JP2010074371A - Traffic generating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To restrain increase of memory usage in improving setting accuracy of a transmission load factor. <P>SOLUTION: This traffic generating device includes: a transmission stream image storage part 5-4 for storing a plurality of frame images corresponding to a plurality of types of streams; a stream transmission table 5-5 for storing information for designating a frame image in the transmission stream image storage part 5-4 in accordance with a transmission sequence; a stream information conversion part 5-3 for determining the number of appearance of the respective frame images in accordance with a transmission rate of each stream, and storing information for designating each frame image in the stream transmission table 5-5 to correspond to the number of appearance; a frame selection part 5-6 for sequentially reading the frame images from the transmission stream image storage part 5-4 based on the information for designating the frame images; and transmission means 5-7, 5-8 to output the frame images read by the frame selection part 5-6 to the outside. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a traffic generator used for a network load test or the like.

  In a network such as a LAN (local area network) and the Internet, for example, when a large-scale system is constructed or updated, a load test is performed in which packet data is actually transmitted over the network to check the status of each device. ing. In such a load test, a traffic generator is used to generate traffic for communication data transmitted over a network for testing (see, for example, Patent Documents 1 to 4).

  Below, an example of the traffic generator considered by the applicant of the present application will be given, and the technical contents as the background of the present invention will be described. FIG. 1 is a block diagram illustrating a configuration example of a traffic generation device. 1 includes a stream information storage unit (1-2), a stream information conversion unit (1-3), a transmission frame image storage unit (1-4), a frame selection unit (1-5), It consists of a frame transmission unit (1-6) and a transmission control unit (1-7). The stream information storage unit (l-2) stores the stream information defining the frame information (information indicating the frame structure) of each stream and the transmission rate information for a plurality of streams set by the user (1-1). To do.

  In the present application, when a plurality of frames having the same structure are transmitted, the series of frames is referred to as a stream. In addition, a data piece composed of a header (and trailer) and data to be transmitted is generally called a packet or a frame depending on a communication protocol layer, but in the present application, it is called a frame. Shall. The stream information conversion unit (1-3) expands the information stored in the stream information storage unit (1-2) into a transmission frame image and stores the information in the transmission frame image storage unit (1-4). The transmission frame image storage unit (1-4) stores a pattern (image) of a frame to be transmitted.

  FIG. 2 is a diagram for explaining an example of the stream information stored in the stream information storage unit (1-2) and the frame image stored in the transmission frame image storage unit (1-4). In this case, the stream information storage unit (1-2) stores J streams of stream 1, stream 2,. The contents of each stream 1 to J are frame information and transmission rate. The frame information is information representing the structure of a series of frames constituting each stream, and includes header information indicating the destination and transmission source of each frame constituting the stream, data contents or HTTP (HyperText Transfer Protocol), It is defined differently depending on the communication protocol such as SMTP (Simple Mail Transfer Protocol) or the type of service. The transmission rate is information representing the communication speed, and is defined by a relative band allocation ratio value in each of the streams 1 to J in this example. For example, assuming that 100 Mbps is the maximum communication speed and R1 = 10% is set for stream 1 and R2 = 20% is set for stream 2, communication speeds of 10 Mbps and 20 Mbps are set respectively. .

  On the other hand, in this case, the transmission frame image storage unit (1-4) is configured to have M storage areas having a fixed length of L bytes, and each storage area includes M of frames 1 to M. Frame images are stored. Each of the frames 1 to M is based on the frame information stored in the stream information storage unit (1-2) and the content of the transmission rate, for example, a desired communication protocol (for example, Ethernet (registered trademark) in the network interface layer or the data link layer). ), A frame image generated according to PPP (Point-to-Point Protocol, etc.), that is, data having the same format as the frame format actually transmitted.

  The contents of the frames 1 to M stored in the transmission frame image storage unit (1-4) are called in the order of frame 1, frame 2,. Become. In order to set the transmission rate with such a configuration, it is necessary to cause many frame images corresponding to streams having a large transmission rate to appear and to cause few frame images corresponding to streams having a low transmission rate to appear at the time of expansion. That is, at the time of expansion by the stream information conversion unit (1-3), the number of appearances of frames corresponding to each stream according to the frame information and transmission rate of each stream stored in the stream information storage unit (1-2) Will be determined. For example, if the transmission rate R1 of stream 1 stored in the stream information storage unit (1-2) is 10%, the transmission rate R2 of stream 2 is 20%, and the frame lengths of stream 1 and stream 2 are the same, The “stream a frame content” that is the content of frame 1 shown in FIG. 2 corresponds to stream 1, and “stream b frame content” that is the content of frame 2 and “stream c frame content” that is the content of frame 3. The frame image is expanded so that the ratio of the number of appearances of the stream 1 and the stream 2 becomes a value of 1: 2 so that the above corresponds to the stream 2.

  In addition, the number M (or depth M) of storage areas of the transmission frame image storage unit (1-4) indicates the number of streams and the frame length stored in the stream information storage unit (1-2) and the transmission. It is a value determined by the set value of the rate. If there are two types of streams, namely stream 1 and stream 2 (ie, J = 2), and if the frame length of each stream is the same, if both frame transmission rates are 50%, M must be at least two. Become. On the other hand, if it is 25% and 75%, for example, it is expanded into one frame and three frames, and in this case, four M are required. If 2% and 98%, for example, one frame and 49 frames are developed, so that at least 50 M is required.

  On the other hand, in FIG. 1, the frame selection unit (1-5) selects which frame in the transmission frame image storage unit (1-4) is to be transmitted by the frame transmission unit (1-6). The frame transmission unit (1-6) actually transmits the frame selected by the frame selection unit (1-5) toward a network such as a LAN. The transmission control unit (1-7) performs operation control (start / stop) of the frame transmission unit (1-6).

  In the above configuration, when a plurality of streams are transmitted with the transmission load factor set for each of the streams, it is necessary to perform the following processing shown in the flow in FIG. 3 from the setting to the transmission. In step (3-1), the user (1-1) sets the frame structure of each stream and the transmission load factor (transmission rate) of the stream in the stream information storage unit (1-2). In step (3-2), the stream information conversion unit (1-3) creates a pattern (image) of the frame to be actually transmitted from the stream information storage unit (1-2), and stores the transmission frame image in the memory. Part (1-4). At this time, expansion is performed with the number of appearances such that the following expression (1) holds between each stream, that is, between any two streams p and q of streams 1 to J.

  The frame length Lp or Lq in the above equation actually includes a minimum IFG value (Inter Frame Gap) (for example, 12 bytes), a preample (for example, 8 bytes) indicating a gap between frames.

Next, in step (3-3), the transmission control unit (1-7) starts transmission based on the frame image in the transmission frame image storage unit (1-4) created in step (3-2). Instruct. The operation of the frame selection unit (1-5) at the time of transmission is as follows, as shown in the flow in FIG. In step (4-1), the transmission frame image pointed to by the frame pointer is acquired from the transmission frame image storage unit (1-4). In step (4-2), the frame transmission unit (1-6) is instructed to transmit the acquired frame image. In step (4-3), the frame pointer is advanced by one. However, if the pointer points to the last frame, it points to the first frame.
JP 2006-295516 A JP 2002-217978 A JP-A-11-136288 JP-A-6-132799

  In Equation (1), when the transmission rate ratio Rp / Rq is very large (that is, the transmission rate of stream p is much larger than the transmission rate of stream q), the number of appearances Ap is much greater than Aq. Need to be bigger. Further, since the appearance numbers Ap and Aq are integers, the value of Ap + Aq tends to increase in such a case. That is, the depth M of the transmission frame image storage unit (1-4) is also increased.

  Further, in order to increase the setting accuracy of the transmission rate value, that is, the transmission load factor, it is necessary to increase the number of stages M of the transmission frame image storage unit (1-4), but the amount of memory used is represented by M × Lbyte. Therefore, increasing M increases the amount of memory used in proportion to L. The value of L varies depending on the structure of the frame. For example, Ethernet (registered trademark) may be 1500 bytes or more, and the transmission rate may be required to have an accuracy of 1% or less. At least 100, or more than tens of thousands if necessary.

  The present invention has been made in view of the above circumstances, and a traffic generation device capable of suppressing an increase in memory usage when increasing the transmission rate ratio between multiple streams and the setting accuracy of a transmission load factor. The purpose is to provide.

  In order to achieve the above object, in the present invention, as a first solution means, a stream image storage means for storing a plurality of frame images corresponding to a plurality of types of streams, and a frame image in the stream image storage means are designated. Stream transmission table that stores information to be transmitted according to the transmission order, and the number of appearances of each frame image is determined according to at least the transmission rate of each stream, and information that designates each frame image to correspond to the number of appearances is stream transmitted A control means for storing in the table, a frame selection section for sequentially reading the frame images from the stream image storage means based on information for designating the frame images stored in the stream transmission table, and a frame image sequentially read by the frame selection section. Output to outside Comprising a transmission unit that employs the means of.

  As a second solving means, the first means comprises a plurality of stream transmission tables and a selection means for selecting one of the stream transmission tables, and the frame selection unit is based on the stream transmission table selected by the selection means. Then, means for sequentially reading frame images from the stream image storage means is employed.

  As a third solving means, in the first or second means, the control means distributes and stores information designating a frame image in a stream transmission table, and the frame selection unit is based on the stream transmission table. Thus, a method is adopted in which the frame images of each type of stream are read out multiple times.

According to the present invention, the frame information to be transmitted and the transmission order are held as separate stream transmission tables as a data format for generating a stream. As a result, it is possible to suppress an increase in memory usage when increasing the transmission rate ratio between multiple streams and the setting accuracy of the transmission load factor.
Also, the stream transmission rate can be dynamically switched by switching the stream transmission table indicating a plurality of transmission orders.
Further, by distributing the appearance timings of a plurality of types of frame images, a more uniform transmission load factor can be realized.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 5 is a block diagram showing a functional configuration of the traffic generator 5 according to the present embodiment. The traffic generator 5 is a traffic generator that stores a plurality of frame images in advance corresponding to a plurality of types of streams, and generates traffic to be transmitted by calling the stored frame images in a predetermined order. A control unit as hardware, a storage device such as a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, and various peripheral devices for transmitting / receiving input, display and communication data, It is a device that operates by executing a program stored in a ROM or the like.

  When the internal configuration of the traffic generator 5 is shown for each function, the stream information storage unit (1-2), the stream information conversion unit (1-3), the frame transmission unit (1- 6) and a stream information storage unit (5-2), a stream information conversion unit (5-3), a frame transmission unit (5-7), and a transmission control unit (5- In addition to 8), a transmission stream image storage unit (5-4), a stream transmission table (5-5), and a frame selection unit (5-6) are provided. Of these components, the frame transmission unit (5-7) and transmission control unit (5-8) constitute transmission means.

  Similarly to the stream information storage unit (1-2) described with reference to FIG. 1 and FIG. 2, the stream information storage unit (5-2) is configured for a plurality of streams set by the user (5-1). The stream information defining the frame information (information indicating the frame structure) of each stream and the transmission rate information is stored. The stream information conversion unit (5-3) determines the number of appearances of each frame image in accordance with at least the transmission rate of each stream, and stores information for designating each frame image so as to correspond to the number of appearances of the stream transmission table (5-5) functions as a control means for storing, from the data of the stream information storage unit (5-2), the transmission stream image storage unit (5-4) and the stream transmission table (5-5) Create stored information.

  The transmission stream image storage unit (5-4) constitutes stream image storage means for storing a plurality of frame images corresponding to a plurality of types of streams, and stores a frame pattern (image) of each stream. . The stream transmission table (5-5) stores information specifying frame images in the transmission stream image storage unit (5-4) according to the transmission order. Information indicating the stream number corresponding to the storage area is stored in the order of transmission.

  The frame selection unit (5-6) acquires a frame image to be transmitted from the storage information of the stream transmission table (5-5) and the transmission stream image storage unit (5-4), and sends it to the frame transmission unit (5-7). Indicates the frame to be transmitted. The frame transmission unit (5-7) actually transmits the frame. The transmission control unit (5-8) performs operation control (start / stop) of the frame transmission unit (5-7).

  Here, with reference to FIG. 6, an example of the stored contents of the transmission stream image storage unit (5-4) and the stream transmission table (5-5) will be described. In this case, it is assumed that the stream information storage unit (5-2) stores J streams of stream 1, stream 2,. The contents of each stream 1 to J are frame information and a transmission rate, as in the stream information storage unit (1-2) described with reference to FIG. The frame information is defined differently depending on the header information indicating the destination and transmission source of each frame constituting the stream, the data content, the communication protocol such as HTTP and SMTP, or the type of service. The transmission rate is information representing the communication speed, and is defined by a relative band allocation ratio value in each of the streams 1 to J in this example.

  In the example shown in FIG. 6, the transmission stream image storage unit (5-4) is configured to have J storage areas having a fixed length of L bytes in this case. The contents of J frames corresponding to the stream J on a one-to-one basis are stored. The frame contents of each of the frames 1 to J are based on the contents of the frame information stored in the stream information storage unit (5-2), for example, a desired communication protocol (for example, Ethernet (registered trademark) in the network interface layer or the data link layer). ), A frame image generated according to PPP (Point-to-Point Protocol, etc.), that is, data in the same format as the frame format actually transmitted.

  On the other hand, the stream transmission table (5-5) only needs to have a bit length sufficient to indicate the stream number corresponding to any of the number J of streams, and thus the fixed length represented by the following equation (2). M storage areas are provided. Each storage area of the stream transmission table (5-5) has a stream number indicating one of the J frame contents (such as the address of the storage area of each stream) of the transmission stream image storage unit (5-4). 6, stream a to stream y) are stored. Here, ceiling (x) is a ceiling function and represents “the smallest integer greater than or equal to x with respect to the real number x”.

  The contents of each stream number (stream a to stream y) in the stream transmission table (5-5) are determined according to the frame information and transmission rate of each stream stored in the stream information storage unit (5-2). The Stream a to stream y in the stream transmission table (5-5) are called by the frame selection unit (5-6) in the order of stream a, stream b,. Each stream image (stream frame content) in the storage unit (5-4) is sequentially selected. In order to set the transmission rate with such a configuration, at the time of expansion from the stream information storage unit (5-2), a large number of stream numbers corresponding to streams with a large transmission rate appear, and a stream with a small transmission rate is supported. It is necessary to make fewer stream numbers appear.

  For example, if the transmission rate R1 of stream 1 stored in the stream information storage unit (5-2) is 10%, the transmission rate R2 of stream 2 is 20%, and the frame lengths of stream 1 and stream 2 are the same, The contents of stream a shown in FIG. 6 correspond to “stream 1 frame contents”, and the contents of stream b and stream c have the same value corresponding to “stream 2 frame contents”. The stream numbers (contents of streams a, b,...) Are expanded so that the ratio of the number of appearances of 2 becomes a value of 1: 2.

  Also, the number M (or depth M) of storage areas in the stream transmission table (5-5) is the number of streams stored in the stream information storage unit (5-2), the frame length, and the transmission rate. It is a value determined by the set value. If there are two types of streams, ie, stream 1 and stream 2 (ie, J = 2), and if the frame length of each stream is the same, if both frame transmission rates are 50%, M must be at least two. Become. On the other hand, if it is 25% and 75%, for example, it is expanded into one frame and three frames, and in this case, four M are required. If 2% and 98%, for example, one frame and 49 frames are developed, so that at least 50 M is required.

  In the traffic generator 5 shown in FIG. 5, it is necessary to perform the following processing shown in FIG. 7 from setting to transmission. In step (7-1), the user (5-1) sets the frame structure of each stream and the transmission load factor (rate) of the stream in the stream information storage unit (5-2). In step (7-2), the stream information conversion unit (5-3) stores the image of the frame to be transmitted in each stream from the stream information storage unit (5-2). -4) and the contents stored in the stream transmission table (5-5) describing the transmission order of frames belonging to each stream. At this time, the stream transmission table (5-5) is developed with the number of frames appearing so that the following equation (3) is established between the streams, that is, between any two streams p and q of the streams 1 to J. The frame length Lp or Lq in the following equation actually includes a minimum IFG value (Inter Frame Gap) (for example, 12 bytes), a preample (for example, 8 bytes) indicating a gap between frames.

  Next, in step (7-3), based on the information in the transmission stream image storage unit (5-4) and stream transmission table (5-5) created in step (7-2), the transmission control unit ( 5-8) instructs the start of transmission.

The operation of the frame selection unit (5-6) during transmission is as follows shown in FIG.
In step (8-1), the stream number of the transmission stream pointed to by the pointer is acquired from the stream transmission table (5-5). In step (8-2), the frame image of the stream number acquired in step (8-1) is acquired from the transmission stream image storage unit (5-4). In step (8-3), the frame transmission unit (5-7) is instructed to transmit the stream image acquired in step (8-2). In step (8-4), the pointer is advanced by one. However, when the pointer points to the end of the stream transmission table (5-5), it points to the beginning of the stream transmission table (5-5).

  As described above, according to the present embodiment, when the accuracy of the transmission load factor is to be increased, the number M of stages in the stream transmission table (5-5) is the same as the method described with reference to FIG. However, since the size of each storage area that varies depending on the number of stages M can be reduced, the number of stages of the transmission frame image storage unit (1-4) is increased by the method described with reference to FIG. As a result, an increase in the amount of used memory can be suppressed.

  That is, when the number of stages M of the stream transmission table (5-2) is increased, the amount of memory used increases in proportion to the above equation (3), which can generally be made smaller than the frame length L. Thus, the amount of increase in memory can be suppressed as compared with the case where it increases in proportion to the frame length L.

  Further, in the traffic generator 5 shown in FIG. 5, when the stream information conversion unit (5-3) stores information indicating the stream number in the stream transmission table (5-5), the frame information corresponding to each stream is stored. The storage order may be adjusted so that the appearance timing is distributed among a plurality of streams. That is, the information specifying the frame image can be distributed and stored in the stream transmission table (5-5). For example, when two types of streams are transmitted at a transmission rate of 2% and 98%, a frame corresponding to 2% is transmitted continuously, and then a frame corresponding to 98% is transmitted continuously. The frame transmission for 1% and the frame transmission for 49% can be performed in two steps. In this way, diverse traffic can be generated.

Next, a modification of the above embodiment will be described with reference to FIG.
In addition to the configuration of FIG. 5, the embodiment 5a shown in FIG. 9 has a plurality of stream transmission tables (5-5) and a table selection unit (9-1) for selecting one of these tables. ing. In FIG. 9, the same reference numerals are used for the same components as those in FIG.

  In the traffic generator 5a shown in FIG. 9, the stream transmission table (5-5) referred to by the table selection unit (9-1) can be switched even when the frame transmission unit (5-7) is transmitting. Therefore, even during frame transmission, the transmission load rate and transmission order of each stream can be changed dynamically.

  In each embodiment of the present invention, the frame information to be transmitted and the transmission order are held as separate tables as the data format of stream generation. As a result, it is possible to suppress an increase in memory usage when increasing the transmission rate ratio between multiple streams and the setting accuracy of the transmission load factor. In addition, the stream transmission rate can be dynamically switched by switching a plurality of transmission order tables.

  In addition, this invention is not limited to the said embodiment, For example, the following modifications can also be considered. In other words, it is possible to configure a network load test apparatus by providing a function for transmitting generated traffic and receiving it, and to change the blocks shown in FIG. 5 and FIG. It is possible as appropriate. Further, when the present embodiment is constituted by a computer (CPU) and a program executed by the computer, the program may be distributed via a computer-readable recording medium or a communication line.

It is a block diagram which shows the example of 1 structure of the traffic generator for demonstrating the background art of this invention. FIG. 4 is an explanatory diagram for explaining storage contents of a stream information storage unit (1-2) and a transmission frame image storage unit (1-4) in FIG. 1; It is a flowchart for demonstrating operation | movement of the structure of FIG. 6 is a flowchart for explaining another operation of the configuration of FIG. 1. It is a block diagram which shows embodiment of the traffic generator of this invention. FIG. 6 is an explanatory diagram for explaining storage contents of a stream information storage unit (5-2), a transmission stream image storage unit (5-4), and a stream transmission table (5-5) in FIG. 5; 6 is a flowchart for explaining the operation of the configuration of FIG. 5. 6 is a flowchart for explaining another operation of the configuration of FIG. 5. It is a block diagram which shows the modification of embodiment of the traffic generator of FIG.

Explanation of symbols

  5, 5a ... traffic generator, 5-2 ... stream information storage unit (stream image storage means), 5-3 ... stream information conversion unit (control means), 5-4 ... transmission stream image storage unit, 5-5 ... Stream transmission table, 5-6 ... frame selection unit, 5-7 ... frame transmission unit, 5-8 ... transmission control unit, 9-1 ... table selection unit (selection means)

Claims (3)

Stream image storage means for storing a plurality of frame images corresponding to a plurality of types of streams;
A stream transmission table for storing information designating a frame image in the stream image storage means according to a transmission order;
Control means for determining the number of appearances of each frame image according to at least the transmission rate of each stream, and storing information specifying each frame image in the stream transmission table so as to correspond to the number of appearances;
A frame selection unit that sequentially reads frame images from the stream image storage unit based on information designating frame images stored in the stream transmission table;
And a transmission means for outputting the frame images sequentially read out by the frame selection unit to the outside. Comprising a plurality of the stream transmission tables and a selection means for selecting one of the stream transmission tables;
2. The traffic generating apparatus according to claim 1, wherein the frame selection unit sequentially reads frame images from the stream image storage unit based on the stream transmission table selected by the selection unit. The control means distributes and stores information specifying a frame image in a stream transmission table, and the frame selection unit reads out the frame image of each type of stream in multiple times based on the stream transmission table. The traffic generator according to claim 1 or 2, characterized in that:

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