Abstract: Network traffic may be estimated using samples of network activities to identify traffic parameters. A model of the network may be generated using the traffic parameters, and the model can be used to simulate the network using a modified set of parameters. Network traffic may be managed using the results of the simulation. Network traffic can also be managed by intercepting and modifying a control message on a peer-to-peer network.

Abstract: A system includes a communication network having any number of separately addressable elements. An analysis device can test packet data paths between these elements by eliciting particular traffic patterns. For example, the analysis device may elicit similar traffic patterns in both forward and reverse communications with a remote element and analyze these communications to detect network misconfigurations.

Abstract: Network traffic may be estimated using samples of network activities to identify traffic parameters. A model of the network may be generated using the traffic parameters, and the model can be used to simulate the network using a modified set of parameters. Network traffic may be managed using the results of the simulation. Network traffic can also be managed by intercepting and modifying a control message on a peer-to-peer network.

Abstract: A system includes a communication network having any number of separately addressable elements. An analysis device can test packet data paths between these elements by eliciting particular traffic patterns. For example, the analysis device may elicit similar traffic patterns in both forward and reverse communications with a remote element and analyze these communications to detect network misconfigurations.

Abstract: A method and apparatus for selecting failure protection paths in a WDM network. The method exploits wavelength reservation sharing potentials presented by non-concurrent failure events on a plurality of links sharing a link in a protection path. Light-weight aggregated link metrics termed “buckets” are used to track wavelength reservations for protection paths on individual links in the network. These buckets are then used to construct protection paths with minimized wavelength consumption. The method is employed on individual networking devices in a distributed manner or is used by a centralized network management system to allocate protection paths.

Abstract: A method and apparatus for selecting failure protection paths in a WDM network. The method exploits wavelength reservation sharing potentials presented by non-concurrent failure events on a plurality of links sharing a link in a protection path. Light-weight aggregated link metrics termed “buckets” are used to track wavelength reservations for protection paths on individual links in the network. These buckets are then used to construct protection paths with minimized wavelength consumption. The method is employed on individual networking devices in a distributed manner or is used by a centralized network management system to allocate protection paths.

Abstract: This invention provides a network management system with a route predicted beforehand through which a control IP packet is to be transmitted, and while setting up permission of control in a communication apparatus that checks permission of control, if the control IP packet is to be permitted, when the communication apparatus which received the control IP packet checks the permission of control with the network management system, permission of control is set up in other communication apparatuses on the predicted route over which the control IP packet is to be transmitted. For this reason, the number of checking messages of the control permission from the communication apparatuses which received the control IP packet can be reduced, while the amount of processing, such as a database search in a network management system and updating, can be reduced, and control permission to a control IP packet can be checked speedily.

Abstract: A method of generating access-control lists executable by a system and derived from access-control rules supplied for insuring security of an operation system is presented.

Abstract: A communication network comprised of communication paths of server layers formed hierarchically by communication paths of client layers, wherein the state of control of the communication paths of a layer being controlled is independently managed in terms of both (i) an administrative state and (ii) a subordinate state indicating influence from communication paths of a server layer, the administrative state of the communication paths of the layer being controlled is changed according to the control for setting and releasing the communication paths, and the subordinate state of the communication paths of a client layer influenced by the change of the administrative state of the communication paths is changed accordingly. At this time, when a subordinate state has already been influenced by a state of control of the communication paths of a server layer, the processing for management is terminated.

Abstract: A detour path determination method wherein each node on a determined detour path stores in advance first and second nodes upstream of each node as well as an identifier(s) of a packet directional path(s); a number of an identifier(s) of a packet directional path(s) required for switching in each link extending from a downstream node one node downstream of each node on the detour path are set for respective nodes on the detour path beginning from the terminal node upstream; the identifier(s) of the packet directional path(s) set as above, and an identifier(s) of a corresponding packet directional path(s) at a start node of the detour path, are sent to a node one node upstream of the above each node; the start node updates a identification data table at the node, by an identifier(s) of a packet directional path(s) set downstream of the start node based on the corresponding identifier(s) of packet directional path(s) at a start node of the detour path, when the start node receives the above identifier(s) (FIG.

Abstract: A dynamic database structuring method includes the steps of (a) clustering transition probabilities among transactions by on-line, (b) forming a hyper graph representing the transition probabilities of the transactions clustered in the step (a) using weighting, (c) partitioning the hyper graph to obtain clustering information related to objects or records to be stored in a storage, and (d) reorganizing a database by rearranging data in the storage by on-line using the clustering information obtained in the step (c), thereby restructuring the database dynamically.

Abstract: A method of controlling a telecommunication network management is disclosed. By the method, a managing subject of a telecommunication network carries out a management sequence for management information of the telecommunication network in an agent subject. The method comprises the steps of (a) locating a cache storing the management information in the managing subject; and (b) partitioning attributes of the management information into attribute classes corresponding to demands for cache coherency. In the method, the managing subject carries out the management sequence with a higher speed by accessing the cache, and manages the cache for each attribute class efficiently.

Abstract: A path switching system and method for a multiple-node ATM network, in which a plurality of paths can be simultaneously switched preserving proper correspondence thereof. A key choosing unit provided in a node chooses first and second sorting keys out of the virtual paths between the nodes, based on a first and second path information stored in a path information memory unit. Two nodes located at both ends of the route failed due to trouble in the ATM network select a first pair of isolated virtual paths having the first sorting key, which were formerly connected to the failed route, and connect them to a first bypass route. The two nodes then connect in a similar way a second pair of isolated virtual paths both having the second sorting key to a second bypass route.

Abstract: The upper and lower bounds of the probability distributions of the number of arrivals at given arrival rates and the upper and lower bounds of the distributions of the arrival rates of each call class are prestored in memory, and by referencing such prestored values, the distributions of the arrival rate and the number of arrivals are obtained (step 104), then, the upper and lower bounds of the resulting cell length distribution are calculated to obtain safe-side evaluation values of QOS parameters (step 106). Based on the obtained QOS parameters, admission or rejection of a call is determined (step 108). Using this method, a function defining the upper bound of the probability distribution of the cell flow rate at the outgoing line side can also be obtained, from which a threshold value is calculated, and abnormality in the cell flow rate is judged on the basis of the threshold value.

Abstract: A cell loss ratio calculating method is a method of calculating a cell loss ratio of a buffer for storing call cells from a plurality of traffic sources and comprises a distribution expressing step, a number-of-average-arrivals expressing step, an average path calculating step and a cell loss ratio calculating step. In the distribution expressing step, a distribution of the number of cells accumulated within a time for which the cell passes the buffer is expressed by use of a Poisson distribution on an assured side. In the number-of-average-arrivals expressing step, the number-of-cells distribution is expressed with parameters representing a number of average arrivals of the Poisson distribution. In average path calculating step, an average path is calculated with respect to time-variations of a cell arrival ratio and a distribution of the cell arrival ratio.

Abstract: A communication system using a network route establishing technique for a network having a plurality of nodes connected through links, in which a route search message is delivered simultaneously in a plurality of directions from a sender node through a network route to a destination node, and a confirmation is delivered from the destination through the network route back to the sender node, and accordingly, a network route is established. The communication system includes a device for detecting, at a node through which a search message is to be transmitted, a possibility of a transmission of the search message beyond the node, a device for delivering a cancel message in the direction from which the search message has been transmitted, and a device for releasing the network route engaged by the search message, based on the delivered cancel message.

Abstract: A probability transition matrix S.sub.t is formulated that expresses a multiplexing process which includes nested threshold priority control and classified priority control. A state equation using the matrix S.sub.t is solved by substituting therein upper and lower bounds of a probability distribution of a cell arrival count a.sub.t in an average time series, to calculate a probability distribution of a cell length in a buffer. From the thus calculated cell length probability distribution, the QOS is evaluated on a priority class basis. Based on the QOS evaluation, optimization of call admission control and priority control is accomplished.

Abstract: A packet directional path identifier transfer system contains on the transmission side thereof, a means 2 of converting packet directional path identifier data into bit map information in which an address of each bit corresponds to a packet directional path identifier. The system contains on the reception side thereof, a means 5 for inversely converting the bit map information of the packet directional path identifier data to the packet directional path identifier data.

Abstract: A method for restoring a communication failure in a network comprises the steps of providing a predetermined order for selection of the links included in the network, searching for an alternative communication path upon a failure in communication occurring in the network, producing, at a first arbitrary node included in the alternative communication path, a first path setup message containing at least information about the number of the paths to be selected in a first link extending from the first node for setting up the alternative communication path, and an identification code of the path that is to be selected at first in the first link for establishing the alternative communication path, transmitting the first path setup message to a second node also included in the alternative communication path and connected to the first node by a second link, for affecting a setup of the connection therein.

Abstract: A system for searching for alternative routes in a network at the time of a failure in a node or link which executes a stage for initiation of failure restoration processing which starts up failure restoration processing in accordance with various types of messages when a failure occurs at a link or node, a stage for processing a restoration message for searching for an alternative route, a stage for processing an acknowledgment message for reserving an alternative route, a stage for processing a cancellation message for cancelling reservation of an alternative route, a stage for processing a confirmation message for confirming a reserved alternative route and making a switching of cross-connect equipment, a stage for processing a cross-connection completion message for notifying the completion of switching of the cross-connect equipment to the nodes, a stage for processing a cross-connection acknowledgment message for confirming the completion of switching of all of the cross-connect equipment on the alterna