JP3753704B2 - Communication quality measuring apparatus and method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a technique for measuring traffic for a packet flow flowing on a network for packet communication. In particular, the present invention relates to a technique for measuring traffic at short time intervals and grasping communication quality.
[0002]
[Prior art]
The conventional communication quality measuring device for packet communication is intended to measure the communication quality at the network level, and it can measure the traffic volume of the entire line, the protocol, and the traffic volume by layer for a long time. Has been provided as the main function.
[0003]
However, with the conventional method described above, it is impossible to identify the packet flow generated by an application that uses the network, analyze the effect of the packet flow on the network, and measure the communication quality required to cope with it. Met.
[0004]
That is, since the conventional communication quality measuring device is intended for long-term measurement of traffic volume, the time resolution of traffic is targeted for 1 second or more. For this reason, it was impossible to grasp the traffic characteristics of a specific application such as a streaming service.
[0005]
The bandwidth required for a network by an image or audio streaming service depends on the coding method, and is discussed in terms of an average bandwidth per second. However, software that transmits the encoded information to the network performs a data transmission process independently of the encoding process. In addition, the operation cycle of software depends on the time unit of the task management system of the operating system in which it is executed, and is generally several milliseconds to several tens of milliseconds. In other words, traffic transition measurement with higher time resolution is required for quality control of streaming data sent to the network.
[0006]
[Non-Patent Document 1]
Kihong Park, “ON THE EFFECT AND CONTROL OF SELF-SIMILAR NETWORK TRAFFIC: S SIMULATION PERSPECTIVE”, Proceedings of the 1997 Winter Simulation Conference, pp.989-996
[0007]
[Problems to be solved by the invention]
The problem to be solved by the present invention is to provide a technology that enables measurement of traffic volume with high temporal resolution.
[0008]
[Means for Solving the Problems]
The purpose of this is to integrate the packet length of packets having predetermined header information with respect to the packets that are sequentially input to the measuring device, and to accumulate the accumulated value in the accumulating unit, at a predetermined time interval. The problem is solved by providing an integrated value reading unit that reads and outputs the integrated value from the storage unit.
[0009]
According to the present invention, since the integrated value is accumulated and read out at a predetermined time interval, the traffic amount can be measured with high time resolution by shortening the reading time interval (1 second or less). It can be done in time. On the other hand, in the prior art, a large amount of packet data is stored and processed in the measurement apparatus, and therefore, it is not possible to measure the traffic volume with high time resolution in real time.
[0010]
Further, by initializing the value stored in the storage unit every time the integrated value is read from the storage unit at the time interval, the difference calculation is not required, and high-speed processing is possible.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
As an embodiment of the present invention, a communication quality measuring apparatus capable of measuring a traffic amount per unit time of a packet flow at a time interval of 1 second or less will be described. In describing this communication quality measuring apparatus, first, the reason for setting the measurement time interval to 1 second or less, more specifically, 10 μsec or more and 1 second or less will be described in detail.
[0012]
An application that performs real-time transfer of moving images and audio requires a time constraint of 1 second or less, unlike a general application in which processing timeout is determined in seconds.
[0013]
An example of real-time transfer of a moving image is as follows. For example, in the NTSC signal of a TV, about 30 screens are sent and displayed per second. Therefore, the transfer time allowed for one screen is 30 milliseconds or less, and if the screen cannot be received regularly every 30 milliseconds, the application cannot display a moving image correctly. In order to measure a group of packets loaded with screen information sent at intervals of 30 milliseconds, time accuracy of at least 1 millisecond is required. In the future, in consideration of higher-speed network lines that will appear in the future, measurements at more detailed time intervals will be required.
[0014]
Furthermore, when developing an application, it is necessary to grasp the network bandwidth used by the developed application. Due to the widespread use of MPU, which has been markedly accelerated, there is a high possibility that the application developer will perform an unexpected burst-like packet transmission.
[0015]
Some packets included in the bursty packet group exceeding the network allowance cannot fit into the buffer of the node device constituting the network, resulting in packet loss. At this time, resending is performed as a function of the OS that is the operating environment of the application. However, when the burst occurs again, the same phenomenon is repeated, and the result of exceeding the restrictions necessary to ensure the real-time property of the application It becomes.
[0016]
In order to prevent these problems, it will be essential in the future to design applications with high network transparency by measuring packet groups at detailed time intervals on the application development side.
[0017]
The conventional measurement method is aimed at monitoring long-term behavior of network traffic, and performs measurement in units of one second or more. As described above, it is impossible to grasp the burst characteristics of the packet flow specific to the application.
[0018]
Here, a method of capturing all communication data using the all communication data capturing function of the conventional traffic monitoring apparatus and performing post-processing on all the communication data after capturing is also conceivable.
[0019]
FIG. 1 shows the configuration of a virtual device using a conventional traffic monitoring device for carrying out such a method.
[0020]
This device comprises a conventional traffic monitoring device 1, a processing unit 2 for performing high time resolution display, and a secondary storage device 3 for storing packets. In the conventional traffic monitoring apparatus 1, packets in a line are temporarily stored in the high-speed primary storage unit 13 via the line interface unit 11 and the writing unit 12, and then the packets are transmitted via the reading unit 14 and the secondary storage interface 15. To the secondary storage device 3. Thereafter, the processing unit 2 reads and analyzes the packets accumulated in the secondary storage device 3 as offline processing, and displays the traffic transition on the display unit 23.
[0021]
In such a configuration, the time that can be observed at one time depends on the capacity of the primary storage unit 13 of the conventional traffic monitoring device 1 to be used. For example, in the case of a line with a usage rate close to 1 Gbps, the time is less than several seconds. Absent. Further, since all stored packet information is transferred between a plurality of storage devices, continuous measurement in real time cannot be performed.
[0022]
Embodiments of the present invention will be described below.
[0023]
FIG. 2 is a diagram showing a schematic configuration of the communication quality measuring apparatus according to the embodiment of the present invention. This communication quality measuring apparatus includes a selective extraction mechanism 31 that extracts a specific packet flow from a number of packet flows that flow on the network, a packet length integration mechanism 32 that integrates the packet length values of the extracted packets, and a packet length integration. The integrated value of the packet length obtained by the mechanism is periodically read at predetermined time intervals, and the integrated value periodic readout mechanism 33 for displaying or storing the integrated value, the display mechanism 34, and the storage unit 35 are provided. is doing. The operation of this communication quality measuring apparatus is as follows.
[0024]
The packet selected by the selection / extraction mechanism 31 is duplicated and input to the packet length integration mechanism 32. The packet length accumulation mechanism 32 accumulates the packet length for each packet using a counter corresponding to the header of the input packet, and accumulates the accumulated value in a memory in the packet length accumulation mechanism. The processing so far is executed as needed according to the arrival of a packet. That is, the selection / extraction mechanism 31 and the packet length integration mechanism 32 sequentially perform processing in synchronization with arrival of a packet.
[0025]
The operation of the integrated value periodic readout mechanism 33 will be described with reference to FIG. After initialization (step S1), a time interrupt wait state is entered (step S2). Then, upon receiving a time interrupt every fixed time (1 ms), the integrated value stored in the memory in the packet length integrating mechanism is periodically read out, transferred to the main memory in the integrated value periodic reading mechanism, and Then, the memory value in the packet length integrating mechanism for accumulating the integrated value is initialized (set to 0) (step S2). Then, the integrated value periodic reading mechanism 33 sends the read integrated value from the main memory to the display mechanism 34 and stores it as a file in the storage unit 35 (step S4). In the display mechanism 34, for example, for a specific type of packet, the transition of traffic is displayed with the time as the horizontal axis and the integrated value as the vertical axis. Further, it is possible to perform processing for facilitating the burst characteristic evaluation on the integrated value and display the processed data.
[0026]
Further, instead of displaying the integrated value on the display mechanism 34 or storing it in the storage unit 35, as shown in FIG. 4, it may be transmitted to a remote monitoring device or the like via the network 40 and displayed there. .
[0027]
That is, the configuration shown in FIG. 4 has a network transmission mechanism 41 instead of the display mechanism 34 and the storage unit 35. A network receiving mechanism 42 and a display mechanism 43 are connected via the network 40.
[0028]
As shown in the flow of FIG. 5, in this configuration, the integrated value reading mechanism 33 transmits the read integrated value to the network 40 via the network transmission mechanism 41 (step S14). The receiving side continues to wait in the display data waiting state and displays the integrated value on the display mechanism 43 when the network receiving mechanism 42 receives the integrated value (step S15) (step S16). It is also possible to perform processing for facilitating the burst characteristic evaluation on the integrated value and transmit the processed data via the network.
[0029]
More specifically, the communication quality measuring apparatus according to the present embodiment has the functional configuration shown in FIG. The line interface 51, the header information extraction unit 52, and the packet information search unit 53 shown in FIG. 6 correspond to the selection / extraction mechanism 31 of FIG. 2, the integration mechanism 54 and the counter unit 56 correspond to the packet length integration mechanism 32, and the fixed time. The interval reading unit 55 corresponds to the integrated value reading mechanism 33. The operation of the configuration shown in FIG. 6 is as follows.
[0030]
The packet input via the line interface 51 is input to the header information extraction unit 52, where the header information is extracted. Then, the packet information search unit 53 uses the header information to search for a counter identifier of the counter unit 56 corresponding to the header information. When the retrieval of the identifier is successful, the header information extraction unit 52 passes the packet length and the identifier to the accumulation mechanism 54, and the accumulation mechanism 54 accumulates the packet length using a counter corresponding to the identifier. The processing so far is executed as needed according to the arrival of the packet.
[0031]
The information in the counter unit 56 is periodically read out by the fixed time interval reading unit 55, and the counter is reset at every reading. As described above, the reading interval is a time (minimum 1 msec) during which the behavior of the application can be observed. Then, the read counter value is displayed on the display unit 58 via the display / accumulation processing unit 57 and stored in the measurement result storage unit 59.
[0032]
Next, an example of a method for measuring communication quality using the communication quality measuring apparatus of the present invention will be described.
[0033]
FIG. 7 is a diagram showing a configuration example when measuring communication quality using the communication quality measuring apparatus 60 of the present invention. In this configuration, the communication quality measuring device 60 measures the packet flow f1 immediately after being sent from the data sending server 61 and the packet flow f2 immediately before the data receiving client 63 after passing through the network 62, and compares the measurement results. To do. By measuring and evaluating the difference in burst characteristics between the entrance and exit of the network, how the burst characteristics of the packet flow sent from the data sending server 61 are affected by the transfer in the network 62 Can be observed. The packet flow f1 immediately after the data transmission server 61 can be considered as a packet flow unique to an application on the assumption of an ideal network in which there is no packet flow that is not a measurement target.
[0034]
At this time, the application of the data transmission server 61 adds tag information necessary for identifying the burst transfer portion to each packet and outputs it to the network 62. It is also possible to output measurement packets to the network at a level that does not affect the application.
[0035]
The change of the burst characteristics can be observed by comparing the traffic transition display with time on the horizontal axis and integrated value on the vertical axis at the entrance and exit of the network.
[0036]
In addition, the burst characteristics described above are based on the integrated value of the packet length periodically read from the integrated value periodic reading mechanism, the throughput of the packet burst transfer portion (the average value of the communication amount per unit time), and the interval at which the burst transfer appears. It is also possible to obtain by calculating the time between bursts.
[0037]
FIG. 8 is a diagram illustrating a state before and after a certain packet flow passes through the network. The packet included in each burst transfer portion includes tag information for identification, and the burst transfer portion is identified based on this tag information. As another method for identifying the burst transfer portion, a threshold value related to the communication amount per unit time may be provided, and the burst transfer portion may be identified when the communication amount equal to or greater than the threshold value continues for a predetermined time.
[0038]
FIG. 9 shows an example of the evaluation method in the case of using the throughput of the burst transfer portion of the packet and the time between bursts, which is the interval at which the burst transfer appears. The throughput (average value of communication amount per unit time) for each burst transfer portion shown in FIG. 8 is plotted on a two-dimensional plane with the vertical axis and the time between bursts on the horizontal axis to obtain a characteristic diagram (evaluation plane). . By obtaining such an evaluation plane for the entrance and exit of the network, it is possible to measure the characteristics that the network gives to the application.
[0039]
When the network is evaluated by comparing the traffic characteristics before and after passing through the network as described above, the communication quality measuring apparatus can be configured as shown in FIG. That is, the reference data comparison mechanism 71 and the reference data storage unit 72 are provided in the configuration of FIG. The reference data accumulating unit 72 accumulates in advance, as reference data, burst characteristics of a packet flow unique to an application on the premise of a network in an ideal state where there is no packet flow not to be measured. This reference data can be obtained, for example, by measuring the packet flow f1 in the configuration of FIG.
[0040]
The reference data comparison mechanism 71 compares the burst characteristics of the packet flow obtained by the integrated value periodic reading mechanism 33 with the reference data stored in the reference data storage unit 72 and analyzes the difference. In this case, the display mechanism 34 can display the output of the integrated value periodic readout mechanism 33 and the output of the reference data comparison mechanism 71. The burst characteristic used for comparison may be a time transition of the traffic volume or may be obtained by a method as shown in FIG.
[0041]
Next, a detailed configuration of the communication quality measuring apparatus according to the present invention that is close to the hardware implementation will be described below with reference to FIG. Hereinafter, a configuration in the case of having a reference data comparison mechanism and a display mechanism will be described.
[0042]
As shown in FIG. 11, this communication quality measuring apparatus includes an input-side line interface 81, an output-side line interface 82, a duplicator 83, a selected packet length extractor 84, an integrated value storage memory 85, an integrated value storage memory address. A search table 86, an adder 87, an initialization value register 88, an arbitration circuit 89, an interface circuit 90, an MPU 91, a main memory 92, a secondary storage device 93, a real-time interrupt generation device 94, and a display device 95 are provided. The line interfaces 81 and 82, the duplicator 83, and the selected packet length extractor 84 correspond to, for example, the selection / extraction mechanism 31 shown in FIG. 10, and the integrated value storage memory 85, the integrated value storage memory address search table 86, and the adder 87, the initialization value register 88 and the arbitration circuit 89 correspond to the packet length integrating mechanism 32, the main memory 92 or the secondary storage device 93 corresponds to the reference data storage unit 72, and the MPU 91, the main memory 92, and the real time The interrupt generator 94 and the program stored in the main memory 92 correspond to the integrated value periodic reading mechanism 33 and the reference data comparison mechanism 71, and the display device 95 corresponds to the display mechanism 34. Next, the function of each unit shown in FIG. 11 will be described.
[0043]
The duplicator 83 duplicates the packet. The selected packet length extractor 84 extracts a specific packet from the copied packet and calculates the packet length. The integrated value accumulation memory 85 stores and stores the integrated value of the packet length at an address corresponding to the header information of the packet. The integrated value memory address search table 86 searches the header information of the packet for the address where the integrated value stored in the integrated value storage memory 85 is stored, and returns it to the selected packet length extractor 84.
[0044]
The adder 87 adds the packet length of the packet extracted by the selected packet length extractor 84 to the accumulated value so far accumulated in the accumulated value accumulation memory 85. The initialization value register 88 stores an initial value used when the integrated value accumulation memory 85 is initialized. The arbitration circuit 89 arbitrates access to the integrated value storage memory 85.
[0045]
In FIG. 11, 96 is a packet stream duplicated by the duplicator 83, 97 is the extracted packet length, 98 is the address of the accumulated value storage memory 85 obtained from the accumulated value memory address search table 86, and 99 is the MPU 91. This is a bus that connects the interface circuit 90, the MPU 91, the main memory 92, the secondary storage device 93, the real-time interrupt generation circuit 94, and the display device 95, which are essential for carrying out the processing.
[0046]
Next, the operation of this apparatus will be described together with the details of each of the above components.
The line interface 81 connects to a line (network), converts a packet transmitted as a physical signal through the line into a logically processable signal, and transfers the signal to the duplicator 83. The duplicator 83 duplicates the packet signal in a complete form, and outputs one to the line interface 82 and the other to the selected packet length extractor 84. The line interface 82 performs a process reverse to that of the line interface 81 and outputs the packet signal received from the duplicator 83 to the line.
[0047]
The packet (96) duplicated by the duplicator 83 is passed to the selected packet length extractor 84.
[0048]
The operation of the selected packet length extractor 84 will be described with reference to FIG.
[0049]
The selected packet length extractor 84 extracts the header information of the packet 96 when the packet arrives from the packet arrival waiting state (step S21) (step S22). Specifically, in order to identify a series of communications (packet flows) performed by an application, a destination IP address, a source IP address, a protocol type (TCP / UDP type), a TCP or UDP destination port number, and a source Extract the port number. This series of header information is called a flow ID.
[0050]
The selected packet length extractor 84 calculates the packet length and requests the accumulated value accumulation memory 15 address from the accumulated value accumulation memory address search table 86 using the extracted flow ID (step S23).
[0051]
The selected packet length extractor 84 outputs the packet length 97 and the address 98 of the integrated value storage memory 85 to the adder 87 when the above-described search is successful (other than address 0 returns) (YES in step S24). (Step S25). If the search fails (address 0 is returned) (NO in step S24), the corresponding packet is discarded (step S26), and the process returns to the operation of waiting for the packet (96) from the duplicator 83.
[0052]
FIG. 13 is a diagram showing an example of the integrated value storage memory address search table 86. In the figure, 101 is a flow ID field, 102 is an integrated value storage memory address field, 103 is an input of a flow ID, and 104 is an address in the integrated value storage memory 85.
[0053]
In the integrated value accumulation memory address search table 86, the flow ID field 101 is searched based on the flow ID 103 obtained by the selected packet length extractor 84. When the same flow ID as the flow ID 103 exists in the flow ID field 101, the address registered in the corresponding integrated value storage memory address field 102 is output as the address 104 of the integrated value storage memory 85. If it does not exist, a special address value (address 0) is output as the address 104 of the integrated value storage memory 85. The registered contents of the flow ID field 101 and the accumulated value storage memory address field 102 can be changed by the MPU 91 via the interface circuit 90 at any time.
[0054]
In FIG. 11, the adder 87 reads the data stored at the address from the integrated value storage memory 85 based on the address 98 of the integrated value storage memory 85 transferred from the selected packet length extractor 84.
[0055]
FIG. 14 shows an example of the integrated value accumulation memory 85, which has the same configuration as a general memory. In the figure, 201 is an address field, 202 is a data field (data here is an integrated value), 203 is an address input, and 204 is data input / output.
[0056]
The address is a value defined by continuous integers, and the data is arbitrary data. In the case of a read operation, the data stored in the field 202 corresponding to the address 201 corresponding to the input 203 is output as 204. In the case of a write operation, the data 204 is stored in the field 202 corresponding to the address 201 corresponding to the input 203.
[0057]
The adder 87 reads the data stored in the integrated value accumulation memory 85, adds the value of the packet length 97 described above to the data, and stores it again in the integrated value accumulation memory 85. At this time, the address used for reading and writing is given from the selected packet length extractor 84.
[0058]
The initialization value register 88 is a register that accumulates an initial value used when initializing the field 202 of the integrated value accumulation memory 85, and sets “0”. The initialization timing will be described later.
[0059]
The arbitration circuit 89 arbitrates access to the integrated value accumulation memory 85 of each of the adder 87 and the interface circuit 90. Further, when the integrated value accumulation memory 85 is initialized, the value accumulated in the initialization value register 88 is stored at a specified address.
[0060]
The processing so far is executed in response to arrival of a packet registered in the integrated value accumulation memory address search table 86. As a result, the packet length of the arrived packet is integrated with the value stored in the data field of the integrated value accumulation memory 85 as needed.
[0061]
The interface circuit 90 realizes access to the integrated value storage memory address search table 86 and the arbitration circuit 89, and stores the integrated value storage memory 85 and the integrated value from the program stored in the main memory 92 and processed by the MPU 91. Mediates access to the storage memory address search table 86.
[0062]
The subsequent processing will be described with reference to FIG. The process described below is a process executed in accordance with a program instruction stored in the main memory 22.
[0063]
At initialization, the program registers the header information of the packet to be measured in the integrated value storage memory address search table 86, and then sets all the data fields of the integrated value storage memory 85 as values of the initialization value register 88. In order to perform the processing and to read out the integrated value accumulation memory 85 at a constant time interval, the real time interrupt generator 94 is set to generate an interrupt to the MPU 91 at a constant time interval (step S31).
[0064]
The program waits until the real time interrupt generation device 94 generates an interrupt signal to the MPU 91 (step S32). When the real-time interrupt generator 94 generates an interrupt signal, the program shifts from a waiting state to an operation of reading the data field of the integrated value accumulation memory 85.
[0065]
At this time, the value of the data field 202 is read from the addresses (201, 104) corresponding to all the accumulated value accumulation memory address fields 102 registered in the accumulated value accumulation memory address search table 86, and is stored in a designated area in the main memory 92. Store (step S33). The read field is initialized by sequentially writing the value of the initialization value register 88 (step S34). Of the data stored in the main memory 92, the data defined as the display target by the program is transferred to the display device 95 for display (step S35).
[0066]
By repeating the processing so far, it becomes possible to periodically obtain the total packet length of the packet flow based on a specific application registered in the real-time interrupt generation device 94 within a certain time. By plotting the time axis on the horizontal axis and plotting the read value of the integrated value storage memory 85 on the vertical axis, it is possible to obtain the transition of the communication amount per unit time of the packet flow.
Further, the comparison processing described with reference to FIGS. 8 and 9 is performed at a time interval larger than the time interval for reading the integrated value accumulation memory 85 generated by the real-time interrupt generation device 84. That is, time determination is performed in step S36, and comparison processing is performed when the designated evaluation time has elapsed (step S37).
[0067]
In the comparison process, the throughput of the packet burst transfer part (the average value of the amount of communication per unit time) and the time between bursts are obtained, and the throughput for each burst transfer part is plotted on the vertical axis and the time between bursts on the horizontal axis. Plot on the plane, create a characteristic diagram (evaluation plane) after passing through the network as shown in FIG. 9, and show the burst characteristics of the same packet flow at the time of application ideal operation before passing through the network as shown in FIG. The data is stored in advance in the next storage device 23 as reference data, and the throughput for each burst transfer portion is plotted on a two-dimensional plane with the vertical axis representing the throughput and the time between bursts on the horizontal axis. Create an evaluation plane. These may be displayed on the display device 95 as they are, or the difference between them may be displayed. In this way, the quality of the network is measured.
[0068]
In addition, traffic transition reference data is prepared with time on the horizontal axis and integrated value on the vertical axis, and this is compared with traffic transition measurement results with time on the horizontal axis and integrated value on the vertical axis. May be.
[0069]
The comparison between the reference data and the measurement data in this case will be described in more detail.
[0070]
The reference data is, for example, a packet burst transfer pattern with a constant period, which is found in an application that delivers real-time moving images, sounds, and the like over a network. Taking an application that distributes a moving image based on an NTSC signal, which is a general TV signal, as an example, when transmission processing is performed in units of one screen, one screen is transmitted every about 33 milliseconds. Assuming that the data amount of one screen is 1 MByte, a burst of 1 MByte occurs about every 33 milliseconds. When the capacity of the network line is 1 Gbps and the computer executing the application has a transmission performance of 1 Gbps, a full-rate burst of the 1 Gbps line over 8 milliseconds occurs every 30 milliseconds. This repetition is reference data in the case of the application. Although the reference data varies depending on the application, the reference data has a specific repetition pattern when the capacity of the network line is constant.
[0071]
When a burst pattern with repeatability by the application is distributed via the network, the burst interval and burst continuous time are compared with the ideal state not via the network due to the lines constituting the network and the buffer status of the node equipment. Changes. This is measurement data.
[0072]
The meaning of comparing reference data and measurement data means creating a difference between two repeated patterns. For example, a graph showing the time change of the difference is created and displayed. If the difference is large, it indicates that the influence on the burst characteristics by the network is large, and if the difference is small, it indicates that the influence is small.
[0073]
In addition, as reference data, it is not an application-specific packet flow burst pattern (characteristic), assuming a network in an ideal state where there is no packet flow that is not subject to measurement, but a specific packet flow generated by a commercially available generator. A burst pattern may be used. At this time, by comparing the reference data generated by the generator with the actual measurement data, it is possible to indirectly measure the influence of the packet flow specific to the application in the network. In addition, it is also possible to configure such that post-analysis can be performed by copying and recording the measurement result in a nonvolatile storage means.
[0074]
Next, an example of traffic measurement using the communication quality measurement device according to the present invention will be described including the difference from the conventional device.
[0075]
Examples of measurement results of traffic transitions of packets transmitted by MPEG2 streaming systems (device A and device B) having different traffic characteristics are shown in FIGS. FIG. 16 shows the result measured by the conventional apparatus, and FIG. 17 shows the result measured by the communication quality measuring apparatus of the present invention.
[0076]
In FIG. 16, there is almost no difference in the traffic transition between the devices A and B. On the other hand, in FIG. 17, it can be seen that apparatus A generates traffic that stably transitions at a maximum of 10 Mbps, while apparatus B generates a burst exceeding 30 Mbps in a cycle of 20 milliseconds. That is, in the conventional apparatus, since the measurement time interval is long, bursts at short intervals cannot be observed like the traffic generated by the apparatus B. On the other hand, since the apparatus of the present invention can grasp traffic at short time intervals, it can observe bursts with a period of 20 milliseconds.
[0077]
FIG. 18 is a diagram illustrating an example in which the distribution adjustment of the streaming distribution application is performed using the communication quality measurement apparatus of the present invention. That is, before adjustment, the streaming distribution application has a traffic characteristic that repeats a burst exceeding 800 Mbps, as shown in “Transition of undeliverable traffic” in FIG. 18, and when this traffic is transmitted through the network, Packet loss was observed. Therefore, distribution adjustment was performed to send the traffic shown in “Distributable traffic transition” in FIG. 18. As a result, no packet loss occurred through the network, and the distribution was successful. Such adjustment is made possible by the communication quality apparatus of the present invention that can measure traffic at short time intervals.
[0078]
The present invention is not limited to the above-described embodiments, and various modifications and applications are possible within the scope of the claims.
[0079]
【The invention's effect】
As described above, according to the present invention, traffic measurement with high time resolution can be performed in real time. In addition, it is possible to measure in detail the impact of a series of packet flows originating from a specific application executed on a server and a client connected to the network in the network. It is possible to make a proper distribution adjustment.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a virtual device using a conventional traffic monitoring device.
FIG. 2 is a diagram showing a schematic configuration of a communication quality measuring apparatus according to an embodiment of the present invention.
3 is a diagram for explaining the operation of an integrated value periodic readout mechanism in the communication quality measuring apparatus shown in FIG. 2;
FIG. 4 is a diagram showing a schematic configuration of a communication quality measuring apparatus according to an embodiment of the present invention, and is a diagram showing a configuration when measurement data is transmitted to a network.
5 is a diagram for explaining the operation of an integrated value periodic readout mechanism in the communication quality measuring apparatus shown in FIG. 4;
FIG. 6 is a diagram showing a functional configuration of a communication quality measuring apparatus according to an embodiment of the present invention.
FIG. 7 is a diagram for explaining a method of measuring the effect of transfer in a network on burst characteristics of an application-specific packet flow.
FIG. 8 is a diagram showing a state of a packet flow before and after passing through a network.
FIG. 9 is a diagram for explaining an example of an evaluation method.
FIG. 10 is a diagram showing a schematic configuration of a communication quality measuring apparatus according to an embodiment of the present invention, and is a diagram showing a configuration when a reference data comparison mechanism is provided.
FIG. 11 is a diagram showing a detailed configuration of a communication quality measuring apparatus according to an embodiment of the present invention.
12 is a diagram for explaining the operation of a selected packet length extractor 84. FIG.
FIG. 13 is a diagram illustrating an example of an integrated value storage memory address search table.
FIG. 14 is a diagram illustrating an example of an integrated value accumulation memory.
FIG. 15 is a diagram showing a flow of processing corresponding to a program stored in a main memory.
FIG. 16 is a diagram showing an example of traffic transition measured by a conventional apparatus.
FIG. 17 is a diagram showing an example of traffic transition measured by the apparatus of the present invention.
FIG. 18 is a diagram illustrating an example in which distribution adjustment of a streaming distribution application is performed using the communication quality measurement apparatus of the present invention.
[Explanation of symbols]
1 Conventional traffic monitoring device
2 Processing unit for high time resolution display
3 Secondary storage device
11 Line interface section
12 Writing part
13 High-speed primary storage
14 Reading section
15, 21 Secondary storage interface
22 Traffic transition display processing section
23 Display
31 Selective extraction mechanism
32 Packet length integration mechanism
33 Integrated value periodic readout mechanism
34, 43 Display mechanism
35 Accumulator
41 Network transmission mechanism
42 Network reception mechanism
51 Line interface
52 Header information extractor
53 Packet information search unit
54 Integration mechanism
55 Fixed time interval readout
56 Counter section
57 Display / accumulation processor
58 display
59 Measurement result storage
60 Communication quality measuring device
61 Data transmission server
63 Data receiving client,
71 Reference data comparison mechanism
72 Reference data storage mechanism
81 Line interface on input side
82 Line interface on output side
83 Replicator
84 Select packet length extractor
85 Integrated value storage memory
86 Integrated value storage memory address search table
87 Adder
88 Initialization value register
89 Arbitration circuit
90 Interface circuit
91 MPU
92 Main memory
93 Secondary storage
94 Real-time interrupt generator
95 Display device

Claims (16)

A measurement device for measuring the amount of traffic of packet data flowing on a network,
An accumulating unit that accumulates packet lengths of packets having predetermined header information with respect to sequentially input packets;
An accumulator for accumulating the integrated value;
An integrated value reading unit that reads and outputs the integrated value from the storage unit at a predetermined time interval;
The measuring device has a real-time interrupt unit that generates an interrupt signal at the time interval, and when the real-time interrupt unit generates an interrupt signal, reads the integrated value from the storage unit, from the integrated value , The communication amount per unit time is obtained, and when the communication amount that is equal to or greater than a predetermined threshold value continues for a predetermined time or more, it is determined that the communication portion at that time is the burst transfer portion of the packet, and the burst transfer portion Calculate the burst characteristics of the packet flow by calculating the average value of traffic per unit time and the time between bursts, which is the interval at which burst transfer appears,
The storage unit initializes the accumulated value every time the integrated value is read.   The measuring apparatus according to claim 1, wherein the time interval is 1 second or less. The integrating unit is
The header information of the input packet is extracted, the address of the storage unit corresponding to the header information is acquired from a table in which the header information and the address are recorded in association with each other, and the integrated value is stored in the acquired address The measuring device according to claim 1 or 2. The integrating unit includes a selected packet length extractor, an integrated value memory address search table in which packet header information and an address of a storage unit are recorded in association with each other, and an adder,
The selected packet length extractor extracts header information of an input packet, calculates the packet length, searches the integrated value memory address search table using the extracted header information, and calculates the integrated value memory address Learn the address corresponding to the header information from the search table,
The adder acquires an integrated value stored at an address corresponding to the header information in the storage unit, adds the packet length to the integrated value, and adds the integrated value after delivery to the address in the storage unit The measuring device according to claim 1 or 2.   The measurement apparatus according to claim 1, further comprising a display unit that displays the integrated value or a value obtained by processing the integrated value.   The measurement apparatus according to claim 1, further comprising a transmission unit that transmits the integrated value or a value obtained by processing the integrated value to another apparatus via a network. The measuring device is
A reference data accumulating unit for accumulating reference data to be compared with the measurement result by the measuring device in advance;
The measurement apparatus according to claim 1, further comprising a reference data comparison unit that compares the measurement result with reference data.   The measurement apparatus according to claim 7, wherein the reference data comparison unit obtains a difference between the measurement result and the reference data. A measurement method in a measurement device for measuring the amount of traffic of packet data flowing on a network,
An integration step of integrating the packet length of the packet having predetermined header information with respect to the sequentially input packets and storing the integrated value in the storage unit;
A step of reading and outputting the integrated value from the storage unit at a time interval specified in advance,
The measuring device has a real-time interrupt unit that generates an interrupt signal at the time interval, and when the real-time interrupt unit generates an interrupt signal, reads the integrated value from the storage unit, from the integrated value , The communication amount per unit time is obtained, and when the communication amount that is equal to or greater than a predetermined threshold value continues for a predetermined time or more, it is determined that the communication portion at that time is the burst transfer portion of the packet, and the burst transfer portion A step of calculating a burst characteristic of a packet flow by calculating an average value of communication amount per unit time and an interburst time which is an interval at which burst transfer appears,
The accumulating unit initializes the accumulated value every time the integrated value is read out. The measurement method according to claim 9 , wherein the time interval is 1 second or less. In the step of accumulating the integrated value in the accumulating unit,
The header information of the input packet is extracted, the address of the storage unit corresponding to the header information is acquired from a table in which the header information and the address are recorded in association with each other, and the integrated value is stored in the acquired address The measuring method according to claim 9 or 10 . The measuring device has an integration unit that executes the integration step,
The integrating unit includes a selected packet length extractor, an integrated value memory address search table in which packet header information and an address of a storage unit are recorded in association with each other, and an adder,
The selected packet length extractor extracts header information of an input packet, calculates the packet length, searches the integrated value memory address search table using the extracted header information, and calculates the integrated value memory address Learn the address corresponding to the header information from the search table,
The adder acquires an integrated value stored at an address corresponding to the header information in the storage unit, adds the packet length to the integrated value, and adds the integrated value after delivery to the address in the storage unit The measuring method according to claim 9 or 10 . Measurement method as claimed in any one of claims 8 to 12 further comprising the step of displaying the processed value the accumulated value or the integrated value. Measurement method according to any one of the integrated value or accumulated to further 9 claims comprising sending to another apparatus via the network the processed value value 14. The measurement result by the measuring apparatus, measuring method according to any one of claims 9 to 14 further comprising the step of comparing the reference data to be compared with the measurement results. The measurement method according to claim 15 , wherein, in the comparing step, a difference between the measurement result and the reference data is obtained.

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