2005results about "Electromagnetic network arrangements" patented technology

A system for data transport in a Distributed Antenna System (DAS) includes a plurality of remote Digital Access Units (DAUs) located at a Remote location. The plurality of remote DAUs are coupled to each other and operable to transport digital signals between the plurality of remote DAUs. The system also includes a plurality of central hubs. Each of the plurality of central hubs is in communication with one of the remote DAUs using an electrical communications path. The system further includes a plurality of transmit/receive cells. Each of the plurality of transmit/receive cells includes a plurality of remote hubs. Each of the remote hubs in one of the plurality of transmit/receive cells is in communication with one of the plurality of central hubs using an optical communications path.

One embodiment provides a system for power saving in an Ethernet Passive Optic Network (EPON). The system includes an optical line terminal (OLT), an optical network unit (ONU), a traffic-detection module configured to detect status of traffic to and from the ONU, and a power-management module configured to place the ONU in sleep mode based on the detected traffic status. The ONU includes an optical transceiver that includes an optical transmitter configured to transmit optical signals to the OLT and an optical receiver configured to receive optical signals from the OLT.

A system for powering a network element of a fiber optic wide area network is disclosed. When communication data is transferred between a central office (CO) and a subscriber terminal using a network element to convert optical to electrical (O-E) and electrical to optical (E-O) signals between a fiber from the central office and twisted wire pair, coaxial cable or Ethernet cable transmission lines from the subscriber terminal, techniques related to local powering of a network element or drop site by the subscriber terminal or subscriber premise remote powering device are provided. Certain advantages and/or benefits are achieved using the present invention, such as freedom from any requirement for additional meter installations or meter connection charges and does not require a separate power network.

An optical-fiber-network (OFN) radio-frequency identification (RFID) system for deploying and/or maintaining and/or provisioning service and/or locating faults in an OFN. The system includes a plurality of OFN components, and at least one RFID tag that includes RFID tag data that has at least one property of the OFN component associated with the RFID tag. The RFID tag data is written to and read from the RFID tags using one or more mobile RFID readers either prior to, during or after deploying the OFN components. An OFN-component-data database unit is used to store and process the RFID tag data and is automatically updated by the one or more mobile RFID readers. This allows for different maps of the OFN to be made, such as an inventory map and a maintenance map, and for the maps to be automatically updated. The OFN-RFID system allows for mobile automated operations and management of OFN components by service personnel, and provides for faster and more accurate OFN system deployment and maintenance.

One embodiment of the present invention provides a system that facilitates forwarding of packets in an Ethernet passive optical network (EPON), which includes a central node and at least one remote node. During operation, the system assigns a logical link identifier (LLID) to a remote node, wherein an LLID corresponds to a logical link between the central node and a remote node. The system also associates an LLID with a port of a switch within the central node, wherein the switch has a number of ports; wherein a port may be a physical port or a virtual port; and wherein the number of ports on the switch are divided into network-side ports and user-side ports. Upon receiving a downstream packet from a network-side port, the system searches a mapping table to determine whether one or more field values of the downstream packet correspond to any LLIDs or ports. If the one or more field values correspond to an LLID, the system assigns the LLID to the downstream packet and transmits the downstream packet to a remote node.

A SW (70) receives an Ethernet® signal from an outside of areas E and F. The SW (70) selects and outputs the obtained Ethernet® signal to any one of APs (91a to 91e) in accordance with a network structure managed by the SW (70). The AP (91a to 91e) converts the Ethernet® signal to an electrical signal type wireless LAN signal, which is in turn output to a main station (10). The main station (10) frequency-multiplexes the signal output from each of the APs (91a to 91e), and converts the signal to an optical signal, which is in turn output to sub-stations (20a and 20b) The sub-station (20a and 20b) transmits the signal transmitted from the main station (10) to a terminal in the form of a wireless radio wave. Thereby, when a plurality of communication areas are present, the accommodation capacity of an AP can be effectively utilized in each communication area.

Disclosed by the present invention is a system and method for optical fiber transmission. The switching portion of the present invention adopts the single-layered integrated switching technology so as to ensure a relatively simple and easy maintenance compared with the switching in a traditional communication network where said switching is made in the service network layer and the bearer network layer, respectively. Moreover, the present invention implements data transmission via optical fiber throughout the entire telecommunication system such that demands for bandwidth resources are satisfied during the whole data transmission process and the QoS (Quality of Service) of different services as well as rapid and un-blocking switching of the services are ensured in the telecommunication system. Therefore, the present invention can implement on-demand allocation of bandwidth resources, enhancing the flexibility in network resource management while a subscriber can apply for bandwidth resources based on its demand, which satisfies the individual needs of the user.

Provided are an apparatus and method for monitoring optical fibers of a passive optical network system including an optical line termination located in a central office, a remote node that is a local office, and optical network units on the subscriber side. The apparatus respectively allocates monitoring light wavelengths to optical network units such that optical fibers of the respective optical network units can be identified and monitored using the monitoring light wavelengths, combines a monitoring light having various wavelengths and a downward optical signal using the WDM coupler, and analyzes signal waveforms of the monitoring light having various wavelengths reflected from the optical network units, to detect the position of a defect generated on an optical line. Accordingly, it is possible to transmit optical signals and monitor the physical states of the optical fibers of the optical network units.

A data centre network, comprises a first group of optical ports for connection to respective servers of a first group of servers; a second group of optical ports for connection to respective servers of a second group of servers; a first lower passive optical routing element arranged to route optical communication signals between the first group of optical ports and a first lower optical communication path; a second lower passive optical routing element arranged to route optical communication signals between the second group of optical ports and a second lower optical communication path; an upper passive optical routing element arranged to: (i) route optical communication signals between the first lower optical communication path and an upper optical communication path, and (ii) route optical communication signals between the second lower optical communication path and the upper optical communication path.

A packet is routed by "dead reckoning" on a network having a generally regular topology. The packet is received at a node where a local routing decision is made. The packet is output in a direction selected according to the routing decision. The packet carries in addition to a destination address a directional flag indicating explicitly the preferred direction of onward travel and the routing decision is made using this flag. Several flags may be used, corresponding to different dimensions of the network.

The present disclosure provides hybrid packet-optical private network systems and methods for a private and dedicated multi-point Ethernet Private Local Area Network (EPLAN). The network systems and methods include a Layer 1 infrastructure service with the inclusion of reserved, dedicated packet switch capacity upon which clients can build their personal, private packet networks. In the systems and methods described herein, packet networking methods are not used to partition the isolated LAN connectivity. Instead, dedicated Ethernet Private LANs (EPLs) are defined between dedicated virtual switching instances (VSIs) that are defined, as necessary, within larger packet-optical switches. Each VSI is partitioned from the remainder of its packet switch fabric as a dedicated, private resource for a specific EPLAN. A packet network is then built by the customer on top of the private EPLAN bandwidth and operated as an isolated, private network with no influence by other carrier's network resources.

An optical transmitting apparatus is configured such that K pieces of output ports of optical path switching units whose input port is connected to k-th input transmission path are connected to first to K-th output transmission paths except for the k-th output transmission path and to the k-th input port of a dropping unit, and the optical path switching units and the dropping unit outputs light of wavelength which is part or all of WDM light received from said input port from a specific output port, and can output light having a wavelength different from that of the light output from said specific output port from an output port different from said specific output port. Accordingly, while largely reducing the number of optical fiber patch cords necessary in an optical transmitting apparatus and largely reducing the number of spare ports, the flexible expansion of apparatus function can be realized.

The present invention relates to a technology of an IP node for transferring IP packets accommodated in a wavelength division multiplexing optical signal. The optical IP node of the present invention includes a space switch unit supplied with a wavelength division multiplexing optical signal and a packet with another node destination and generating an optical signal with the self node destination and multiplexing the optical signal with another node destination and an optical signal caused by the packet together and generating the multiplexed signal, link failure detecting unit connected to an input side and an output side of the space switch unit, detecting link failure and generating a detection signal, an OAM packet transmitting unit for generating a monitoring packet at a predetermined time interval, and a traffic restoration control unit connected to the link failure detecting unit, selecting each optical signal depending on the wavelength in response to reception of the detection signal, switching the optical path and generating the optical signal. Each of the optical IP nodes carries out optical path switching on the wavelength division multiplexing optical signal and assignment of an IP packet to be transmitted to an optical signal and switching of the assignment. Thus, the number of optical wavelengths utilized for transmission can be reduced and the size of the optical IP node can be made small.

An architecture and method for performing coarse-grain reservation of lightpaths within wavelength-division-multiplexed (WDM) based photonic burst-switched (PBS) networks with variable time slot provisioning. The method employs extensions to the RSVP-TE signaling protocol, which uses various messages to reserve resources. A resource reservation request is passed between nodes during a downstream traversal of the lightpath route connecting a source node to a destination node via one or more switching nodes, wherein each node is queried to determine whether it has transmission resources (i.e., a lightpath segment) available during a future scheduled time period. Soft reservations are made for each lightpath segment that is available using information contained in a corresponding label. If all lightpath segments for a selected route are available, a reservation response message is sent back upstream along the route from the destination node to the source node. In response to receiving the response, the soft reservations are turned into hard reservations at each node.

Systems and methods for data transport, including receiving one or more signals into a reconfigurable and flexible rate shared rate multi-transponder network architecture, wherein the network architecture includes one or more transponders with multiple line side interfaces and one or more client side interfaces. The transponders are configured to map one or more signals to multiple parallel Virtual Ethernet Links, remove idle characters from the one or more signals, buffer one or more blocks of characters using an intermediate block buffer, activate and deactivate one or more portions of input/output electrical lanes of an Ethernet module, multiplex and demultiplex the one or more signals to and from the input/output electrical lanes to enable sharing of a single optical transceiver by multiple independent signals, and insert blocks of idle characters to enable transmission over a lower rate transmission pipe.

The present invention relates to an optical cross connect unit comprising M wavelength separating sections for receiving multiplexed optical signals each having N kinds of wavelengths different from each other through M optical fibers, respectively, and for wavelength-separating each of the multiplexed optical signals into N optical signals, M optical reproduction relay sections each for conducting an optical reproduction and relay in a manner of making a conversion of each of the N optical signals, wavelength-separated in each of the wavelength separating sections, into an electric signal and then modulating it with a desired optical wavelength, a refill section for mutually refilling M sets of optical signals optically reproduced and relayed in the optical reproduction relay sections, a focusing section for focusing the M sets of optical signals refilled in the refill section, and a light source unit for supplying input lights having desired wavelengths to be modulated in the M optical reproduction relay sections. The light source unit includes N light sources for outputting lights having the N kinds of optical wavelengths, a multiplexing and branching section for multiplexing the lights from the N light sources to produce a multiplexed light having N kinds of optical wavelength components and further for branching the multiplexed light into MxN lights to output them as multiplexed and distributed lights, M wavelength filter sections for distributively receiving N multiplexed and distributed lights of the MxN multiplexed and distributed lights branched in the multiplexing and branching section to output N lights due to the passage of only arbitrary wavelengths of the N kinds of optical wavelengths, and a wavelength setting control section for setting optical wavelengths, which pass through the wavelength filter sections, so that they differ from each other. The N lights from each of the M wavelength filter sections are supplied as the input lights. In the case that many light sources are necessary for the modulation processing by modulators or the like, this optical cross connect unit is also suitable because of using given wavelengths from a small number of light sources for a lot of modulation processing.

A WDM optical transmission system of the invention has a configuration where WDM light generated at a wavelength multiplexing station is transmitted via a plurality of stations such as optical add-drop stations, arranged on an optical transmission line, and control of the power of the optical signals of respective wavelengths included in the WDM light is performed in the wavelength multiplexing station and the optical add-drop stations. A device is provided which communicates between stations, optical signals including information related to the control state of the optical signal power in each station, so that after control of the optical signal power at an upstream station is complete, control of the optical signal power at the downstream station is executed. As a result, stable control in respective stations can be performed even at the time of increasing or decreasing the number of wavelengths.

In an optical network some optical nodes are fitted with optical switches. The optical switches support the optical coupling and decoupling of the optical nodes and the remainder of the optical network. Electrical power supply failures to a node result in the node being optically decoupled from the remainder of the optical network thereby allowing the remaining nodes to continue normal operation.

One embodiment of the present invention provides a method for facilitating asymmetric line rates in an Ethernet passive optical network (EPON) which includes a central node and at least one remote node. During operation, the system provides a downstream code-group clock, wherein each cycle thereof corresponds to a code group transmitted from the central node to a remote node. The system also provides an upstream code-group clock, wherein each cycle thereof corresponds to a code group received at the central node from a remote node. In addition, the system provides a multi-point control protocol (MPCP) clock, wherein the frequency ratio of the MPCP clock to the downstream code-group clock is different from the frequency ratio of the MPCP clock to the upstream code-group clock, thereby allowing the downstream transmission to be performed at a faster line rate than the upstream transmission line rate.

A network includes a plurality of interconnected nodes utilizing an all-broadcast architecture for a plurality of wavelengths therebetween; a routing protocol configured to compute a loop-free path through the plurality of interconnected nodes, wherein the loop-free path is computed for at least one wavelength of the plurality of wavelengths using routing constructs adapted to a photonic domain; and at least one blocking element configured to selectively block the at least one wavelength based on the computed loop-free path. A routing method photonic node are also disclosed.

A network comprising a large number of electronic edge nodes interconnected through bufferless optical switch planes so that a signal from any edge node to any other edge node traverses only one switch plane scales to a capacity of hundreds of petabits per second while providing global geographic coverage. Each edge node is time-locked to each optical switch plane to which it connects to enable loss-free time-sharing of the network core despite the absence of buffers in the core. In an alternate implementation, a relatively small number of electronic switch units may be employed in a predominantly-optical core. In addition to scalability and high performance, the simple structure of the network significantly simplifies addressing and routing.