2222 results about "Loop network" patented technology

A network adapter for a synchronous logical ring network operates on existing physical twisted-pair telephone topologies. Information propagates around the logical ring, reaching every device on each revolution around the network. Network devices are full-duplex, transmitting and receiving information on every clock cycle. Network devices arbitrate to be elected the network clock device. By synchronizing all network devices to a single reference clock, and providing fixed frames of information propagating around the network at consistent time intervals, the logical ring network ensures that information propagates from one device to another at consistent time intervals. The fixed-length frames are divided into two independent streams: a data stream for the distribution of real-time continuous digital media streams; and a system command stream for the distribution of system commands.

A method of running a target device in a hardware-in-the-loop network simulation via a host computer may include launching a network application on a host computer each having a protocol stack and a network device connected to a simulated network of target devices, interposing, on the host computer, a target device interface and adaptor between the protocol stack and the network device and transferring data and control information between the network application and the target device via the network device, whereby the target device runs on the host computer as if the target device were running directly on a host computer having a network device directly compatible with the target device.

This invention discloses a ring network and a method for implementing the service thereof. The ring network includes multiple nodes in a same logic layer for accessing a service to the ring network or receiving a service from the ring network; two virtual channels of reverse directions, which connect the adjacent nodes and are utilized to bear and adapt service data; a physical link, which is utilized to bear the service data adapted to the virtual channel. The method includes the steps of configuring virtual channels at the nodes to form an eastward and westward bidirectional ring network; establishing service Label Switching Path schedules at the nodes; determining a service sink node according to the Label Switching Path schedule at a service source node; dispatching services up to the ring network according to a predetermined algorithm; multiplexing the services of different nodes in a same virtual channel for transmission in the way of Label Switching Path; dispatching the services down the ring network at the service sink node.

The invention discloses an automatic test system for an intelligent substation spacing apparatus in the technical field of power systems, comprising: a test system control module and a test terminal connected with the same. In the system, signal authentication and input and output of test data are finished by establishing an input/output signal system at outside of the apparatus; signal pair point test of an apparatus station control layer is finished by a simulated MMS (Multimedia Messaging Service), analog input of the input signal of the apparatus is finished by a Goose/SMV process layer simulator, and behavior result of the apparatus is judged by monitoring a test closed loop network message; and different target test data object test cases are configured, the test data is input via the simulator so as to monitor behavior and response of the apparatus.

Disclosed is a method for dynamically and losslessly adjusting bandwidth of an embedded Resilient Packet Ring (RPR) ring network, in which dynamic and lossless bandwidth adjustment for an RPR ring network embedded in a Synchronous Digital Hierarchy (SDH)/Synchronous Optical Network (SONET) can be realized through adding a Link Capacity Adjustment Scheme (LCAS) system in the SDH/SONET processing layer. When it is required to increase ring network bandwidth, the bandwidth of the link section between sites on the SDH/SONET processing layer is first increased. Then the LCAS system in the SDH/SONET processing layer is started, and the actual bandwidth of the link on the SDH/SONET processing layer is increased losslessly with the LCAS system. Finally the bandwidth of the ring network on the RPR processing layer is increased. When it is required to decrease ring network bandwidth, the bandwidth of the ring network on the RPR processing layer is first decreased. Then the LCAS system in the SDH/SONET processing layer is started, and the actual bandwidth of the link on the SDH/SONET processing layer is decreased losslessly with the LCAS system. Finally the bandwidth of the link section between sites on the SDH/SONET processing layer is decreased. With the disclosed method, dynamic and lossless bandwidth adjustment for an embedded RPR ring network in SDH/SONET can be realized.

Among networks of ring configuration, the dual ring topology with source steering or wrapping capabilities offers numerous advantages over a single ring topology. In the management of a ring network, problems consist in making sure that every node in the ring is aware of the current ring topology. If, however, two or more links fail even in a dual ring network, the propagation of discovery packets is not guaranteed. A new topology discovery technique is disclosed. In accordance with one aspect of the invention, the algorithm uses only one discovery packet format and a set of timers for a variety of actions to be performed at each node on the ring. The protocol finds valuable applications in RPR and many similar network architectures.

A ring-mesh network architecture is provided for increasing the working/protection bandwidth ratio (W/PBR) of transport networks. The ring-mesh network has mesh connections between some nodes, the traffic on the mesh connections being unprotected. This increases the W/PBR from the current 1:2 value to (n−2)/(n−1), where n is the number of nodes, (n−1) is the number of connections on each node and (n−2) is the number of working connections on each node for one direction of traffic. Ring-mesh networks with add/drop multiplexers in the mesh connection are also provided.

A method and system for implementing weighted fair flow control on a metropolitan area network. Weighted fair flow control is implemented using a plurality of metro packet switches (MPS), each including a respective plurality of virtual queues and a respective plurality of per flow queues. Each MPS accepts data from a respective plurality of local input flows. Each local input flow has a respective quality of service (QoS) associated therewith. The data of the local input flows are queued using the per flow queues, with each input flow having its respective per flow queue. Each virtual queue maintains a track of the flow rate of its respective local input flow. Data is transmitted from the local input flows of each MPS across a communications channel of the network and the bandwidth of the communications channel is allocated in accordance with the QoS of each local input flow. The QoS is used to determine the rate of transmission of the local input flow from the per flow queue to the communications channel. This implements an efficient weighted bandwidth utilization of the communications channel. Among the plurality of MPS, bandwidth of the communications channel is allocated by throttling the rate at which data is transmitted from an upstream MPS with respect to the rate at which data is transmitted from a downstream MPS, thereby implementing a weighted fair bandwidth utilization of the communications channel.

In node devices composing a ring network connected to another network with a redundant node device, a topology table includes redundancy information of the redundant node device, a transmitter transmits topology information and the redundancy information of the node devices themselves, a topology table preparing portion prepares a topology table based on redundancy information and topology information received from the redundant node device, and topology information received from the other node device, and a packet distributor distributes a packet received over the ring network based on the topology table.

The invention discloses a pharmaceutical product manufacturing execution system and method. The method includes connecting a manufacturing execution system function server and a manufacturing execution system database server to an upper-level management terminal through an industrial loop network; allowing the manufacturing execution system function server to perform data exchange with a production management terminal through the industrial loop network; allowing the production management terminal to connect to a bottom procedure controller through the industrial loop network; allowing the production management terminal to receive a production planning instruction from the upper-level management terminal, divide the production planning instruction into a production instruction and a material list and transmit the production instruction to the bottom procedure controller, and allowing the bottom procedure controller to control corresponded production procedures and acquire staff producing operation information and corresponded equipment information. The method has the advantages that the corresponded material is encoded correspondingly and respectively, the workshop producing material data management and tracking are implemented, the statistical graph and report support is provided, and the material management is simplified.

The invention discloses an automatic system fault handling method of a distribution network containing a plurality of distributed power supplies. The output mode of traditional distribution network protection and feeder automation cannot meet the requirement on distribution network fault handling when a system containing a plurality of distributed power supplies works, and must be improved and perfected. The method establishes an independent fault information transmission channel with optical fiber Ethernet equipment through an SOCKET connection method on the basis of using light Ethernet communication; adopts a peer-to-peer communication mechanism, realizes the peer-to-peer communication between the fault information of terminal devices, and effectively solves the problems of production, feeder automation and the like under the circumstance of a looped network. The automatic system fault handling method of the distribution network containing a plurality of distributed power supplies has very good sensitivity, selectivity and quickness.

The invention discloses a method, network equipment and a system for data transmission, which can be applied to star and tree networks and dual-homing looped networks. The method comprises that: in a downlink direction, a master node transmits a downlink service signal to a slave node in a mode of optical layer broadcast, wherein a continuous optical signal which carries the downlink service signal also comprises an uplink bandwidth map; the slave node and the master node are connected by an OB (Optical Burst optical burst) channel; and the slave node adapts an uplink service signal to different OBUs for performing photoelectric conversion and transmitting a burst optical signal in a burst mode according to the number and serial number of the OBUs distributed to nodes in the uplink bandwidth map transmitted by the master node. The method, equipment and system easily realize burst amplification and high-speed burst receiving so as to better meet the requirements on long distance, large bandwidth and high transmission quality.

The embodiment of the invention provides a multi-core DSP (digital signal processor) system-on-chip and a data transmission method. The system comprises a main processor, multiple slave processors and an external memorizer, wherein each main processor and slave processor respectively comprise a processor core, a memorizer-on-chip and a direct memory access (DMA) controller, the main processor controls and accesses the external memorizer through an I/O (input/output) controller, data exchange can be realized among processors through an internet-on-chip, wherein the internet-on-chip is composed of a star network, a loop network and a serial network. The internet-on-chip provided by the embodiment of the invention combines the star network, the loop network and the serial network, so that the internet-on-chip can not only provide streaming data transmission with high bandwidth, but also provide short message transfer with low delay. Besides, the embodiment of the invention simplifies the access arbitration of the external memorizer through the software control of the main processor, reduces the synchronous operations among the multi-core processors through the network data buffer and lowers the complexity of the program design of the multi-core processors.

A method in a network device configured in a true ring network where the network device has a first port and a second port connected to the true ring network and a third port connected to a processor including: connecting the network device to transmit data packets in a single direction around the true ring network including an ingress port and an egress port; enabling ingress tag VLAN filtering on the ingress port only; configuring a VLAN table in the network device to terminate an incoming data packet when a VID tag (VLAN identifier tag) of the incoming data packet matches the local VID tag of the network device; and configuring the VLAN table in the network device to accept the incoming data packet when the VID tag of the incoming data packet does not match the local VID tag of the network device.

The invention is used in ring networks crossed each other (N is a natural number and is greater than or equal 2); wherein, the one is main ring and the N-1 are sub-rings; each ring network only has a main node. The method comprises: when the assistant edge node detects that protocol message channel of sub-ring on the main ring is interrupted, after it receives the notice from the assistant edge node through the edge port, the edge node blocks the edge port, and informs the sub-ring that the edge port of main node is blocked, and indicates the main node of sub-ring to open the standby port. The invention also opens a system and a network apparatus thereof.

The invention discloses a method for recovering networks in a ring network. Ethernet switch equipment enters a communication status after an initial configuration and precise time synchronization based on an IEEE 1588 protocol. Each equipment according to the configuration of the network sends out time-sharing equipment statement messages and link circuit checking messages. The link circuit checking messages are sent by a multicast address in two ways; if a port of equipment receives no link checking messages of a connected port after the time out, then a network trouble can be determined and link circuit alarm messages are sent by the multicast address in two ways for alarming. The rest equipments in the ring network after receiving the link circuit alarm message, then empty an FDB list and utilize a backup link circuit to restart path learning. By adopting the method of the invention, any communication link circuit failure in the ring network can be quickly detected and correspondingly processed, thereby meeting the availability requirements of Ethernet communication by the industrial automatic field.

The disclosed network includes two rings, wherein a first ring transmits data in a clockwise direction, and the other ring transmits data in a counterclockwise direction. The traffic is removed from the ring by the destination node. During normal operations (i.e., all spans operational), data between nodes can flow on either ring. Thus, both rings are fully utilized during normal operations. The nodes periodically test the bit error rate of the links (or the error rate is constantly calculated) to detect a fault in one of the links. The detection of such a fault sends a broadcast signal to all nodes to reconfigure a routing table within the node so as to identify the optimum routing of source traffic to the destination node after the fault.

A master node transmits a probe packet for checking a condition of a network in a ring in both directions thereof to detect the occurrence of a fault on the ring. A slave node increments a hop count included in the received probe packet, transmits it to an adjacent node configuring the ring, and transmits a hop count report packet to the master node. The master node detects a fault on the ring based upon a fact that the master node does not receive the probe packet transmitted by itself. Further, the master node detects the occurrence of multiple faults and the recovery of at least one of the multiple faults based upon the sum of maximum values of hop counts in the hop count report packets received from both directions of the ring and transmits a packet for prompting the update of the database for packet transfer.

A system for controlling packet forwarding through a dual-homed connection between first and second network domains, the dual-homed connection including two peer nodes connected to the first and second network domains. A sub-ring network is instantiated in the first network domain, and includes at least two nodes connected in a linear topology between a pair of end-nodes. Each end-node corresponds with a respective one of the peer nodes. A virtual link through the second network domain for conveys traffic of the sub-ring network between the peer nodes, and closes the sub-ring network to define a ring topology. Each of the nodes of the sub-ring network is controlled to forward packets of the sub-ring network in accordance with a ring network routing scheme.

The invention discloses a stand-by power supply automatic switch method for a multi-stage series connection power supply network, wherein the power supply network adopts ring network power supply, and a main power supply mode is that two external power source inlet wires carry left and right buses of a plurality of substations respectively. When a ring network line breaks down or a bus breaks down, a corresponding protective device eliminates fault and sends a switch connection signal through fiber transmission to a protective device of a next stage non switch substation simultaneously where the fault line locates, and sends a starting signal to a bus coupler stand-by power supply automatic switch device where next stage non switch locates. The stand-by power supply automatic switch device detects the starting signal, combined with a self voltage criterion, a remote signal state criterion and the like, determines whether to switch on the stand-by power supply or not simultaneously. Because a stand-by power supply automatic switch of a bus coupler switch of the next stage non switch substation where the fault line locates can not detect the starting signal, the stand-by power supply automatic switch performs no action. According to the invention, a problem that traditional stand-by power supply automatic switch function is lack of selectivity in ring network power supply systemapplication is solved.