JP2011142622A - System and method for measurement of network band, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a system and method for measurement of a network band, along with a program, capable of measuring an available band or achievable UDP throughput in a short time. <P>SOLUTION: A plurality of measuring packets of packet sizes to be increased or decreased sequentially are transmitted from a transmitting side at a predetermined transmission interval (step S1). At a receiving side, the measuring packets transmitted are received and a reception interval of the measuring packets is measured (step S2). The transmission interval in transmitting the measuring packets is compared with the reception interval upon receiving the measuring packets and a measuring packet having the maximum packet size in the measuring packets, of which the reception interval and the transmission interval are equal, is used to calculate an available band (step S3). <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a network bandwidth measurement system, method, and program, and more specifically, a network bandwidth measurement that simultaneously measures a bandwidth that can be used for communication on a communication path between terminals in a short time and a throughput that can be achieved by UDP communication. The present invention relates to a system, a method, and a program.

  The network bandwidth measurement system uses a bandwidth that can be used in an IP (Internet Protocol) network (hereinafter referred to as an available bandwidth) and / or a throughput that can be achieved through UDP (User Datagram Protocol) communication (hereinafter referred to as an achievable UDP throughput). ). The available bandwidth is a free bandwidth obtained by subtracting other traffic (hereinafter referred to as cross traffic) flowing in the IP network from the physical bandwidth of the IP network. For example, if the physical bandwidth is 100 Mbps and the cross traffic is 30 Mbps, the available bandwidth is 100 Mbps-30 Mbps = 70 Mbps.

  Also, the achievable UDP throughput is the maximum transmission rate that can push away the cross traffic when a UDP packet flows in the IP network. UDP communication does not have a congestion control function for detecting congestion of an IP network by detecting packet loss as in TCP (Transmission Control Protocol) communication and reducing the transmission rate by itself. Therefore, if UDP communication is injected into the IP network while TCP traffic or UDP communication cross traffic is flowing, packet loss will occur in the cross traffic TCP communication, and the transmission rate will be lowered by congestion control. The phenomenon of pushing down the throughput in competition with the UDP communication occurs.

  Therefore, due to the interaction between the above-described UDP communication and cross traffic, even if a large amount of cross traffic flows and the usable bandwidth is 0 Mbps, if UDP communication is newly injected, the throughput of the UDP communication is not necessarily 0 Mbps. In some cases, a positive throughput such as 5 Mbps may be obtained. Since the cross traffic and the newly injected UDP communication are mixed, there is an upper limit to the throughput that can be acquired by the newly injected UDP communication, and this upper limit becomes the achievable UDP throughput. In other words, it should be noted that the available bandwidth value does not necessarily match the achievable UDP throughput value. In addition, the achievable UDP throughput changes depending on the size of the physical bandwidth, the ratio and number of TCP and UDP communications included in the cross traffic, and can be achieved even if the values of the physical bandwidth and available bandwidth are known. The value of the UDP throughput cannot be known.

  In summary, the available bandwidth is a bandwidth that can be used in a range where packet loss does not occur, and the achievable UDP throughput is a transmission rate that can be acquired by one newly injected UDP communication, although packet loss occurs to some extent. It is the maximum value.

  Understanding the available bandwidth is important when sharing photos or materials between terminals in real time without causing packet loss, or when making a voice call between terminals. For example, consider a case where photos are shared in real time between terminals, and a plurality of sizes such as large, medium, and small are prepared for each photo in advance. In this case, when the available bandwidth is known when sharing a photo, it is possible to calculate in advance how many seconds it is possible to send a photo to be sent to the partner terminal for each size. Compare the time required for transmission for each size and the allowable value for the time required for transmission. For example, if the medium size and the small size can be sent to the other party within the allowable value, the transmission is performed. The size of the photo is medium. By doing in this way, the highest definition photograph can be sent to the other party within an allowable time.

  Further, consider a case where a multi-party audio conference is performed by connecting a plurality of terminals with a full mesh without causing packet loss. It is assumed that the bandwidth consumed by one voice in a multiparty audio conference is a known fixed value. In this case, it is possible to calculate in advance how many terminals can participate in the multiparty audio conference if the available bandwidth is known at the start of the multiparty conference.

  Non-Patent Document 1 is a document in which measurement of an available bandwidth is described. In Non-Patent Document 1, a plurality of measurement packet sequences having a fixed size are transmitted from the transmission side terminal to the reception side terminal as one set. In Non-Patent Document 1, the available bandwidth is measured by detecting a change in the reception interval of each measurement packet at the receiving terminal. In Non-Patent Document 1, when a measurement packet sequence is transmitted from a transmission side terminal, the transmission interval of each measurement packet is exponentially decreased. By reducing the transmission interval exponentially, the transmission rate of measurement packets increases exponentially within the measurement packet sequence.

  If a cross-traffic packet is sandwiched between measurement packets when the measurement packet passes through the network, the transmission rate of the measurement packet may exceed the available network bandwidth. When the transmission rate of the measurement packet exceeds the usable bandwidth, the reception interval of the measurement packet at the reception side terminal increases with respect to the transmission interval at the transmission side terminal. In Non-Patent Document 1, by utilizing this property, the reception side terminal detects a part where the reception interval of the measurement packet starts to increase as compared with the transmission interval at the transmission side terminal, and the packet size of the measurement packet is set to The available bandwidth is calculated by dividing by the transmission interval at each location.

  Patent Document 1 is a document in which a method for searching for an available bandwidth is described. In Patent Literature 1, an operation of transmitting a measurement packet sequence having a fixed size and an equal time interval from a transmission side terminal to a reception side terminal is repeatedly executed a plurality of times. When it is determined that the reception interval tends to increase in the reception side terminal, the transmission side terminal transmits a measurement packet sequence in which the transmission interval is decreased exponentially to the reception side terminal. Conversely, when it is determined that the reception interval is decreasing in the reception side terminal, the transmission side terminal transmits a measurement packet sequence in which the transmission interval is exponentially increased to the reception side terminal. In Patent Document 1, such an operation is repeatedly performed to search for an available band by performing a binary search.

  In Non-Patent Document 1, the transmission interval between measurement packets in a packet train changes, whereas in Patent Document 1, the transmission interval of measurement packets in a single packet train is always constant, and for each packet train, The transmission interval between measurement packets changes.

  Understanding the achievable UDP throughput is important when making video and voice calls using UDP communication between terminals, assuming that the available bandwidth is narrow and packet loss will occur to some extent. is there. For example, by applying redundancy to video packets using FEC (forward error correction) and performing a video call at a transmission rate that does not exceed the achievable UDP throughput, even if packet loss occurs to some extent, the effect In addition, the video call can be performed at a transmission rate within a range that can be transmitted.

  Here, the method of determining the video transmission rate based on the achievable UDP throughput is more effective when the available bandwidth is narrower than the method of determining the video transmission rate based only on the available bandwidth. It should be noted that there is an advantage that the transmission rate can be increased.

  Patent Document 3 describes a method of calculating the throughput of the MAC layer in the wireless LAN, not the achievable UDP throughput itself. If the achievable throughput of the MAC layer in the wireless LAN can be estimated, it is considered that the achievable UDP throughput on the wireless LAN can be approximated using the estimated value. In Patent Literature 3, a MAC frame of a fixed size is continuously transmitted from a measurement terminal to a wireless LAN access point (AP) at a specified transmission rate, so that the number of MAC frames transmitted from the measurement terminal and the AP of the wireless LAN are determined. The achievable throughput of the MAC layer in the wireless LAN is calculated using the three parameters of the frame error rate calculated from the number of ACKs returned from the MAC layer, the size of the MAC frame, and the designated transmission rate.

  Patent Document 2 describes a technique for determining an optimum packet size of data to be transmitted to a target network address. In Patent Document 2, test data with a changed packet size is repeatedly transmitted from one terminal to another terminal, and the transmitting terminal checks whether there is a response from the receiving terminal. Is described. This test data transmission is performed for the purpose of examining to what packet size the network devices constituting the data communication path are compatible. In Patent Document 2, for this purpose, the packet size of the test data includes a packet size that exceeds the upper limit of the packet size that can be handled by the network device that configures the communication path.

Japanese Patent No. 4153510 JP 2007-281801 A JP 2007-116329 A

Vinay J. Ribeiro, Rudolf H. Riedi, Richard G. Baraniuk, Jiri Navratil and Les Cottrell, "pathChirp: Efficient Available Bandwidth Estimation for Network Paths," in Proc of Passive and Active Measurement Workshop 2003.

  In Non-Patent Document 1, it is necessary to increase the transmission interval between the first measurement packet and the second measurement packet in order to measure the available bandwidth even when the available bandwidth is small. For this reason, in Non-Patent Document 1, it is impossible to finish sending a packet train only in a time linearly proportional to the number of measurement packets constituting the packet train, and it is not possible to measure the available bandwidth in a short time.

  Here, in Non-Patent Document 1, when the transmission interval between the first measurement packet and the second measurement packet is reduced, the transmission rate of the measurement packet sequence is increased from the beginning. In addition, the transmission rate of subsequent measurement packets increases exponentially, and only a very large usable bandwidth can be detected. For this reason, in order to detect a small usable bandwidth, the transmission interval between the first measurement packet and the second measurement packet must be increased.

  In Patent Document 1, the available bandwidth cannot be calculated simply by transmitting a single packet train, and it is necessary to repeatedly transmit the packet train many times in order to perform a binary search. For this reason, even with the technique described in Patent Document 1, the available bandwidth cannot be measured in a short time. Patent Document 2 aims to determine an optimum packet size used for communication, and does not measure the available bandwidth.

  In Patent Document 3, it is necessary to wait for a retransmission timeout of the MAC frame when there is no ACK reply, so it takes time for one measurement. Furthermore, since the throughput that actually flows with respect to the designated transmission rate is measured, the achievable throughput that is the maximum throughput is not always known by one measurement. For example, the achievable throughput cannot be measured unless measurements are performed many times while gradually increasing the designated transmission rate. Therefore, the achievable throughput cannot be measured in a short time.

  Non-Patent Document 1, Patent Document 1, and Patent Document 2 cannot measure the achievable UDP throughput, and Patent Document 3 cannot measure the available bandwidth. Therefore, when measuring both the available bandwidth and the achievable UDP throughput, the measurement packet must be transmitted individually.

  An object of the present invention is to provide a network bandwidth measurement system, method, and program capable of solving the above-described problems and measuring available bandwidth or achievable UDP throughput in a short time.

In order to achieve the above object, a network bandwidth measurement method according to the first aspect of the present invention includes a step of transmitting a plurality of measurement packets whose packet sizes sequentially increase or decrease at a predetermined transmission interval;
Receiving the transmitted measurement packet and measuring a reception interval of the measurement packet;
Comparing the transmission interval with the measured reception interval, calculating an available bandwidth using a measurement packet having a maximum packet size among measurement packets having the same reception interval and the transmission interval;
It is characterized by providing.

The network bandwidth measurement system according to the second aspect of the present invention is:
Measurement packet generation means for generating a plurality of measurement packets in which the packet size is sequentially increased or decreased;
Measurement packet transmission means for transmitting a plurality of measurement packets generated by the measurement packet generation means at a predetermined transmission interval;
A reception interval measuring means for receiving the transmitted measurement packet and measuring a reception interval of the measurement packet;
Available bandwidth calculation means for comparing the transmission interval with the measured reception interval and calculating an available bandwidth using a measurement packet having the largest packet size among the measurement packets having the same reception interval and the transmission interval. When,
It is characterized by providing.

A transmission side apparatus according to a third aspect of the present invention is:
Measurement packet generation means for generating a plurality of measurement packets in which the packet size is sequentially increased or decreased;
Measurement packet transmission means for transmitting a plurality of measurement packets generated by the measurement packet generation means at a predetermined transmission interval;
It is characterized by providing.

The receiving-side apparatus according to the fourth aspect of the present invention is:
A reception interval measuring means for receiving a plurality of measurement packets that are sequentially increased or decreased in packet size, transmitted at a predetermined transmission interval, and measuring a reception interval of the measurement packets;
The measurement packet transmission interval is compared with the measured reception interval, and the available bandwidth is calculated using the measurement packet having the largest packet size among the measurement packets having the same reception interval and the transmission interval. Bandwidth calculation means;
It is characterized by providing.

A program according to a fifth aspect of the present invention is stored in a computer.
Processing to generate multiple measurement packets with increasing or decreasing packet size sequentially,
A process of transmitting the plurality of measurement packets at a predetermined transmission interval;
Is executed.

A program according to a sixth aspect of the present invention is stored in a computer.
A process in which the packet size sequentially increases or decreases, receives a plurality of measurement packets transmitted at a predetermined transmission interval, and measures the reception interval of the measurement packets;
A process of comparing the transmission interval of the measurement packet with the measured reception interval, and calculating an available bandwidth using a measurement packet having a maximum packet size among measurement packets having the same reception interval and the transmission interval; ,
Is executed.

A network bandwidth measuring method according to a seventh aspect of the present invention is:
Transmitting a plurality of measurement packets whose packet sizes sequentially increase or decrease at predetermined transmission intervals;
Receiving the transmitted measurement packet and measuring a reception interval of the measurement packet;
Calculating the reception rate of each measurement packet by dividing the packet size of each measurement packet by the reception interval of each measurement packet measured by the reception interval measurement means;
Judging whether the reception rate is saturated by looking at the reception rate in order from the smallest packet size of the measurement packet;
Calculating the achievable UDP throughput using the reception rate of the measurement packet when it is determined that the reception rate is saturated, in order from the smallest packet size of the measurement packet;
It is characterized by providing.

  The network bandwidth measurement system, method, and program of the present invention can measure available bandwidth or achievable UDP throughput in a short time.

It is a flowchart which shows the general | schematic procedure of the available zone | band measuring method of this invention. It is a block diagram which shows schematic structure of the transmission side apparatus of this invention. It is a block diagram which shows schematic structure of the receiving side apparatus of this invention. It is a block diagram which shows the network band measurement system which concerns on Embodiment 1 of this invention. It is a block diagram which shows the structure of a transmission side apparatus and a receiving side apparatus. It is a figure which shows a packet train at the time of transmission. It is a figure which shows a packet train at the time of reception. It is a figure which shows an example of the measurement data of a measurement packet. 4 is a flowchart showing an example of an operation of available bandwidth measurement according to the first embodiment. It is a block diagram which shows the structure of the network band measurement system which concerns on Embodiment 3 of this invention. It is a figure which shows the data structure of the measurement data which concerns on Embodiment 3. FIG. It is a figure which shows typically the mechanism of calculation of achievable UDP throughput. 12 is a flowchart illustrating an example of an operation of achievable UDP throughput measurement according to the third embodiment. It is a block diagram which shows the physical structural example of the transmission side apparatus or receiving side apparatus which concerns on embodiment of this invention.

  Prior to the description of the embodiments of the present invention, an outline of the present invention will be described. FIG. 1 is a flowchart showing a schematic procedure of an available bandwidth measuring method of the present invention. First, a plurality of measurement packets whose packet sizes are sequentially increased or decreased are transmitted from the transmission side at a constant transmission interval (step S1). Next, the measurement packet transmitted from the transmission side is received on the reception side, and the reception interval of the measurement packets continuously received is measured (step S2). After that, compare the transmission interval at the time of transmission of the measurement packet with the reception interval at the time of reception of the measurement packet, and use the measurement packet with the largest packet size among the measurement packets with the same reception interval and transmission interval The bandwidth is calculated (step S3).

  FIG. 2 is a block diagram showing a schematic configuration of the transmission side apparatus of the present invention. The transmission side device 10 includes a measurement packet generation unit 11 and a measurement packet transmission unit 12. The measurement packet generation unit 11 generates a plurality of measurement packets in which the packet size is sequentially increased or decreased. The measurement packet transmission unit 12 transmits the plurality of measurement packets generated by the measurement packet generation unit 11 to the receiving device at a predetermined transmission interval.

  FIG. 3 is a block diagram showing a schematic configuration of the receiving side apparatus of the present invention. The reception-side device 20 includes a reception interval measurement unit 21 and an available bandwidth calculation unit 22. The reception interval measuring means 21 receives a plurality of measurement packets transmitted at a predetermined transmission interval from the transmission side device, and the packet size increases or decreases sequentially, and measures the reception interval of the measurement packets. The available bandwidth calculation means 22 compares the transmission interval at the time of transmission of the measurement packet with the reception interval at the time of reception of the measurement packet. The available bandwidth calculating means 22 calculates the available bandwidth using the measurement packet having the largest packet size among the measurement packets having the same reception interval and transmission interval.

  In the present invention, measurement packets whose packet size sequentially increases or decreases are transmitted from the transmission side at a predetermined transmission interval. On the reception side, the reception interval of the measurement packet transmitted from the transmission side is measured, and the available bandwidth is calculated using the measurement packet having the maximum packet size among the measurement packets whose reception interval is equal to the transmission interval. In the present invention, it is not necessary to repeat the transmission of the measurement packet train, and the available bandwidth of the communication path from the transmission side to the reception side can be measured by transmitting a single measurement packet train. Moreover, since the transmission intervals of the measurement packets are equal, transmission of the measurement packet train can be completed in a time linearly proportional to the number of measurement packets. Therefore, in the present invention, the available bandwidth can be measured in a short time.

(Embodiment 1)
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 4 shows a network configuration of the network bandwidth measurement system according to Embodiment 1 of the present invention. The network bandwidth measurement system includes a transmission side device 101 and a reception side device 102. The transmission side apparatus 101 and the reception side apparatus 102 are connected via a network 103. Devices not shown other than the transmitting device 101 and the receiving device 102 may be connected to the network 103, and cross traffic may flow between these devices (not shown).

  The transmission side device 101 and the reception side device 102 are a personal computer (PC), a portable computer (PDA), a mobile phone, a smartphone, a landline phone, a street multimedia terminal, an in-vehicle terminal, a TV with a network connection function, and a network connection function. It can be composed of devices such as a set-top box, a game machine, a printer with a network connection function, and a scanner with a network connection function. The transmission side device 101 and the reception side device 102 are not limited to these, and may be other similar devices having a function of exchanging information with the outside.

  FIG. 5 is a block diagram illustrating the configuration of the transmission side device and the reception side device. The transmission-side apparatus 101 includes a measurement packet generation unit 110, a measurement packet transmission unit 111, a transmission / reception unit 112, and a parameter storage unit 113. The reception side device 102 includes a transmission / reception unit 120, a reception interval measurement unit 121, an available bandwidth calculation unit 122, and a measurement data storage unit 123. The functions of each means in the transmission side apparatus 101 and the reception side apparatus 102 can be realized by the computer operating according to a predetermined program.

  The measurement packet generation unit 110 of the transmission side apparatus 101 generates a plurality of measurement packets to be transmitted to the reception side apparatus 102. The measurement packet generated by the measurement packet generation unit 110 is transmitted to the reception side apparatus 102 as a packet train. The measurement packet generation unit 110 generates a measurement packet whose packet size gradually increases from the first packet to the last packet in the packet train. The transmission / reception means 112 performs data transmission to the network 103 and data reception from the network 103. The measurement packet transmission unit 111 transmits measurement packets at a predetermined transmission interval via the transmission / reception unit 112.

  The parameter storage unit 113 stores a minimum packet size, a packet increase size, and a measurement packet transmission interval. The measurement packet generation unit 110 refers to the parameter storage unit 113, and generates a measurement packet that is increased from the minimum packet size by the packet increase size. The measurement packet transmission unit 111 transmits the measurement packet at the transmission interval stored in the parameter storage unit 113.

  Here, the minimum packet size, the packet increase size, and the number of measurement packets constituting the packet train are set so that the packet size of the measurement packet constituting the final packet is within the range of packet sizes that can pass through the network 103. Is set. That is, the packet size of each measurement packet constituting the packet train is all set to a packet size that can reach the receiving apparatus 102 through the network 103.

  The transmission / reception means 120 of the receiving apparatus 102 receives the measurement packet transmitted by the transmitting apparatus 101. The reception interval measurement unit 121 stores information (measurement data) regarding the received measurement packet in the measurement data storage unit 123. The measurement data includes a reception interval of measurement packets. The available bandwidth calculation unit 122 calculates the available bandwidth based on the measurement data of the measurement packet received by the transmission / reception unit 120. More specifically, the available bandwidth calculation unit 122 compares the reception interval when receiving the measurement packet with the transmission interval when transmitting the measurement packet. The available bandwidth calculating unit 122 calculates the available bandwidth using the measurement packet having the largest packet size among the measurement packets having the same reception interval and transmission interval.

  The available bandwidth calculation unit 122 stores the calculated available bandwidth in the measurement data storage unit 123. In addition, the available bandwidth calculation unit 122 transmits the calculated available bandwidth to the transmission side device 101 via the transmission / reception unit 120. The transmission / reception unit 112 of the transmission side apparatus 101 receives the measurement result of the usable bandwidth transmitted by the reception side apparatus 102.

  FIG. 6 is a diagram illustrating a packet train during transmission. The transmission packet train 150 is a measurement packet train transmitted by the transmission side device 101. Here, the number of measurement packets generated by the measurement packet generation unit 110 is N (N is an integer of 3 or more). The packet number is a number for identifying a measurement packet. The transmission packet train 150 is composed of measurement packets from packet numbers 1 to N arranged in time series. For each measurement packet, for example, an IP (Internet Protocol) packet, a UDP (User Datagram Protocol) packet, an RTP (Real-time Transport Protocol) packet, or the like can be used.

  In the transmission packet train 150, the transmission interval of each measurement packet is equal to the transmission interval stored in the parameter storage means 113. That is, the time interval between adjacent measurement packets is equal. The packet size of the measurement packet with the packet number 1 is equal to the minimum packet size stored in the parameter storage unit 113. The packet size of the measurement packet with the packet number 2 is larger than the size of the measurement packet with the packet number 1 by the increased packet size stored in the parameter storage unit 113. Thereafter, the packet size of the measurement packet increases by the packet increase size every time the packet number increases by one. The measurement packet generator 110 includes a packet number, a packet size, and a transmission interval in each measurement packet.

  FIG. 7 is a diagram illustrating a packet train during reception. The reception packet train 160 indicates a measurement packet train received by the reception-side apparatus 102. The transmission-time packet train 150 is transmitted through the network 103 and received by the reception-side apparatus 102 as a reception-time packet train 160. In the reception packet train 160, until a certain point in time, the reception interval of the measurement packet is equal to the transmission interval at the time of transmission of the measurement packet. However, as the packet size of the measurement packet increases, the reception interval of the measurement packet becomes larger than the transmission interval at the time of transmission at a certain time.

  When the reception interval of the measurement packet becomes larger than the transmission interval, the available bandwidth calculation unit 122 calculates the available bandwidth using the measurement packet transmitted immediately before the measurement packet. Since the packet size of the measurement packet increases, the measurement packet transmitted immediately before the measurement packet whose reception interval is larger than the transmission interval is a packet out of the measurement packets having the same reception interval and transmission interval. Corresponds to the largest measurement packet. The available bandwidth calculation unit 122 calculates the available bandwidth based on the packet size and the transmission interval of the measurement packet transmitted immediately before the measurement packet whose reception interval is larger than the transmission interval.

  FIG. 8 is a diagram illustrating an example of measurement data of a measurement packet. The measurement data storage unit 123 stores measurement data with a configuration as shown in FIG. 8, for example. The measurement data storage unit 123 stores the packet number, packet size, transmission interval, and reception interval of the measurement packet received by the transmission / reception unit. When the transmission / reception unit 120 receives the measurement packet, the reception interval measurement unit 121 displays the packet number, the packet size, and the transmission interval included in the received measurement packet as the packet number, the packet size, and the measurement data storage unit 123, respectively. Store in the transmission interval. The reception interval measuring unit 121 obtains a measurement packet reception interval from the difference between the previous measurement packet reception time and the current measurement packet reception time, and the obtained reception interval is set as the reception interval of the measurement data storage unit 123. Store.

FIG. 9 is a flowchart showing an example of the operation of available bandwidth measurement according to the first embodiment. The measurement packet generator 110 generates N measurement packets that constitute the packet train (step S11). The measurement packet generation unit 110 sets the packet size of the measurement packet with the packet number 1 that is the head of the packet train as the minimum packet size stored in the parameter storage unit 113. The measurement packet generation unit 110 increases the packet size of the measurement packet by the packet increase size stored in the parameter storage unit 113 every time the packet number increases by one. If generalized, the measurement packet generator 110 determines the packet size of the i-th (i = 1, 2, 3,..., N) measurement packet as
Packet size = minimum packet size size + (i−1) × packet increase size. The measurement packet generation unit 110 includes a packet number, a packet size, and a transmission interval stored in the parameter storage unit 113 in each measurement packet.

  The measurement packet transmission unit 111 sequentially transmits the measurement packets generated by the measurement packet generation unit 110 to the reception-side apparatus 102 one by one via the transmission / reception unit 112 (step S12). At that time, the measurement packet transmission unit 111 sequentially transmits each measurement packet so that the interval between successive measurement packets becomes the transmission interval stored in the parameter storage unit 113. The measurement packet transmission unit 111 transmits each measurement packet at equal intervals up to the measurement packet of the packet number N in the order of the packet number 1, the packet number 2,... According to the packet number. The measurement packet transmitted from the transmission side apparatus 101 is received by the reception side apparatus 102 through the network 103.

  The transmission / reception means 120 of the receiving side apparatus 102 receives the measurement packet. When the transmission / reception unit 120 receives the measurement packet, the reception interval measurement unit 121 stores the packet number, the packet size, and the transmission interval included in the received measurement packet in the measurement data storage unit 123 (FIG. 8). The reception interval measuring unit 121 obtains the difference between the reception time of the measurement packet and the reception time of the previous measurement packet as the reception interval for the second and subsequent measurement packets, and stores the difference in the measurement data storage unit 123. To do. The available bandwidth calculation unit 122 checks the magnitude relationship between the reception interval of the measurement packet and the transmission interval included in the measurement packet every time the transmission / reception unit 120 receives the measurement packet (step S13).

  In the transmission packet train 150 (FIG. 6), since the size of the measurement packet gradually increases, the amount of data per unit time of the packet transmitted from the transmission side device 101 to the reception side device 102 gradually increases. Go. When the amount of data per unit time increases and exceeds the bandwidth available on the communication path from the transmission side apparatus 101 to the reception side apparatus 102, the reception interval of measurement packets received by the reception side apparatus 102 becomes the measurement packet transmission. It becomes larger than the transmission interval of time. Therefore, when the available bandwidth calculation unit 122 determines in step S13 that the measurement packet reception interval is larger than the transmission interval, the available bandwidth calculation unit 122 calculates the available bandwidth based on the packet size of the measurement packet and the transmission interval (step S14). ).

More specifically, the available bandwidth calculating means 122 calculates the available bandwidth in the following procedure in step S14. The available bandwidth calculator 122 first checks the packet number of the measurement packet whose reception interval is larger than the transmission interval. Let j be the packet number when the reception interval is larger than the transmission interval. Next, the available bandwidth calculation unit 122 acquires the packet size and transmission interval of the measurement packet whose packet number is j−1 from the measurement data storage unit 123. Thereafter, the available bandwidth calculating means 122
Useable bandwidth = (packet size of the j−1th measurement packet) ÷ Available bandwidth is calculated using a formula of transmission interval. The available bandwidth calculation unit 122 transmits the calculated available bandwidth to the transmission side device 101 via the transmission / reception unit 120.

  When the reception interval of the measurement packet is equal to the transmission interval at the time of transmission, the available bandwidth calculation unit 122 determines whether the packet number of the measurement packet is N (step S15). If it is determined in step S15 that the measurement packet number is not N, the reception-side apparatus 102 returns to step S13 and receives the next measurement packet. When the measurement packet number is N, that is, when the received measurement packet is the last measurement packet in the packet train, the available bandwidth calculation unit 122 cannot calculate the available bandwidth via the transmission / reception unit 120. Is transmitted to the transmission-side apparatus 101 (step S6).

  In the present embodiment, the transmission side apparatus 101 transmits measurement packets whose packet size gradually increases toward the reception side apparatus 102 at equal intervals. The receiving-side apparatus 102 detects a time point when the reception interval of the measurement packet becomes larger than the transmission interval, and calculates the available bandwidth based on the packet size and the transmission interval of the measurement packet immediately before that. In this embodiment, the transmission intervals of measurement packets are equal, and the packet train can be sent in a time proportional to the number of packets (N). In this embodiment, the available bandwidth can be obtained by transmitting a single packet train. Therefore, the available bandwidth can be measured in a short time.

  In this embodiment, the available bandwidth can be measured in a short time. For example, when photos and materials are shared between terminals in real time, transmission can be performed within the allowable time required for transmission of photos and materials. A large amount of data can be calculated in advance with a short waiting time. In addition, when a multi-party audio conference or video conference is started by connecting a plurality of terminals with a full mesh, it is assumed that the bandwidth consumed by one voice or video is a known fixed value, and up to how many terminals It is possible to calculate whether or not can participate in a multi-party audio conference and video conference with a short waiting time.

  In the above-described Patent Document 2, the terminal on the test data transmission side determines for each test whether there is a response to the test data from the terminal on the reception side. If the round-trip delay time (RTT) between terminals is R seconds, in Patent Document 2, it is necessary to wait for R seconds until a response is returned in one test, and in N tests, it is also necessary to wait for N × R seconds. There is. If no response is returned in one test, it is necessary to wait until timeout, so if it takes T seconds to timeout, it is necessary to wait N × T seconds to test N times. Therefore, in Patent Document 2, the test cannot be completed in a short time.

  On the other hand, in the first embodiment, the available bandwidth can be obtained by transmitting a single packet train. If the number of packets in the packet train used in the measurement of the available bandwidth is N and the packet transmission interval is S seconds, the measurement of the available bandwidth can be completed in (N−1) × S + R seconds. The round trip delay time R between terminals is, for example, a delay time of the order of 10 milliseconds between terminals across prefectures. In ping or the like, it usually takes several seconds until timeout, so the time T until timeout is, for example, about 3000 milliseconds. If N = 100, in Patent Document 2, it takes N × R = 100 × 10 = 1000 milliseconds or N × T = 100 × 3000 = 300,000 milliseconds before the test is completed. On the other hand, in the present embodiment, if the packet transmission interval S = 1 msec in the packet train, the available bandwidth can be obtained in (N−1) × S + R = 99 × 1 + 10 = 109 msec. It can be seen that the measurement of the available bandwidth can be completed in a short time.

(Embodiment 2)
The second embodiment is a case where the packet size of the measurement packet decreases sequentially. The configurations of the transmission side device and the reception side device in the second embodiment are the same as the configurations of the transmission side device 101 and the reception side device 102 in the first embodiment shown in FIG. In the present embodiment, the operation of the measurement packet generator 110 is different. That is, in the first embodiment, the measurement packet generation unit 110 generates a measurement packet having a packet size that increases from the minimum packet size in increments of the packet increase size. In the second embodiment, the maximum packet size and the packet decrease size are stored in the parameter storage unit 113, and the measurement packet generation unit 110 measures the measurement packet having a packet size that decreases from the maximum packet size by the packet decrease size. Is generated. Other points are the same as in the first embodiment.

  The packet train used in the second embodiment is equivalent to the packet train in the transmission packet train 150 shown in FIG. That is, the packet size of the measurement packet with the packet number 1 is the largest, and every time the packet number increases by one, the size of the measurement packet decreases by the packet decrease size, and the packet of the measurement packet with the packet number N The size is the smallest. When such a packet train is used as a transmission packet train, in the reception packet train received by the receiving side apparatus 102, the reception interval of the measurement packet is longer than the transmission interval at the time of transmission of the measurement packet until a certain point in time. Largely, after a certain point in time, the reception interval becomes equal to the transmission interval.

  In Embodiment 2, when the measurement packet reception interval becomes equal to the transmission interval, the available bandwidth calculation unit 122 calculates the available bandwidth based on the packet size of the measurement packet and the transmission interval at that time. . That is, the available bandwidth calculating unit 122 calculates the available bandwidth based on the packet size and the transmission interval of the first measurement packet whose reception interval is equal to the transmission interval. In the packet train used also in the second embodiment, the packet size of the measurement packet gradually decreases, so the first measurement packet in which the reception interval and the transmission interval are equal is the measurement packet in which the reception interval and the transmission interval are equal. Among these, it corresponds to the measurement packet with the largest packet size. In the second embodiment, the same effect as in the first embodiment can be obtained.

  In the first embodiment, the transmission / reception unit 120 of the receiving-side apparatus 102 receives the measurement packet, the packet number, the packet size, the transmission interval, and the reception interval of the received measurement packet every time the measurement packet is received. However, the present invention is not limited to this. Since the available bandwidth calculation unit 122 calculates the available bandwidth using the measurement data of the measurement packet immediately before the measurement packet whose reception interval is larger than the transmission interval, the measurement data storage unit 123 stores N It is not necessary to store the measurement data for all of the measurement packets, and it is only necessary to store the measurement data of the measurement packet received immediately before.

  In Embodiment 1, since the transmission interval is constant, the transmission / reception unit 120 does not need to store the transmission intervals of all measurement packets in the measurement data storage unit 123. Furthermore, since two pieces of information necessary for calculating the available bandwidth are the packet size and the transmission interval, the transmission / reception unit 120 may store the information in the measurement data storage unit 123 at a minimum. In FIG. 9, the reception interval and the transmission interval are compared each time a measurement packet is received, but the present invention is not limited to this. For example, the available bandwidth calculation unit 122 refers to the measurement data storage unit 123 after receiving all N measurement packets constituting the packet train, and identifies a measurement packet whose reception interval is larger than the transmission interval. Then, the available bandwidth may be calculated.

  In the flowchart of FIG. 9, the measurement packet generation unit 110 generates a measurement packet every time the available bandwidth is measured, but is not limited thereto. For example, instead of the measurement packet generating unit 110 generating the measurement packet, a plurality of measurement packets whose packet sizes increase may be stored in advance in a storage device (not shown). In that case, the measurement packet transmission unit 111 may read the measurement packet from the storage device and transmit it to the reception-side device 102.

  In the first embodiment, the size of the measurement packet is linearly increased in increments of the packet increase size, but the present invention is not limited to this. For example, the measurement packet generator 110 may generate a measurement packet whose packet size increases exponentially every time the packet number increases by setting the packet size of the first measurement packet as the minimum packet size. . In the second embodiment, the size of the measurement packet is linearly decreased by the packet decrease size. However, the present invention is not limited to this. For example, the measurement packet generator 110 may generate a measurement packet whose packet size decreases exponentially every time the packet number increases by setting the packet size of the first measurement packet as the maximum packet size.

(Embodiment 3)
In the network bandwidth measurement system according to the third embodiment, the achievable UDP throughput is measured. FIG. 10 is a block diagram showing the configuration of the network bandwidth measurement system according to Embodiment 3 of the present invention. The configuration of transmission side apparatus 104 in the third embodiment is the same as the configuration of transmission side apparatus 101 in the first embodiment shown in FIG. In the third embodiment, a UDP packet is used as a measurement packet.

  In the configuration of receiving side apparatus 105 in the third embodiment, reception rate calculating means 144 and achievable UDP throughput calculating means 145 are added to the configuration of receiving side apparatus 102 in the first embodiment shown in FIG. The transmission / reception means 140, the reception interval measurement means 141, and the usable bandwidth calculation means 142 of the reception side device 104 are the same as those in the first embodiment.

  The reception rate calculation unit 144 divides the packet size of each measurement packet stored in the measurement data storage unit 143 by the reception interval of each measurement packet measured by the reception interval measurement unit 141, thereby receiving the reception rate of each measurement packet. And the reception rate is stored in the measurement data storage unit 143.

  FIG. 11 is a diagram illustrating a data structure of measurement data according to the third embodiment. The measurement data storage unit 143 stores the measurement data in a structure as shown in FIG. 11, for example. In the example of FIG. 11, the reception rate of each measurement packet is added to the measurement data shown in FIG.

  The achievable UDP throughput calculation means 145 determines whether the reception rate is saturated by looking at the reception rates of the measurement packets stored in the measurement data storage means 143 in ascending order of the packet size of the measurement packets. to decide. When transmitting measurement packets in order from the smallest packet size to the largest packet size, it is determined whether the reception rate is saturated by looking at the reception rates in the order of the received measurement packets. Conversely, when transmitting measurement packets in order from the largest to the smallest packet size, the reception rates are viewed in the reverse order of the received measurement packets to determine whether the reception rate is saturated. Then, the reception rate when it is determined that the reception rate is saturated is set as a measurement value of the achievable UDP throughput.

  In order to determine whether or not the reception rate is saturated, for example, the reception rates are viewed in descending order of the packet size of the measurement packet, and compared with the reception rate of the previous measurement packet, and reception with respect to the packet size increment is performed. When the rate increment is equal to or less than a predetermined threshold, it is determined that the reception rate is saturated.

  FIG. 12 schematically shows a mechanism for calculating the achievable UDP throughput. FIG. 12A shows the transmission rate for the packet number. FIG. 12B shows the reception rate for the packet number. In FIG. 12, it is assumed that the packet size of the measurement packet is an even number sequence, and the measurement packets are transmitted at equal intervals. The transmission rate of each measurement packet in the transmission side device 104 increases linearly. Then, the reception rate of each measurement packet in the reception-side device 105 increases linearly with the transmission rate up to the middle. However, the increment of the reception rate gradually decreases after the measurement packet used to measure the available bandwidth and after the reception packet starts to widen. Then, if a measurement packet in which the reception rate is saturated and the increment value is equal to or less than a predetermined threshold value is specified, the value of the reception rate corresponding to the measurement packet becomes the measurement value of the achievable UDP throughput.

  Even if the packet size of the measurement packet is an even number sequence, if the packet is sent in order from the largest packet size to the smallest packet size, the reception rate should be determined in order from the smallest packet size to determine whether it is saturated. Good.

  Here, a generalization is considered when the packet size of the measurement packet is not an arithmetic sequence. If the horizontal axis in FIG. 12B is regarded as a packet size (proportional to), it can be considered that FIG. 12B is a plot in which reception rates are arranged in order from the smallest packet size. At that time, the interval in the horizontal axis direction of each point is an increase in the packet size. In this order, it can be seen that the reception rate can be determined to be saturated when the increase in the reception rate with respect to the increase in the packet size is equal to or less than a predetermined threshold value as compared with the reception rate of the previous measurement packet.

  Therefore, even when the packet size of the measurement packet is not an arithmetic progression, but increases or decreases exponentially, for example, saturation can be determined in the same manner as in the arithmetic progression. That is, when the reception rate is viewed in order from the measurement packet having the smallest packet size, it can be determined that the reception rate is saturated when the increase in the reception rate with respect to the increase in the packet size is equal to or less than a predetermined threshold. When the packet size is an arithmetic progression, the interval in the horizontal axis direction of each point is constant in proportion to the increase in the packet size, so it can be determined whether or not the point is saturated with the increase in the reception rate.

  FIG. 13 is a flowchart showing an example of the operation of achievable UDP throughput measurement according to the third embodiment. Steps S21 to S26 in FIG. 13 are the same as steps S11 to S16 in FIG. An explanation will be given from the point when it is determined that the available bandwidth has been calculated or the available bandwidth cannot be calculated.

  The reception rate calculation unit 144 divides the packet size of each measurement packet stored in the measurement data storage unit 143 by the reception interval of each measurement packet measured by the reception interval measurement unit 141, thereby receiving the reception rate of each measurement packet. And the reception rate is stored in the measurement data storage unit 143 (step S27). The achievable UDP throughput calculation unit 145 compares the reception rate of the previous measurement packet with respect to the reception rate of each measurement packet stored in the measurement data storage unit 143, and the increment of the reception rate becomes equal to or less than the specified threshold value. It is determined whether or not the increment of the reception rate is saturated (step S28). If it is determined that the increment of the reception rate is saturated (step S28; Y), the process proceeds to step S29, and if it is determined that it is not saturated (step S28; NO), the process proceeds to step S30.

  The achievable UDP throughput calculation means 145 identifies the measurement packet for which it was determined in step S28 that the increment of the reception rate is saturated, and determines the value of the reception rate corresponding to the measurement packet as the measurement value of the achievable UDP throughput. Then, the measurement value is returned to the transmission side device 104 (step S29).

  If it is determined that the reception rate is not saturated (step S28; NO), the achievable UDP throughput calculation means 145 determines whether the packet number of the measurement packet is N, that is, whether it is the final measurement packet. Is determined (step S30). When it is determined that the measurement packet number is not final (step S30; N), the process returns to step S27 to determine whether or not the increment of the reception rate of the next measurement packet is saturated. When the measurement packet is the last measurement packet of the packet train (step S30; Y), the fact that the achievable UDP throughput cannot be calculated is transmitted to the transmission side device 104 via the transmission / reception means 140 (step S31). ).

  FIG. 14 is a block diagram showing an example of a physical configuration of the transmission side apparatus or the reception side apparatus according to the embodiment of the present invention.

  As shown in FIG. 14, the transmission side devices 101 and 104 or the reception side devices 102 and 105 include a control unit 41, a main storage unit 42, an external storage unit 43, an operation unit 46, a display unit 47, and a transmission / reception unit 48. The main storage unit 42, the external storage unit 43, the operation unit 46, the display unit 47 and the transmission / reception unit 48 are all connected to the control unit 41 via the internal bus 40.

  The control unit 41 includes a CPU (Central Processing Unit) and the like, and executes processing for measuring available bandwidth or achievable UDP throughput according to a control program 44 or 45 stored in the external storage unit 43. The control program 44 is a program for executing processing of the transmission side devices 101 and 104. The control program 45 is a program for executing processing of the receiving side devices 102 and 105.

  The main storage unit 42 is configured by a RAM (Random-Access Memory) or the like, loads the control program 44 or 45 stored in the external storage unit 43, and is used as a work area of the control unit 41.

  The external storage unit 43 includes a nonvolatile memory such as a flash memory, a hard disk, a DVD-RAM (Digital Versatile Disc Random-Access Memory), a DVD-RW (Digital Versatile Disc ReWritable), and the processing described above is performed by the control unit 41. The control program 44 or 45 to be executed is stored in advance, and the data stored in the control program 44 or 45 is supplied to the control unit 41 in accordance with an instruction from the control unit 41, and the data supplied from the control unit 41 is supplied. Remember.

  The operation unit 46 includes a pointing device such as a keyboard and mouse, and an interface device that connects the keyboard and pointing device to the internal bus 40. Via the operation unit 46, the address of the partner device that performs the available bandwidth measurement or the achievable UDP throughput measurement, the initial value and the increment of the packet size of the measurement packet, and the like are input and supplied to the control unit 41.

  The display unit 47 is composed of a CRT (Cathode Ray Tube) or an LCD (Liquid Crystal Display), and displays the results of usable bandwidth measurement or achievable UDP throughput measurement.

  The transmitter / receiver 48 includes a wireless transmitter / receiver, a wireless modem or a network termination device, and a serial interface or a LAN (Local Area Network) interface connected thereto. The transmission side devices 101 and 104 and the reception side devices 102 and 105 communicate with each other by connecting to the IP network via the transmission / reception unit 48.

  The processing of the measurement packet generation means 110 and 130, the measurement packet transmission means 111 and 131, the transmission and reception means 112 and 132, and the parameter storage means 113 and 133 of the transmission side devices 101 and 104 is performed by the control program 44, the control unit 41, The processing is executed by using the storage unit 42, the external storage unit 43, the operation unit 46, the display unit 47, the transmission / reception unit 48, and the like as resources. In addition, the transmission / reception means 120 and 140, the reception interval measurement means 121 and 141, the available bandwidth calculation means 122 and 142, the measurement data storage means 123 and 143, the reception rate calculation means 144, and the achievable UDP throughput of the reception side devices 102 and 105 The processing of the calculation means 145 is executed by the control program 45 using the control unit 41, the main storage unit 42, the external storage unit 43, the operation unit 46, the display unit 47, the transmission / reception unit 48, and the like as resources.

  In addition, the above-described hardware configuration and flowchart are examples, and can be arbitrarily changed and modified.

  A central part that performs control processing including the control unit 41, the main storage unit 42, the external storage unit 43, the transmission / reception unit 48, the internal bus 40, and the like uses a normal computer system, not a dedicated system. It is feasible. For example, a computer program for executing the above operation is stored and distributed in a computer-readable recording medium (flexible disk, CD-ROM, DVD-ROM, etc.), and the computer program is installed in the computer. Thus, the transmission side devices 101 and 104 or the reception side devices 102 and 105 that execute the above-described processing may be configured. Further, the computer program is stored in a storage device included in a server device on a communication network such as the Internet, and the transmission side devices 101 and 104 or the reception side devices 102 and 105 are configured by downloading or the like by a normal computer system. May be.

  In addition, when the functions of the transmission side devices 101 and 104 or the reception side devices 102 and 105 are realized by sharing an OS (operating system) and an application program, or in cooperation with the OS and the application program, the application program part May be stored in a recording medium or a storage device.

  It is also possible to superimpose a computer program on a carrier wave and distribute it via a communication network. For example, the computer program may be posted on a bulletin board (BBS: Bulletin Board System) on a communication network, and the computer program may be distributed via the network. The computer program may be started and executed in the same manner as other application programs under the control of the OS, so that the above-described processing may be executed.

  Although the present invention has been described based on the preferred embodiments, the network bandwidth measurement system, the transmission side device, the reception side device, the method, and the program of the present invention are limited to the above embodiments. The present invention includes various modifications and changes made from the configuration of the above-described embodiment.

  A part or all of the above embodiment can be described as in the following supplementary notes, but is not limited thereto.

(Supplementary Note 1) Transmitting a plurality of measurement packets whose packet sizes sequentially increase or decrease at a predetermined transmission interval;
Receiving the transmitted measurement packet and measuring a reception interval of the measurement packet;
Comparing the transmission interval with the measured reception interval, calculating an available bandwidth using a measurement packet having a maximum packet size among measurement packets having the same reception interval and the transmission interval;
A network bandwidth measurement method comprising:

(Supplementary note 2) calculating a reception rate for each measurement packet by dividing the packet size for each measurement packet by the reception interval for each measurement packet measured by the reception interval measurement unit;
Judging whether the reception rate is saturated by looking at the reception rate in order from the smallest packet size of the measurement packet;
Calculating the achievable UDP throughput using the reception rate of the measurement packet when it is determined that the reception rate is saturated, in order from the smallest packet size of the measurement packet;
The network bandwidth measuring method according to claim 1, further comprising:

(Supplementary Note 3) In the step of determining whether or not the reception rate is saturated, the reception rate is compared with the reception rate of the previous measurement packet, in order from the smallest packet size of the measurement packet. The network bandwidth measuring method according to appendix 2, wherein when the increment of the reception rate with respect to the increment of the packet size is equal to or less than a predetermined threshold, it is determined that the reception rate is saturated.

(Supplementary Note 4) In the step of calculating the usable bandwidth, the usable bandwidth is calculated based on the packet size of the measurement packet having the largest packet size among the measurement packets having the same reception interval and transmission interval, and the transmission interval. The network bandwidth measuring method according to any one of appendices 1 to 3, wherein the network bandwidth measuring method is calculated.

(Supplementary note 5) The network bandwidth measuring method according to any one of supplementary notes 1 to 4, wherein in the step of transmitting the measurement packet, the plurality of measurement packets are transmitted at equal intervals.

(Supplementary note 6) The network bandwidth measurement method according to any one of supplementary notes 1 to 5, further comprising a step of generating a plurality of measurement packets whose packet sizes sequentially increase prior to the step of transmitting the measurement packet.

(Supplementary Note 7) In the step of calculating the usable bandwidth, the available bandwidth can be used based on the packet size of the measurement packet received immediately before the measurement packet whose reception interval is larger than the transmission interval and the transmission interval. The network bandwidth measuring method according to attachment 6, wherein the bandwidth is calculated.

(Supplementary Note 8) In the step of generating the measurement packet, the packet size of the first measurement packet is set to a predetermined minimum packet size, and the packet size of the second and subsequent measurement packets is set to be larger than the packet size of the previous measurement packet. The network bandwidth measuring method according to appendix 6 or 7, wherein a plurality of measurement packets having a packet size larger by a predetermined packet increase size is generated.

(Supplementary Note 9) In the step of generating the measurement packet, the packet size of the first measurement packet is set to a predetermined minimum packet size, and the packet size of the second and subsequent measurement packets is set to the packet size of the previous measurement packet. The network bandwidth measurement method according to appendix 6 or 7, wherein a plurality of measurement packets having an exponentially increasing packet size are generated.

(Supplementary note 10) The network bandwidth measurement method according to any one of supplementary notes 1 to 5, further comprising a step of generating a plurality of measurement packets whose packet sizes are sequentially reduced prior to the step of transmitting the measurement packet. .

(Supplementary note 11) In the step of calculating the usable bandwidth, the usable bandwidth is calculated based on a packet size of the first measurement packet in which the reception interval is equal to the transmission interval and the transmission interval. The network bandwidth measurement method described.

(Supplementary Note 12) In the step of generating the measurement packet, the packet size of the first measurement packet is set to a predetermined maximum packet size, and the packet size of the second and subsequent measurement packets is set to be larger than the packet size of the previous measurement packet. 12. The network bandwidth measuring method according to appendix 10 or 11, wherein a plurality of measurement packets having a packet size smaller by a predetermined packet reduction size is generated.

(Supplementary Note 13) In the step of generating the measurement packet, the packet size of the first measurement packet is set to a predetermined maximum packet size, and the packet size of the second and subsequent measurement packets is changed to the packet size of the previous measurement packet. The network bandwidth measurement method according to appendix 10 or 11, wherein a plurality of measurement packets having a packet size that decreases exponentially with respect to each other are generated.

(Supplementary Note 14) Measurement packet generation means for generating a plurality of measurement packets in which the packet size is sequentially increased or decreased;
Measurement packet transmission means for transmitting a plurality of measurement packets generated by the measurement packet generation means at a predetermined transmission interval;
A reception interval measuring means for receiving the transmitted measurement packet and measuring a reception interval of the measurement packet;
Available bandwidth calculation means for comparing the transmission interval with the measured reception interval and calculating an available bandwidth using a measurement packet having the largest packet size among the measurement packets having the same reception interval and the transmission interval. When,
A network bandwidth measurement system.

(Supplementary Note 15) A reception rate calculation unit that calculates the reception rate for each measurement packet by dividing the packet size for each measurement packet by the reception interval for each measurement packet measured by the reception interval measurement unit;
Saturation determination means for determining whether the reception rate is saturated by looking at the reception rate in order from the smallest packet size of the measurement packet;
Throughput calculating means for calculating the achievable UDP throughput using the reception rate when the saturation determination means determines that the reception rate is saturated;
The network bandwidth measurement system according to appendix 14, comprising:

(Supplementary Note 16) The saturation determination unit compares the reception rate with the reception rate of the previous measurement packet in order from the smallest packet size of the measurement packet, and compares the reception rate with respect to the increment of the packet size. The network bandwidth measurement system according to appendix 15, wherein the reception rate is determined to be saturated when the rate increment is equal to or less than a predetermined threshold.

(Supplementary Note 17) The available bandwidth calculating means may use the available bandwidth based on the packet size of the measurement packet having the largest packet size and the transmission interval among the measurement packets having the same reception interval and the transmission interval. The network bandwidth measuring system according to any one of appendices 14 to 16, which calculates

(Supplementary note 18) The network bandwidth measurement system according to any one of supplementary notes 14 to 17, wherein the measurement packet generation means increases or decreases the packet size exponentially.

(Supplementary Note 19) The measurement packet generation unit generates a measurement packet in which the packet size is sequentially increased,
The available bandwidth calculating means calculates an available bandwidth based on a packet size of a measurement packet received immediately before a measurement packet whose reception interval is larger than the transmission interval and the transmission interval. The network bandwidth measurement system according to any one of 14 to 18.

(Supplementary Note 20) The measurement packet generation unit generates a measurement packet in which the packet size is sequentially reduced,
The available bandwidth calculation means calculates the available bandwidth based on the packet size of the first measurement packet in which the reception interval is equal to the transmission interval and the transmission interval, according to any one of appendices 14 to 18. Network bandwidth measurement system.

(Supplementary Note 21) Measurement packet generation means for generating a plurality of measurement packets in which the packet size is sequentially increased or decreased;
Measurement packet transmission means for transmitting a plurality of measurement packets generated by the measurement packet generation means at a predetermined transmission interval;
A transmission-side device comprising:

(Supplementary Note 22) A reception interval measuring unit that receives a plurality of measurement packets that are sequentially increased or decreased in packet size, transmitted at a predetermined transmission interval, and measures a reception interval of the measurement packets;
The measurement packet transmission interval is compared with the measured reception interval, and the available bandwidth is calculated using the measurement packet having the largest packet size among the measurement packets having the same reception interval and the transmission interval. Bandwidth calculation means;
A receiving-side device.

(Supplementary note 23)
Processing to generate multiple measurement packets with increasing or decreasing packet size sequentially,
A process of transmitting the plurality of measurement packets at a predetermined transmission interval;
A program that executes

(Supplementary Note 24)
A process in which the packet size sequentially increases or decreases, receives a plurality of measurement packets transmitted at a predetermined transmission interval, and measures the reception interval of the measurement packets;
A process of comparing the transmission interval of the measurement packet with the measured reception interval, and calculating an available bandwidth using a measurement packet having a maximum packet size among measurement packets having the same reception interval and the transmission interval; ,
A program that executes

(Supplementary Note 25) A step of transmitting a plurality of measurement packets whose packet sizes are sequentially increased or decreased at a predetermined transmission interval;
Receiving the transmitted measurement packet and measuring a reception interval of the measurement packet;
Calculating the reception rate of each measurement packet by dividing the packet size of each measurement packet by the reception interval of each measurement packet measured by the reception interval measurement means;
Judging whether the reception rate is saturated by looking at the reception rate in order from the smallest packet size of the measurement packet;
Calculating the achievable UDP throughput using the reception rate of the measurement packet when it is determined that the reception rate is saturated, in order from the smallest packet size of the measurement packet;
A network bandwidth measurement method comprising:

(Supplementary note 26) In the step of determining whether or not the reception rate is saturated, the reception rate is compared with the reception rate of the previous measurement packet in the order from the smallest packet size of the measurement packet. 26. The network bandwidth measuring method according to appendix 25, wherein the reception rate is determined to be saturated when the increase in the reception rate with respect to the increase in the packet size is equal to or less than a predetermined threshold.

DESCRIPTION OF SYMBOLS 10 Transmission side apparatus 11 Measurement packet production | generation means 12 Measurement packet transmission means 20 Reception side apparatus 21 Reception interval measurement means 22 Available bandwidth calculation means 40 Internal bus 41 Control part 42 Main storage part 43 External storage part 44 Control program (Transmission side apparatus) )
45 Control program (receiving device)
46 operation unit 47 display unit 48 transmission / reception unit 101 transmission side device 102 reception side device 103 network 104 transmission side device 105 reception side device 106 network 110 measurement packet generation unit 111 measurement packet transmission unit 112 transmission / reception unit 113 parameter storage unit 120 transmission / reception unit 121 Reception interval measurement means 122 Available bandwidth calculation means 123 Measurement data storage means 130 Measurement packet generation means 131 Measurement packet transmission means 132 Transmission / reception means 133 Parameter storage means 140 Transmission / reception means 141 Reception interval measurement means 142 Available bandwidth calculation means 143 Measurement data storage Means 144 Reception rate calculation means 145 Achievable UDP throughput calculation means 150 Packet train at transmission 160 Packet train at reception

Claims (10)

Transmitting a plurality of measurement packets whose packet sizes sequentially increase or decrease at predetermined transmission intervals;
Receiving the transmitted measurement packet and measuring a reception interval of the measurement packet;
Comparing the transmission interval with the measured reception interval, calculating an available bandwidth using a measurement packet having a maximum packet size among measurement packets having the same reception interval and the transmission interval;
A network bandwidth measurement method comprising: Calculating a reception rate for each measurement packet by dividing the packet size for each measurement packet by the reception interval for each measurement packet measured by the reception interval measurement unit;
Judging whether the reception rate is saturated by looking at the reception rate in order from the smallest packet size of the measurement packet;
Calculating the achievable UDP throughput using the reception rate of the measurement packet when it is determined that the reception rate is saturated, in order from the smallest packet size of the measurement packet;
The network bandwidth measuring method according to claim 1, comprising:   In the step of determining whether or not the reception rate is saturated, the reception rate is compared with the reception rate of the previous measurement packet, in order from the smallest packet size of the measurement packet, and the packet size The network bandwidth measurement method according to claim 2, wherein the reception rate is determined to be saturated when the increase in the reception rate with respect to the increase is equal to or less than a predetermined threshold.   The step of calculating the available bandwidth calculates the available bandwidth based on the packet size of the measurement packet having the largest packet size among the measurement packets having the same reception interval and transmission interval, and the transmission interval. Item 4. The network bandwidth measuring method according to any one of Items 1 to 3. Measurement packet generation means for generating a plurality of measurement packets in which the packet size is sequentially increased or decreased;
Measurement packet transmission means for transmitting a plurality of measurement packets generated by the measurement packet generation means at a predetermined transmission interval;
A reception interval measuring means for receiving the transmitted measurement packet and measuring a reception interval of the measurement packet;
Available bandwidth calculation means for comparing the transmission interval with the measured reception interval and calculating an available bandwidth using a measurement packet having the largest packet size among the measurement packets having the same reception interval and the transmission interval. When,
A network bandwidth measurement system. Measurement packet generation means for generating a plurality of measurement packets in which the packet size is sequentially increased or decreased;
Measurement packet transmission means for transmitting a plurality of measurement packets generated by the measurement packet generation means at a predetermined transmission interval;
A transmission-side device comprising: A reception interval measuring means for receiving a plurality of measurement packets that are sequentially increased or decreased in packet size, transmitted at a predetermined transmission interval, and measuring a reception interval of the measurement packets;
The measurement packet transmission interval is compared with the measured reception interval, and the available bandwidth is calculated using the measurement packet having the largest packet size among the measurement packets having the same reception interval and the transmission interval. Bandwidth calculation means;
A receiving-side device. On the computer,
Processing to generate multiple measurement packets with increasing or decreasing packet size sequentially,
A process of transmitting the plurality of measurement packets at a predetermined transmission interval;
A program that executes On the computer,
A process in which the packet size sequentially increases or decreases, receives a plurality of measurement packets transmitted at a predetermined transmission interval, and measures the reception interval of the measurement packets;
A process of comparing the transmission interval of the measurement packet with the measured reception interval, and calculating an available bandwidth using a measurement packet having a maximum packet size among measurement packets having the same reception interval and the transmission interval; ,
A program that executes Transmitting a plurality of measurement packets whose packet sizes sequentially increase or decrease at predetermined transmission intervals;
Receiving the transmitted measurement packet and measuring a reception interval of the measurement packet;
Calculating the reception rate of each measurement packet by dividing the packet size of each measurement packet by the reception interval of each measurement packet measured by the reception interval measurement means;
Judging whether the reception rate is saturated by looking at the reception rate in order from the smallest packet size of the measurement packet;
Calculating the achievable UDP throughput using the reception rate of the measurement packet when it is determined that the reception rate is saturated, in order from the smallest packet size of the measurement packet;
A network bandwidth measurement method comprising:

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