Class / Patent application number | Description | Number of patent applications / Date published |
398003000 | In a ring or loop | 32 |
20080273872 | SINGLE-FIBER PROTECTION IN TELECOMMUNICATIONS NETWORKS - A solution for detecting and recovering from a failure in a protected single-fiber passive optical network. A detector is used to detect the degradation in power level of optical signals. Furthermore, the invention discloses a variable symmetric split ratio approach to improve the number of splits (e.g. the number of ONUs). A single-fiber passive optical network is disclosed that uses a plurality of passive nodes connected in the optical fiber between the interfaces, wherein in the passive nodes 2-by-2 splitters/combiners are used to couple optical power from and into the optical fiber at a predetermined split ratio. | 11-06-2008 |
20090052890 | METHOD AND APPARATUS FOR DETECTING AND REMOVING ORPHANED PRIMITIVES IN A FIBRE CHANNEL NETWORK - A method and system for detecting orphaned CLS primitives in a fibre channel network having a fibre channel switch element coupled to an arbitrated loop is provided. The method includes, sending an OPN primitive to a switch element pore's own AL_PA to open a connection with itself; and determining if a CLS primitive is received within a loop a latency period. If a CLS primitive is received within the latency period then the CLS primitive is classified as an orphan and the orphaned CLS primitive is removed by the switch element by enabling a firmware based removal feature. The switch element includes a port that arbitrates for the arbitrated loop ownership and sends an OPN primitive to its own AL_PA. | 02-26-2009 |
20090074403 | SELF-HEALING RING-BASED PASSIVE OPTICAL NETWORK - A self-healing ring-based passive optical network (PON) including an optical fiber ring, an optical line termination (OLT), and a plurality of optical network units (ONUs) is provided. The optical fiber ring has a first end and a second end. The OLT is coupled to the first and the second end. The OLT receives a first signal from the first end or the first and the second end and transmits a second signal to the first end or the first and the second end. Each of the ONUs has a third end and a fourth end both coupled to the optical fiber ring. Each of the ONUs receives the second signal from the third and the fourth end and transmits the first signal to the third and the fourth end. The ONUs connect to the OLT through the optical fiber ring so as to form a ring-based PON. | 03-19-2009 |
20090129771 | DESIGN METHOD FOR WDM OPTICAL NETWORKS INCLUDING ALTERNATE ROUTES FOR FAULT RECOVERY - A procedure for designing WDM optical networks provides both working circuits and protection circuits for carrying traffic demands between node pairs. The protection circuits are activated for the purpose of network recovery in case of a fault on a working circuit. Each protection circuit is link-disjoint, and preferably node-disjoint, from its corresponding working circuit. The network is subdivided into logically defined rings, such that each working and protection circuit lies on one or more of the rings. In particular embodiments of the invention, the joint routing of circuits is carried out so as to minimize the total length of the working and protection circuits according to a length that includes a weight for each link. The weight is selected to promote the efficient packing of optical fibers with wavelength channels. | 05-21-2009 |
20100111520 | MULTIPLE INTERCONNECTED BROADCAST AND SELECT OPTICAL RING NETWORKS WITH REVERTIBLE PROTECTION SWITCH - Optical communication networks having multiple interconnected optical rings and optical protection switching mechanism to reduce communication delays and improve optical signal-to-noise ratios. Optical ring networks using variable optical attenuators for protection switching are also described. | 05-06-2010 |
20100124417 | NODE APPARATUS - There is provided a node apparatus having a plurality of interface units for interfacing to a transmission line, switch units of a work system and a protection system for switching signals of the transmission line, and a service selector used to relieve a network failure over ring networks interconnected by node apparatuses, the node apparatus including a first controller for controlling the service selector in the switch units, and a second controller for controlling setting information of alarm detection in case of using the service selector in the interface units. | 05-20-2010 |
20110091201 | METHOD AND DEVICE FOR REALIZING INTERACTION OF OPTICAL CHANNEL DATA UNIT PROTECTION TANGENT RINGS - A method for realizing interaction of optical channel data unit (ODUk) protection tangent rings are provided. A node used for protection of the ODUk and a receiving unit, a sending unit, a protected receiving unit and a protected sending unit on the node are selected. A connection between a receiving service unit and the protected sending unit with the same transmission direction on the node is established, or a connection between a sending service unit and the protected receiving unit with the same transmission direction on the node is established. Two virtual nodes are established on the node if the node is an intersection node, and connections between the receiving service unit and the protected sending unit, and between the sending service unit and the protected receiving unit are established respectively in each direction of both directions through one of the virtual nodes. | 04-21-2011 |
20110116788 | METHOD AND SYSTEM FOR SHARED PROTECTION IN WAVELENGTH DIVISION MULTIPLEXING LOOP NETWORK - The present invention discloses a method and a system for shared protection in WDM loop network. The WDM loop network comprises at least one node, and each node is divided into a multiplexing segment layer, a channel layer and a sub-wavelength layer. The method for shared protection comprises the following steps: A, the multiplexing segment layer, the channel layer and the sub-wavelength layer of each node are detected respectively; B, the detection point generates fault information when at least one of the multiplexing segment layer, the channel layer and the sub-wavelength layer goes wrong; and a controller of each node, according to the fault information, determines the protection control state of the present node and notifies the respective executor; wherein the protection control state includes service adding, service passing through, and service dropping; C, the executor of each node controls the corresponding node to switch to the protection control state determined in step B. The present invention realizes the shared protection in sub-wavelength level. | 05-19-2011 |
20110236012 | Transmission apparatus and method of changing transmission route - A transmission apparatus located on a communication transmission line including a ring transmission line and a bypass transmission line, the transmission apparatus includes: a judging unit which judges whether or not there is a change request for a transmission route of a signal to be transmitted via the bypass transmission line; and a changing unit which changes the transmission route such that the signal which is to be transmitted via the bypass transmission line is transmitted via at least one portion of the ring transmission line, when it is judged that there is the change request. | 09-29-2011 |
20110274425 | METHOD FOR PROVIDING PROTECTION IN AN OPTICAL COMMUNICATION NETWORK AGAINST CONNECTION FAILURES - The invention relates to an optical communication network ( | 11-10-2011 |
20120057863 | FREQUENCY-DEPENDENT I/Q-SIGNAL IMBALANCE CORRECTION FOR COHERENT OPTICAL TRANSCEIVERS - In one embodiment, a coherent optical receiver has a digital signal processor that processes one or more digital I/Q-signal pairs to recover data carried by a modulated optical signal in a manner that mitigates, based on calibration data retrieved from a memory or on appropriate performance measures and feedback mechanisms, the detrimental effects of frequency-dependent imbalances between the I and Q sub-channels of at least one of the I/Q channels of the receiver. In various embodiments, the calibration data can be generated and written into the memory at the fabrication facility or in situ while the receiver is being operated in a calibration mode. Alternatively or in addition, the calibration data can be generated and dynamically adjusted online during normal operation of the receiver. | 03-08-2012 |
20120099853 | Method and Device for Processing Failure of Multi-Span Working Channel in Ring Optical Transmission Network - The present invention discloses a method and device for processing an alarm in a ring optical transport network. The method comprises detecting alarm information in the ring network in real-time, and when generation of only an working ODUk alarm in the ring network is detected, performing a switching process of a 1+1 protection protocol on services carried on a working channel on which an alarm is generated; in the event that one working ODUk alarm has existed in the ring network, when generation of an alarm at a protection ODUk corresponding to the working ODUk on which the alarm has been generated is also detected, or when an optical multiplexed segment layer alarm is generated in the ring network, triggering a switching process of a channel shared protection protocol. The device comprises an alarm detection module and a switching triggering module. The present invention can perform the 1+1 | 04-26-2012 |
20120263452 | METHOD OF SWITCHING OPTICAL TRANSPORT NETWORK AND NODE DEVICE - A node device in an optical transport ring network including plural node devices connected in a ring form using plural optical transmission paths so that optical transport frames of a working line and a protection line are transmitted using the plural optical transmission paths, includes a control information transmitter, when a failure occurs in the optical transmission paths, transmitting the optical transport frame to an opposing node device as a transmission destination node in the optical transmission paths, the optical transport frame including switching control information; and a switcher receiving the optical transport frame including switching control information, the optical transport frame being transmitted to the node device as the transmission destination node, forming a loop back to fold a transmission path between the plural optical transmission paths, and switching the optical transmission path from the work line to the protection line. | 10-18-2012 |
20120275779 | Method, System and Device for Single-Fiber Bidirectional Ring Network Protection - A method, system and apparatus for single-fiber bidirectional ring network protection are disclosed in the present invention, wherein, one working path ring between various nodes in the single-fiber bidirectional ring network shares one sharing protection channel using a set wavelength, and when a fault occurs in a working path between certain two nodes, the method includes: controlling sharing protection apparatuses of a receiving end node and a transmitting end node of the failed working path to switch from a primary port to a corresponding standby port, controlling an intermediate node in the sharing protection channel corresponding to the working path to enable a standby port of the corresponding sharing protection apparatus, and establishing the sharing protection channel corresponding to the working path; transmitting a service signal carried in the failed working path through the newly established sharing protection channel. | 11-01-2012 |
20130051787 | OPTICAL TRANSMISSION DEVICE AND OPTICAL TRANSMISSION NETWORK SYSTEM - An optical transmission device in an optical transmission network including nodes, provided to one of the nodes, the optical transmission device including: a receiver to receive optical signals which have different wavelengths and are multiplexed, an optical detector to detect a strength of the optical signals, a switch to set switching control information including switching request information, each corresponding to one optical signal of the optical signals, and a transmitter to transmit the switching control information by an optical signal, wherein the switch sets, in information indicating a signal fail, the switching request information corresponding to the one optical signal in the switching control information based on the strength of one optical signal of the optical signals. | 02-28-2013 |
20130071104 | OPTICAL TRANSMISSION SYSTEM AND NOISE SUPPRESSION METHOD - A noise suppression method is used in an optical transmission system which includes node equipments transmitting a WDM optical signal. First node equipment drops a first optical signal from the WDM optical signal. The method includes: transmitting a failure signal that specifies the first optical signal from second node equipment to the first node equipment via a first route when the second node equipment arranged on the first route for transmitting the first optical signal to the first node equipment has detected a failure of the first optical signal; transmitting a shutoff signal that specifies the first optical signal from the first node equipment toward the second node equipment via the first route; and shutting off an optical output of a wavelength corresponding to the first optical signal in third node equipment that has relayed the failure signal and has received the shutoff signal. | 03-21-2013 |
20130279900 | PASSIVE OPTICAL NETWORK SYSTEM, METHOD FOR TRANSMITTING AND RECEIVING OPTICAL SIGNAL THEREOF, AND OPTICAL LINE TERMINAL - An optical line terminal (OLT) of a passive optical network (PON) detects a fault in an optical path configured as a single optical fiber core having an annular shape, divides the optical path into a right path and a left path having bi-directionality based on the fault position in which the fault has occurred, demultiplexes a plurality of downstream optical wavelength signals to be transmitted to at least one optical network terminal (ONT) of each group into an optical wavelength signal of the right path and an optical wavelength signal of the left path according to the position in which the fault has occurred, and outputs the same to at least one of the ONTs of each group. | 10-24-2013 |
20140255020 | Method, Apparatus, and System for Disaster Recovery of Optical Communication System - A method, an optical add-drop multiplexer branching unit, and a system for disaster recovery of an optical communication system are provided. The method for disaster recovery of an optical communication system using an optical add-drop multiplexer unit (OADM) includes: detecting a transmission link fault in an optical communication system; and when a transmission link fault is detected, switching the state of a link where the transmission link fault occurs from pass-through to loopback, so that an optical signal input from a non-faulty end of the link is looped back to the end for outputting. In this way, when a transmission link fault occurs in an optical communication system, the power level of a link where the transmission link fault occurs can be maintained by using the solutions in the embodiments of the present invention, thereby keeping transmission performance stable. | 09-11-2014 |
20150326310 | TRANSMISSION APPARATUS AND METHOD - A transmission apparatus includes: a storage unit to store a table in which a wavelength terminated by each of transmission apparatuses is associated with each of the transmission apparatuses; a transmission unit to transmit a message including failure information to other transmission apparatus when a failure occurs; a switch controller to determine whether its own transmission apparatus is a last transmission apparatus that terminates the wavelength among transmission apparatuses that are present on a path up to a link where the failure, based on the table, when receiving the message from other transmission apparatus, and to perform a control of switching a transmission direction of a signal having the wavelength when the switch controller determines that its own transmission apparatus is the last transmission apparatus to terminate the wavelength; and a switch to switch a transmission direction of the signal for each wavelength under a control of the switch controller. | 11-12-2015 |
20160134361 | GENERALIZED SERVICE PROTECTION SYSTEMS AND METHODS - Systems and methods for ring protection switching in a network based on selectively blocking and unblocking a port include forwarding traffic via the port over a data channel that utilizes a first service identifier, wherein the data channel is routed in the network along a closed loop; and selectively blocking and unblocking traffic on the port to provide the ring protection switching over the closed loop, wherein the selectively blocking and unblocking is performed based on a management channel that utilizes a second service identifier that is a different type from the first service identifier. | 05-12-2016 |
20190149896 | DATA CENTER PACKET OPTICAL TRANSPORT FAILURE PROTECTION | 05-16-2019 |
398004000 | Using a secondary ring or loop | 11 |
20090010640 | AUDIO/VIDEO SIGNAL REPEATER - An AV signal repeater includes a casing having multiple opening defined therein. A printed circuit board (PCB) is secured in the casing. The PCB has at least one signal connector and at least one terminal electrically mounted thereon. Each of the signal connector and the terminal is partially received in a corresponding one of the multiple openings. A signal transmission unit is electrically disposed on the PCB and electrically connected to the signal connector and the terminal for transmitting AV signal. | 01-08-2009 |
20090022489 | Optical Ring Networks Having Node-To-Node Optical Communication Channels For Carrying Data Traffic - Techniques, apparatus and systems for optical communications, including fiber ring networks with protection switching to maintain optical communications when an optical failure occurs and to automatically revert to normal operation when the optical failure is corrected, fiber ring networks that provide a circulating optical probe signal at an optical probe wavelength within the gain spectral range of optical amplifiers used in a fiber ring network to detect an optical failure, and fiber ring networks that support broadcast-and-select optical WDM signals carrying communication traffic to the optical ring nodes without regeneration at each optical ring node and one or more overlaid in-band node-to-node optical signals carrying communication traffic with regeneration at each node. | 01-22-2009 |
20090123146 | Packet Optical Channel Sharing Protection Method Device And System Thereof - The present invention discloses a method and system for group optical channel shared protection. In the invention, when a failure occurs, operations are performed on an optical wavelength group, and four actions are accomplished at the time of switching: switching the affected optical wavelength group on the working fiber to a backup fiber (Steer); switching the optical wavelength group whose destination node is the current node on the backup fiber to the working fiber (Copy); making the optical wavelength group whose destination node is not the current node on the backup fiber transparently pass through the current node (Pass Through); and blocking or stripping the backup wavelength group transferred on the backup fiber (Strip). In addition, the invention further discloses a plurality of node structures for realizing the above operations. | 05-14-2009 |
20090310960 | METHOD FOR MESH OPTICAL NETWORK SERVICE RESTORATION - This invention discloses a method for mesh restoration, which includes the steps of: a) reserving channel resource for restoration path in the link by which the path passes and assigning discriminator for each channel, and determining the associated signaling channels for transporting the discriminator; b) when detecting the work path fails, activating the restoration path of the work path according to the discriminator which is transported by the associated signaling channel and whose value corresponds to a restoration. Using the method of the invention, the problem in rapid mesh restoration can be solved, and the speed of mesh restoration is comparable to that of the ring network protection. | 12-17-2009 |
20100119223 | Optical Safety Implementation in Protection Switching Modules - Optical safety functions are incorporated into protection switching modules which maintain redundant pathways to avoid interruptions in optical network connections. The optical safety functions which lower optical power levels upon interruptions of optical connections are effectively combined with protection switching procedures which are also triggered by interruptions in optical network connections. The interoperation of protection and safety processes keep optical power levels below hazardous levels at system points which might be accessible to human operators. | 05-13-2010 |
20100232783 | OPTICAL CHANNEL INTELLIGENTLY SHARED PROTECTION RING - An optical ring network has one or more working wavelengths and multiple protection wavelengths adapted to support the working wavelength(s). Routing tables may be used in network nodes to assign traffic of a failed working wavelength to a protection wavelength. The protection technique may be applied to networks employing, for example, Dense Wave Division Multiplexing (DWDM). | 09-16-2010 |
20100239243 | PON RING SYSTEM, AND METHOD FOR REALIZING PRIMARY AND BACKUP LINK PROTECTION IN PON - A PON ring system and a method for realizing primary and backup link protection in a passive optical network (PON) are provided. A PON ring is established between at least two optical line terminations (OLTs) through at least two user side edge nodes or network side edge nodes. Each of the OLTs is coupled to any other OLT through the at least two edge nodes. Two links respectively in a clockwise direction and a counterclockwise direction exist in the PON ring, in which one link is a primary link and the other is a backup link. Node of the links adopt the transmission mode of “multiple sending and selective receiving”. Therefore, the present invention reduces the impact on the PON caused by single link failure in the network. | 09-23-2010 |
20120195588 | OPTICAL RING NETWORKS HAVING NODE-TO-NODE OPTICAL COMMUNICATION CHANNELS FOR CARRYING DATA TRAFFIC - Techniques, apparatus and systems for optical communications, including fiber ring networks with protection switching to maintain optical communications when an optical failure occurs and to automatically revert to normal operation when the optical failure is corrected, fiber ring networks that provide a circulating optical probe signal at an optical probe wavelength within the gain spectral range of optical amplifiers used in a fiber ring network to detect an optical failure, and fiber ring networks that support broadcast-and-select optical WDM signals carrying communication traffic to the optical ring nodes without regeneration at each optical ring node and one or more overlaid in-band node-to-node optical signals carrying communication traffic with regeneration at each node. | 08-02-2012 |
20130216215 | Optical Channel Intelligently Shared Protection Ring - An optical ring network has one or more working wavelengths and multiple protection wavelengths adapted to support the working wavelength(s). Routing tables may be used in network nodes to assign traffic of a failed working wavelength to a protection wavelength. The protection technique may be applied to networks employing, for example, Dense Wave Division Multiplexing (DWDM). | 08-22-2013 |
20140126898 | BI-DIRECTIONAL RING NETWORK HAVING MINIMUM SPARE BANDWIDTH ALLOCATION AND CORRESPONDING CONNECTION ADMISSION CONTROL - The present invention provides for a method for reserving spare bandwidth for a link in a communication network including a plurality of links. The method provides for monitoring the volume of traffic routed through each link of the communication network. A single link failure for each link is then simulated and the volume of traffic which would be rerouted through each link for maintaining communication and the volume of traffic removed from each link are determined for each simulated single link failure. The difference between the volume of traffic which would need to be rerouted through each link and the corresponding volume of traffic removed from each link is then computed, and a maximum difference value is determined for each link for all simulated single link failures. An amount of spare bandwidth equivalent to the determined maximum difference is then reserved for each link. | 05-08-2014 |
20160182147 | Protection Against Dual Failures For Resilient Two Layer Networks | 06-23-2016 |