JPH07152668A - Information processor and communication method - Google Patents

Abstract

PURPOSE:To supply data within a restricted time by compressing the data on the basis of how much a communication network is congested when the data having time restrictions are transferred. CONSTITUTION:When a data request from a client program 4 is inputted to a data request acceptance part 20, a network reception part 21 sends the data request to a network transmission part 26. A data management part 28 acquires the data to be supplied from a secondary storage device 8 or main memory 9 on the basis of retrieval information included in the data request. An access method selection part 27 transfers the data to be supplied to the network transmission part 26 as they are when the quality of specified information included in the data request is given priority. When the time of the specified information is given priority, the data to be supplied to the access method selection part 27 are transferred to a data compression part 30 and processed by a compression and thinning-out method selected according to how much the network line is congested, and then transferred to the network transmission part 26.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information processing device and a communication method for performing data communication with an external device via a communication network.

[0002]

2. Description of the Related Art Conventionally, there is an information processing apparatus capable of accessing a data supply program of a database of another information processing apparatus via a network such as Ethernet.

In this type of information processing apparatus, a network line serving as a shared resource exists in the data transfer path from the data supply side (database or the like) to the data request side.
A plurality of other information processing devices are connected to this network line and used as a data transfer path. Therefore, the time until the data request side acquires the data changes depending on the congestion of data transfer in the network.

[0004]

Some data requested by the data requesting side has a time constraint in acquiring the data. For example, moving image data and the like have real-time properties and lose their value unless data is supplied within a certain fixed time. For this type of data, it is more important that the data arrives within the time, even if the quality is slightly degraded (such as the resolution is reduced and the data amount is reduced) rather than the quality of the data (image quality in the case of image data etc.). Become.

However, in the conventional information processing apparatus, even when handling data having a time constraint, only the quality of the data is emphasized and all the data are transferred. Therefore, depending on the congestion of the network, a situation occurs in which data cannot be supplied to the data requesting side within the required time.

The present invention has been made in view of the above problems, and when transferring data with a time constraint,
An object of the present invention is to provide an information processing method and an apparatus and a communication method thereof that can perform data compression or the like based on the congestion degree of a communication network and supply the data within a limited time.

[0007]

In order to achieve the above object, an information processing device on the data receiving side of the present invention has the following configuration. That is, an information processing device that performs data communication with another device connected via a communication network,
Requesting means for requesting data to the other device,
Receiving means for receiving data representing the request of the requesting means and information indicating the compression state of the data from the other device via the communication network, and decompressing the data based on the information indicating the compression state. And a restoring means for performing.

An information processing apparatus on the data supply side according to the present invention for achieving the above object has the following configuration. That is, an information processing device that performs data communication with another device connected via a communication network, and acquires the congestion degree of the line with an acquisition unit that acquires data according to a data request from the other device. The determination means for determining, the compression means for compressing the data acquired by the acquisition means, and the data compressed by the compression means based on the determination result by the determination means are added with information indicating the compression state. And a transmitting means for transmitting to the other external device.

Further, the communication method of the present invention which achieves the above-mentioned object includes the following steps. That is, a communication method between first and second information processing apparatuses connected by a communication network, the request step of requesting data from the first information processing apparatus to the second information processing apparatus An acquisition step of acquiring data to be provided by the second information processing device in response to the request of the request step, a determination step of determining the congestion degree of the communication network, and the determination step of the determination step. A compression step of compressing the data acquired in the acquisition step according to the congestion degree of the communication network, and information indicating the compression state is added to the data compressed in the compression step and transmitted to the first information processing device. And a receiving step of receiving the data transmitted in the transmitting step in the first information processing apparatus, and compressing the data received in the first information processing apparatus. And a storage step of storing the same to restore on the basis of the information indicating the condition.

[0010]

With the above-described configuration or process, the information processing apparatus on the data supply side performs data compression processing according to the congestion level on the communication network, and adds the information indicating the compression state to the data transmission. . Therefore, the information processing device on the data receiving side can more reliably receive the data even when the line is congested. Further, the information processing device on the data receiving side appropriately restores the compressed data based on the information indicating the compression state.

[0011]

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a block diagram showing a schematic functional configuration of the information processing system of this embodiment. In the figure, 1
Is a computer on the data requesting side, makes a data request, and provides the obtained data to the client program. A computer and a computer 2 on which a part of the program for supplying data operates, and a computer 2 on the data supply side receives a data request and supplies the data to the request source. A network line 3 connects the computer 1 and the computer 2. An example of the network line 3 is Ethernet. It goes without saying that an information processing device other than the computers 1 and 2 may be connected to the network line 3.

Reference numeral 4 denotes a client program which operates on the computer 1 and makes a data request to display a moving image or the like. A display device 5 is used for displaying a moving image by the client program 4. A parent server program 6 runs on the computer 2, manages various data, and controls network communication to supply data. The parent server program 6 compresses or thins out the data to be supplied based on the congestion of the data communication on the network line. A child server program 7 operates on the computer 1 and receives the data output by the parent server program 6 of the computer 2 via the network line 3 in accordance with the data request from the client program 4. Here, the child server program 7
When the supplied data has been compressed or thinned by the parent server program 6, the data is supplied to the client program 4 after decompression and interpolation.

A secondary storage device 8 stores various data. Reference numeral 9 denotes a main memory, which provides an area for the parent server program 6 to store and manage data. The main memory 9 may be used as a cache for the secondary storage device 8. Further, depending on the nature of the data, those that require high-speed access may be stored in the main memory 9, and those that do not need to be stored in the secondary storage device 8 may be used separately.

Reference numeral 10 denotes a buffer memory, which is used until the child server program 7 transfers the data received from the parent server program 6 to the client program 4.
Store it temporarily. An inter-program communication function 11 provides a local data transfer means between the client program 4 and the child server program 7. Specifically, it is a high-speed inter-program (process) communication function capable of predicting the maximum transfer time, such as a shared memory communication mechanism provided by an OS or the like running on the computer 1.

FIG. 2 is a block diagram showing a schematic hardware configuration for realizing the above-described functional configuration. First calculator 1
The configuration of will be described. In the figure, 101 is a CP
U, which executes a control program (child server program 7 or the like) stored in the ROM 102 or the RAM 103. A ROM 102 stores various control programs, data, and the like. 103 is a RAM,
In addition to storing the client program 4 and the child server program 7 described above, it also provides an area as a buffer memory 10. An interface circuit 104 connects the network line 3 and the system bus 105.

The computer 2 also has a CPU 201 and a RON 20.
2, the RAM 203, the interface circuit 204, the system bus 205, and the like have the same configuration as the computer 1. However, the RAM 203 is the parent server program 6
And an area as the main memory 9 is provided.

FIG. 3 is a block diagram showing details of the functional configurations of the parent server program 6 and the child server program 7.

In the figure, reference numeral 20 denotes a data request receiving unit, which receives a data request from the client program 4. The data request accepted here includes search information that specifies the data to be searched, and specification information that specifies whether the data is supplied with time priority or quality priority. Reference numeral 21 denotes a network reception unit, which is used to control various control data with the parent server program 6 (specification information of quality priority or time priority, acknowledgment of data reception, number of buffering data, search information, etc.).
Network line 3 for sending and receiving data and receiving data
Through. A data discriminating unit 22 discriminates whether the received data is compressed or thinned data or not. A data decompression unit 23 decompresses and interpolates when the data is compressed or decimated. Two
A buffering unit 4 temporarily buffers data in the child server program 7. A data supply unit 25 supplies data to the client program 4 through the inter-program communication function 11.

Reference numeral 26 denotes a network transmission unit, which transmits / receives control data and data to / from the child server program 7 via the network line 3. An access method selection unit 27 selects a data access method depending on whether the client program 4 selects quality priority or time priority. 28 is a data management unit,
Various data is stored in the secondary storage device 8 and the main memory 9, and the stored data is managed and searched. Reference numeral 29 is a compression method determination unit, and the network line 3
The data compression or thinning is performed based on the congestion level or the number of data buffered in the child server program 7, or when the data to be transferred contains a compression method. Determine how to do it. A data compression unit 30 has a plurality of compression methods and thinning methods. The data compression unit 30 executes data compression by the compression method or the thinning method selected based on the determination result of the compression method determination unit 29.

In the information processing system of the present embodiment having the above-mentioned configuration, when the data request from the client program 4 is input to the data request accepting unit 20, the network receiving unit 21 sends the data request to the network transmitting unit 26. To be done. The data management unit 28 acquires the data to be supplied from the secondary storage device 8 or the main memory 9 based on the search information included in the data request. If the designation information included in the data request has quality priority, the access method selection unit 27 transfers the data to be supplied to the network transmission unit 26 as it is. Further, if the designation information is time priority, the access selection unit 27 determines the data to be supplied by the data compression unit 3.
Transfer to 0. The data compression unit 30 selects a compression / thinning method according to the congestion level of the network line.
Then, the data compression unit 30 applies the selected compression / thinning to the data to be supplied, and then transfers the data to the network transmission unit 26.

The network receiving section 21 transfers the provided data to the data discriminating section 22. Data discriminator 2
2 judges whether or not the transferred data is compressed / thinned. If not compressed / thinned, the buffering unit 24 fart data is transferred and stored in the buffer memory 10 as it is. On the other hand, if compression / thinning has been performed, the data is transferred to the data decompression unit 23, decompressed / interpolated, and then stored in the buffer memory 10 via the buffering unit 24. Then, the data supply unit 25 takes out the data stored in the buffer memory 10 and supplies it to the client program 4.

Next, the operation of this embodiment will be described in more detail with reference to the attached flow chart. 4 and 5 are flow charts for explaining the operation procedure of this embodiment.

In step S11 of FIG. 4, when a data request from the client program 4 is input to the data request receiving unit 20, the process proceeds to step S12. here,
The data request from the client program 4 includes search information necessary for data search, designation information of time priority or quality priority, and the like. Further, when the time priority is designated in the designation information, information such as the time constraint is also passed. The child time constraint information is, for example, in the case of moving image data, information that one frame of data should be continuously supplied in 1/30 seconds. Step S1
In 2, the information (data request) is transferred to the parent server program 6 by the network receiving means 21. Then, in step S13, it waits for the data to be transmitted from the parent server program.

Next, the operation of the parent server program 6 to which the data request is input will be described with reference to FIG.

In step S31, the information transferred from the child server program 7 is received by the network transmission unit 26 of the parent server program 6. Then, the search information is transferred to the data management unit 28, and the designation information is transferred to the access method selection unit 27. In step S32, the data management unit 28 performs a data search of the secondary storage device 8 and the main memory 9 based on the received search information, and delivers the searched data to the access method selection means 7.

In step S33, the access method selection unit 27 transfers the data transferred from the data management unit 28 based on the designation information designating time priority or quality priority. Here, the read data is transferred to the data compression unit 30 if the time is prioritized, and to the network transmission unit 26 if the quality is prioritized.

If the quality is prioritized, the process proceeds from step S33 to step S39, and the read data is transferred to the computer 1 as it is via the network transmission unit 26. On the other hand, when the time priority is designated in step S33, the processes of step S34 and subsequent steps are performed.

In step S34, the compression method determination unit 29 determines the congestion level of the network line 3 and determines the compression / thinning level. Here, as the determination method for determining the compression / thinning level, (1) the congestion level of the line is determined based on the degree of delay of the arrival time of the acknowledgment from the child server 1, and the compression (2) Buffer memory 1 in the child server 1 that determines the level
The congestion level of the line is determined based on the amount of data remaining in 0, and the compression level is determined. (3) If the information that specifies compression / thinning is added to the read data, it is based on that information. To determine the level of compression.

In subsequent steps S35 to S38, the data compression unit 30 performs processing such as compression and thinning on the provided data according to the compression / thinning level determined by the compression method determination unit 29. Network line 3
If it is determined that compression and thinning are not necessary, the process proceeds from step S36 to step S39, and the data is transferred to the child server 1 as it is. Step S3
In 7, the compression / thinning process is performed according to the level determined by the compression method determination unit 29. For example, network line 3
Is very crowded, and if high level compression / decimation is required, the resolution will be lower than that of data decimation.
When low-level compression or thinning is requested, compression is performed based on the difference from the previous frame.

Further, the data compressing means 30 executes the compression or the like based on the judgment result of the compression method judging means 29, but does not execute the compression or the like because there is no information such as the congestion degree of the network at the start of data transmission. Transmission will start. However, while continuing data transmission thereafter, the arrival time of the acknowledgment sent from the child server 1 may be delayed, or the buffer memory 10 in the child server 1 may be delayed.
On the basis of the information on the number of data buffered in, the compression method determination means 29 selects whether or not to perform data compression or thinning, and the method. If the acknowledgment arrives slowly or the number of buffered data is less than a certain empirically determined level, the network line 3
It is judged that the data cannot be supplied within the requested time due to congestion, and the data is compressed or thinned,
Reduce the amount of transfer data so that data can be supplied in time.

As described above, the compression or thinning method is selected by selecting a method suitable for the congestion based on the determination result of the congestion degree of the network line 3. In other words, if it is determined that the network line 3 is very busy and the number of transfer data has to be significantly reduced, it is not necessary to select a compression method having a high compression rate even if the quality is deteriorated, and not to reduce that much. If you decide,
Select a compression method with a low compression rate.

The compression method may be described in advance in the data. For example, if the data is moving image data and you want to significantly reduce the number of transferred data, reduce the resolution of the frame data, and if you do not need to reduce that much, compress based on the difference from the previous frame. Information is added inside the data in advance. If such information is added, the compression / thinning method according to the information is selected.

As described above, in step S37,
The data compression unit 30 performs data compression and thinning processing based on the determination result of the compression method determination unit 29. If the data is actually compressed or thinned out, step S
In 38, information (compression information) indicating which method has been used for compression / thinning is added to the data. Based on this compression information, the child server program 7 selects and executes the decompression / interpolation method suitable for each data.

As described above, when the quality priority is requested, all the data is directly transferred from the access method selection unit 27 to the network transmission unit 26. When the time priority is requested, the data is passed to the network transmission unit 26 through the data compression unit 30. And step S3
At 9, the network transmission unit 26 transfers the delivered data to the child server 1 through the network line 3.

In the following step S40, an acknowledgment is waited for from the child server 1 of the data transmission destination, and when the acknowledgment is received, the process proceeds to step S41. In step S41, the response time of this acknowledgment is acquired and stored. Regarding the response time of the acknowledgment, start the program for measuring the time with the data transfer in step S39, etc.
You can use a general method.

Next, the data receiving operation of the child server program 7 (after step S13 in FIG. 4) will be described.
In step S13, the network receiving unit 21
When data is received from the parent server program 6 through the network line 3, the process proceeds to step S14. Step S
At 14, the acknowledgment is transmitted to the parent server 2. This acknowledgment is referred to in step S40 described above. In step S15, the received data is transferred to the data discriminating unit 22, and it is determined whether or not the data is compressed / thinned. This determination is made by referring to the information added in step S38. Here, the data discriminating unit 22 determines whether the data is compressed / thinned or not by the network receiving unit 2
It is determined whether or not there is compression information added to the data received from 1. Then, if there is compression information, it is passed to the data decompression unit 23 as data that has been compressed and thinned (that is, proceeds to step S16). If there is no compressed information, it is directly transferred to the buffering unit 24 (that is, the process proceeds to step S18).

In step S16, the data decompression unit 23 that has received the data determines the decompression / interpolation process to be applied based on the compression information added to the data. Then, in step S17, decompression / interpolation processing is executed, and the obtained data is transferred to the buffering unit 24. In step S18, the buffering unit 24
Stores the received data in the buffer memory 10. The data supply unit 25 uses the client program 4
When a request to receive data is received from the buffer memory 10, it is taken out from the buffer memory 10. In step S19, the compression method determination unit 29 in the parent server program 6
In order to give information necessary for determining the compression method, information on the number of data buffered in the buffer memory 10 is transmitted to the parent server program 6 through the network receiving unit 21.

As a method of notifying the amount of buffered data, the following method may be used in addition to transmitting the number of data at that time each time the buffering process is performed as in this example. That is, the information indicating that may be transmitted only when the number of buffered data becomes lower than a certain level determined empirically and when the number of data is returned to that level. Also, the buffer memory 1
When 0 is about to overflow, the parent server program 6
The flow control is also executed such that the data transmission is stopped further, and when the danger disappears, the data transmission is restarted.

The data supply unit 25 issues a data reception request to the buffering unit 24 and receives the data according to the information on the access method of the data received by the data request reception unit 20. The data is supplied to the client program 4 through the inter-program communication function 11. For example, if the data requested by the client program 4 is data such as a moving image, and the access method is a request to supply one frame of data in 1/30 seconds, the data supply unit 25 The time is controlled, and the buffering unit 24 is 1 / 30th.
A reception request for receiving one frame of data is issued at second intervals. In this way, data is received at 1/30 second intervals and supplied to the client program 4 through the inter-program communication function 11.

As described above, according to the present embodiment, by making a data request with priority on time, it is possible to acquire data within a predetermined time regardless of the congestion degree of the network line. For example, when the client program 4 accesses real-time data such as moving image data, the data request is made with priority to time. Then, by designating a time constraint such as 1 frame of data for 1/30 second, data can be received from the child server program 7 in accordance with the requested time constraint. Therefore, it becomes possible to display an image on the display device 5 or the like while maintaining the real-time property.

When it is desired to access all data with priority on quality as in the conventional case, data may be requested with priority on quality, and data can be supplied in an optimum manner according to the request of the client program 4.

Further, as is apparent from the above description, according to this embodiment, the above-mentioned processing can be executed without requiring special hardware.

As described above, according to this embodiment,
When requesting data from a data supply program on another computer connected via a network, access should be performed with priority given to data supply within a certain time even if quality is degraded, or it may take a long time. It is possible to specify whether to access with priority on quality such as wanting to supply all data without degrading quality. Therefore, when a data request is made with priority on time, it becomes possible to receive data according to the requested time constraint. In this way, an information processing system capable of supplying data in an optimum manner according to the request of the data request program can be obtained.

The present invention may be applied to a system composed of a plurality of devices or an apparatus composed of a single device. Further, it goes without saying that the present invention can be applied to the case where it is achieved by supplying a program to a system or an apparatus.

[0046]

As described above, according to the present invention, when transferring data with a time constraint, the data is compressed or the like based on the congestion degree of the communication network, and the data is transferred within the restricted time. Can be supplied.

[0047]

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic functional configuration of an information processing system of this embodiment.

FIG. 2 is a block diagram showing a schematic hardware configuration for realizing the functional configuration of the present embodiment.

FIG. 3 shows a parent server program 6 and a child server program 7.
3 is a block diagram showing the details of the functional configuration of FIG.

FIG. 4 is a flowchart illustrating an operation procedure of this embodiment.

FIG. 5 is a flowchart illustrating an operation procedure of this embodiment.

[Explanation of symbols]

 1 computer (data request side) 2 computer (data supply side) 3 network line 4 client program 5 display device 6 parent server program 7 child server program 8 secondary storage device 9 main memory 10 buffer memory 11 inter-program communication function

Claims (9)

[Claims] 1. An information processing device for performing data communication with another device connected via a communication network, comprising: requesting means for requesting data to the other device; and request by the requesting means. Receiving means for receiving the corresponding data and information indicating the compression state of the data from the other device via the communication network, and decompression means for decompressing the data based on the information indicating the compression state. An information processing device comprising: 2. The information processing apparatus according to claim 1, further comprising a transmitting unit that transmits to the other device that the receiving unit has received the data. 3. Further comprising buffer means for storing the data obtained by said restoring means, and second transfer means for transferring information based on the amount of data stored by said buffer means to said another device. The information processing apparatus according to claim 1, wherein: 4. An information processing device for performing data communication with another device connected via a communication network, the acquisition device acquiring data according to a data request from the other device, Information for indicating the compression state of the data compressed by the compression means, the compression means for compressing the data acquired by the acquisition means based on the determination result by the determination means An information processing apparatus, comprising: a transmission unit that adds the information to the external apparatus and transmits the transmission to the other external apparatus. 5. The determination means determines the congestion level of the line based on a delay time of a response signal from the other external device to the data transmitted from the device. The information processing device according to 1. 6. The determination means determines the congestion degree of the line based on the amount of data transmitted from the transmission means accumulated in the other external device. The information processing device according to 1. 7. A communication method between first and second information processing apparatuses connected by a communication network, wherein a data request is made from the first information processing apparatus to the second information processing apparatus. A requesting step to be performed, an acquiring step of acquiring data to be provided by the second information processing device in response to the request from the requesting step, a determining step of determining a congestion degree of the communication network, and a determining step of the determining step A compression step of compressing the data acquired in the acquisition step according to the congestion degree of the communication network, and the first information processing by adding information indicating the compression state to the data compressed in the compression step. A transmitting step of transmitting to the apparatus, a receiving step of receiving the data transmitted in the transmitting step in the first information processing apparatus, and the data received in the first information processing apparatus , A communication method characterized by comprising a storage step of storing the same to restore on the basis of the information indicating the compressed state. 8. When the first information processing apparatus receives the data transmitted in the receiving step, a response step of transmitting a response signal to that effect to the second information processing apparatus is included. The communication method according to claim 7, further comprising: the determining step determining a congestion degree of the communication network based on a delay in arrival of the response signal. 9. The method further comprises a notifying step of notifying the second information processing device of the amount of data stored in the storing step, and the determining step includes the amount of data notified by the notifying step. The communication method according to claim 7, wherein the congestion degree of the communication network is determined based on the.