JP2000183883A - Device and method for multimedia traffic load generation and program recording medium therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a device which can easily generate traffic in consideration of various features of multimedia as a device which generates a traffic load on a network handling multimedia. SOLUTION: In a traffic data storage part 2, encoded traffic data of various multimedia are prepared. A transmission procedure and quality setting part 11 sets a transmission procedure and quality (IP address, transmission start time, etc.), for the generation of traffic according to a script and a traffic data storage part 2 and a traffic generation part 13 adds a header corresponding to a protocol to traffic data read in from the traffic data storage part 2 according to the information set by the part 11 to generate and send out a packet to the network.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a multimedia traffic load generating apparatus for generating a traffic load of a network handling multimedia.

[0002] With the spread of multimedia in the future, it is expected that various traffics will flow through networks. On the other hand, as the bandwidth of a network increases, it is necessary to check and test the capabilities of network equipment, and it is necessary to measure the load of various networks.

Generally, multimedia traffic has a characteristic that it is generated based on characteristics and standards of each medium. Therefore, it is desired to generate data traffic reflecting various media in order to create a network load state for testing and developing multimedia applications.

[0004]

2. Description of the Related Art Conventionally, there is a network analyzer for monitoring data flowing on a network, and there is a function of applying a load to the network as a part of the function. However, the network analyzer is basically limited to the function of monitoring data flowing on the network, and the traffic generation function of the network analyzer sends out some functions of the network protocol of several bytes scale,
It is just a test to see if the data is correctly generated and connected. Therefore, it was not possible to generate data traffic in consideration of the characteristics of multimedia having various patterns, and it was not possible to put a load on the network from the standpoint of traffic generation with a designated band.

[0005]

A conventional network traffic generation device such as a traffic generation function of a network analyzer has no method for specifying a packet transmission interval and a packet length, and transmits a packet by specifying byte contents. As a result, traffic cannot be generated for the purpose of reproducing a specific medium.

[0006] When handling multimedia traffic, it is important to handle not only packets as described above but also to transmit traffic of a pattern conforming to various multimedia standards. It is also an issue to realize a function of simulating degradation such as packet loss that can occur in a network when transmitting traffic.

[0007] The present invention solves the above-mentioned problems, generates multimedia traffic based on various standards by a simple mechanism, and generates network traffic capable of simulating degradation that can occur in a network. The purpose is to enable.

[0008]

In order to solve the above-mentioned problems, the apparatus for generating multimedia traffic according to the present invention has various traffic patterns in a standard data template, and switches between them according to the traffic to be transmitted. Thus, multimedia traffic is realized. The standard data template is traffic data that has been encoded (encoded), and does not require a real-time encoding device at the time of transmission.
Also, in order to easily perform a traffic load test, the order in which traffic is transmitted can be described by a script.

FIG. 1 is a diagram showing an example of a block configuration according to the present invention. The traffic load generation device 1 inputs a script for generating traffic from the script input device 3, a transmission procedure / quality setting unit 11 for setting a packet transmission procedure and traffic quality, and a network such as Ethernet (registered trademark). In the information set by the transmission procedure / quality setting unit 11 to transmit a packet to the
To transmit a packet by attaching a header to traffic data based on setting information from a MAC address resolution unit 12 for acquiring a MAC address from an address and a transmission procedure / quality setting unit 11, or to generate a packet loss in a pseudo manner. Generation unit 13 for discarding packets
And a transmission log generation unit 14 for recording transmission information on the transmission history.

The traffic data storage unit 2 is a magnetic disk or other secondary storage device that stores various multimedia traffic data such as text data, image data, and audio data that have been encoded in advance. The script input device 3 is a device for inputting a script defining a transmission procedure and traffic quality.
Keyboard device, GUI (Graphical User Interface)
It is composed of a device having Alternatively, the script input device 3 may be a device such as a magnetic disk that stores a script created in advance. As the traffic quality, transmission parameters such as the type of media and the band used can be specified.

The present invention operates as follows. The traffic load generation device 1 interprets the script input from the script input device 3 and sets a transmission procedure. After that, the traffic data stored in the traffic data storage unit 2 is copied and read out on the memory,
The transmission procedure / quality setting unit 11
The MAC address is obtained from the IP address set in the step. The traffic generation unit 13 generates a traffic load by attaching a header to the traffic data to form an IP packet based on the setting information by the transmission procedure / quality setting unit 11 and transmitting or discarding the packet data. The transmission information at this time is left in the memory. The transmission log generator 14 creates and records a transmission log from transmission information left in the memory during transmission.

In the present invention, since a multimedia traffic pattern is prepared in advance, network traffic can be generated by converting these data into IP packets based on time information. That is,
By specifying multimedia data stored in a format conforming to a standard template and transmission parameters such as a band, multimedia traffic as a network load can be easily obtained.

[0013]

Embodiments of the present invention will be described below. First, traffic data used in the present invention will be described. This apparatus stores templates of various multimedia traffic patterns as traffic data in a traffic data storage unit 2 constituted by a secondary storage device such as a magnetic disk. Multimedia traffic is realized by switching the traffic data to be used according to the traffic to be transmitted.

For example, as audio data, "ITU-
The coded data of the telephone band coding method recommended in the "TG series" is prepared as a standard data template. For audio data, the G.323 format in the H323 encoding format is used. 723.
1 is often used. The bit rates of these encoding formats are determined in advance by constants. 72
In the case of 3.1, there are two types, 6.3 kbps and 5.3 kbps. Output data is 30msec (millisecond)
The intervals are 192 bits (6.3 kbps) and 160 bits (5.3 kbps). The result of encoding several minutes to several tens of minutes of speech is stored in the traffic data storage unit 2 as traffic data. For example, if the sound is about 10 minutes, a small amount of data of about 5 Mbytes may be used. Similarly, for moving image data, the result of encoding like MPEG1 and MPEG2 is stored as traffic data.

In this way, since the traffic data for each multimedia can be stored, the traffic data stored in the traffic data storage unit 2 is encoded according to the new encoding format even for a newly introduced encoding format. It can be easily handled simply by adding it. This traffic data is encoded template data and does not need to be encoded in real time. Therefore, the circuit scale for encoding can be reduced.

FIG. 2 shows an example of a hardware configuration for realizing the apparatus shown in FIG. Traffic load generator 1
Is realized by the CPU 40 and a program stored in the memory 41. The RTC 42 is a real-time clock that measures real time. Magnetic disk device 43
Has a traffic data storage unit 2 and stores a standard data template corresponding to the type of multimedia.
The script input device 3 is realized by a display 44, a keyboard 45, and the like. The NIC (network interface card) 46 is a network interface card that controls transmission and reception of data to and from a network.

When transmitting traffic data to an external network, the CPU 40 reads data from the traffic data storage unit 2 of the magnetic disk device 43 onto the memory 41, and sequentially transmits the data on the memory to transmission parameters specified by a script. The packet data is transferred from the memory 41 to the NI
Transfer to the buffer of C46. By this, NIC4
6 transmits a packet according to a predetermined protocol.

FIG. 3 is a processing flowchart of the apparatus shown in FIG. The transmission procedure / quality setting unit 11 specifies traffic and its quality as transmission instructions based on the script input from the script input device 3 (step S).
1).

The contents of the script define the transmission procedure and have the following data structure. A number of scripts according to this data structure can be specified at one time. [Example of script data structure] (traffic data, transmission start time [msec], transmission time [msec
c], transmission rate [bps], IP address (6 bytes), netmask (6 bytes), drop probability (random / constant)) Basically, only by specifying the transmission start time and destination IP address Traffic can be started to be transmitted.
The transmission start time for a plurality of terminals is replaced with a relative time from the start of transmission to the first terminal.

Since the traffic data is already encoded and stored in the traffic data storage unit 2, the transmission procedure / quality setting unit 11 can confirm or select the traffic data in a list format. The transmission procedure / quality setting unit 11 has an interface that can be visually confirmed in a list. In the present embodiment, a script can be input as a string of text data from the script input device 3, and can also be input interactively by menu selection using a GUI or the like.

The transmission time is automatically determined from the transmission rate since the stored traffic data length is fixed. Further, by extending the transmission time, data transmission can be repeated.

The MAC address resolution section 12 creates an address conversion table for the IP address and the MAC address (step S2). Here, when generating traffic to a plurality of terminals, a plurality of IP addresses are designated by a script, but a MAC address is also required for transmission to Ethernet. IP address (4 bytes) and MAC
ARP (Address)
Resolution Protocol), and creates an address translation table in which two addresses are paired.

The traffic generator 13 loads the traffic data (audio data, image data, etc.) from the traffic data storage 2 into the memory (step S3),
The amount of data to be transmitted at one time is determined from the traffic quality (step S4), and transfer to the terminal is started (step S5).

In the transfer process for the terminal, as shown in FIG. 3B, the real-time clock (RTC) is monitored, and if the transmission time or the transmission time interval is exceeded (step S51), the generation of the packet is performed. It is determined whether or not the packet is lost (step S52). If a packet is generated, the packet is transferred with a header added (step S53). If the packet is lost, the packet is discarded without being generated (step S54). In order to create a transmission log later, transmission information such as time information (RTC information), packet length, and packet loss at this time is left in the memory (step S55). Thereafter, it is determined whether or not the transfer is completed based on whether or not all the data to be transmitted has been transferred, or whether or not a designated transfer end time has been reached. to continue.

When the transfer is completed, the transmission log creating unit 14
Thus, a transmission log is created in a file from the transmission information left in the memory (step S6). That is, since transmission information such as RTC information, packet length, loss, and the like is left in the memory during transmission, after transmission is completed, a series of information is collected from the time of transmission to create a transmission log file. The transmission rate and transmission delay can be obtained from the transmission log.

In the addition of the header in step S53, the header is attached by distinguishing three types of protocols (IP, UDP, and RT) according to the specification of the script and the standard of the data to be transmitted. The data structure of the header is IET
F (Internet Engineering Ta)
SK Force) RFC (Request Fo)
r Comments).
Referring to the address conversion table already associated by the MAC address resolution unit 12, the
An AC address is acquired, and a necessary MAC address is attached to the Ethernet frame data finally transmitted to the network. RTP, UDP, IP, Ethe
A header is attached in the order of rframe to make Ethernet frame data.

In order to simulate a packet loss, a transfer counter is prepared for each terminal, and the transfer counter is increased by one each time one Ethernet frame data is transmitted. An arbitrary constant is determined based on the probability specified in the script, and the packet is discarded when the transfer counter is multiplied by the constant. For example, if transmission is specified at 99.5%, five Ethernet frame data are discarded during 1000 times, but if constant is specified, one Ethernet frame is discarded every 200 times. I do. If the designation of random is made, designation can be made such that five are discarded consecutively at a time, or four are discarded first, and then one is discarded at another timing.

For transmission, one Ethernet frame data waiting to be transmitted is formed in the memory when the header is attached. By copying this Ethernet frame data to the memory of the network interface card (NIC), the network interface card is copied. Sends data. Whether or not this Ethernet frame data received by the network interface card is transmitted
If the difference between the previously transmitted RTC information and the currently transmitted RTC information exceeds the transmission interval, it is transmitted. RTC can obtain relative time in microseconds.

As described above, the traffic load generating device 1 can specify the packet contents, and as a result, the packet length is determined, and controls the generation of traffic by specifying the transmission time interval.

Also, different media data can be packetized and multiplexed as a plurality of traffics, and the mixed packets can be transmitted from any of a plurality of transmitting ports. For example, G
igabitEthernet light transmission port and 10Ba
se-T, 100Base-TX Ethernet
Equipped with multiple (registered trademark) module transmission ports. Appropriate cables are inserted into these transmission ports, and one of them is inserted into the port of the other receiver and used. As a result, a plurality of different media such as audio data and image data can be simultaneously transmitted via the same network. For example, G.
When 1,000 pieces of audio data in the 723.1 encoding format are simultaneously output, the data rate is 6.3 Mbps, but it can be sufficiently transferred even with ordinary Ethernet.

Further, according to the present invention, it is possible to specify the quality of traffic in what order and from which transmitting port by using a script, and to transmit the traffic in the order of the script. Can be transmitted in order by designating the time.

In addition, a packet to be transmitted is generated based on traffic data. The packet can be generated by using a UDP or RTP protocol, which is an upper layer of the network, based on IP as a network protocol. When finally transmitting to the network, it is framed and transmitted to Ethernet. In this way, mutual communication with other Internet equipment is enabled. For example, in the case of audio data (G.723.1), 30
What is necessary is just to convert the 192-bit data into an IP packet every millisecond, and attach the UDP and RTP headers and order them.

Instead of transmitting the generated packet as it is, the packet may be buffered once and then transmitted after changing the transmission order. In the current Internet, since the order of arrival of packets cannot be guaranteed, by making it possible to arbitrarily change the order of transmission, it is possible to reproduce a situation similar to that. Further, by setting the transmission data to be lost, it can be set so that the data is not completely transmitted. For example, it is possible to buffer the packets generated in time series once and change the transmission order by using a script, or to stochastically discard the buffered packets and transmit incomplete data.

Also, by using the generated transmission log file, the output result such as the order of the data frame of the transmission log is obtained.
By comparing the log with the log on the receiving side, it is possible to easily detect illegal data and the like.

The features of the present apparatus are as follows. (a) It has a function to send data to the network while adjusting the amount of traffic data. (b) In order to send out multimedia traffic consisting of images and sounds, it has a function to specify and send a traffic pattern using parameters that conform to the image and sound standards. (c) It has a function to store multimedia traffic data as a template in order to generate multimedia traffic conforming to the video and audio standards. (d) It has the function of simultaneously generating a plurality of different multimedia traffic for each image and audio standard and sending it to the network. (e) It has a function to control the generation of traffic according to a simple script that can specify the bandwidth used for traffic and the transmission order on the time axis. (f) A function to specify the packet data content, the packet sending interval, the packet length, and the maximum number of transmitted packets for the purpose of putting a load on the network without being limited to multimedia traffic. (g) The output device has a function of transmitting data in the upper layer UDP and RTP protocols based on the Internet Protocol (IP) generally used in the Internet. (h) Connect to the network by the same means as the network adapter, and use Ethernet, GigabitEthe
It is also possible to send it out as a physical electrical signal on a network such as rnet. (i) For the purpose of imitating the behavior of the transmission packet on the Internet, it has a function of appropriately changing the transmission order of the packet or transmitting the packet with a pseudo loss of the packet. (j) In addition, it has a function that semi-automatically performs various traffics for the execution of load tests and endurance tests using a simple script, and saves the results as a log.

[0036]

As described above, according to the present invention, it is possible to realize an apparatus for generating a specific multimedia traffic and generating a network load. As a result, a multimedia traffic test can be easily performed, and a durability test and a network load test of a network device can be performed.

Without actually preparing a large number of applications for testing multimedia traffic,
Many pseudo traffic can be generated. In addition, since the transmission data can be lost or changed for each packet constituting the traffic data, it is possible to make the actual transmission packet behave as if it has passed through the Internet. Can help.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an example of a block configuration according to the present invention.

FIG. 2 is a diagram illustrating an example of a hardware configuration of the device illustrated in FIG. 1;

FIG. 3 is a diagram showing a processing flow of the apparatus shown in FIG. 1;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 traffic load generation device 11 transmission procedure / quality setting unit 12 MAC address resolution unit 13 traffic generation unit 14 transmission log generation unit 2 traffic data storage unit 3 script input device

Claims (7)

[Claims] 1. An apparatus for generating a traffic load of a network handling multimedia, comprising: a traffic data storage unit for storing a plurality of traffic data generated in accordance with various standards as a template; and a traffic for generating a traffic load. A transmission procedure / quality setting means for setting a data transmission procedure / traffic quality; and one or more pieces of traffic data read from the traffic data storage means, and a header included in the traffic data based on the set transmission procedure / traffic quality. And a traffic generating means for packetizing the packet and sending the packet to a network. 2. The multimedia traffic load generating device according to claim 1, wherein said traffic data stored in said traffic data storage means is data encoded in advance in a predetermined encoding format for each medium. Multimedia traffic load generator characterized by the following. 3. The multimedia traffic load generating apparatus according to claim 1, further comprising script input means for inputting a script capable of specifying at least a traffic use band and a transmission order on a time axis. A multimedia traffic load generating device, wherein the procedure / quality setting means sets a transmission procedure / traffic quality based on a script input by the script input means. 4. The multimedia traffic load generating device according to claim 3, wherein, when the script includes an instruction to delete a packet to be transmitted, the traffic generating unit performs the transmission procedure / quality setting. A multimedia traffic load generating apparatus, wherein a packet is artificially lost and transmitted based on a setting of a means. 5. The multimedia traffic load generating device according to claim 1, further comprising a transmission log generating unit for generating and recording a transmission log based on information of a result transmitted by said traffic generating unit. Multimedia traffic load generator. 6. A method for generating a traffic load of a network that handles multimedia, wherein traffic data for each of a plurality of media generated in advance according to various standards is held as a template, and is specified by a script defining a transmission procedure. Based on the information
A method for generating a multimedia traffic load, comprising generating a packet by attaching a header corresponding to a protocol to traffic data of a corresponding medium, and transmitting the packet to a network. 7. A recording medium on which a program for generating a traffic load of a network handling multimedia is recorded, wherein a transmission procedure and traffic quality of traffic data at the time of generating a traffic load are determined according to a designated script. Setting processing and reading one or a plurality of traffic data from a means for holding a plurality of traffic data generated in accordance with various standards as a template, and attaching a header to the traffic data based on the set transmission procedure / traffic quality A program recording medium for generating a traffic load, characterized by recording a program for causing a computer to execute a process of packetizing the packet and transmitting the packet to a network.