverage, scalable to an access capacity of hundreds of petabits per second, is configured as independent bufferless switches with spectral routers connecting edge nodes to the switches. The switches are logically arranged in at least one matrix, the spectral routers are logically arranged into a matrix of upstream spectral routers and a matrix of downstream spectral routers. Each edge node has a link to an upstream spectral router in each column of the matrix of upstream spectral routers and a link from a downstream spectral router in each row of the matrix of downstream spectral routers. Preferably, all sets of edge nodes connecting to the upstream spectral routers are selected to be mutually orthogonal. Each switch is coupled to a respective switch controller and a respective time indicator. Each switch controller entrains time indicators of a set of subtending edge nodes to enable coherent switching.

There is provided a communication apparatus including a hardware processor configured to: count numbers of transmissions and receptions of a measurement frame assigned between frames when a communication of an active system is performed, by an active system counter, count numbers of transmissions and receptions of the measurement frame when a communication of a standby system is performed, assign switchover indication information for indicating an occurrence of the switchover from the active system to the standby system, to the measurement frame to be transmitted to other communication apparatus, and measure a data loss based on a count value of the active system counter or the standby system counter, by excluding frames transferred during a period of time from a transmission of the switchover indication information to a reception of the reception indication information transmitted from the other communication apparatus which has received the switchover indication information, from a measurement target.

In one embodiment, a method of photonic frame scheduling includes receiving, by a photonic switching fabric from a top of rack (TOR) switch, a frame request requesting a time slot for switching an optical frame to an output port of a photonic switch of the photonic switching fabric and determining whether the output port of the photonic switch is available during the time slot, and generating a contention signal including a grant or a rejection, in accordance with the determining. Also, the method includes assigning the time slot to the TOR switch for the output port of the photonic switch, when the contention signal includes the grant, transmitting, by the photonic switching fabric to the TOR switch, the contention signal and receiving, by the photonic switching fabric from the TOR switch, the optical frame during the time slot, when the contention signal includes the grant.

A switch module and optoelectronic switch incorporating the same. The optoelectronic switch includes an N-dimensional array of switch modules arranged in a topology in which each switch module is a member of N sub-arrays, the sub-arrays defined with reference to the coordinates of the constituent switch modules, and wherein all of the members of each sub-array are connected by an active switch, which in some embodiments may be an optical active switch or an electronic active switch.

Multiple switch planes, each having meshed bufferless switch units, connect source nodes to sink nodes to form a communications network. Each directed pair of source and sink nodes has a first-order path traversing a single switch unit in a corresponding switch plane and multiple second-order paths each traversing two switch units in one of the remaining switch planes. To reduce processing effort and minimize requisite switching hardware, connectivity patterns of source nodes and sink nodes to the switch planes are selected so that each pair of source node and sink node connects only once to a common switch unit. Widely-varying flow rates may be allocated from each source node to the sink nodes. To handle frequent changes of flow-rate allocations, in order to follow variations of traffic distribution, a high-throughput scheduling system employing coordinated multiple scheduler units is provided in each switch plane.

A central node for digital subscriber line access multiplex. The central node supports a plurality of subscriber devices and comprises: a digital interface for upstream communication; a converter device for each one of the subscriber devices wherein each converter device comprises an A/D, analogue to digital, converter and a D/A, digital to analogue, converter; an analogue optical interface for communication of analogue signals for all of the subscriber devices with an intermediate distribution node for digital subscriber line access multiplex; a digital multiplexer/demultiplexer connected between the digital interface and the plurality converter devices; an analogue multiplexer/demultiplexer connected between the analogue optical interface and the plurality of converter devices; and a control signal generator connected to the analogue multiplexer/demultiplexer, wherein the control signal generator is arranged to generate an analogue control signal for controlling time division duplex operation at the intermediate distribution node.

A data forwarding method and apparatus, a chip, and a non-transitory computer-readable storage medium are disclosed. The method may include: determining, according to a data switching request, an interface to be switched off and a target interface to be switched to (S110), where the interface to be switched off and the target interface to be switched to send same data and include a same number of data ports; and controlling, according to timestamp jumping points of the data ports included in the interface to be switched off and the target interface to be switched to, data forwarded to an optical transport network to be switched from the interface to be switched off to the target interface to be switched to (S120).