Technical field
[0001]
　The present invention is, round trip delay time measuring system, the round trip delay time measuring method, return method, a communication apparatus, a program and a data structure.
Background technique
[0002]
　With the spread of services using the network, ensure the quality status of the network, service user there is an increasing demand to implement capital improvement of the network to take advantage of the comfortable service. Indicator to check the quality status of the network may include, for example, available bandwidth, round trip time, packet loss rate, and the fluctuation of the packet arrival interval.
[0003]
　Patent Document 1, a technique for confirming the available bandwidth of the network is disclosed. Specifically, according to the technique described in Patent Document 1, it transmits a plurality of measurement packets to gradually increase or decrease the packet size from the transmitting side (packet trains) at regular transmission intervals, transmission interval at the receiving end by comparing the reception interval and to estimate the available bandwidth. However, the index can be estimated by the technique described in Patent Document 1 is only available bandwidth, it is impossible to measure the round trip time.
[0004]
　Patent Document 2, a technique for calculating the available bandwidth and the round trip time utilized by reciprocating the packet train between two communication devices is disclosed. Further, Patent Document 3, the transmission time and the reception time measurement packet, and techniques for calculating a round trip time based on the transmission time and the reception time of the return packet is disclosed.
CITATION
Patent Document
[0005]
Patent Document 1: Japanese Laid-Open Patent Publication No. 2011-142622
Patent Document 2: Japanese Laid-Open Patent Publication No. 2002-199009
Patent Document 3: Japanese Laid-Open Patent Publication No. 2005-033499
Summary of the Invention
Problems that the Invention is to Solve
[0006]
　Generation timing of the packet train for use in backward in Patent Document 2 not specified. Therefore, when calculating the round trip time on the basis of the technique described in Patent Document 2, the delay time duration before sending a return packet train from receiving the forward packet train, the calculation result of the round trip time It would be included in the. The delay may include, for example, the time required for generating return packet trains, and the time required to identify the reception time.
　In other words, depending on the technique disclosed in Patent Document 2, there is a possibility that it is impossible to accurately calculate the round trip time.
[0007]
　According to the technique disclosed in Patent Document 3, to calculate a round trip time based on the transmission time and the reception time and the transmission time and the reception time of the return packet measurement packet. Therefore, the calculated round trip delay time does not include a delay time duration from the reception of the measurement packet before sending a return packet. However, according to the technique disclosed in Patent Document 3, the receiving terminal generates a return packet by appending the transmit time of the reception time and return packet measurement packet to the measurement packet received from the transmitting terminal. Therefore, the packet size is different between the measurement packet and return packet. That is, the transmitting terminal, so that the packet size in the forward path and the backward path is to measure the round-trip delay time based on different packets. Therefore, there is a possibility that it is impossible to accurately calculate the round trip time by the technique disclosed in Patent Document 3.
　An example of an object of the present invention is the round trip time measurement system that solves the problems described above, the round trip time measuring method, return method, communication device, program, and to provide a data structure.
Means for Solving the Problems
[0008]
　Round trip time measurement system according to the first aspect includes a first communication apparatus and a second communication device. The first communication device comprises a measurement packet transmitting unit that transmits the measurement packets to the first transmission time, information relating to the processing time indicating the time from the first reception time to the second sending time, and the measurement packet the reply packet with the same packet size and return packet receiver for receiving the second reception time, the time obtained by subtracting the processing time from the time from the first sending time to the second reception time and, and a delay time specifying unit which specifies a round trip time. Return packet the second communication device, to generate the a measurement packet receiving unit for the measurement packets are received by the first reception time, and processing time specifying unit for specifying the information relating to the processing time, the return packet a generating unit, as a reply to the measurement packet, and a return packet transmitter for transmitting the return packet to the second sending time.
[0009]
　Round trip time measuring method according to the second aspect, sends a measurement packet to the first transmission time, receives the measurement packets to the first reception time, the time from the first reception time to the second sending time identifying information relating to the processing time indicated, includes the information relating to the processing time, and the generated reply packet having the same packet size as measured packet, it said as a reply to the measurement packet, the return packet the second send to a transmission time, that receives the return packet to the second reception time, the time obtained by subtracting the processing time from the time from the first sending time to the second reception time is specified as round trip time a.
[0010]
　Communication device according to the third aspect, communicates with an external device. Communication device, a measurement packet transmitting unit that transmits the measurement packets to the first transmission time, a return packet transmitted by the external device to the second sending time as a response to the measurement packets, the measurement by the external device return packet received include information relating to the processing time indicating the time up to the second sending time from the first reception time a packet is received, and a return packet having the same packet size as the measurement packet to the second reception time comprising a receiving unit, the first transmission time period obtained by subtracting the processing time from the time until the second reception time from a delay time specifying unit which specifies a round trip time.
[0011]
　RTT measuring method according to the fourth embodiment transmits the measuring packet to the first transmission time, a return packet transmitted as a response to the measurement packet to the second sending time, the measurement packet is received the first includes information relating to the processing time indicating the time up to the second transmission time from the reception time, and receiving a reply packet having the same packet size as the measurement packet to the second reception time, the first transmission time and the time was Tokurae by subtracting the processing time from the time until the second reception time from having to identify the round trip time.
[0012]
　A program according to a fifth aspect of the computer, sends the measurement packet to the first transmission time, receives the measurement packets to the first reception time, indicating the time from the first reception time to the second sending time identifying information relating to the processing time, including the information relating to the processing time, and the generated reply packet having the same packet size as measured packet, it said as a reply to the measurement packet, the second transmission of the return packet was sent at time, run that receives the return packet to the second reception time, the time obtained by subtracting the processing time from the time from the first sending time to the second reception time is specified as round trip time make.
[0013]
　Communication apparatus according to a sixth aspect is the measurement packet used to calculate the round trip time and the measurement packet reception unit for receiving the first reception time, the processing time indicating the time up to the transmission time from the first reception time a processing time specifying unit for specifying the information relating, said process comprising the information time according, and the return packet generating unit that generates a reply packet having the same packet size as measurement packet as a response to said measurement packet, the comprising a return packet transmitting unit that transmits a return packet to the transmission time, the.
[0014]
　Return method according to a seventh aspect of the receives the measurement packet used to calculate the round trip time to the first reception time, to identify information related to the processing time indicating the time up to the transmission time from the first reception time includes the information relating to the processing time, and the generated reply packet having the same packet size as measurement packet as a response to the measurement packets comprises transmitting said return packet to said transmission time.
[0015]
　Program according to the eighth aspect causes a computer to receive a measurement packet used to calculate the round trip time to the first reception time, the information relating to the processing time indicating the time up to the transmission time from the first reception time identified, including the information relating to the processing time, and generates a reply packet having the same packet size as the measurement packet, a reply to the measurement packet to execute transmitting the return packet to the transmission time .
[0016]
　Data structure according to a ninth aspect is according the time of receiving the measurement packet used to calculate the round trip time, the until time to transmit a return packet used as a reply to the measurement packet, the processing time indicating a time including the information. Wherein the data structure has the same packet size as the measurement packet.
[0017]
　Data structure according to a tenth aspect of the transmission information according to the time of transmitting a measurement packet used to calculate the round trip time, from the time of receiving the measurement packet, a return packet used as a reply to the measurement packet and information time to, according to the processing time indicating the time to, the payload length of said measurement packet, by reducing the size of the information relating to the size and the processing time information according to the time for transmitting the return packet It comprises a payload portion and a padding data having the same size as obtained Rael size.
Effect of the Invention
[0018]
　According to at least one embodiment of the above aspect includes information return packet according to processing time indicating the time up to the transmission time of the return packet from the time of receiving the measurement packet, and the packet size of the return packet is measurement packet equal to the packet size. Accordingly, the communication device is able to accurately measure the round trip time.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019]
FIG. 1 is a schematic block diagram showing a basic structure of a round trip time measuring system according to an embodiment of the present invention.
It is a schematic block diagram showing a basic configuration of a first communication apparatus shown in FIG. 1; FIG.
Is a schematic block diagram showing the basic configuration of FIG. 3 the second communication apparatus shown in FIG.
It is a flowchart showing a schematic procedure of the RTT measuring method according to the embodiment of FIG. 4 the present invention.
5 is a diagram showing the network configuration of the quality status check system according to the first embodiment of the present invention.
6 is a diagram illustrating a transmission time of packet train according to the first embodiment.
7 is a diagram illustrating a reception time of packet train according to the first embodiment.
8 is a diagram showing an example of measurement data of the measurement packet according to the first embodiment.
9 is a diagram showing the data structure of the return packet according to the first embodiment.
10 is a diagram showing the transmission timing of the return packet according to the first embodiment.
11 is a flowchart showing an example of a quality status check operation according to the first embodiment.
12 is a block diagram illustrating a physical configuration of the first and second telecommunication devices according to at least one embodiment of the present invention.
DESCRIPTION OF THE INVENTION
[0020]
　Prior to description of specific embodiments, an outline of the embodiment.
　Figure 1 is a schematic block diagram showing a basic structure of a round trip time measurement system 1. Round trip time measurement system 1 includes a first communication device 10 and the second communication device 20. The first communication device 10 and the second communication device 20 are connected through a network 30.
[0021]
　Figure 2 is a schematic block diagram showing the basic configuration of the first communication device 10.
　The first communication device 10 includes a measurement packet sending unit 11, the return packet receiving unit 12 and the round trip time specifying unit 13,. Round trip time specifying unit 13, sometimes referred to simply as delay time specifying unit 13. Measurement packet transmitting unit 11 transmits the measurement packets. Return packet receiver 12, a return packet transmitted as a response to the measurement packets, the information relating to the processing time indicating the time from the time of receiving the measurement packet to return time to transmit a return packet to the measurement packet wherein, and receives a packet having the same packet size as measurement packets. Delay time specifying unit 13, a time obtained by subtracting the processing time from the time to the reception time of the return packet for measurement packet from the transmission time measurement packet, it identifies a round trip time.
[0022]
　Figure 3 is a schematic block diagram showing the basic configuration of the second communication device 20.
　Second communication device 20 comprises a measurement packet reception unit 21, the processing time specifying unit 22, the return packet generating unit 23, and a return packet transmitter 24. Measurement packet reception unit 21 receives the measurement packet. Processing time identifying unit 22 identifies the information relating to the processing time indicating the time up to the return time to transmit a return packet that is sent as a reply to the measurement packet from the time it receives the measurement packet. Return packet generator 23 generates a return packet for measurement packet. Return packet transmitter 24 transmits a return packet to return time.
[0023]
　Figure 4 is a flowchart showing a schematic procedure of the round trip time measurement method.
　First, the first communication device 10 transmits a measurement packet (step S1). Then, the second communication device 20 receives the measurement packet (step S2). Then, the second communication device 20 identifies the information relating to the processing time indicating the time from the time of receiving the measurement packet to return time to transmit a return packet to the measurement packet (step S3). Then, the second communication device 20, a return packet for measuring packet includes information relating to the processing time, and generates a packet having the same packet size as measured packet (step S4). Then, the second communication device 20 transmits a return packet to return time (step S5). Next, the first communication device 10 receives the return packet (step S6). The first communication device 10, the time obtained by subtracting the processing time from the time to the reception time of the return packet that is sent as a reply to the measurement packet from the transmission time measurement packet, identifies a round trip time (step S7).
[0024]
　Thus, it includes information return packet according to processing time indicating the time until the transmission time of the return packet from the time it receives the measurement packet, and the packet size of the return packet is equal to the packet size of the measuring packet. Accordingly, the first communication device 10 can accurately measure the round trip time.
[0025]
(First Embodiment)
　Hereinafter, with reference to the drawings will be described in detail embodiments.
　Figure 5 shows the network structure of the quality status check system 100 according to the first embodiment. Quality condition confirmation system 100 includes a first communication device 110 and a second communication device (external device) 120. Quality condition confirmation system 100 is an example of a round trip time measurement system.
　The first communication device 110 and the second communication device 120 are connected via a network 130. The network 130, the first communication device 110 and the second communication apparatus 120 other than the device (not shown) may be connected. May cross traffic flows between them (not shown) device.
[0026]
　The first communication device 110 and the second communication device 120 may be a personal computer (Personal Computer (PC)), a portable computer (Personal Digital Assistant (PDA)), a mobile phone, a smart phone, fixed telephone, street multimedia terminal, vehicle terminal, with the network connection function TV and network connection function set-top boxes, game consoles, network connection function printer, may be constituted by a communication device, such as a network connection function scanner.
[0027]
　First communication apparatus 110 includes a measurement packet generator 111, a measurement packet sending unit 112, receiving unit 113, the parameter storage unit 114 returns the packet receiving unit 115, and a delay time specifying unit 116. The second communication device 120 includes a transmitting and receiving unit 121, the measurement packet reception unit 122, the measurement data generating unit 123, the available bandwidth calculation unit 124, the measurement data storage unit 125, the return time determination unit 126, the processing time specifying unit 127, the return packet generating unit 128, and a return packet transmitting unit 129. Available bandwidth calculation unit 124 may simply referred to as calculator 124. Each part of the functions of the first communication device 110 and the second communication device 120 is, respectively, can be implemented by a computer operating according to a predetermined program.
[0028]
　Measurement packet generation unit 111 of the first communication device 110 generates a plurality of measurement packets to be transmitted to the second communication device 120. Measurement packet that is measured packet generating unit 111 generates, as a packet train is transmitted to the second communication device 120. Measurement packet generation unit 111, toward the first packet of the packet train to the last packet, generates a measurement packet that the packet size increases gradually. Transceiver 113, data transmission to network 130, and data received from the network 130 performs. Measurement packet transmission unit 112 via the transceiver unit 113 transmits the measurement packet with a predetermined transmission interval.
[0029]
　Parameter storage unit 114 stores the minimum packet size, and packet size increase, and a transmission interval of the measurement packet. Measurement packet generation unit 111 refers to the parameter storage unit 114, from the minimum packet size, it generates a measurement packet in increments packet size increase. Measurement packet transmitting unit 112 transmits the measurement packet with transmission interval stored in the parameter storage unit 114.
[0030]
　Minimum packet size, packet size increase, and the number of measurement packets constituting the packet train, a packet size of the measurement packets constituting the final packet, is set to fall within a range of packet sizes that can pass through the network 130 there. That is, the packet size of each measurement packets constituting the packet train are all set through the network 130 to a possible packet size reaches the second communication device 120.
[0031]
　Return packet receiving unit 115, via the transceiver unit 113 receives the return packet for measurement packet. Delay time specifying unit 116 specifies the round trip time on the basis of the return packet return packet receiving unit 115 has received. More specifically, the delay time specifying unit 116, the processing from the time from the transmission time of the measurement packet transmitted first to the reception time of the return packet, to the transmission time of the return packet from the reception time of the measurement packet transmitted first the time obtained by subtracting the time, specified as round trip time.
[0032]
　Transceiver 121 of the second communication device 120, the data transmission to network 130, and data received from the network 130 performs. Measurement packet receiving unit 122 receives the measurement packet in which the first communication device 110 via the transmission and reception unit 121 has transmitted. Measurement data generating unit 123, information about the measurement packet received (measurement data) is stored in the measurement data storage unit 125. Measurement data measured data generating unit 123 is stored in the measurement data storage unit 125 includes the receiving interval measurement packet measurement packet, transmission time measurement packet, and the reception time measurement packet. Measurement packet generation unit 111 is an example of a reception time specifying unit. Calculation unit 124, based on the measurement data of the measurement packet reception unit 121 has received, to calculate the available bandwidth. More specifically, the calculation unit 124 compares the reception interval of time measurement packet reception, and a transmission interval at the time of the measurement packet transmission. Calculation unit 124, among the receiving interval and the transmission interval are equal measurement packets, the packet size is calculated the available bandwidth using the maximum measurement packet. Calculation unit 124 calculates the available bandwidth, and stores the measurement data storage unit 125.
[0033]
　Return time determination unit 126 determines the time after the reception time measurement packet to the measurement data storage unit 125 has received the last to be stored, in the first transmission time of the return packet for measuring the packet received (return time). Processing time specifying unit 127, the reception time measurement packet received in the first the measurement data storage unit 125 stores the time to return time return time determination unit 126 is determined, according to the preparation of the transmission of the return packet processing to identify as time.
[0034]
　Return packet generation unit 128 generates a return packet to the first measurement packet received. Return packet generation unit 128, the return packet, the transmission time contained in the first measurement packet received, the processing time specifying unit 127 to include the processing time specified. In this case the return packet generation unit 128, calculation unit 124 may be further included the available bandwidth calculated the return packet. Return packet transmitter 129, a return packet is sent back packet generating unit 128 generates and transmits the return time return time determination unit 126 has determined.
[0035]
　Figure 6 is a diagram illustrating a transmission time of packet trains PTt. In FIG. 6, "PN" indicates the packet number. "PS" indicates the packet size. "Ti" indicates a transmission interval. Transmission time of packet trains PTt is a measurement packet train is transmitted from the first communication device 110. In the example shown in FIG. 6, the number of N measurement packet that is measured packet generating unit 111 generates (N is an integer of 3 or more) is set to. Packet number is a number for identifying the measurement packet. Transmission time of packet train, when configured by the measurement packet from aligned packet number 1 in series to N-th. Examples of each measurement packet includes IP (Internet Protocol) packets or UDP (User Datagram Protocol) packets and RTP (Real-time Transport Protocol) packets.
[0036]
　At the transmission time of packet trains PTt, the transmission interval of each measurement packet is equal to the transmission interval stored in the parameter storage unit 114. In other words, the time interval between adjacent measurement packet is equal. Packet size measurement packet of packet number 1 is equal to the minimum packet size that is stored in the parameter storage unit 114. Packet size measurement packet of the packet number 2, rather than the size of the measurement packet in the packet number 1, higher by packet increase size of the stored parameter storage unit 114. Later, the packet size of the measurement packets, each time a packet number that increased by one, incremented by the packet size increase minutes. Measurement packet generation unit 111, each measurement packet, a packet number, packet sizes, and include the transmission interval.
[0037]
　Figure 7 is a diagram illustrating a reception time of packet trains PTr. In FIG. 7, "PN" indicates the packet number. "PS" indicates the packet size. "Ri" represents the reception interval. When receiving a packet train PTr shows measurement packet train the second communication device 120 receives. Measurement packet train is transmitted through the network 130, as received at a packet train PTr, it is received by the second communication device 120. In the reception time of packet trains PTr, up to a certain point in time, receiving interval measurement packet is equal to the transmission interval at the time of the measurement packet transmission. However, when the packet size measurement packet becomes larger, at some point, the reception interval measurement packet is greater than the transmission interval at the time of transmission.
[0038]
　Calculation unit 124, when the reception interval measurement packet is greater than the transmission interval, to calculate the available bandwidth using the measurement packet sent to the previous of the measurement packet. That is, the calculation unit 124, the reception interval between a certain measurement packet and the measurement packet sent to the preceding that there measurement packet, when it becomes larger than the transmission interval of their Pakketto, 1 of a certain measurement packet calculating the available bandwidth using the measurement packet sent previously One. Packet size of the measurement packet is successively increased. Therefore, the measurement packets transmitted to the previous measurement packet reception interval is greater than the transmission interval, among the receiving interval and the transmission interval are equal measurement packets, packet size corresponds to the maximum of the measurement packet . Calculation unit 124, based on the packet size of the measurement packet sent to the previous measurement packet reception interval is greater than the transmission interval and the transmission interval to calculate the available bandwidth.
[0039]
　8 is a diagram showing an example of measurement data of the measurement packet. Measurement data storage unit 125 stores the measured data in the configuration example shown in FIG. Measurement data storage unit 125 stores a packet number of the measurement packet transmission and reception unit 121 receives, packet size, transmission interval, reception interval, transmission time, and the reception time. Measurement data generating unit 123, the transceiver unit 121 receives the measurement packets, the packet number included in the received measurement packet, the packet size, transmission interval, transmission time, and a reception time, respectively, of the measurement data storage unit 125 packet number, packet size, transmission interval, and stores the transmission time, and the reception time. Further, the measurement data generating unit 123, and the previous measurement packet reception time, obtains a reception interval measurement packet from the difference between the current measurement packet reception time, the reception interval calculated, the reception interval of the measurement data storage unit 125 Store.
　For example, the measurement data generating unit 123, the transceiver unit 121 receives the measurement packet of the packet number 3, the packet number included in the measurement packet, a packet size, transmission interval, transmission time, and a reception time, respectively, packet in the column of number 3, the packet number of the measurement data storage unit 125, stores the packet size, transmission interval, the transmission time, and the reception time. Further, the measurement data generating unit 123, reception and measurement packet reception time of the packet number 2, from the difference between the measurement packet reception time of the packet number 3 obtains the reception interval measurement packet of the packet number 3, it was determined the interval, in the column of the packet number 3 is stored in the reception interval of the measurement data storage unit 125.
[0040]
　Figure 9 is a diagram showing the data structure of the return packet according to the first embodiment. Examples of the return packet includes IP (Internet Protocol) packets or UDP (User Datagram Protocol) packets and RTP (Real-time Transport Protocol) packets.
　Return packet is configured from a header portion and a payload portion and ( "PL" in FIG. 9 shows a payload portion). The header portion, source, destination, and stores including the size of the packet, and information about other return packet. Header size of the measurement packets is the same as the return packet.
　The payload portion is constituted from a transmission time of the measurement packet that is included in the measurement packet, a processing time is the processing time specifying unit 127 specified, the padding data (dummy data). Padding data is data that is stored to match the packet size of the return packet with the packet size of the measuring packet. In other words, the size of the padding data from the payload length of the measurement packet is obtained by subtracting the size of the data indicating the processing time size and processing time of the data identification unit 127 indicating the transmission time of the measurement packet has a specific size be equivalent to. Padding data may be data having no meaning (e.g., may be a data "0" is enumerated). Some of the padding data, calculator 124 may be included back packets available bandwidth calculated. In this case, the first communication device 110, by receiving the return packet, it is possible to recognize the available bandwidth of the network 130.
[0041]
　Figure 10 is a diagram showing the transmission timing of the return packet according to the first embodiment. Return packet is a packet in which the first communication device 110 is returned against the measurement packet that is transmitted first. As described above, the second communication device 120, after receiving the measurement packet by the first communication device 110 has transmitted last, sends a return packet. First transmission time t measurement packet s from reception time t of the return packet s_now time to time T s expressed as. Time T s , the addition to the round trip time of the network 130 by the measurement packet and return packet, the time t receives the first measurement packet r from time t to transmit a return packet r_now processing according to the second communication device 120 to time T R are included. Accordingly, the first communication device 110, the time T s time T since r by subtracting, it is possible to obtain the round trip delay time does not include the processing time by the second communication device 120.
[0042]
　Figure 11 is a flow chart showing an example of the quality status check operation according to the first embodiment. Measurement packet generation unit 111 generates N measurement packets constituting the packet train (step S101). Measurement packet generation unit 111 sets a packet size measurement packet of the packet number 1 is the head of a packet train to a minimum packet size for storing the parameter storage unit 114 (size of the packet having the smallest size). Measurement packet generation unit 111, every time the packet number is to increase one packet size measurement packet, the parameter storage unit 114 is increased by a packet size increase minutes of storing. Generalizing, measurement packet generation unit 111, i-th (i = 1,2,3, ···, N ) the packet size of the measuring packet is represented by the following equation.
　Packet size = minimum packet size + (i-1) × packet size increase
　measurement packet generation unit 111, each measurement packet, and packet number, and the packet size, transmission time, a transmission interval stored in the parameter storage unit 114 include.
[0043]
　Measurement packet transmission unit 112 via the transceiver unit 113, the measurement packet that is measured packet generating unit 111 generates, sequentially transmitted to the second communication device 120 one by one (step S102). At that time, the measurement packet transmitting unit 112, the spacing between successive measurement packets, so that the transmission interval stored in the parameter storage unit 114, transmits each measurement packet sequentially. Measurement packet transmitting unit 112 according to the packet number, packet number 1, packet number 2, ..., in order of packet number N th, to the measurement packet of the packet number N th transmits each measurement packet at regular intervals . Measurement packet transmitted from the first communication device 110 through the network 130, is received at the second communication device 120.
[0044]
　Measurement packet reception unit 122 of the second communication device 120 receives the measurement packet via the transmitting and receiving unit 121 (step S103). Measurement data generating unit 123, the measurement packet reception unit 122 receives the measurement packets, the packet number included in the received measurement packet, the packet size, transmission interval, and the transmission time, measurement data storage section 125 (see FIG. 8 and stores it in). The measured data generating unit 123 identifies the reception time measurement packet, and stores the measurement data storage unit 125. Further, the measurement data generating section 123 with respect to second and subsequent measurement packet, and the reception time of the measurement packet, determined as a reception interval the difference between the reception time of the previous measurement packet, the measurement data storage unit 125 Store. Calculation unit 124, each time the transmitting and receiving unit 121 receives the measurement packet and checks the reception interval measurement packet, the size relationship between the transmission interval included in the measurement packet (step S104).
[0045]
　The transmission time of packet trains (see Fig. 6), the size of the measuring packet is gradually increased, the data amount per unit time of a packet which the first communication device 110 is transmitted to the second communication device 120 is gradually increases in. Increased amount of data per unit time, when the first communication device 110 exceeds the available bandwidth of the communication path to the second communication device 120, the received measurement packet received by the second communication device 120 interval is greater than the transmission interval at the time of the measurement packet transmission. Therefore, calculation unit 124, the receiving interval measurement packet in step S104 is determined to be larger than the transmission interval: Based on (step S104 YES), the transmission interval and packet size of the measuring packet, calculates the available bandwidth (step S105).
[0046]
　More specifically, the calculation unit 124 calculates the available bandwidth by the following procedure at step S105. Calculation unit 124, first, the reception interval is checked packet number measurement packet that is larger than the transmission interval. Reception interval and "j" packet number when larger than the transmission interval. Then, calculating unit 124, a measurement data storage unit 125, a packet number to obtain the transmission interval and packet size j-1 th measurement packet. Thereafter, the calculation unit 124 uses the following equation to calculate the available bandwidth.
　Available bandwidth = (packet size j-1 th measurement packet) / transmission interval
[0047]
　Then, the second communication device 120, the packet number of measurement packets, determines whether N number (step S106). The second communication device 120, when the measured packet number in step S106 is determined not to be numbered N (step S106: NO), the process returns to step S103, to receive the next measurement packet.
[0048]
　On the other hand, the calculation unit 124, the receiving interval measurement packet in step S104 is determined to be equal to or less than the transmission interval (step S104: NO), the packet number of measurement packets, determines whether N number (step S107). The second communication device 120, when the measured packet number in step S107 is determined not to be numbered N (step S107: NO), the process returns to step S103, to receive the next measurement packet. On the other hand, the calculation unit 124, when the measurement packet number is determined to be number N in step S107 (step S107: YES), that is, when the received measurement packet is a last measurement packet of the packet train, use available bandwidth to identify that it is impossible calculated (step S108).
[0049]
　When the second communication device 120 a packet number is received measurement packet of number N (step S106: YES, Step S107: YES), the return time determination unit 126, after the current time time, that the packet train last a predetermined time after the reception time measurement packet, determines the return time of transmitting the return packet (step S109). For example, the return time determination unit 126, the time at which the return packet generating unit 128 is added to the current time the time required to generate a return packet, to determine the return time.
[0050]
　Then, the processing time specifying unit 127, the time until the measurement data storage unit 125 back time back from the reception time (see FIG. 8) is stored in association with the first measurement packet time determination unit 126 is determined, processing time It identified as (step S110). Then, the return packet generating unit 128, a transmission time measurement data storage section 125 (see FIG. 8) is stored in association with the first measurement packet, and processing time is the processing time specifying unit 127 specified, the padding data comprising generating a return packet (step S111). Return packet generation unit 128, the measurement data storage unit 125 reads the packet size (see FIG. 8), the size of the header portion from the packet size, by subtracting the size of the transmission time measurement packet, and the size of the processing time , to identify the size of the padding data. The return packet generation unit 128, to include information of the available bandwidth calculation unit 124 in a part of the padding data is calculated. The area of the information of the available bandwidth, that available calculation unit 124 has calculated bandwidth or available bandwidth is not calculated is stored.
　Return packet transmitter 129 transmits the return packet is sent back packet generating unit 128 has generated, to the first communication device 110 via the transceiver unit 121 (step S112).
　Measurement packet transmitted from the second communication device 120 through the network 130, is received at the first communication device 110.
[0051]
　Return packet receiving unit 115 of the first communication device 110 receives the return packet through the transmitting and receiving unit 113 (step S113). Delay time specifying unit 116, a transmission time and processing time of the measurement packet that is included in the return packet received, based on the reception time of the return packet, to identify the round trip time (step S114). More specifically, the delay time specifying unit 116 specifies the reception time of the return packet received, calculates the time from the transmission time of the measurement packet that is included in the return packet to its reception time.
　Then the delay time specifying unit 116, the calculated time, by subtracting the processing time included in the return packet, to identify the round trip time. The first communication device 110 can by the information of the available bandwidth that is included in the return packet padding data, recognizes the available bandwidth of the network 130.
[0052]
　In this embodiment, the return packet includes information relating to the processing time indicating the time until the transmission time of the return packet from the time it receives the measurement packet. Furthermore, the packet size of the return packet is equal to the packet size of the measuring packet. Accordingly, the first communication device 110 is able to accurately measure the round trip time.
[0053]
　Further, in this embodiment, by including the information available to the return packet band, serving as a packet for notification of available bandwidth packet for measuring round-trip delay time is the second communication device 120 sends. Thus, the quality status check system 100, a small number of communications, it is possible to recognize the available bandwidth and the round trip time of the network 130 to the first communication device 110. The timing of generating a return packet in this embodiment is a post-calculation of the available bandwidth by the calculation unit 124. Thus, the second communication device 120 can generate a return packet so as not to affect the check of the available bandwidth.
[0054]
　Having thus described in detail embodiments of the present invention with reference to the drawings, specific configurations are not limited to the above embodiment, it is possible to make various design changes or the like.
　For example, in the embodiment described above, the quality status check system 100 is to identify the round trip time on the basis of the return packet for the first measurement packet, an embodiment of the present invention is not limited thereto. For example, in other embodiments, the second communication device 120 and the last measurement packet, and transmit the return packet to other measurement packet (measurement packet other than the first measurement packet) to the first communication device 110 good.
[0055]
　Packet train according to the embodiment described above is comprised of a plurality of measurement packets that the packet size increases sequentially, embodiments of the present invention is not limited thereto. For example, a packet train according to another embodiment, the packet size may be composed of a plurality of measurement packets that decreases sequentially.
[0056]
　In the embodiment described above, the quality status check system 100 identifies the available bandwidth and the round trip time of the network 130, embodiments of the present invention is not limited thereto. For example, the quality status check system 100 according to another embodiment, without specifying the available bandwidth of the network 130, may identify the round trip delay time only. In this case, the first communication device 110 may not transmit the measurement packet as a packet train.
[0057]
　In the embodiment described above, the return packet (T in Fig. 10 processing time r has been described to be stored as the information relating to the processing time), For example, in other embodiments, the reception time of the return packet measurement packets (t in FIG. 10 r and the transmission time of the return packet) (t in FIG. 10 R_now combinations) be stored as the information relating to the processing time good.
　In the embodiment described above, but the return packet has been described for the case of storing the transmission time measurement packet, an embodiment of the present invention is not limited thereto. For example, in other embodiments, if the first communication device 110 stores the transmission time of each measurement packet by returning a packet to store the number of the measurement packet in place of the transmission time measurement packet, the 1 of the communication device 110 can calculate the round trip time. Further, if the previously determined whether a return packet is sent back to any of the measurement packet in advance, that is return packet may not be stored even the number of measurement packets.
[0058]
　Figure 12 is a block diagram illustrating a physical configuration of the first communication device 110 and the second communication device 120 according to at least one embodiment.
[0059]
　The first communication device 110 and the second communication device 120, as shown in FIG. 12, a control unit 41, main memory 42, external storage unit 43, operation unit 44, display unit 45 and the transceiver 46. The main memory unit 42, external storage unit 43, operation unit 44, display unit 45 and the transmitting and receiving unit 46 is connected to the control unit 41 via the internal bus 40 either.
[0060]
　The control unit 41 is a CPU (Central Processing Unit) or the like. Control unit 41 according to the control program stored in the external storage unit 43, executes the processing for the delay time specified or available bandwidth measurement. Main storage unit 42 is composed of RAM (Random-Access Memory) or the like. Main storage unit 42 loads a control program stored in the external storage unit 43 is used as a work area of ​​the control unit 41.
[0061]
　The external storage unit 43 is a flash memory, a hard disk, DVD-RAM (Digital Versatile Disc Random-Access Memory), and a nonvolatile memory such as DVD-RW (Digital Versatile Disc ReWritable). The external storage unit 43 pre-stores a control program for causing the above-described processing in the control unit 41, also, according to an instruction from the control unit 41 supplies the data stored in the control program in the control unit 41, storing data supplied from the control unit 41.
[0062]
　Operation unit 44 includes a pointing device such as a keyboard and a mouse, and a interface device for connecting a pointing device such as an internal bus 40. Via the operation unit 44, the address of the remote device performing a delay time specific or available bandwidth measurement, such as increase the initial value of the packet size of the measuring packet is input, is supplied to the control unit 41.
[0063]
　Display 45 is comprised of a CRT (Cathode Ray Tube) or LCD (Liquid Crystal Display). Display unit 45 displays a result of the delay time specified or available bandwidth measurement.
[0064]
　Transceiver 46, wireless transceiver, and a serial interface or a LAN (Local Area Network) interface for connecting a wireless modem or network terminal equipment, and with them. The first communication device 110 and the second communication device 120 is connected to the IP network via the transceiver unit 46 communicates with each other.
[0065]
　Other hardware configuration and flowcharts above is an example, that variations and modifications are possible arbitrarily.
[0066]
　Control unit 41, main memory 42, the portion about which performs constituted control process from an external storage unit 43, transceiver 46 and the internal bus 40 is not only by a dedicated system, using a normal computer system it is possible to realize. For example, installing the computer program for performing the operation, the computer-readable recording medium (flexible disk, CD-ROM, DVD-ROM, etc.) and distributed and stored in, the computer program in the computer the may form a first communication device 110 or the second communication device 120 to perform the above processing. The configuration of the first communication device 110 or the second communication device 120 storage device in advance and stores the computer program, the normal computer system by downloading or the like of a server device over a communication network such as the Internet it may be.
[0067]
　Also, the functions of the first communication device 110 or the second communication device 120, for example, to realize in cooperation with an OS (operating system) sharing application program, or an OS and an application program, the application program portion only it may be stored in a recording medium or a storage device.
[0068]
　Further, by superimposing the computer program on a carrier wave, it can be distributed via a communication network. For example, bulletin board over the communication network (BBS: Bulletin Board System) to posted above computer program, via the network may distribute the computer program. Then, start the computer program under the control of the OS, by performing similarly to other application programs may be configured to run the process.
[0069]
　While there have been shown and described present invention by referring to the embodiments, the present invention is not limited to above embodiments. Those skilled in the art without departing from the scope of the invention defined by the claims, will be able to configure and details various modifications are understood.
[0070]
　Some or all of the above embodiments, can be described as the following notes, not limited to the following.
[0071]
(Supplementary Note 1)
　first communication apparatus and a second communication device,
　the first communication device,
　a measurement packet transmitting unit that transmits the measurement packets to the first transmission time,
　the second from the first reception time includes information related to the process time indicating the time up to the transmission time, and said a return packet receiving unit that receives a reply packet to the second reception time with the same packet size as measurement packets,
　the second from the first transmission time from time to the reception time period obtained by subtracting the processing time, and a delay time specifying unit which specifies as the round trip time,
　the second communication device,
　the first receiving the measurement packet a measurement packet receiving section for receiving the time,
　the processing time specifying unit for specifying the information relating to the processing time,
　and sends back a packet generation unit that generates the return packet,
　against the measurement packet As replies and a return packet transmitter for transmitting the return packet to the second sending time
　RTT measurement system.
[0072]
(Note 2)
　the measurement packet transmission stage transmits a plurality of measurement packets packet size increases or decreases sequentially,
　the second communication device, receiving the measurement packet and the transmission interval of the plurality of measurement packets comparing the interval, it said among the transmission interval and said receiving interval is equal measurement packets, comprises a calculation unit which packet size to calculate the available bandwidth using the maximum measurement packet
　round trip time according to Appendix 1 measurement system.
[0073]
(Supplementary Note 3)
　the second communication device,
　the return time is the time for transmitting the return packet, the return time determination unit for determining the end time after the time of receiving the measurement packet of the plurality of measurement packets It provided
　round trip time measuring system according to Appendix 2.
[0074]
(Supplementary Note 4)
　The return packet generating unit generates the return packet including the available bandwidth where the calculation unit has calculated
　round trip delay time measuring system according to Appendix 2 or Appendix 3.
[0075]
(Supplementary Note 5)
　sends the measurement packet to the first transmission time,
　wherein the received measurement packet to the first reception time,
　and specifying the information relating to the processing time indicating the time from the first reception time to the second sending time ,
　wherein the information relating to the processing time, and the generated reply packet having the same packet size as measurement packet
　as a response to said measurement packet, transmits the return packet to the second sending time,
　the return packet the received second reception time,
　the time obtained by subtracting the processing time from the time from the first sending time to the second reception time, specified as the round trip time
　RTT measurement method having the.
[0076]
(Supplementary Note 6)
　A communication apparatus for communicating with an external device,
　the measurement packet and the measurement packet transmitting unit that transmits the first transmission time,
　is transmitted to the second transmission time as a response to the measurement packet by the external device a return packet includes information relating to the processing time indicating the time from the first received time of the measurement packet is received by the external device to said second transmission time, and have the same packet size as the measurement packet a return packet receiver for receiving a return packet to the second reception time,
　the time obtained by subtracting the processing time from the time from the first sending time to the second reception time is specified as round trip time a delay time specifying unit
　communication apparatus comprising a.
[0077]
(Supplementary Note 7)
　sends the measurement packet to the first sending time,
　the measurement packet a return packet transmitted to the second transmission time as a reply to the measurement from said first reception time at which the packet was received second includes information relating to the processing time indicating the time up to the transmission time, and the reply packet with the same packet size as measured packet received in the second reception time,
　the time from the first sending time to the second reception time the time was Tokurae by reducing the processing time is specified as the round trip time from the
　round trip delay time measuring method with the.
[0078]
(Supplementary Note 8)
　to the computer,
　sends the measurement packet to the first transmission time,
　receives the measurement packets to the first reception time,
　according to the first processing indicates the time from the reception time to the second sending time time information identify,
　wherein said information relating to the processing time, and generates a reply packet having the same packet size as the measurement packet,
　a reply to the measurement packet, transmits the return packet to the second sending time,
　receiving said return packet to the second reception time,
　the time obtained by subtracting the processing time from the time from the first sending time to the second reception time is specified as round trip time
　program for executing that.
[0079]
(Supplementary Note 9)
　round trip delay and measurement packet reception unit which receives the measurement packets to the first reception time used to calculate the time,
　processing for identifying the information relating to the processing time indicating the time up to the transmission time from the first reception time and time specifying unit,
　wherein said information relating to the processing time, and a return packet generator that generates a reply packet having the same packet size as the measurement packet,
　a reply to the measurement packet, the transmission time of the return packet a return packet transmitter for transmitting to the
　communication device comprising a.
[0080]
(Supplementary Note 10)
　receives the measurement packet used to calculate the round trip time to the first reception time,
　to identify information related to the processing time indicating the time up to the transmission time from the first reception time,
　according to the processing time includes the information, and the generated reply packet having the same packet size as measurement packet
　as a response to said measurement packet, it transmits the return packet to the transmission time
　back method having the.
[0081]
(Supplementary Note 11)
　to a computer,
　receives the measurement packet used to calculate the round trip time to the first reception time,
　to identify information related to the processing time indicating the time up to the transmission time from the first reception time,
　the processing wherein the information relating to time, and wherein generating the reply packet with the same packet size as measurement packet
　as a response to said measurement packet, transmits the return packet to the transmission time
　program for executing that.
[0082]
(Supplementary Note 12)
　A data structure,
　according the time of receiving the measurement packet used to calculate the round trip time, the until time to transmit a return packet used as a reply to the measurement packet, the processing time indicating a time includes information,
　the data structure has the same packet size as the measurement packet
　data structure.
[0083]
(Supplementary Note 13)
　and information relating to the time of transmitting a measurement packet used to calculate the round trip time,
　from the time of receiving the measurement packet, and the time to transmit a return packet used as a reply to the measurement packet, the time and information relating to the processing time indicating a
　payload length of said measurement packet, the same as obtained Rael size by subtracting the size of the information relating to the size and the processing time information according to the time for transmitting the return packet and padding data having a size
　data structure comprising a payload portion having a.
[0084]
　This application claims priority based on 2014 November Japanese Patent Application 2014-234691, filed in 19 days, the entire disclosure of which is incorporated herein.
Industrial Applicability
[0085]
　The present invention is, round trip delay time measuring system, the round trip delay time measuring method, return method, a communication device, a program, and may be applied to the data structure.
DESCRIPTION OF SYMBOLS
[0086]
　1 round trip time measuring system
　100 quality status check system
　10, 110 the first communications device
　11,112 measurement packet sending unit
　12,115 return packet receiver
　13,116 round trip time specifying unit
　20, 120 the second communication device
　21 , 122 measurement packet reception unit
　22,127 processing time specifying unit
　23,128 return packet generator
　24,129 return packet transmitter
　30 and 130 network

The scope of the claims
[Claim 1]
　Comprising a first communication apparatus and a second communication device,
　the first communication device,
　a measurement packet transmitting unit that transmits the measurement packets to the first transmission time,
　from the first reception time to the second sending time includes information relating to the processing time indicating the time, and the return packet receiving unit that receives a reply packet having the same packet size as the measurement packet to the second reception time,
　from the first sending time to the second reception time the time obtained by subtracting the processing time from a time, and a delay time specifying unit which specifies as the round trip time,
　the second communication device,
　receives the measurement packets to the first reception time a measurement packet receiving unit,
　and a processing time specifying unit for specifying the information relating to the processing time,
　and sends back a packet generation unit that generates the return packet,
　the reply to the measurement packet , And a return packet transmitter for transmitting the return packet to the second sending time
　RTT measurement system.
[Claim 2]
　Sends a measurement packet to the first transmission time,
　wherein the received measurement packet to the first reception time,
　and specifying the information relating to the processing time indicating the time from the first reception time to the second sending time,
　the processing time wherein said information relating to, and the generated reply packet having the same packet size as measurement packet
　as a response to said measurement packet, transmits the return packet to the second sending time,
　the return packet second receiver received time,
　the time obtained by subtracting the processing time from the time from the first sending time to the second reception time, specified as the round trip time
　RTT measurement method having the.
[Claim 3]
　A communication device that communicates with an external device,
　the measurement packet and the measurement packet transmitting section that transmits the first transmission time,
　there in return packet transmitted to the second transmission time as a response to the measurement packet by the external device Te, a return packet said includes external device by according to the process time indicating the time from the first reception time the measurement packet is received until the second transmission time information and having the same packet size as the measurement packet first a return packet receiver for receiving the second reception time,
　the time obtained by subtracting the processing time from the time until the second reception time from the first transmission time, the delay time specifying unit which specifies a round trip time DOO
　communication device comprising a.
[Claim 4]
　Sends a measurement packet to the first transmission time,
　a return packet transmitted as a reply to the second sending time for said measurement packet, from a first reception time the measurement packet is received until the second transmission time includes information relating to the processing time indicating the time, and receives a reply packet having the same packet size as the measurement packet to the second reception time,
　the processing time from the time from the first sending time to the second reception time the time was Tokurae by subtracting, specified as the round trip time
　RTT measurement method having the.
[Claim 5]
　The computer
　sends the measurement packet to the first transmission time,
　wherein the received measurement packet to the first reception time,
　and specifying the information relating to processing time indicating the time from the first reception time to a second transmission time,
　wherein said information relating to the processing time, and the generated reply packet having the same packet size as measurement packet
　as a response to said measurement packet, transmits the return packet to the second sending time,
　the return packet receiving the second reception time,
　the time obtained by subtracting the processing time from the time from the first sending time to the second reception time is specified as round trip time
　program for executing that.
[Claim 6]
　A measurement packet reception unit for receiving the measurement packet used to calculate the round trip time to the first reception time,
　and processing time specifying unit for specifying the information relating to the processing time indicating the time up to the transmission time from the first reception time ,
　wherein the information related to the treatment time, and a return packet generator that generates a reply packet having the same packet size as the measurement packet,
　a reply to the measurement packet sent back to transmitting the return packet to the transmission time a packet transmitter
　communication device comprising a.
[Claim 7]
　Receiving a measurement packet used to calculate the round trip time to the first reception time,
　to identify information related to the processing time indicating the time up to the transmission time from the first reception time,
　wherein the information relating to the processing time and wherein generating the reply packet with the same packet size as measurement packet
　as a response to said measurement packet, it transmits the return packet to the transmission time
　back method having the.
[8.]
　The computer
　receives the measurement packet used to calculate the round trip time to the first reception time,
　to identify information related to the processing time indicating the time up to the transmission time from the first reception time,
　according to the processing time the It includes information and the generated reply packet having the same packet size as measurement packet
　as a response to said measurement packet, transmits the return packet to the transmission time
　program for executing that.
[Claim 9]
　A data structure,
　comprising the time of receiving the measurement packet used to calculate the round trip time, until the time to transmit a return packet used as a reply to the measurement packet, the information relating to the processing time indicating a time,
　wherein the data structure has the same packet size as the measurement packet
　data structure.
[Claim 10]
　And information relating to the time of transmitting a measurement packet used to calculate the round trip time,
　from said time of receiving the measurement packet, the relative measurement packet to the time to transmit a return packet used as a reply, the processing time indicating a time and information relating to
　the padding with the payload length of said measurement packet, the same size as the resulting Rael size by subtracting the size of the information relating to the size and the processing time information according to the time for transmitting the return packet and data
　data structure comprising a payload portion having a.