摘要:
An L bit for notifying another router of whether a self-router belongs to a connection-oriented network is newly provided in the options field of a conventional OSPF packet and the OSPF packet, including L bit is transmitted to another router. In this way, each router belonging a network can automatically recognize a router belonging to a connection-oriented network by detecting L bit. Then, by generating a routing tree, a connection-oriented network device can be identified in the routing tree and mapping between a connection-oriented network and a connectionless network can be performed in an edge device.
摘要:
A packet flow control apparatus performing flow control of packets each having variable length, includes: a buffer memory for temporarily accumulating arrived packets until a sending time of each packet; a counter updated based on a rate determined in accordance with a packet length calculated by a counter value of the counter and limited flow of packets; a sending time determining section for determining the sending time of each packet based on the counter value and a present time; and a sending order control section for managing a sending order of each packet accumulated in the buffer memory, and for sending a read instruction of each packet to the buffer memory, based on the sending time determined by the sending time determining section.
摘要:
A method and apparatus for selecting paths to route incoming traffic through a data communication network, which is capable of effectively dispersing the traffic load to the selected paths on the network and effectively optimizing the use of network resources. In a communication network, a plurality of label switched paths between an ingress node and an egress node are provided. Incoming traffic at the ingress node is labeled and delivered through the network to the egress node. In a method and apparatus for selecting paths to route the incoming traffic through the network, a plurality of forwarding equivalent class elements (FEC) of the incoming traffic at the ingress node are allocated for the plurality of label switched paths. The labeled traffic is delivered on the plurality of label switched paths on an FEC-element basis so as to route the labeled traffic through the network to the egress node. The traffic load on the respective label switched paths can be effectively dispersed and the sequence of data packets, sent by the same terminal, may be maintained.
摘要:
In an ATM switching system responsive to a call setup request from each of B-ISDN terminals, a band for an accepted call is estimated in accordance with fuzzy decision on the basis of the fact that the network traffic characteristics can be determined empirically. Therefore, it is possible to estimate the band without any complicated band estimation calculations, improve the call acceptance processing response speed, and further improve the availability efficiency of the network transmission line. In the consequents of the fuzzy rules in particular, the respective band estimation values are represented by the respective input functions, or particularly by the linear couplings coupled by predetermined linear parameters of respective Inputs, thus improving the descriptive capacity of the rules.
摘要:
A video quality monitoring method includes a distribution server measuring first video quality index values according to a full-reference method by comparing a video, distributed from the distribution server to a client through a network, with a degraded video, generated by causing multiple scenarios of quality degradation due to the network in the video in a pseudo manner, creating characteristic data of first quality degradation values, obtained by causing the quality degradation to vary with the scenarios at regular intervals, and the first video quality index values corresponding to the respective scenarios, and transmitting the characteristic data to the client; and the client measuring a second quality degradation value in the video distributed through the network, and calculating a second video quality index value, equivalent to a value according to the full-reference method, of the distributed video from the measured second quality degradation value and the characteristic data.
摘要:
The present invention relates to distributing the load between the set routes among a plurality of routes between a communication apparatus which serves as a start point to another communication apparatus which serves as an end point. An apparatus provided in a router in a network collects traffic characteristics of transmission paths connected to the router, notifies other routers of the collected traffic characteristics, calculates load based on the collected traffic characteristics, decides based on the calculated load information whether or not a transmission path should be added or deleted, and equalizes the load among the plurality of transmission paths.
摘要:
A transmission apparatus which can enhance the transmission quality and reliability by establishing a recovery-path efficiently at a high speed for failure circumvention. A recovery-path request message control block generates, sends, and receives a recovery-path request message containing failure location information and recovery-path setup information. A label assignment message control block generates, sends, and receives a label assignment message. A setup label information generation block generates setup label information. A recovery-path label table management block constructs and manages a recovery-path label table. A failure detection block detects the location of a failure. A failure notification message transfer block transfers a failure notification message containing failure location information. A recovery-path establishment block establishes a recovery-path by comparing failure location information contained in a failure notification message and failure location information contained in a recovery-path label table and by selecting setup label information corresponding to matching failure location information.
摘要:
In an ATM switching system, an ABR service is implemented with a specific ABR control capability. A subscriber line processing device includes calculating a turnaround delay time of a cell, based on a period during which the cell doubles back at a terminal. A switch or a demultiplexer capable of detecting congestion. A rate calculator calculates a transmission rate corresponding to an output channel, and writes the calculated rate to the cell. A rate changer changes the transmission rate according to congestion. The rate changer counts the number of communicating connections. Then the number of communicating connections which should exist in a certain predetermined period is estimated based on the counted number of communicating connections. A coefficient is determined based on the estimated number of communicating connections and an actual number of communicating connections, and a next estimated value is estimated using the coefficient.
摘要:
Specific ABR control capability for implementing an ABR service in an ATM switching system. A subscriber line processing device has a capability for calculating a turnaround delay time of a cell, based on a period during which the cell loops back at a terminal and returns. A switch or demultiplexer has a capability for detecting congestion. A rate calculator calculates a transmission rate corresponding to an output channel, and writes the calculated rate to the cell. A rate changer suitably changes the transmission rate according to the degree of occurrence of congestion. Additionally, the rate changer counts the number of communicating connections. At this time, the number of communicating connections which should exist in a certain predetermined period is estimated based on the counted number of communicating connections, which is counted in a period shorter than the predetermined period according to a predetermined method. Additionally, a coefficient is determined based on the number of communicating connections so estimated and an actual number of communicating connections, and a next estimated value is estimated to be a more suitable value using the coefficient.
摘要:
A call admission control system in an asynchronous transfer mode exchange includes a unit for describing attribute parameters of a call from the subscriber terminal; a unit for calculating, based on the attribute parameters, the average and the dispersion of the traffic speeds of the call; a unit for managing data of the average and the dispersion on each output route and data relating to each subscriber; and a unit for calculating the total average and the total dispersion of the data speeds on the selected output route; and a unit for calculating prediction values of cell abandon rate and end-to-end delay based on the average and the dispersion on the selected output route calculated by the total average and dispersion calculating unit, and for comparing the prediction values with the required service quality of cell discard rate and end-to-end delay, for determining whether or not the requesting call may be connected.