JP2002176451A - Communication method, communication equipment, client unit, cache server device and recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To distribute the processing load of a server device. SOLUTION: In the case that the cache server device 3 intervenes communication between a client unit 1 and a 1st server device being an access destination, the cache server device 3 conducts distribution processing (101) that always distributes data sent from the 1st server device and stored in the cache server device 3 to the client unit 1. The client unit 1 conducts reception storage processing (103) that receives the data distributed from the cache server device 3 on the occurrence of a message of requesting the data from the client unit 1 (102) and conducts transfer processing (104, 105) that transmit the message to the cache server device 3 when the client unit 1 has not data requested by the message among the stored data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a client-server communication technology via a cache server device.
In particular, the present invention relates to a communication method, a communication device, a client device, a cache server device, and a recording medium capable of distributing a processing load of a server device.

[0002]

2. Description of the Related Art Conventionally, as a method for assisting communication between a client device and a server device, there is a communication method for performing communication between a client and a server via a cache server device. An example of such a communication method is described in the document "" UNIX.
(Registered Trademark) Communication Note
s 145 ", Unix Magazine 200
0.7 Monthly, ASCII Publishing Co., Ltd. "and many other documents. FIG. 21 is a block diagram showing the configuration of a conventional communication device for realizing client-server communication via a cache server.

[0003] The cache server device 1003 is composed of a client device 1001 and, for example, a client device 1001.
And a server device 1002 for providing digital content to the server. When data not stored in the cache server device 1003 is transmitted from the server device 1002 to the client device 1001, the cache server device 1003 stores the data (FIG. 21).
(A)). After storing the data, the other client devices 100
When the same data request is issued from 1a or the like, the data stored in the cache server device 1003 is transmitted in place of the server device 1002 (FIG. 21B). Through such processing, it is possible to reduce the bandwidth and speed up the reply.

FIG. 22 shows a processing sequence as described above. When a data transmission request (request) is generated from the client device 1001 (step 2101), a request message indicating this request is sent to the cache server device 1003 (step 2102). The cache server device 1003 determines whether or not the data requested by the request message is stored (step 2103), and if the data exists, returns the data requested by the request message (step 210).
4) If there is no data, request the server device 1002 for data (step 2105). Server device 100
2 stores the requested data in the cache server device 100
3 (step 2106), the cache server device 1003 stores the received data (step 2107), and then returns the data to the client device 1001 (step 2108).

FIG. 23 shows a conventional client device 1001.
FIG. 24 shows a conventional cache server device 1.
003 is shown. The client device 1001 includes a data display unit 1011 such as a browser and a data display unit 10.
Accepts the request message input from 11,
A user request transmission unit 1012 for transmitting this,
This request message is sent to the cache server device 10
And a network communication unit 1013 for transmitting the data to the network 03. The cache server device 1003 receives a request message from the client device 1001,
A network communication unit 1031 for communicating with another server device, and a data storage unit 103 for storing data
2 and a request search unit 1033 for searching whether the data requested by the request message exists in the data storage unit 1032.

In order to improve the efficiency of the cache servers, if the first cache server (local cache server) does not have the data requested by the request message, another cache server (center cache server) is used. A multi-stage cache system that sends a request message to a client has been proposed.
A typical example of such a multi-stage cache communication method is SQUID (http://www.squid-cache.org).

FIG. 25 shows a configuration of a conventional communication device using a multi-stage cache, and FIG. 26 shows a processing sequence of this communication device. When a data transmission request (request) is generated from the client device 1001 (step 310)
1), a request message indicating this request is sent to the local cache server device 1004 (step 3)
102). The local cache server device 1004
It is determined whether or not the data requested by the request message is stored (step 3103). If the data exists, the data requested by the request message is returned (step 3104). A request message is sent to the center cache server 1005 to request data (step 310).
5).

[0008] Center cache server 1005
Determines whether the data requested by the request message is stored (step 3106), and if the data exists, returns the data requested by the request message (step 3107). After accumulating the received data (step 3108), the local cache server device 1004 returns the data to the client device 1001 (step 3109). On the other hand, if there is no data in step 3106, the center cache server
02 is requested for data (step 3110). The server device 1002 returns the requested data (step 3111), and the center cache server device 1005
After storing the received data (step 311
2), the data is transferred to the local cache server device 10
04 is returned (step 3113). Then, after storing the received data (step 3114), the local cache server device 1004 returns this data to the client device 1001 (step 3115).

In addition, the center cache server device is
It is not necessary to use a plurality of servers, and it is also possible to request data from a plurality of center cache server devices. Further, it is possible that another local cache server device plays the role of the center cache server device, but the names are divided here in order to clarify that a request is transmitted in a multi-stage cache configuration.

[0010]

However, in a communication device using an existing cache server, when a large number of client devices are accommodated, requests may be concentrated on one server device. Is concentrated,
There was a problem that all the processing could not be performed. Such a problem occurs in either the communication device using the normal cache shown in FIG. 21 or the communication device using the multi-stage cache described in FIG. The present invention has been made in order to solve the above problems, and has a communication method capable of distributing a processing load of a server device.
It is an object to provide a communication device, a client device, a cache server device, and a recording medium.

[0011]

According to the present invention, there is provided a communication method for mediating communication between a client device (1) and a first server device to be accessed by a cache server device (3). A distribution process (101) for constantly distributing data transmitted from the cache server device and stored in the cache server device to the client device, and a message requesting data from the first server device is transmitted by the client device. When it occurs (102), a reception accumulation process (103) of receiving and accumulating data distributed from the cache server device by the client device, and the data requested by the message exists in the accumulated data. If this is the case, this data is obtained. From Ianto device is obtained to perform the transfer process and (104, 105) to be transmitted to the cache server apparatus. The present invention also provides a communication method for mediating communication between a client device and a first cache server device (5) by a second cache server device (4), wherein the first server to be accessed by the client device is provided. A distribution process for constantly distributing data transmitted from the device and stored in the first cache server device from the first cache server device (201)
If the data requested by the message from the client device is stored in the second cache server device, a reply process of transmitting the data from the second cache server device to the client device (2
03, 204) and a receiving and storing process (205) of receiving and storing data distributed from the first cache server device when the data requested by the message is not stored, If the data requested by the message exists in the data, the data is transmitted to the client device; otherwise, the transfer process transfers the message to the first cache server device (step 206 to 208).

The present invention also provides a client device (1
c) a communication method that mediates communication using the WDM technique between the access destination first server device and the access destination first server device by the cache server device (3c). A transmission wavelength to be allocated to the stored transmission data is determined based on the identification information of the transmission data (step 301), and a distribution process of constantly transmitting the transmission data from the cache server device to the client device at the transmission wavelength ( 30
2) and when a message requesting data from the first server device occurs in the client device (30)
3), a receiving wavelength is determined based on the identification information of the data requested by the message (304), and the data distributed from the cache server device at the receiving wavelength is received and stored by the client device. Processing (3
05), if the data requested by the message is present in the stored data, the data is acquired; otherwise, the message is transmitted from the client device to the cache server device. Transfer processing (306, 307). The present invention also provides a communication method in which communication using a WDM technique between a client device and a first cache server device (5c) is mediated by a second cache server device (4c). A transmission wavelength to be allocated to transmission data transmitted from the first server apparatus and stored in the first cache server apparatus is determined based on the identification information of the transmission data (step 401), and the transmission wavelength is determined. A delivery process (402) for constantly delivering the transmission data from the first cache server device; and a case where data requested by a message from the client device is stored in the second cache server device. Reply processing (4) for transmitting this data from the second cache server device to the client device 4,405), when the data requested by the message is not stored, the receiving wavelength is determined based on the identification information of the data requested by the message (406), and the first wavelength is determined by the receiving wavelength. A receiving and storing process (407) for receiving and storing data distributed from the cache server device, and, when the data requested by the message is present in the stored data, the data is transmitted to the client device. Send,
If the message does not exist, a transfer process of transferring the message to the first cache server (step 408)
To 410).

As one configuration example of the communication method according to the present invention, in the distribution process, the history of a message transmitted from the client device is stored in the cache server device or the first cache server device. The data stored in the cache server device or the first cache server device is transmitted in descending order of requests from the client device. Further, as one configuration example of the communication method according to the present invention, in the distribution process, data stored in the cache server device or the first cache server device is transmitted based on a preset transmission data schedule. It was made.

[0014] In the communication device of the present invention, the cache server device includes means for constantly delivering the data transmitted from the first server device and stored in the cache device to the client device, wherein the client device includes When a message requesting data is issued to one of the server devices, the data received from the cache server device is received and stored, and the data requested by the message is present in the stored data. Comprises means for acquiring the data and transmitting the message to the cache server device when the data does not exist. Further, in the communication device of the present invention, the first cache server device includes means for constantly distributing the data transmitted from the first server device and stored in its own device,
When receiving a message requesting data from a client device, if the data requested by this message is stored in its own device, the cache server device transmits the data to the client device and stores the data. If not, receive and accumulate the data distributed from the first cache server device. If the data requested by the message is present in the accumulated data, this data is Send to the client device, if not present, the message to the first
Means for transferring data to the cache server device.

Further, in the communication device of the present invention, the cache server device determines a transmission wavelength to be allocated to the transmission data transmitted from the first server device and stored therein, based on the identification information of the transmission data. Means for constantly delivering the transmission data to the client device at the transmission wavelength, wherein the client device generates a message requesting data from the first server device,
The receiving wavelength is determined based on the identification information of the data requested in the message, the data distributed from the cache server device is received and stored at the receiving wavelength, and the request is transmitted in the stored data by the message. In the case where there is provided data, the data is acquired, and when the data does not exist, means for transmitting the message to the cache server device is provided. Further, in the communication device of the present invention, the first cache server device determines a transmission wavelength to be allocated to the transmission data transmitted from the first server device and stored in the own device based on the identification information of the transmission data. Means for constantly distributing the transmission data at this transmission wavelength, and when the second cache server device receives a message requesting data from the client device, the second cache server device stores the data requested by this message in its own device. If so, the data is transmitted to the client device.If the data is not stored, the reception wavelength is determined based on the identification information of the data requested in the message. Receiving and storing data distributed from the first cache server device,
When the data requested by the message exists in the stored data, the data is transmitted to the client device. When the data does not exist, the message is transmitted to the first cache server device. Means.

As one configuration example of the communication device of the present invention, the cache server device or the first cache server device accumulates a history of a message transmitted from the client device in its own device, and Means for transmitting data transmitted from one server apparatus and stored in the apparatus in descending order of requests from the client apparatus. Further, as one configuration example of the communication device of the present invention, the cache server device or the first cache server device transmits data transmitted from the first server device and stored in the own device to transmission data set in advance. It has means for transmitting based on a schedule.

Further, the client device (1) of the present invention
The network communication unit (12) for communicating with the cache server device (3) provided between the first server device and the access destination, and a message requesting the first server device for data has occurred. At this time, the user request receiving unit (1) instructs the network communication unit to receive the data distributed from the cache server device.
3), a data storage unit (14) for storing data distributed from the cache server device and received by the network communication unit, and a case where the data requested by the message is stored in the data storage unit. Has a user request determination unit (15) for instructing the network communication unit to acquire the data and transmit the message to the cache server device when the data is not stored. Further, the client device (1c) of the present invention uses the network communication unit (1c) that communicates with the cache server device (3c) provided between the client device and the first server device to be accessed using the WDM technology.
2c), a user request receiving unit (13c) for issuing an instruction to receive data distributed from the cache server device when a message requesting data from the first server device occurs, and responding to the instruction. A receiving wavelength determining unit that determines a receiving wavelength based on the identification information of the data requested in the message, and instructs the network communication unit to receive data distributed from the cache server device at the receiving wavelength. 16), a data storage unit (14) for storing data received by the network communication unit, and if the data requested by the message is stored in the data storage unit, the data is acquired. If the message is not stored, the message is sent to the cache server so as to transmit the message to the cache server device. Those having a user request judgment unit (15c) for instructing the section.

Further, the cache server device (3) of the present invention comprises a first server device and a client device (1).
A network communication unit (31) for communicating with the first communication device;
A data storage unit (32) for storing data transmitted from the server device and received by the network communication unit, and instructing the network communication unit to distribute the data stored in the data storage unit to the client device. And a transmission data determination unit (33). The cache server device (4) of the present invention includes a network communication unit (41) for communicating with another cache server device and a client device, and a data storage unit (42) for storing data received by the network communication unit. )When,
When receiving a message requesting data from the client device, if the data requested by the message is not stored in the data storage unit, the data is transmitted from the first server device that is the access destination of the client device. A user request receiving unit (43) for instructing the network communication unit to receive data stored in another cache server device from the another cache server device; and a data storage unit that stores the data requested by the message in the data storage unit. If the data is stored, the network communication unit is instructed to transmit the data to the client device, and after receiving the data from the another cache server device, the data requested by the message is stored in the data storage unit. If the message is not stored in the Those having a user request judging section (44) to instruct the network communication unit to transfer to the cache server apparatus.

The cache server device (3) of the present invention
c) includes a network communication unit (31c) that communicates with the first server device or the client device (1c) using the WDM technology, and data transmitted from the first server device and received by the network communication unit. (32c), a transmission data determining unit (33c) for instructing the client device to distribute the transmission data stored in the data storage unit, and a transmission data determining unit (33c) in response to the instruction of the transmission data determining unit. And determining a transmission wavelength to be allocated to the transmission data based on the identification information of the transmission data, and instructing the network communication unit to distribute the transmission data to the client device at the transmission wavelength. ). The cache server device (4c) further includes a network communication unit (41c) that communicates with the other cache server device or the client device using WDM technology, and a data unit that stores data received by the network communication unit. When a message requesting data is received from the storage unit and the client device, if the data requested by the message is not stored in the data storage unit, a first access destination of the client device is set. A user request receiving unit (4) for giving an instruction to receive data transmitted from one of the server devices and stored in the other cache server device from the other cache server device.
3c) and, in response to the instruction, determining the reception wavelength based on the identification information of the data requested in the message, and the network is configured to receive the data distributed from the other cache server device at the reception wavelength. A receiving wavelength determining unit (46) for instructing a communication unit, and, when the data requested by the message is stored in the data storage unit, the network communication unit to transmit the data to the client device. And if the data requested by the message is not stored in the data storage unit after receiving the data from the other cache server device, the network is configured to transfer the message to another cache server device. A user request determination unit (44c) for instructing the communication unit.

The recording medium of the present invention is transmitted from the first server device to the cache server device (3) which mediates communication between the client device (1) and the first server device to be accessed. It records a cache server processing program for executing a distribution process (101) for constantly distributing data accumulated in the cache server device to the client device. Further, in the recording medium of the present invention, when a message requesting data to the first server device to be accessed occurs (102), the recording medium is distributed from the cache server device that mediates communication with the first server device. A receiving and storing process (103) for receiving and storing data; and, when the data requested by the message exists in the stored data, the data is acquired. Transfer processing (104, 1) for transmitting
05) is recorded in the client device (1). Further, the recording medium of the present invention stores the data requested by the message from the client device in the second cache server device (4) which mediates communication between the client device and the first cache server device (5). If the data is stored in the second cache server device, a reply process of transmitting the data to the client device (203, 204)
And receiving and storing the data distributed from the first cache server device when the data requested by the message is not stored (205).
If the data requested by the message exists in the stored data, the data is transmitted to the client device; otherwise, the message is transmitted to the first cache server device. A cache server processing program for executing a transfer process (steps 206 to 208) to be transferred is recorded.

Further, the recording medium of the present invention stores the first storage medium in the cache server apparatus (3c) which mediates communication using the WDM technology between the client apparatus (1c) and the first server apparatus to be accessed. The transmission wavelength transmitted from the server device and allocated to the transmission data stored in the cache server device is determined based on the identification information of the transmission data (step 301), and the transmission data is transmitted at the transmission wavelength to the client device. A cache server processing program for executing a distribution process (302) for constantly distributing the content to a cache server is recorded. Further, the recording medium of the present invention,
When a message requesting data is issued to the first server device to be accessed (303), the reception wavelength is determined based on the identification information of the data requested by the message (304), and the cache is determined by the reception wavelength. A receiving and storing process (305) for receiving and storing the data distributed from the server device, and, if the stored data includes the data requested by the message, the data is acquired, and is not present. In this case, the transfer processing for transmitting the message to the cache server device (306, 3
07) are recorded in the client device (1c). Also,
The recording medium of the present invention provides a second cache server device (4c) that mediates communication using WDM technology between a client device and a first cache server device (5c).
When the data requested by the message from the client device is stored in the second cache server device, a reply process (404, 405) for transmitting the data to the client device; If the received data is not stored, the reception wavelength is determined based on the identification information of the data requested in the message (406), and the data distributed from the first cache server device at this reception wavelength is received. Receiving and storing processing (407) for storing the data requested by the message in the stored data, and transmitting the data to the client device if the data does not exist; Transfer processing for transferring to the first cache server device (steps 408 to 410)
Are recorded.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [Embodiment 1] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a block diagram illustrating a configuration of a client device in a communication device according to a first embodiment of the present invention, and FIG. 2 is a block diagram illustrating a configuration of a cache server device in the communication device. Also in the present embodiment, the overall configuration of the communication device is the same as that of the conventional communication device shown in FIG.
In the present embodiment, a method will be described in which a client device receives transmission data from a cache server device and acquires a file.

The client device 1 is provided with a data display unit 11 such as a browser, a network communication unit 12 for communicating with the cache server device 3, and when a request message is input from the data display unit 11, the data is distributed from the cache server device 3. User request receiving unit 1 instructing network communication unit 12 to receive the received data
3, a data storage unit 14 for temporarily storing data distributed from the cache server device 3 and received by the network communication unit 12, and a case where the data requested by the request message is stored in the data storage unit 14. The network communication unit 12 transmits the data to the data display unit 11 and transmits the request message to the cache server device 3 when the data is not stored.
And a user request determination unit 15 for giving an instruction to the user.

The cache server device 3 is a server device such as a content server (not shown) (the server device 1 in FIG. 21).
002) and a network communication unit 31 for communicating with the client device 1, a data storage unit 32 for storing data transmitted from a server device such as a content server to the client device, and reading data stored in the data storage unit 32. And a transmission data determination unit 33 that instructs the network communication unit 31 to distribute this data to the client device 1.

FIG. 3 shows a processing sequence of the communication apparatus according to the present embodiment. The cache server device 3 constantly distributes the data stored therein to the client device 1 (step 101). That is, the transmission data determination unit 33 of the cache server device 3 reads data transmitted from a server device such as a content server (not shown) and stored in the data storage unit 32, and adds a tag indicating the beginning to the beginning of the read data. At the same time, a tag indicating the end is added to the end of the data, and the network communication unit 31 is instructed to distribute the data with the tag added to the client device 1. Network communication unit 31
Sends the data passed from the transmission data determination unit 33 to the network.

When a request message is input from the data display unit 11 (step 102), the user request receiving unit 13 of the client device 1 instructs the network communication unit 12 to receive data distributed from the cache server device 3. Is issued (step 103).
In response to the instruction, the network communication unit 12 receives the data between the start and end tags distributed from the cache server device 3, and stores the data received by the network communication unit 12. To accumulate.

Next, the user request determination section 15 of the client device 1 determines whether or not the data requested by the request message is stored in the data storage section 14 (step 104). If so, the data is transmitted to the data display unit 11, and if not stored, the network communication unit 12 is instructed to transmit the request message to the cache server device 3. In response to this instruction, the network communication unit 12 transmits a request message to the cache server device 3 (Step 105).

Then, the user request determination unit 15
Deletes the data stored in the data storage unit 14 (step 106). The operation after transmitting the request message from the client device 1 to the cache server device 3 is the same as that of the conventional example shown in FIG.

As described above, in the present embodiment, data is constantly delivered from the cache server device 3 to the client device 1, the request message from the client device 1 is terminated by the cache server device 3, and the request message is sent. The client device 1 searches whether data is stored in the own device, and transmits a request message from the client device 1 to the cache server device 3 only when no data is stored in the own device. Therefore, the number of requests sent from the client device 1 can be reduced, and the processing load on the cache server device 3 and the server device 1002 can be distributed.

[Second Embodiment] FIG. 4 is a block diagram showing a configuration of a cache server device in a communication device according to a second embodiment of the present invention. The same components as those in FIG. It is attached. Also in the present embodiment, the overall configuration of the communication device is the same as that of the conventional communication device shown in FIG. In the present embodiment, the transmission data is transmitted in the descending order of the number of requests in the past request history from the client device 1.

The cache server device 3a refers to a network communication unit 31, a data storage unit 32, and a history of request messages stored in a user request storage unit, which will be described later, to store the data stored in the data storage unit 32. A transmission data determination unit 33a that reads the data in the order of requests from the client device 1 in descending order and instructs the network communication unit 31 to distribute the read data to the client device 1, and stores a history of request messages transmitted from the client device 1. And a user request storage unit 34 that performs the operation.

The processing sequence is the same as that of FIG.
When transmitting from the client device 1 to the client device 1, the transmission data determination unit 33 a of the cache server device 3 a refers to the history of the request message stored in the user request storage unit 34 and reads out the data stored in the data storage unit 32. Determines the data to be transmitted. Table 1 shows an example of a history of request messages stored in the user request storage unit 34.

[0033]

[Table 1]

As shown in Table 1, the history of the request message is a URL (Uniform Resource Locator) indicating the file name of the data requested by the request message.
ators) name, a file size indicating the size of data requested by the request message, and a request count indicating the number of times the same data is requested.

The transmission data determination unit 33a reads out the data stored in the data storage unit 32 in order of the number of requests until the data amount becomes transmittable, and adds a tag indicating the beginning to the head of each read data. At the same time, a tag indicating the end is added to the end of each data, and the network communication unit 31 is instructed to distribute each data with the tag added to the client device 1. The network communication unit 31 includes a transmission data determination unit 33
Send the data passed from a to the network.

[Third Embodiment] FIG. 5 is a block diagram showing a configuration of a cache server device in a communication device according to a third embodiment of the present invention. It is attached. Also in the present embodiment, the overall configuration of the communication device is the same as that of the conventional communication device shown in FIG. In the present embodiment, transmission data is transmitted based on a preset transmission data schedule.

The cache server device 3b refers to a network communication unit 31, a data storage unit 32, and a transmission data schedule recorded in a transmission data schedule table, which will be described later, from among the data stored in the data storage unit 32. A transmission data determination unit 33b that determines data to be transmitted and instructs the network communication unit 31 to distribute the determined data to the client device 1, and a transmission data schedule table 35 that stores a data transmission schedule in advance. Have.

The processing sequence is the same as that of FIG.
When transmitting from the client device 1 to the client device 1, the transmission data determination unit 33 b of the cache server device 3 b refers to the transmission data schedule recorded in the transmission data schedule table 35 and selects from the data stored in the data storage unit 32. Determine the data to be sent. Table 2 shows an example of the transmission data schedule recorded in the transmission data schedule table 35.

[0039]

[Table 2]

When the current time has reached the transmission time recorded in the transmission data schedule table 35, the transmission data determination section 33b executes data transmission to the client device 1. That is, the transmission data determination unit 33b extracts the URL name from the record (one horizontal row in Table 2) of the transmission data schedule table 35 in which the transmission time coinciding with the current time is recorded, and stores the data of this URL name in the data. A network communication unit that reads from the unit 32, adds a tag indicating the beginning to the beginning of the read data, adds a tag indicating the end to the end of the data, and distributes the tagged data to the client device 1. Instruct 31. The network communication unit 31 sends out the data passed from the transmission data determination unit 33b to the network.

Thus, in the present embodiment, it is possible to easily access data expected to be accessed from the client device 1 at a specific time. If the amount of data that can be transmitted is not satisfied only by the file whose transmission time is specified, the file is selected and transmitted in descending order of the number of requests, as in the second embodiment.

[Fourth Embodiment] FIG. 6 is a block diagram showing a configuration of a local cache server device in a communication device according to a fourth embodiment of the present invention, and FIG. 7 is a configuration of a center cache server device in this communication device. FIG. Also in the present embodiment, the configuration of the entire communication device is the same as that of the conventional communication device shown in FIG.
In the present embodiment, a case will be described in which data is transmitted in advance from the center cache server device to the local cache server device, and a request message is transmitted from the client device to the local cache server device.

The local cache server device 4 includes a network communication unit 41 for communicating with the client device 1001 and the center cache server device 5, a data storage unit 42 for storing data transmitted from the center cache server device 5, and a client device. When a request message is received from 1001, a user request receiving unit 43 instructs the network communication unit 41 to receive data distributed from the center cache server device 5, and a data storage unit stores the data requested by the request message. 42,
A user request determination instructing the network communication unit 41 to transmit this data to the client device 1001, and instructing the network communication unit 41 to transfer the request message to another cache server device if the data is not stored, A portion 44.

The center cache server device 5 includes a network communication unit 51 for communicating with a server device (server device 1002 in FIG. 25) such as a content server (not shown) or the local cache server device 4, and a client from a server device such as a content server. A data storage unit 52 for storing data transmitted to the device, and a data storage unit 52
And a transmission data determining unit 53 that instructs the network communication unit 51 to read out the data stored in the local cache server device 4 and distribute the data to the local cache server device 4.

FIG. 8 shows a processing sequence of the communication apparatus according to the present embodiment. The center cache server device 5 constantly distributes the data stored therein to the network (step 201). That is, the transmission data determination unit 53 of the center cache server device 5 reads data transmitted from a server device such as a content server (not shown) and stored in the data storage unit 52, and adds a tag indicating the beginning to the beginning of the read data. At the same time, a tag indicating the end is added to the end of the data, and the network communication unit 51 is instructed to transmit the data with the tag added to the network. Network communication unit 5
1 sends the data passed from the transmission data determination unit 53 to the network.

The client device 1001 sends a request message to the network as in the conventional case (step 202). The user request determination unit 44 of the local cache server device 4
When a request message from the client device 1001 is received via the server 1, it is determined whether or not the data requested by the request message is stored in the data storage unit 42 (step 203), and the data is stored. In this case, this data is
1 is instructed to the network communication unit 41 for transmission to the first communication unit. The network communication unit 41 sends out the data passed from the user request determination unit 44 to the network (Step 204).

On the other hand, when the data requested by the request message is not stored in the data storage unit 42, the user request receiving unit 43 sends the network communication unit 41 to receive the data distributed from the center cache server device 5. An instruction is issued (step 205). In response to this instruction, the network communication unit 41 receives the data between the start and end tags distributed from the center cache server device 5, and stores the data in the data storage unit 42.
Accumulates the data received by the network communication unit 41.

After receiving the data from the center cache server device 5, the user request determination unit 44 determines again whether the data requested by the request message is stored in the data storage unit 42 (step 2).
06) If the data is stored, the network communication unit 41 is instructed to transmit the data to the client device 1001 (step 207).

When the data requested by the request message is not stored in the data storage unit 42, the user request determination unit 44 instructs the network communication unit 41 to transmit the request message to the center cache server device 5. Put out. In response to this instruction, the network communication unit 41 transmits a request message to the center cache server device 5 (Step 208).

Then, the user request determination section 44
Deletes the data stored in the data storage unit 42 (step 209). The operation after transmitting the request message from the local cache server device 4 to the center cache server device 5 is the same as that of the conventional example shown in FIG.

[Fifth Embodiment] FIG. 9 is a block diagram showing a configuration of a center cache server device in a communication device according to a fifth embodiment of the present invention. Is attached. Also in the present embodiment, the configuration of the entire communication device is the same as that of the conventional communication device shown in FIG. In the present embodiment, the transmission data is transmitted in the descending order of the number of requests in the past request history from the client device 1.

The center cache server device 5a refers to the network communication unit 51, the data storage unit 52, and the history of request messages stored in the user request storage unit, which will be described later, and refers to the data stored in the data storage unit 52. Network communication unit 51 so that the client device 1001 reads out the requests in descending order of request, and distributes the read data to the local cache server device 4.
And a user request storage unit 54 that stores a history of request messages transmitted from the client device 1.

The processing sequence is the same as that of FIG. 8, but when transmitting data from the center cache server device 5a to the local cache server device 4 in step 201, the transmission data determination section 53a of the center cache server device 5a The data to be transmitted is determined with reference to the request message history stored in the storage unit 54. The contents of the request history are the same as in the second embodiment.

The transmission data determination unit 53a reads out each data stored in the data storage unit 52 until the amount of data that can be transmitted becomes as large as the number of requests, and adds a tag indicating the beginning to the beginning of each read data. At the same time, a tag indicating the end is added to the end of each data, and the network communication unit 51 distributes each data with the tag to the local cache server device 4.
Give instructions to

Sixth Embodiment FIG. 10 shows a sixth embodiment of the present invention.
FIG. 12 is a block diagram showing a configuration of a cache server device in the communication device according to the embodiment, and the same components as those in FIG. 7 are denoted by the same reference numerals. Also in the present embodiment, the configuration of the entire communication device is the same as that of the conventional communication device shown in FIG. In the present embodiment, transmission data is transmitted based on a preset transmission data schedule.

The center cache server device 5b refers to a network communication unit 51, a data storage unit 52, and a transmission data schedule recorded in a transmission data schedule table, which will be described later, to store data in the data storage unit 52. And a transmission data determination unit 53b for instructing the network communication unit 51 to distribute the determined data to the local cache server device 4, and a transmission data schedule table for storing a data transmission schedule in advance. 55.

The processing sequence is the same as that of FIG. 8, but when data is transmitted from the center cache server 5b to the local cache server 4 in step 201, the transmission data determination unit 53b of the center cache server 5b Schedule table 5
The data to be transmitted is determined from the data stored in the data storage unit 52 with reference to the transmission data schedule recorded in the storage unit 5. The contents of the transmission data schedule are the same as in the third embodiment.

The transmission data determination unit 53b calculates a URL from a record (one horizontal row in Table 2) of the transmission data schedule table 55 in which the transmission time coinciding with the current time is recorded.
The data of the URL name is read out from the data storage unit 52, a tag indicating the beginning is added to the head of the read data, and a tag indicating the end is added to the end of the data, and the tag is added. An instruction is issued to the network communication unit 51 to distribute the obtained data to the local cache server device 4. If the amount of data that can be transmitted is not satisfied only with the file whose transmission time is specified, the file is selected and transmitted in descending order of the number of requests, as in the fifth embodiment.

[Seventh Embodiment] FIG. 11 shows a seventh embodiment of the present invention.
12 is a block diagram showing a configuration of a client device in the communication device according to the embodiment of the present invention. FIG. 12 is a block diagram showing a configuration of a cache server device in the communication device. The same components as those in FIGS. Is attached. Also in the present embodiment, the overall configuration of the communication device is the same as that of the conventional communication device shown in FIG. In the present embodiment, wavelength division multiplexing (Wavelength Dependent Multiplexe)
r, hereinafter referred to as WDM), a method in which a client device receives transmission data from a cache server device and acquires a file on a network using a network.

The client device 1c includes the data display unit 1
1, a network communication unit 12c that communicates with the cache server device 3c using the WDM technology, and a method of receiving data distributed from the cache server device 3c when a request message is input from the data display unit 11, which will be described later. A user request accepting unit 13c for issuing an instruction to the receiving wavelength determining unit, a data accumulating unit 14 for temporarily accumulating data distributed from the cache server device 3c and received by the network communication unit 12c, and a request for the request message. When the data is stored in the data storage unit 14, the data is displayed on the data display unit 1.
1, a user request determination unit 15c for instructing the network communication unit 12c to transmit the request message to the cache server device 3c when the request message is not stored, and a reception wavelength specified by the request message. And a reception wavelength determination unit 16 that determines a reception wavelength based on a calculation rule that inputs a name.

The cache server 3c is a server (not shown) such as a content server (server 1002 in FIG. 21) or a client 1
c, a data storage unit 32 for storing data transmitted from a server device such as a content server to a client device, and data stored in the data storage unit 32. A transmission data determination unit 33c for instructing a transmission wavelength determination unit, which will be described later, to distribute the data to the client device 1, a transmission wavelength determination unit 36 for determining a transmission wavelength to be allocated to the transmission data based on a calculation rule using a transmission data name as an input; Having.

FIG. 13 shows a processing sequence of the communication apparatus according to the present embodiment. The cache server device 3c constantly distributes the data stored therein to the client device 1c. That is, the transmission data determination unit 33c of the cache server device 3c reads data transmitted from a server device such as a content server (not shown) and stored in the data storage unit 32, and adds a tag indicating the beginning to the beginning of the read data. At the same time, a tag indicating the end is added to the end of this data, and the transmission wavelength determination unit 36 is instructed to distribute the transmission data with the tag added to the client device 1.

In response to this instruction, the transmission wavelength determining unit 36
The wavelength to be assigned to the transmission data is determined based on a calculation rule using the transmission data name as an input (step 301), and the network communication unit 31c is instructed to distribute the transmission data to the client device 1 at the determined wavelength. The network communication unit 31c converts the data to which the tag has been added by the transmission data determination unit 33c into an optical signal having the wavelength determined by the transmission wavelength determination unit 36, and sends the optical signal to the network (step 302).

When the request message is input from the data display unit 11 (step 303), the user request receiving unit 13c of the client device 1c instructs the reception wavelength determining unit 16 to receive the data distributed from the cache server device 3c. Give instructions.

In response to this instruction, the reception wavelength determining unit 16
The wavelength to be received is determined based on the calculation rule using the data name specified in the request message as an input (step 304), and the network communication unit 12c receives the data distributed from the cache server device 3c at the determined wavelength. (Step 305). The network communication unit 12c receives data between the start and end tags of the wavelength determined by the reception wavelength determination unit 16 from the cache server device 3c, and stores the data in the data storage unit 14c.
Accumulates data received by the network communication unit 12c.

The user request determination section 15c of the client device 1c determines whether or not the data requested by the request message is stored in the data storage section 14 (step 306). Transmits this data to the data display unit 11, and if not stored, instructs the network communication unit 12c to transmit the request message to the cache server device 3c. In response to this instruction, the network communication unit 12c converts the request message into an optical signal having a predetermined wavelength and transmits the optical signal to the cache server device 3c (Step 307).

Then, the user request determination section 15c
Deletes the data stored in the data storage unit 14 (step 308). The operation after transmitting the request message from the client device 1c to the cache server device 3c is the same as that of the conventional example shown in FIG.

Next, a specific example of determining the transmission wavelength and the reception wavelength from the data name will be described. In the present embodiment, by using the same calculation rule (function) for both the transmitting side and the receiving side,
The same wavelength can be selected between the transmitting side and the receiving side without performing communication for wavelength determination. The transmission wavelength determining unit 36 of the cache server device 3c calculates the transmission wavelength λ
i is determined by a function such as the following equation. λi = Digit (MD5 (URL)) mod (number of wavelengths) (1)

MD5 (URL) is a URL indicating a data name
Means to apply a MD-5 hash function to output 128-bit data unique to the input data name,
Digit (MD5 (URL)) means converting MD5 (URL) to a decimal number. mod (number of wavelengths)
Means that Digit (MD5 (URL)) is divided by the number of wavelengths that can be distributed by the communication device of the present embodiment, and the remainder is taken. The transmission wavelength is determined from the remainder. By using the same function, the reception wavelength determining unit 16 of the client device 1c can determine which wavelength should be received from the requested data name.

[Eighth Embodiment] FIG. 14 shows an eighth embodiment of the present invention.
FIG. 13 is a block diagram illustrating a configuration of a cache server device in the communication device according to the embodiment, and the same components as those in FIG. 12 are denoted by the same reference numerals. Also in the present embodiment,
The overall configuration of the communication device is the same as that of the conventional communication device shown in FIG. In the present embodiment, the transmission data is transmitted in the descending order of the number of requests in the past request history from the client device 1.

The cache server device 3d refers to the history of the request message stored in the network communication unit 31c, the data storage unit 32, and the user request storage unit 34, and stores the data stored in the data storage unit 32 in the client. The apparatus includes a transmission data determination unit 33d that reads in the order of requests from the device 1c in descending order and distributes the read data to the client device 1c, a user request storage unit 34, and a transmission wavelength determination unit 36.

The processing sequence is the same as in FIG.
When transmitting data from the cache server device 3d to the client device 1c in step 301, the transmission data determination unit 33d of the cache server device 3d refers to the history of the request message stored in the user request storage unit 34 to store the data. The data to be transmitted is determined from the data stored in the unit 32. The contents of the request history are the same as in the second embodiment.

The transmission data determination unit 33d reads out each data stored in the data storage unit 32 in order of the number of requests until the data amount becomes transmittable, and adds a tag indicating the beginning to the head of each read data. At the same time, a tag indicating the end is added to the end of each data, and the transmission wavelength determining unit 36 is instructed to distribute each data with the tag added to the client device 1c.
Subsequent operations are the same as in the seventh embodiment.

[Ninth Embodiment] FIG. 15 shows a ninth embodiment of the present invention.
FIG. 13 is a block diagram illustrating a configuration of a cache server device in the communication device according to the embodiment, and the same components as those in FIG. 12 are denoted by the same reference numerals. Also in the present embodiment,
The overall configuration of the communication device is the same as that of the conventional communication device shown in FIG. In the present embodiment, transmission data is transmitted based on a preset transmission data schedule.

The cache server device 3 e refers to the network communication unit 31 c, the data storage unit 32, and the transmission data schedule recorded in the transmission data schedule table 35 to transmit data from the data stored in the data storage unit 32. A transmission data determination unit 33e that determines data to be determined and issues an instruction to distribute the determined data to the client device 1c, a transmission data schedule table 35, and a transmission wavelength determination unit 36.

The processing sequence is the same as in FIG.
When transmitting data from the cache server device 3e to the client device 1c in step 301, the transmission data determination unit 33e of the cache server device 3e refers to the transmission data schedule recorded in the transmission data schedule table 35, and The data to be transmitted is determined from the data stored in the P. 32. The contents of the transmission data schedule are the same as in the third embodiment.

The transmission data determination section 33e extracts the URL name from the record of the transmission data schedule table 35 in which the transmission time coincident with the current time is recorded.
The data having the RL name is read from the data storage unit 32, a tag indicating the beginning is added to the beginning of the read data, and a tag indicating the end is added to the end of the data, and the data with the tag is added to the client device 1c. The transmission wavelength determining unit 36 is instructed to distribute the information to the transmission wavelength. Subsequent operations are the same as in the seventh embodiment. If the amount of data that can be transmitted is not satisfied only with the file whose transmission time is specified, the file is selected and transmitted in descending order of the number of requests, as in the eighth embodiment.

[Tenth Embodiment] FIG. 16 is a block diagram showing a configuration of a local cache server device in a communication device according to a tenth embodiment of the present invention. FIG. 17 is a configuration of a center cache server device in this communication device. Is the same as that in FIGS. 6 and 7, and the same reference numerals are given to the same components. Also in the present embodiment, the configuration of the entire communication device is the same as that of the conventional communication device shown in FIG. In the present embodiment, a case will be described in which data is transmitted in advance from the center cache server device to the local cache server device, and a request message is transmitted from the client device to the local cache server device.

The local cache server device 4c
A network communication unit 41c that communicates with the client device 1001 and the center cache server device 5c using the DM technology, a data storage unit 42 that stores data transmitted from the center cache server device 5c, and a request message from the client device 1001. Upon reception, the user request reception unit 43c instructs a reception wavelength determination unit described later to receive data distributed from the center cache server device 5c, and the data requested by the request message is stored in the data storage unit 42. If so, the network communication unit 4 transmits the data to the client device 1001.
1c, and if not stored, a user request determining unit 44c for instructing the network communication unit 41c to transfer the request message to another cache server device, and the reception wavelength is specified by the request message. And a reception wavelength determining unit 46 that determines the received wavelength based on a calculation rule using the input data name.

The center cache server device 5c
A network communication unit 51c that communicates with a server device (not shown) such as a content server (server device 1002 in FIG. 21) or a local cache server device 4c using the DM technology and a server device such as a content server transmitted to a client device. A data storage unit 52 for storing data, and data stored in the data storage unit 52 are read, and the data is stored in the local cache server device 4c.
A transmission data determination unit 53c for instructing a transmission wavelength determination unit, which will be described later, to distribute the transmission data to the transmission data, and a transmission wavelength determination unit 56 for determining a transmission wavelength to be allocated to the transmission data based on a calculation rule using a transmission data name as an input.

FIG. 18 shows a processing sequence of the communication apparatus according to the present embodiment. Center cache server device 5c
Distributes the data stored in its own device to the network at all times. That is, the center cache server device 5
The transmission data determination unit 53c of c reads out data transmitted from a server device such as a content server (not shown) and stored in the data storage unit 52, adds a tag indicating the beginning to the head of the read data, and At the end, a tag indicating the end is added, and the transmission wavelength determination unit 56 is instructed to transmit the data with the tag added to the network.

In response to this instruction, transmission wavelength determining section 56
The wavelength to be allocated to the transmission data is determined based on a calculation rule using the transmission data name as an input (step 401), and the network communication unit 51c is instructed to distribute the transmission data to the client device 1001 at the determined wavelength. The network communication unit 51c converts the data to which the tag has been added by the transmission data determination unit 53c into an optical signal having the wavelength determined by the transmission wavelength determination unit 56, and sends the optical signal to the network (step 402).

The client device 1001 converts the request message into an optical signal of a predetermined wavelength and sends it to the network (step 403). The user request determination unit 44c of the local cache server device 4c
Client device 1 via network communication unit 41c
When the request message from 001 is received, it is determined whether or not the data requested by the request message is stored in the data storage unit 42 (step 4).
04) If the data is stored, the network communication unit 41c is instructed to transmit the data to the client device 1001. Network communication unit 41c
Converts the data passed from the user request determination unit 44c into an optical signal of a predetermined wavelength and sends it to the network (step 405).

On the other hand, when the data requested by the request message is not stored in the data storage unit 42, the user request receiving unit 43c sets the reception wavelength determining unit 46 to receive the data distributed from the center cache server 5c. Give instructions to

In response to this instruction, reception wavelength determining section 46
The network communication unit determines a wavelength to be received based on the calculation rule using the data name specified in the request message as an input (step 406), and receives data distributed from the center cache server device 5c at the determined wavelength. 41c (step 40)
7). The network communication unit 41c includes the reception wavelength determination unit 4
The data between the start and end tags of the wavelength determined in 6 is received from the center cache server device 5c, and the data storage unit 42 stores the data received by the network communication unit 41c.

After receiving the data from the center cache server device 5c, the user request determination unit 44c determines again whether the data requested by the request message is stored in the data storage unit 42 (step 408). If the data is stored, the network communication unit 41c is instructed to transmit the data to the client device 1001 (step 409).

If the data requested by the request message is not stored in the data storage unit 42, the user request determination unit 44c instructs the network communication unit 41c to transmit the request message to the center cache server 5c. Put out. In response to this instruction, the network communication unit 41c converts the request message into an optical signal of a predetermined wavelength and transmits the optical signal to the center cache server device 5c (Step 410).

Then, the user request determination section 44c
Deletes the data stored in the data storage unit 42 (step 411). The operation after transmitting the request message from the local cache server device 4c to the center cache server device 5c is the same as that of the conventional example shown in FIG. The operations of the transmission wavelength determination unit 56 and the reception wavelength determination unit 46 are the same as those of the transmission wavelength determination unit 36 and the reception wavelength determination unit 16 of the seventh embodiment.

[Eleventh Embodiment] FIG. 19 is a block diagram showing a configuration of a center cache server device in a communication device according to an eleventh embodiment of the present invention. Is attached. Also in the present embodiment, the configuration of the entire communication device is the same as that of the conventional communication device shown in FIG. In the present embodiment, the transmission data is transmitted in the descending order of the number of requests in the past request history from the client device 1001.

The center cache server device 5d refers to the history of the request message stored in the network communication unit 51c, the data storage unit 52, and the user request storage unit 54, and stores the data stored in the data storage unit 52. It includes a transmission data determination unit 53d that reads out data in order of request from the client device 1001 and distributes the read data to the local cache server device 4c, a user request storage unit 54, and a transmission wavelength determination unit 56.

The processing sequence is the same as in FIG.
When transmitting data from the center cache server device 5d to the local cache server device 4c in step 401, the transmission data determination unit 53d of the center cache server device 5d uses the user request storage unit 54
Refer to the request message history stored in
Determine the data to be sent. The contents of the request history are the same as in the second embodiment.

The transmission data determination unit 53d reads out each data stored in the data storage unit 52 in the order of the number of requests until the data amount becomes receivable, and adds a tag indicating the beginning to the beginning of each read data. At the same time, a tag indicating the end is added to the end of each data, and the transmission wavelength determination unit 56 is instructed to distribute each data with the tag added to the local cache server device 4c. Subsequent operations are the same as in the tenth embodiment.

[Twelfth Embodiment] FIG. 20 is a block diagram showing a configuration of a cache server device in a communication device according to a twelfth embodiment of the present invention. In FIG. It is attached. Also in the present embodiment, the configuration of the entire communication device is the same as that of the conventional communication device shown in FIG. In the present embodiment, transmission data is transmitted based on a preset transmission data schedule.

The center cache server device 5 e refers to the network communication unit 51 c, the data storage unit 52, and the transmission data schedule recorded in the transmission data schedule table 55, from among the data stored in the data storage unit 52. A transmission data determination unit 53e that determines data to be transmitted and issues an instruction to distribute the determined data to the local cache server device 4c, a transmission data schedule table 55, a transmission wavelength determination unit 56
And

The processing sequence is the same as in FIG.
When transmitting data from the center cache server device 5e to the local cache server device 4c in step 401, the transmission data determination unit 53e of the center cache server device 5e refers to the transmission data schedule recorded in the transmission data schedule table 55. The data to be transmitted is determined from the data stored in the data storage unit 52. The contents of the transmission data schedule are the same as in the third embodiment.

The transmission data determination unit 53e extracts the URL name from the record of the transmission data schedule table 55 in which the transmission time coincident with the current time is recorded, and
The data having the RL name is read from the data storage unit 52, a tag indicating the beginning is added to the beginning of the read data, a tag indicating the end is added to the end of the data, and the data with the tag is added to the local cache server. An instruction is given to the transmission wavelength determining unit 56 to distribute the data to the device 4c. Subsequent operations are the same as in the tenth embodiment. If the amount of data that can be transmitted is not satisfied only with the file whose transmission time is specified, the file is selected and transmitted in order from the file with the largest number of requests, as in the eleventh embodiment.

In the seventh to twelfth embodiments, the data name (URL name) is used as the identification information of the data on which the transmission wavelength and the reception wavelength are based. However, the present invention is not limited to this. Other identification information that can be uniquely identified may be used. Further, the client devices 1, 1c, 1001, and the cache server devices 3, 3a to 3e, 4, 4c, 5, 5a to 5 described in the first to twelfth embodiments.
5e can each be realized by a computer. This computer has a well-known configuration including a central processing unit (CPU), a read-only memory (ROM), a random access memory (RAM), and a circuit for interfacing with a display device, a keyboard, or an external storage device. Is fine.

[0098] The CPU executes processing in accordance with a program stored in the ROM or the RAM, or a command input from the keyboard. Further, the CPU can write data to the external storage device and read data from the external storage device. In such a computer, a program for realizing the communication method of the present invention includes a flexible disk, a CD-ROM,
It is provided in a state recorded on a recording medium such as a VD-ROM and a memory card. When this recording medium is inserted into an external storage device, the program written on the recording medium is read and transferred to a computer. Then, the CPU writes the read program in a RAM or the like. Thus,
The CPU executes the processing described in the first to twelfth embodiments.

[0099]

According to the present invention, in a communication method for mediating communication between a client device and a first server device to be accessed by a cache server device, data is constantly distributed from the cache server device to the client device, The device terminates the request message from the client device, searches the client device to determine whether or not the data requested by the request message is stored in the device itself, and transmits the request message to the client only when the data is not stored. Since the data is transmitted from the device to the cache server device, the number of requests sent from the client device can be reduced, and the processing load of the cache server device and the first server device can be dispersed to realize high-speed processing. can do.

In a communication method in which communication between a client device and a first cache server device is mediated by a second cache server device, the communication method transmitted from the first server device and stored in the first cache server device. Data is constantly distributed from the first cache server device,
The second cache server device terminates the request message from the client device, and the second cache server device searches whether or not the data requested by the request message is stored in its own device, and the data is stored. Only when the request is not sent, the request message is transmitted from the second cache server device to the first cache server device. Therefore, the number of requests sent from the second cache server device can be reduced. By distributing the processing load of the cache server device and the first server device, high-speed processing can be realized.

A communication method for mediating communication using a WDM technique between a client device and a first server device to be accessed by a cache server device,
The transmission wavelength of the transmission data transmitted from the first server device and stored in the cache server device is determined based on the identification information of the transmission data, and the transmission data is constantly distributed from the cache server device to the client device at this transmission wavelength. When a message requesting data is generated from the first server device, the reception wavelength is determined based on the identification information of the data requested in the message, and the data distributed from the cache server device at this reception wavelength is transmitted to the client. By receiving and storing the data in the device, the client device and the cache server device can determine in advance which wavelength carries which data. By receiving and storing only the data of the wavelength, the cache device can be used. Further high-speed processing can be realized.

In a communication method in which communication between a client device and a first cache server device using the WDM technique is mediated by a second cache server device, the first cache device transmits the first cache device to the first cache server device. The transmission wavelength of the transmission data stored in the server device is determined based on the identification information of the transmission data, the transmission data is constantly delivered from the first cache server device at this transmission wavelength, and the reception wavelength is requested by a message. The first cache server is determined based on the identification information of the received data, and the data distributed from the first cache server at this reception wavelength is received and accumulated by the second cache server. The device and the second cache server device can pre-determine which wavelengths carry which data, Only the reception length of the data, it is possible to realize a higher speed caching by accumulating.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a client device in a communication device according to a first embodiment of this invention.

FIG. 2 is a block diagram illustrating a configuration of a cache server device in the communication device according to the first embodiment of this invention.

FIG. 3 is a sequence diagram illustrating processing of the communication device according to the first embodiment of this invention.

FIG. 4 is a block diagram illustrating a configuration of a cache server device in a communication device according to a second embodiment of this invention.

FIG. 5 is a block diagram illustrating a configuration of a cache server device in a communication device according to a third embodiment of the present invention.

FIG. 6 is a block diagram illustrating a configuration of a local cache server device in a communication device according to a fourth embodiment of the present invention.

FIG. 7 is a block diagram illustrating a configuration of a center cache server device in a communication device according to a fourth embodiment of the present invention.

FIG. 8 is a sequence diagram illustrating processing of a communication device according to a fourth embodiment of the present invention.

FIG. 9 is a block diagram illustrating a configuration of a center cache server device in a communication device according to a fifth embodiment of the present invention.

FIG. 10 is a block diagram illustrating a configuration of a cache server device in a communication device according to a sixth embodiment of the present invention.

FIG. 11 is a block diagram illustrating a configuration of a client device in a communication device according to a seventh embodiment of the present invention.

FIG. 12 is a block diagram illustrating a configuration of a cache server device in a communication device according to a seventh embodiment of the present invention.

FIG. 13 is a sequence diagram illustrating processing of a communication device according to a seventh embodiment of the present invention.

FIG. 14 is a block diagram showing a configuration of a cache server device in a communication device according to an eighth embodiment of the present invention.

FIG. 15 is a block diagram illustrating a configuration of a cache server device in a communication device according to a ninth embodiment of the present invention.

FIG. 16 is a block diagram illustrating a configuration of a local cache server device in a communication device according to a tenth embodiment of the present invention.

FIG. 17 is a block diagram illustrating a configuration of a center cache server device in a communication device according to a tenth embodiment of the present invention.

FIG. 18 is a sequence diagram illustrating processing of the communication device according to the tenth embodiment of the present invention.

FIG. 19 is a block diagram illustrating a configuration of a center cache server device in a communication device according to an eleventh embodiment of the present invention.

FIG. 20 is a block diagram illustrating a configuration of a center cache server device in a communication device according to a twelfth embodiment of the present invention.

FIG. 21 shows a client via a cache server.
FIG. 11 is a block diagram illustrating a configuration of a conventional communication device that realizes communication between servers.

FIG. 22 is a sequence diagram showing processing of a conventional communication device.

FIG. 23 is a block diagram illustrating a configuration of a conventional client device.

FIG. 24 is a block diagram showing a configuration of a conventional cache server device.

FIG. 25 is a block diagram showing a configuration of a conventional communication device using a multi-stage cache.

FIG. 26 is a sequence diagram showing processing of a conventional multi-stage cache communication method.

[Explanation of symbols]

1, 1c: client device, 3, 3a to 3e: cache server device, 4, 4c: local cache server device, 5, 5a to 5e: center cache server, 1
1: Data display part, 12, 12c, 31, 31c, 4
1, 41c, 51, 51c: Network communication unit, 1
3, 13c, 43, 43c... User request receiving unit, 14, 32, 42, 52,.
15c, 44, 44c: user request determination unit, 1
6, 46... Reception wavelength determining unit, 33, 33a to 33e, 5
3, 53a to 53e ... transmission data determination unit, 34, 54 ...
User request storage unit, 35, 55 ... transmission data schedule table, 36, 56 ... transmission wavelength determination unit.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Hiroyuki Tanaka 2-3-1 Otemachi, Chiyoda-ku, Tokyo F-term within Nippon Telegraph and Telephone Corporation (reference) 5B082 FA12 HA05 5K030 HA05 HB16 KA01 KA06 LA17 LE03

Claims (24)

[Claims] 1. A communication method for mediating communication between a client device and a first server device to be accessed by a cache server device, wherein data transmitted from the first server device and stored in the cache server device is transmitted. A distribution process of constantly distributing data from the cache server device to the client device, and when a message requesting data from the first server device is generated in the client device, the data distributed from the cache server device is transmitted to the client device. Receiving and accumulating processing for receiving and accumulating at the client device, when the data requested by the message is present in the accumulated data, the data is acquired; otherwise, the message is transmitted to the client device. From the server to the cache server device. A communication method characterized by: 2. A communication method in which communication between a client device and a first cache server device is mediated by a second cache server device, wherein the first cache device is transmitted from a first server device that is an access destination of the client device. A distribution process of constantly distributing data stored in the cache server device from the first cache server device, and storing data requested by a message from the client device in the second cache server device. If this is the case, a reply process of transmitting this data from the second cache server device to the client device; and if the data requested in the message has not been stored, the data distributed from the first cache server device. Receiving and accumulating the received data, and When the data requested by the message exists, the data is transmitted to the client device, and when the data does not exist, a transfer process of transferring the message to the first cache server device is performed. Communication method. 3. A communication method in which communication using a WDM technique between a client device and a first server device to be accessed is mediated by a cache server device, wherein the cache server device transmits from the first server device. A transmission wavelength to be allocated to the transmission data stored in the storage device, based on the identification information of the transmission data, and a distribution process of constantly distributing the transmission data from the cache server device to the client device at the transmission wavelength; When a message requesting data from the first server device occurs in the client device, a reception wavelength is determined based on the identification information of the data requested in the message, and the received wavelength is distributed from the cache server device at the reception wavelength. Receiving and storing processing for receiving and storing the received data in the client device; When the data requested by the message is present in the stored data, the data is acquired, and when the data is not present, the message is transmitted from the client device to the cache server device. A communication method characterized by performing: 4. A communication method for mediating communication using a WDM technique between a client device and a first cache server device by a second cache server device, wherein the first server to be accessed by the client device is provided. A transmission wavelength to be allocated to transmission data transmitted from a device and stored in the first cache server device is determined based on identification information of the transmission data, and the transmission data is transmitted at the transmission wavelength to the first cache server. A distribution process for constantly distributing data from a device, and when data requested by a message from the client device is stored in the second cache server device, the data is transmitted from the second cache server device to the client device. Reply processing to send to the The receiving wavelength is determined based on the identification information of the data requested by the message, and receiving and storing processing for receiving and storing data distributed from the first cache server device at the receiving wavelength; When the data requested by the message exists in the stored data, the data is transmitted to the client device. When the data does not exist, the message is transmitted to the first cache server device. And a processing method. 5. The communication method according to claim 1, wherein the distribution process stores a history of a message transmitted from the client device in the cache server device or the first cache server device. A communication method, comprising: storing and transmitting data stored in the cache server device or the first cache server device in descending order of requests from the client device. 6. The communication method according to claim 1, wherein the distribution processing is performed by transmitting data stored in the cache server device or the first cache server device to transmission data set in advance. A communication method, wherein transmission is performed based on a schedule. 7. A communication device comprising: a client device; a first server device to which the client device accesses; and a cache server device that mediates communication between the client device and the first server device. The cache server device includes means for constantly delivering data transmitted from the first server device and stored in the cache server device to the client device, wherein the client device requests data from the first server device. When a message occurs, receive and accumulate data distributed from the cache server device,
When the data requested by the message exists in the accumulated data, the data is acquired, and when the data does not exist, a means for transmitting the message to the cache server device is provided. Communication device. 8. A client device, a first server device to be accessed by the client device, a first cache server device provided between the client device and the first server device, In a communication device having a first cache server device and a second cache server device provided between the client device, the first cache server device is transmitted from the first server device and stored in its own device. Means for constantly distributing the stored data, wherein the second cache server device receives a message requesting data from the client device,
When the data requested by this message is stored in the own device, the data is transmitted to the client device. When the data is not stored, the data distributed from the first cache server device is transmitted. Receive and accumulate,
When the data requested by the message exists in the stored data, the data is transmitted to the client device. When the data does not exist, the message is transmitted to the first cache server device. A communication device comprising means. 9. A WDM technique comprising: a client device; a first server device to which the client device accesses; and a cache server device that mediates communication between the client device and the first server device. In the communication device that performs communication using, the cache server device determines a transmission wavelength to be allocated to transmission data transmitted from the first server device and stored in the device, based on the identification information of the transmission data. Means for constantly delivering the transmission data to the client device at the transmission wavelength, wherein the client device receives a request for a reception wavelength in the message when a message requesting data to the first server device occurs. Determined based on the identification information of the received data, and distributed from the cache server device at this reception wavelength. Receiving data by accumulating, wherein when the data requested by the message in the stored data exists, if the data to retrieve the absent,
A communication device comprising: means for transmitting the message to the cache server device. 10. A client device, a first server device to be accessed by the client device, a first cache server device provided between the client device and the first server device, A communication device having a first cache server device and a second cache server device provided between the client device and performing communication using the WDM technology, wherein the first cache server device is the first cache server device; Means for determining a transmission wavelength to be allocated to transmission data transmitted from the server device and stored in the own device based on the identification information of the transmission data, and constantly distributing the transmission data at the transmission wavelength, The cache server device receives a message requesting data from the client device,
When the data requested by this message is stored in the own device, the data is transmitted to the client device. When the data is not stored, the reception wavelength is identified by the identification of the data requested by the message. Is determined based on the information, receives and accumulates the data distributed from the first cache server device at this reception wavelength, and when the data requested by the message exists in the accumulated data, A communication device for transmitting the data to the client device, and transferring the message to the first cache server device when the data does not exist. 11. The communication device according to claim 7, 8, 9 or 10, wherein the cache server device or the first cache server device stores a history of a message transmitted from the client device in its own device. A communication device for transmitting data transmitted from the first server device and stored in the own device in descending order of requests from the client device. 12. The communication device according to claim 7, 8, 9, or 10, wherein the cache server device or the first cache server device transmits data transmitted from the first server device and stored in the own device. A communication device for transmitting the data based on a preset transmission data schedule. 13. A network communication unit for communicating with a cache server device provided between a first server device to be accessed and a message requesting the first server device for data. A user request receiving unit that instructs the network communication unit to receive data distributed from the cache server device; a data storage unit that stores data distributed from the cache server device and received by the network communication unit; When the data requested by the message is stored in the data storage unit, the data is acquired. When the data is not stored, the network communication unit is configured to transmit the message to the cache server device. A user request determining unit for instructing. Equipment. 14. A network communication unit that communicates with a cache server device provided between the first server device and an access destination using the WDM technology, and a message that requests data from the first server device. A user request receiving unit that issues an instruction to receive the data distributed from the cache server device when an error occurs, and determines the reception wavelength based on the identification information of the data requested in the message in response to the instruction. A reception wavelength determining unit that instructs the network communication unit to receive data distributed from the cache server device at the reception wavelength; a data storage unit that stores data received by the network communication unit; If the data requested by the message is stored in the data storage unit, obtain this data , If not stored, the client apparatus characterized by having a user request judgment unit to instruct the network communication unit to transmit the message to the cache server apparatus. 15. A cache server device that mediates communication between a client device and a first server device, wherein: a network communication unit that communicates with the first server device or the client device; A data storage unit that stores the data transmitted and received by the network communication unit; and a transmission data determination unit that instructs the network communication unit to distribute the data stored in the data storage unit to the client device. A cache server device characterized by the above-mentioned. 16. A cache server device that mediates communication between a client device and another cache server device, wherein the network communication unit communicates with the other cache server device or the client device; A data storage unit for storing the data, and a message requesting data from the client device, when the data requested by the message is not stored in the data storage unit, an access destination of the client device. A user request receiving unit that instructs the network communication unit to receive, from the other cache server device, data transmitted from the first server device and stored in the other cache server device; Data is stored in the data storage unit If the data is stored, the network communication unit is instructed to transmit the data to the client device, and after receiving the data from the another cache server device, the data requested by the message is stored in the data storage unit. And a user request determination unit that instructs the network communication unit to transfer the message to another cache server device when the message is not stored in the cache server device. 17. A cache server device that mediates communication using WDM technology between a client device and a first server device, wherein the cache server device communicates with the first server device and the client device using WDM technology. A network communication unit; a data storage unit for storing data transmitted from the first server device and received by the network communication unit; and an instruction to distribute transmission data stored in the data storage unit to the client device. And a transmission wavelength determining unit that determines a transmission wavelength to be allocated to the transmission data based on the identification information of the transmission data in accordance with an instruction of the transmission data determination unit, and transmits the transmission data at the transmission wavelength to the client device. And a transmission wavelength determining unit that instructs the network communication unit to distribute to the network communication unit. Cache server device. 18. A cache server device that mediates communication between a client device and another cache server device using WDM technology, wherein the cache server device communicates with the other cache server device or the client device using WDM technology. A network communication unit; a data storage unit for storing data received by the network communication unit; and when receiving a message requesting data from the client device, the data requested by the message is stored in the data storage unit. If not, a user request receiving unit that issues an instruction to receive, from the other cache server device, data transmitted from the first server device to be accessed by the client device and stored in the other cache server device. According to this instruction, the reception wavelength is A receiving wavelength determining unit that determines based on the identification information of the data requested in the message, and instructs the network communication unit to receive data distributed from the other cache server device at the receiving wavelength; and If the requested data is stored in the data storage unit, the network communication unit is instructed to transmit the data to the client device, and after receiving the data from the other cache server device, the message And a user request determination unit that instructs the network communication unit to transfer the message to another cache server device when the data requested in step (a) is not stored in the data storage unit. Cache server device. 19. A client device and a first access destination.
Server program that causes a cache server device that mediates communication with another server device to execute a distribution process of constantly distributing data transmitted from the first server device and stored in the cache server device to the client device Recording medium on which is recorded. 20. Receiving and accumulating data distributed from a cache server device that mediates communication with the first server device when a message requesting data to the first server device to be accessed occurs. A receiving and storing process; and a transferring process of acquiring the data requested by the message in the stored data when the data is present, and transmitting the message to the cache server device when the data is not present. Recording medium storing a client processing program for causing a client device to execute the above. 21. A second cache server device that mediates communication between a client device and a first cache server device, wherein data requested by a message from the client device is stored in the second cache server device. If so, a reply process of transmitting the data to the client device; and if the data requested by the message is not stored, receiving and storing the data distributed from the first cache server device. Receiving and storing processing, when the data requested by the message exists in the stored data, transmitting the data to the client device; otherwise, the message is stored in the first cache. A cache server processing program for executing a transfer process for transferring to a server device. Recording medium. 22. A client device and a first access destination.
A transmission wavelength transmitted from the first server device and allocated to transmission data stored in the cache server device, to the cache server device that mediates communication using the WDM technology with the server device, And a storage medium storing a cache server processing program for executing a distribution process for constantly distributing the transmission data to the client device at the transmission wavelength determined based on the identification information. 23. When a message requesting data is issued to the first server device to be accessed, a reception wavelength is determined based on identification information of the data requested by the message, and the cache server is determined by the reception wavelength. A receiving and storing process of receiving and storing data distributed from the device, and when the data requested by the message exists in the stored data, acquire the data, and when the data does not exist, obtain the data. A recording medium recording a client processing program for causing a client device to execute a transfer process of transmitting the message to the cache server device. 24. A second cache server device that mediates communication using a WDM technique between a client device and a first cache server device, and transmits the data requested by a message from the client device to the second cache server device. A reply process of transmitting the data to the client device when the data is stored in the cache server device; and a receiving wavelength of the data requested by the message when the data requested by the message is not stored. A receiving and storing process of determining based on the identification information and receiving and storing the data distributed from the first cache server device at the receiving wavelength, wherein the data requested by the message is included in the stored data; If present, send this data to the client device; otherwise, send the message And a transfer process for transferring the data to the first cache server device.