Abstract: There is provided a measuring apparatus for acquiring packets being transmitted and received within a packet network and measuring communication quality on the basis of the acquired packets, the apparatus including a part that extracts packets acquired within one of given sampling periods, each sampling period set intermittently, and a part that measures communication quality on the basis of the packets acquired within the sampling period.

Abstract: A packet delay characteristic measuring apparatus that can accurately only measure a delay in a network even if a delay may occur also in a device that receives packets. The apparatus includes: a sending section for periodically sending out test packets each including sending time information to the network; a branching section for handing over the test packets flowing from the network to each of a plurality of communication paths by electrically branching a communication path; a plurality of receiving sections each of which is connected to the branching section for receiving the identical test packets and calculating delay times based on the sending time information; and a measurement value determining section for comparing a plurality of delay times calculated by each of the plurality of receiving sections for the identical test packets and determining the smallest delay time value as a measurement value.

Abstract: Packet transmission quality in a communication network is measured by transmitting a measurement packet from a packet transmission node to a packet reception node. The packet transmission node is provided with a transmission counter counting the number of packets transmitted from a packet transmission node to a packet reception node, and a measurement packet counter counting the number of measurement packets transmitted from the packet transmission node to the packet reception mode. The packet reception node is provided with a reception counter counting the number of packets received from the packet transmission node. The packet transmission node transmits a measurement packet including a transmission counter value and a measurement packet counter value, to the packet reception node which calculates the number of lost packets or a loss rate of packets on the basis of the transmission counter value, the measurement packet counter value, and a reception counter value.

Abstract: A path analyzer to obtain an address of a relay node on a path between a first terminal device and a second terminal device includes: a first address obtaining unit to issue a command requiring a response from the first terminal device to the second terminal device and to obtain as a first address an address of a first terminal device side in the relay node on the path; a broadcast processing unit to search a candidate address for a broadcast address from the relay node according to the first address obtained and to issue a command requiring a response from the first terminal device to the candidate address; and a second address obtaining unit to obtain as a second address an address of a second terminal device side in the relay node on the path according to a response to the command issued by the broadcast processing unit.

Abstract: A determination apparatus includes a processor and a storage unit. The processor acquires through a communication network a request packet transmitted from a client device to a server device group or a reply packet transmitted from the server device group to the client device. The server device group includes a first server device and one or more second server devices. The first server device is connected to the client device through the communication network. The storage unit stores configuration information for determining a source of the acquired reply packet. The processor determines whether the source of the acquired reply packet is the first server device or one of the second server devices on the basis of the configuration information stored in the storage unit.

Abstract: An apparatus to collect information about network failure includes: a normal mode packet assembly unit to assemble a transmission packet from transmission data output from an application in a normal mode being a procedure used when a transmission process is performed by specified communication protocol; a special mode packet assembly unit to assemble the transmission packet from the transmission data in a special mode being a procedure in which a procedure for collecting failure information is embedded into the procedure used when a transmission process is performed by the specified communication protocol; a switching control unit to activate the normal mode packet assembly unit or the special mode packet assembly unit selectively; and a response analysis unit to collect failure information according to a behavior of the response to the transmission packet transmitted from the special mode packet assembly unit.

Abstract: Measuring devices are connected to the same network. A sharing control processing unit controls sharing of capture of packets among the measuring devices. An aggregating unit collects the captured packets. Each measuring device notifies the sharing control processing unit of a state about its capture. The sharing control processing unit determines which measuring device is to start/stop the capture, according to a predetermined rule and the notified state. When determining that the capture is to be switched from a first measuring device to a second measuring device, the sharing control processing unit instructs the second measuring device to start the capture. After receiving a notification that the second measuring device has actually captured a packet(s), the sharing control processing unit instructs the first measuring device to stop the capture. The aggregating unit identifies a duplicate packet(s) double captured by the first and second measuring devices, and reconstructs the packets.

Abstract: An information processing apparatus can be installed in a DMZ and is connectable to an intranet and to an external network. The apparatus includes first means for transmitting or receiving a signal over the intranet, and transmitting or receiving a signal over the external network, to cause a call to be established over both of the intranet and the external network; and second means for transmitting and receiving data over the established call.

Abstract: A server apparatus having a plurality of interfaces to each of which a network is connected, the server apparatus includes an application identification device for identifying an application program which is a source of a packet, on the basis of information in the packet, when the packet is sent to a network connected to any one of the plurality of interfaces, an interface designation device for designating one interface which is previously caused to correspond to an identified application program, among the plurality of interfaces, as a sending interface which is used in routing of the packet, and an routing device for sending the packet to a network connected to a designated interface.

Abstract: Only when a request formed of a plurality of request packets obtained by dividing the request is reconstructed, the request is transmitted to a survey target node that returns a response formed of a plurality of response packets obtained by dividing the response. When no response packet has been received at all from the survey target node, it is determined that any of the request packets has been discarded on a first route from a surveying node as a transmission source of the request to the survey target node. When one or more response packets have been received from the survey target node but the response cannot be reconstructed, it is determined that any of the response packets transmitted from the survey target node has been discarded on a second route from the survey target node to the surveying node as the transmission source of the request packets.

Abstract: When simulating communication using a communication network such as a VoIP network, an actual communication state is accurately simulated, and communication is simulated. The distribution of delay times of packets is transformed by a predetermined transformation method, packet transmission timings to which delay times are added, are calculated based on the transformed distribution of delay times and predetermined transmission timings, a determination is made as to whether or not the packet transmission order is changed by the calculated transmission timings to which delay times are added, and, when a determination is made that the packet transmission order is changed, packet transmission timings adjusted so as not to cause a change in the transmission order are derived.

Abstract: The present invention enables accurate simulation of the state of communication over a communication network in which a communication channel of different communication characteristic is set for each protocol and session, such as a VoIP network built in a multi-vendor environment, and evaluation of communication quality of communications between IP phones, etc. over a supposed communication network. A relay device for relaying packet communications between a plurality of communication devices is used, and the relay device sets a virtual processing unit as an initial process so that it corresponds to the packet transmission direction and/or attribute, based on the contents of a received packet specified by a control protocol, and relays communications of packets after the initial process, based on the packet loss rate and delay time distribution indicated by communication state information associated with the processing unit.

Abstract: The present invention enables accurate simulation of the state of communication over a communication network in which a communication channel of different communication characteristic is set for each protocol and session, such as a VoIP network built in a multi-vendor environment, and evaluation of communication quality of communications between IP phones, etc. over a supposed communication network. A relay device for relaying packet communications between a plurality of communication devices is used, and the relay device sets a virtual processing unit as an initial process so that it corresponds to the packet transmission direction and/or attribute, based on the contents of a received packet specified by a control protocol, and relays communications of packets after the initial process, based on the packet loss rate and delay time distribution indicated by communication state information associated with the processing unit.

Abstract: A network management apparatus includes: a receiving unit for receiving from a first network apparatus a notification of a communication method setting incompatibility with a second network apparatus connected to a first port of the first network apparatus; and a setting unit for setting on the second network apparatus a communication method of the second port of the second network apparatus connected to the first network apparatus such that the communication method of the second port matches a communication method of the first port of the first network apparatus.

Abstract: The traffic load density measuring system includes a transmitter connected to a communication network for transmitting a packet, and a receiver for receiving the packet, in which a packet for load density detection is transmitted and received to measure a traffic load density within a predetermined transmission interval. The transmitter changes a transmission interval of the packet for load density detection, and adds transmission information capable of specifying a transmission time, a transmission interval, and a transmission number of the packet for load density detection to the packet for load density detection to transmit said packet. The receiver receives the packet for load density detection, extracts the transmission information from the packet for load density detection being received, and measures the load density within the predetermined transmission interval based on the extracted transmission information, and a delay or a lost status of the packet for load density detection.

Abstract: A method executed by a packet analysis apparatus for analyzing packets including voice packets and non-voice packets includes: capturing packets in a specific session; storing the captured packets in a storage; screening the stored packets to count up a receipt count of voice packets; determining whether packet loss has occurred in the specific session; and determining whether loss packets are voice packets in accordance with received packets adjacent to the loss packets to count up a loss count of voice packets when the packet loss has occurred.

Abstract: Communication quality values such as delay times of packets transmitted and received within a packet network are measured, and a threshold value is calculated based on the measured communication quality values. Further, a management reference value is calculated based on the communication quality values of packets whose measured communication quality values are within a range based on the threshold value. A communication state is detected by comparing the measured communication quality values with the management reference value.

Abstract: A relay device which forwards a packet received from a first device to a second device, the relay device includes a detection unit that detects that the relay device has been in a specified state, a generation unit that generates a packet that contains information for identifying the relay device and information indicating that the relay device is in the specified state when the detection unit detects that the relay device has been in the specified state, and a transmission unit that transmits the generated packet to a specific transmission destination.

Abstract: A system includes a unit transmitting test packets to a to-be-measured communication link at a first time interval, a unit transmitting burst loads each including a series of load packets to the communication link at a second time interval, a unit performing measurement of delay time periods in a manner that a plurality of test packets transmitted by varying elapsed time periods each from an instance of transmission of the burst load to an instance of transmission of the test packet are received from the communication link in a fluctuating time interval, a unit generating delay distributions indicative of packet occurrence frequencies in relation to a delay time period of the communication link in accordance with the measured delay time periods, and a unit calculating a network load in accordance with occurrence frequencies in a specific section of the generated delay distributions.

Abstract: The present invention includes a designating packet transferring step, a measurement packet transmitting step and a measurement packet collecting step. The designating packet transferring step is a step of transferring a designating packet in a target section for a communication performance measurement in the communication network, the designating packet designating a relaying apparatus which adds information to the measurement packet from among plural relaying apparatuses. The measurement packet transmitting step is a step of transmitting a measurement packet from one end of the target section. The measurement packet collecting step is a step of collecting the measurement packet transferred in the target section from among measurement packets which are transmitted in the measurement packet transmitting step.