Nec Corporation

Juniper Networks, Inc.

Yasuhiro Miyao

Motoo Nishihara

Kenshin Yamada

Masahiko Honda

Makoto Fujinami

Tatsuya Shiragaki

Toshiya Aramaki

Yoshiyuki Yamada

Akira Arutaki

An index calculation unit calculates a periodicity determination index for determining the presence of periodicity on the basis of the differential between each segment of the frequency distribution of input numerical data and a frequency distribution in accordance with a baseline distribution provided ahead of time. A determination unit uses the periodicity determination index calculated by the index calculation unit to determine the presence of periodicity including one or more periodic components present in the numerical data.

Periodicity detection method, periodicity detection device, and periodicity detection program

Data transfer with high throughput is enabled between servers. When in a set of sites each having a usable network operation unit, a new site is added or an existing site withdraws, designing is executed for determining a combination of the network operation units each one of which is to be used in each added or withdrawn site such that at least a site which transmits or receives data becomes reachable based on a connection relationship between each paired network operation units added or withdrawn, and when a combination of the network operation units is determined in the designing, the network operation unit determined is considered as a network operation unit to be newly used in each site.

Network operation system, network operation method and network operation program

Data transfer with high throughput is enabled between servers. With respect to a candidate of a network operation unit applied at least one to each site of a plurality of sites forming a network, a combination of the network operation units each one of which is to be used by each site is determined such that all the sites become reachable based on a connection relationship applied to each pair of the candidates of the network operation units between different sites.

Network designing system, network designing method, data transfer path determination method and network designing program

A device for reproducing a content having at least one reproduction start time predetermined, includes: a non-real time receiver for receiving a content in non-real time; a scheduler for scheduling reception of a content whose delivery method is non-real time delivery by the non-real time receiver based on a current time and a reproduction start time of the content; a content storage section for storing at least one content received by the non-real time receiver; and a reproduction controller for inhibiting reproduction of a content stored in the content storage section before the reproduction start time of the content.

Device and method for preventing unauthorized reproduction of content

A datagram relaying apparatus includes a plurality of protocol terminating units, and a destination determining processor. The destination determining processor includes a path selecting section which determines a transfer destination route for a stream of packets received from any of the protocol terminating units. The path selecting section determines whether or not transfer of the received stream of packets to the transfer destination route is in an inhibition state, and selects another transfer destination route when the transfer of the packet to the transfer destination route is in the inhibition state.

Datagram relaying apparatus with load distributing function

A network designing method is provided that decides the slot allocation in a bi-directional ring system through which paths are routed, at minimum total costs for ring systems and for cross connect (XC) connecting them. Routes for a ring candidate and a node base path candidate are created based on connection information regarding nodes and spans and based on demand pairs and hubs (step A ). Thus, an integer programming problem is created and solved (step A ). The solved results are used to decide the number of ring candidates to be installed in bi- and uni-directional ring systems, nodes to which ADMs are installed in each ring system, node base path capacities, and slot numbers allocated to channels routing a bi-directional ring system (step A ).

Network designing method and recording medium on which the control program is recorded

A multilayer ATM communication equipment includes a port VPI-VCI table, an ATM switch, an MAC frame forming section, a flow VPI-VCI table, a flow identification section, a port MAC address table, and an MAC switch section. The port VPI-VCI table stores transfer route information and input/output port information. The ATM switch transfers the ATM cell from the output port corresponding to the output port information on the basis of the transfer route information and the input port number. The MAC frame forming section forms an MAC frame on the basis of the transfer route information. The flow VPI-VCI table stores flow information and transfer output information. The flow identification section transfers the MAC frame on the basis of the transfer output information. The port MAC address table stores the destination information of the MAC frame and transfer output information. When transfer output information is stored in the port MAC address table, the MAC switch section transfers the MAC frame on the basis of the transfer output information. Otherwise, the MAC switch section assigns a new input port, notifies a transmission-side switch of the flow information and the input port, sets a shortcut path, and transfers the MAC frame from the notified output port.

Multilayer ATM communication equipment

When a virtual channel handler terminating a virtual path tries to expand its capacity by signalling and the trial has failed, the virtual channel handler delivers an expansion request to a reconstruction server. Supplied with the expansion request, the server delivers a reduction request to each of virtual channel handlers terminating other virtual paths passing the same physical links as the virtual path. Supplied with the reduction request, each of the virtual channel handlers calculates a required VP capacity value, reduces by signalling current capacity to the required VP capacity thus calculated, and delivers to the server a reduction response including a reduction value. The server is responsive to the reduction response and delivers an expansion response to the virtual channel handler with a minimum reduction value as an expandable value. The virtual channel handler is responsive to the expansion response and calculates new VP capacity which is a sum of the current capacity and the expandable value to expand the VP capacity by signalling.

ATM network enabling quick and reliable reconstruction by distributing a series of steps to communication nodes to follow a time-varying traffic load

A network design method allowing to build, at a low cost, a network which operates properly even upon failure occurs or load variation, satisfying a capacity required by a demand pair. The method solves an integer programming problem containing an objective function that minimizes the cost of link capacity. The problem receives information on a network topology, failure patterns indicating where a failure occurred, a demand capacity of a current path of a demand pair in each time zone and direction, a demand capacity of a standby path to be used when a failure occurs on the current path, and combination candidates of the current path and the standby path. The problem contains indicator variables indicating whether to use a combination of a current path and a standby path connecting the ends of each demand pair in each time zone and variables indicating the capacity to be assigned to each link. The method solves the problem under a constraint that the total of the indicator values for the request pair must be 1 and under a constraint that either the current path or the standby path is used for each time zone, each state, and each request pair and that the total of the demand capacities of all the paths going through a link ought not to exceed the capacity of the link.

Network design method

A network server includes LAN terminating units, an ATM terminating unit, a data transfer unit, a multiple identifier check section, and a connection determination section. The LAN terminating units are connected to LAN terminals constituting virtual LAN segments and terminate protocols on the LAN MAC sublayer. The ATM terminating unit is connected to an ATM network and terminates the AAL and the ATM protocol. The data transfer unit transfers received data to one of the LAN terminating units and the ATM terminating unit in correspondence with the destination MAC address obtained from data received by the LAN terminating units and the ATM terminating unit. The multiple identifier check section checks at least the Ethernet type in the SNAP of the received data. When the data is transferred from the data transfer unit to the ATM terminating unit, the connection determination section determines an ATM connection to which the data is to be transmitted, on the basis of a set of the destination MAC address and the destination IP subnetwork address, obtained from the received data, and an identifier including at least the Ethernet type detected by the multiple identifier check section, and notifies the ATM terminating unit of the determined ATM connection.

Network server

ATM switching apparatus having a capability of switching ATM cells without providing a conversion table for converting routing information in the ATM switch unit and channel identification information of VPI and VCI. is When a call set-up request is originated from a terminal 1a, a call control unit 13 designates, as a channel identification information, an output port number P.sub.o1n of a switch unit 12 corresponding to a terminal 1n and a channel identifier LCN of a logical channel for coupling a terminal 1a with a terminal 1n, and an output port number P.sub.o1a corresponding to the terminal 1a and the LCN to the terminal 1n. When a cell is transmitted from the terminal 1a, the P.sub.o1n and LCN are stored into a header portion of the cell. In a line terminating unit 11a, an input port number P.sub.I1a corresponding to the terminal 1a is added to the header portion, and the cell is switched in the switching unit 12 by information of the P.sub.o1n and the LCN. In a line terminating unit 11n, the P.sub.o1a is erased from the header portion of the cell, and the input port number P.sub.I1a and the LCN are formed for channel identification information to be supplied to the receiving side of terminal 1a.

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Tokyo, Japan

Yasuhiro Miyao