Abstract: A throughput measuring method includes: acquiring a plurality of data packets at an observation point on a network, the plurality of data packets being transmitted from a transmission source apparatus and received by a transmission destination apparatus; calculating a plurality of round trip times, for each of the data packets, from a time point of acquisition of each of the data packets transmitted from the transmission source apparatus to a time point of acquisition of response packet corresponding to each of the data packets; identifying a measurement time section including the plurality of calculated round trip times increasing in ascending order of identification numbers of the response packets; and calculating a throughput of the identified measurement time section based on data quantities of the plurality of data packets transmitted from the transmission source apparatus during the identified measurement time section.

Abstract: An operation unit detects that a received first ACK packet is an ACK packet transmitted in response to a single data packet. The operation unit determines whether to calculate a round trip time by using reception time of the first ACK packet on the basis of a window size included in the first ACK packet and a window size included in a second ACK packet acquired immediately before the first ACK packet. If the operation unit determines to calculate the round trip time, the operation unit outputs the round trip time calculated by using the reception time of the first ACK packet.

Abstract: An analyzing device includes a memory and a processor coupled to the memory. The processor is configured to receive an acknowledgement from a wireless communication device for each of a plurality of data which is transmitted through a wired network and transmitted to the wireless communication device by a wireless communication which is capable of retransmitting data, from the wired network, calculate a reception interval of the plurality of acknowledgements, and analyze a retransmission cycle in the wireless communication based on a difference of the calculated reception interval of the plurality of acknowledgements.

Abstract: A network analysis method performed by a computer, the network analysis method includes receiving packets from a wired network, extracting a plurality of continuous packets transmitted by a communication device, and a plurality of acknowledgement packets transmitted by a wireless communication device in response to the plurality of continuous packets, and determining whether a delay is due to a wireless communication between the wireless communication device and an access point, based on a time interval of the plurality of continuous packets, and a time interval of the plurality of acknowledgment packets.

Abstract: A network analysis method using an information processing device includes receiving packets from a wired network; extracting, from a set of the received packets, a delay packet that was received after at least a predetermined period of time had elapsed since an immediately preceding packet was received; and determining that a packet delay because of a control signal wirelessly sent from an access point coupled to the wired network has occurred, based on periodicity of a timing at which the delay packet was received.

Abstract: A storage unit stores a plurality of packets collected in a wired section. An operation unit classifies the plurality of packets stored in the storage unit for each connection. The operation unit determines packets corresponding to a connection having a period in which a total data amount of packets for each of which a confirmation response packet has not arrived from a destination apparatus among packets transmitted by an information processing apparatus connected to the wired section increases when the connection is started, a round-trip time of each of the packets transmitted by the information processing apparatus not increasing monotonically in the period, to be packets of communication including the wireless section.

Abstract: In an analysis apparatus, when detecting each packet communicated via a network, an update unit updates statistical information that is stored in a continuous storage area of a storage unit and that indicates the communication state of the network for a first cycle. Then, a first processing unit reads the statistical information from the storage unit at every first cycle, and processes the statistical information and initializes the statistical information in the storage unit. A second processing unit reads partial statistical information that is part of the statistical information from the storage unit at every second cycle shorter than the first cycle, and processes the partial statistical information and initializes the partial statistical information in the storage unit.

Abstract: A monitoring apparatus includes a processor to execute a process that includes calculating the delay of each of the data among acquired series of data transmitted from a communication apparatus that performs transmission processing with regularity; extracting from the series of data, a set of data whose calculated delays are greater than or equal to a threshold; and identifying, from among the extracted set of data, a pattern of data appearing successively for a given number of times or more, at equivalent intervals; and an output device that outputs information indicating the data related to the identified pattern.

Abstract: A monitoring apparatus may receive data transmitted from a transmitting source apparatus at predetermined time intervals, via relay apparatuses configured to make a retransmission request depending on a reception error, and measure a reception time interval between consecutively received data. The monitoring apparatus may judge which one of the relay apparatuses is making the retransmission request, based on the measured reception time interval.

Abstract: A packet analysis method includes acquiring a first acknowledge packet and a second acknowledge packet transmitted from the first device; acquiring a plurality of packets transmitted from the second device during a period from reception of the first acknowledge packet to reception of the second acknowledge packet; identifying a number of packets corresponds to data transmitted from the second device, by calculating a difference between a first identification number corresponding to the first acknowledge packet and a second identification number corresponding to the second acknowledge packet; calculating a plurality of bandwidth values, a number of the plurality of bandwidth values is identical to the number of packets, based on acquisition timings of the plurality of packets and an interval between the acquisition timings of two adjacent packets; and determining a bandwidth value that is to be removed from the plurality of bandwidth values by comparing the plurality of bandwidth values.

Abstract: A packet analysis device includes a processor that executes a process including receiving a packet to be transmitted to a terminal device through a relay device, calculating a delay time indicating time taken by the relay device from start to completion of the transmission of the packet according to the received packet, and analyzing communication quality between the relay device and the terminal device when a reception interval of the packet is longer than the delay time.

Abstract: An analyzing device includes a memory and a processor coupled to the memory. The processor is configured to receive an acknowledgement from a wireless communication device for each of a plurality of data which is transmitted through a wired network and transmitted to the wireless communication device by a wireless communication which is capable of retransmitting data, from the wired network, calculate a reception interval of the plurality of acknowledgements, and analyze a retransmission cycle in the wireless communication based on a difference of the calculated reception interval of the plurality of acknowledgements.

Abstract: A method for judging delivery status of a push signal includes: receiving packets flowing in a specific session between a transmission source and transmission destination at an arbitrary point on a route of the specific session, and storing the received packets into a storage device, wherein the packets include voice packets and non-voice packets representing the push signal; judging based on sequence numbers included in the received packets stored in the storage device, whether or not packet loss has occurred in the specific session; and upon detecting that the packet loss has occurred, judging, according to status of the packet loss and predetermined characteristic of the non-voice packets, whether or not loss of the push signal has occurred.

Abstract: A network analysis method performed by a computer, the network analysis method includes receiving packets from a wired network, extracting a plurality of continuous packets transmitted by a communication device, and a plurality of acknowledgement packets transmitted by a wireless communication device in response to the plurality of continuous packets, and determining whether a delay is due to a wireless communication between the wireless communication device and an access point, based on a time interval of the plurality of continuous packets, and a time interval of the plurality of acknowledgment packets.

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: A loss determining unit of a monitoring device calculates a receiving-time interval between a receiving time of data and the receiving time of immediately previous data. If the interval is a predetermined threshold or higher, the loss determining unit determines that “a loss is detected” and calculates the number of losses. If the number of losses is lower than the threshold, the loss determining unit determines that “no loss is detected”. A failure-section determining unit calculates the number of losses occurring in a first section. The failure-section determining unit calculates the number of losses occurring in a second section. If the loss is detected in the first section, the failure-section determining unit determines that a failure occurs in the first section. If the loss is detected in the second section, the failure-section determining unit determines that a failure occurs in the second section.

Abstract: A network analysis method using an information processing device includes receiving packets from a wired network; extracting, from a set of the received packets, a delay packet that was received after at least a predetermined period of time had elapsed since an immediately preceding packet was received; and determining that a packet delay because of a control signal wirelessly sent from an access point coupled to the wired network has occurred, based on periodicity of a timing at which the delay packet was received.

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: A sharing control processing unit controls sharing of capture of packets among measuring devices connected to the same network. 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.

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.