JP3208781B2 - Information supply system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information supply system for individually supplying information such as music and moving images to each user terminal in response to requests from a large number of user terminals.

[0002]

2. Description of the Related Art In recent years, a system has been proposed in which information such as music and moving images is distributed and stored in several information centers, and information corresponding to a request from a user terminal is supplied from the information centers. Conventionally, in this type of information supply system, the information group that generates the most frequent requests is stored in the lowest layer information center, the information group with the lowest request frequency is stored in the highest layer information center, and each information center is The user terminals are configured in a tree-shaped multi-layer structure, and are configured so that the possibility of inability to process each information center is averaged to greatly reduce the total information capacity of all information centers.

FIG. 6 is a block diagram showing a conventional information supply system, and FIGS. 7 and 8 are flow charts for explaining the start and stop operations of information supply of the information supply system of FIG. 6, respectively. As shown in FIG. 6, this system includes an upper layer information center 1 of the highest layer, a lower layer information center 2a, 2b of the middle layer as a whole system, and user terminals 3a to 3d of the lowest layer as a whole system. Are configured in a tree-shaped multi-layer. In FIG. 7, when an information reproduction request is issued from the lowest layer, for example, the user terminal 3d to the lower layer information center 2b (step S5).
1) If the requested information does not exist in the lower layer information center 2b (step S2), the lower layer information center 2b
b requests the information to the upper layer information center 1,
The storage of information from the upper layer information center 1 is started (step S3). Then, the reproduction of the stored information is started and supplied to the lowest-level user terminal 3d (step S4),
This reproduction start processing ends (step S5).

As shown in FIG. 8, while the lower layer information center 2b is accumulating information from the upper layer information center 1, the user terminal 3d which has requested the information cancels the request. (Step S6), the lower layer information center 2b stops the information supply (step S7), stops the accumulation of information, and releases the information supply to the upper layer information center 1. By issuing the request (step S8), the limited resources are effectively used. In this case, the lower layer information center 2b generally requests the upper layer information center 1 to cancel the information supply when the user terminal 3d issues the cancellation request.

The lower layer information center 2b, while storing the information from the upper layer information center 1, if another user terminal 3c requests the information, the stored information is transmitted to the user. It is supplied to the terminal 3c.

[0006]

However, in the above-mentioned conventional information supply system, when the lower layer information center 2b issues a cancellation request for information supply to the upper layer information center 1 when one user terminal 3d issues a cancellation request. So do
While the lower layer information center 2b is accumulating information from the upper layer information center 1, if another user terminal 3d issues a release request, the lower layer information center 2b transmits information to the upper layer information center 1. There is a problem in that a supply release request is issued and information supply to the user terminal 3c that has been requested later is stopped.

As shown in FIG. 8, even if one user terminal 3d issues a release request, the lower layer information center 2b
Is configured not to make a request to cancel the information supply to the upper-layer information center 1, the above problem can be solved, but there is a problem that limited resources cannot be used effectively.

Therefore, the present invention can effectively utilize limited resources and can continue to supply information to other lower layers when a release request during information supply from a lower layer occurs. The purpose is to provide an information supply system.

[0009]

According to the present invention, in order to achieve the above object, a lower layer information center receives a request from an upper layer information center when a user terminal requests information that has not been stored. Supply to the terminal, if a release request is received from the user terminal during supply, determine whether the information is being supplied to other user terminals, and if not, issue a release request to the upper information center I do. That is, according to the present invention, a plurality of user terminals arranged in the lowest layer and supplied with information, and an information group in which the frequency of information requests from the user terminals is relatively high are stored. A lower-layer information center that supplies information in response to an information request from the user terminal; and a lower-layer information center that stores information that is not stored in the lower-layer information center in advance when the user terminal requests the lower-layer information center. An upper layer information center that supplies the information to the layer information center and stops the information supply when a release request for stopping the information supply is received from the lower layer information center. When the user terminal requests information that has not been transmitted, the information is received from the upper layer information center and supplied to the user terminal, and a release request is received from the user terminal during the supply. That information if it is determined whether or not supplied to the other user terminals, the information delivery system having a feed release means for issuing a release request when not in supplied to the upper information center is provided.

[0010]

According to the present invention, the lower layer information center receives the information from the upper layer information center and supplies the information to the user terminal when the user terminal requests information that has not been stored. If a release request is received from the user terminal during this, it is determined whether or not the information is being supplied to another user terminal. If the information is being supplied, the release request is not issued to the upper information center. Therefore, limited resources can be effectively used, and when a release request during information supply from a lower layer occurs, information supply to other lower layers can be continued.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the information supply system according to the present invention.

In FIG. 1, the system includes an upper-layer upper-layer information center 10, an intermediate-layer lower-layer information center 20a, 20b as a whole system, and a lower-layer user terminal 30a to 30b as a whole system. 30d is composed of a tree-shaped multi-layer. The upper layer information center 10 stores an information group (information number m) with a relatively low request frequency, and the lower layer information centers 20a and 20b stores an information group with a relatively high request frequency (the information numbers n and k, respectively). ) Is stored.

The lower-layer information centers 20a and 20b are connected to lower user terminals (30a and 30b) and (30
c, 30d), when an information supply request is issued, if the information exists (step S12), the information is supplied. On the other hand, if the information does not exist, a request is made to the upper layer information center 10. While accumulating information from the upper layer information center 10, the lower layer user terminals (30a,
30b) and (30c, 30d).

The upper layer information center 10 is shown by a broken line φ in the figure.
As shown by, the lower-layer information center 20 is connected to the upper-layer center 10 of another system or a higher-level information center.
When a request for information supply from a or 20b occurs, if the information exists, the information is supplied. On the other hand, if the information does not exist, a request is made to the upper layer information center 10 of another system. , While accumulating information from the upper layer information center 10 or the like,
0b can also be supplied.

Each of the information centers 10, 20a, and 20b has at least a counter group 11 (counters 111 to 11p) (p = m +
α), 21a (counters 21a1 to 21aq) (q = n
+ Α), 21b (counters 21b1 to 21br) (r =
k + α). Information centers 10, 20a,
20b respectively correspond to these counters 111 to 11p,
21a1 to 21aq and 21b1 to 21br are reset to the count value “0” at the time of system startup, and each time supply of information from the upper layer to the lower layer is started, the counter of the information is incremented by one. When the supply is completed and released, the counter of the information is decremented by one. Each of the information centers 10, 20a, and 20b continues to supply information when the count value is not "0" when the information supply is canceled by the lower layer, and accumulates information when the count value is "0". And issues an information supply release request to the upper layer information center.

Next, a specific operation of the above embodiment will be described with reference to FIGS. For example, user terminal 30d
Causes a request to reproduce information (step S11), and if the requested information i (i = 1 to r) does not exist in the lower layer information center 20b (step S12), the lower layer information center 20b sends the information i Is the upper layer information center 1
0, and starts accumulating information from the upper layer information center 10 (step S13). Next, the counter 20bi of the information i of the counter groups 20b1 to 20br is set to 1
In step S14, the supply to the lower layer user terminal 30d is started (step S15), and the reproduction start process ends (step S1).
6). In step S12, the user terminal 30d
If the information i (i = 1 to k) requested by the above exists in the lower layer information center 20b, the process jumps to step S14.

Here, when another user terminal 30c requests the information i, the information center 20b supplies the stored information i to the user terminal 30c, and counts one counter 20bi of the information i. Increment.

As shown in FIG. 3, for example, when the user terminal 30d issues a release request for canceling the request for information i (step S21), the information center 20b supplies information to the user terminal 30d. Is canceled (step S22), and the counter 20bi of the information i is decremented by one (step S23).
Then, it is determined whether or not the information i is being accumulated from the upper layer information center 10 (step S24). If the information is not being accumulated, the process is terminated (step S25). It is determined whether the value is “0” (step S26). If the count value is not "0", the process ends (step S27), and the supply of the information i to the other user terminals 30c is continued.

Further, when the user terminal 30c issues a release request for canceling the request for information i (step S21), the information center 20b releases information supply to the user terminal 30d (step S2).
2) In addition, the counter 20bi of the information i is decremented by one (step S23). Then, it is determined whether or not the information i is being accumulated from the upper layer information center 10 (step S
24) If the data is not being accumulated, the process is terminated (step S25). If the data is being accumulated, it is determined whether or not the count value of the information i is “0” (step S26). If the count value is "0", the accumulation of the information i is stopped (step S28), and a release request of the information supply is issued to the upper layer information center 10 (step S29). As described above, when the information i is supplied to the plurality of user terminals 30c and 30d, the information supply release request is issued to the upper layer information center 10 only by the release request of the last user terminal 30c ( Step S29).

Therefore, according to the above embodiment, each of the information centers 10, 20a, and 20b has at least the number of counters 111 to 11 corresponding to the number m, n, and k of its own information.
p, 21a1 to 21aq, 21b1 to 21br,
Each time the supply of information to the lower layer is started, the counter of the information is incremented by one, and when the supply of information is completed and released, the counter of the information is decremented by one, and the count value is “0”. If not, the information supply to the lower layer is continued, so that limited resources can be used effectively. Also, when a release request during the information supply from the lower layer occurs, the information to other lower layers is Supply can be continued.

In the above embodiment, each time the supply of information to the lower layer is started, the counter of the information is incremented by one, and when the supply of the information is completed and when the supply of the information is canceled, the counter of the information is incremented by one. Instead of decrementing, the information may be incremented when the accumulation of information is started, and decremented when the accumulation of information is terminated or stopped. In this case, when each of the information centers 10, 20a and 20b receives a request to cancel the supply of information from the lower layer while accumulating the information supplied from the upper layer information center, it refers to the counter value of the information. When the count value is "1", the storage of the information is stopped, and an information supply release request is issued to the upper layer information center.

As another embodiment, as shown in FIGS. 4 and 5, each information center 10, 2 is replaced with a counter.
0a, 20b are provided with supply information i (i = 1 to p, q, r) and a flag bit group F for indicating the supply destination j (j = 1 to s), and determine whether the information is being supplied or not. The determination may be made. Hereinafter, the second embodiment will be described with reference to FIGS.

First, in FIG. 4, for example, a request for reproducing information is generated by the user terminal 30d (step S3).
1) If the requested information i (i = 1 to r) does not exist in the lower layer information center 20b (step S3)
2), the lower layer information center 20b requests the information i from the upper layer information center 10;
The storage of the information from is started (step S33). Next, the information i and the flag bit corresponding to the user terminal 30d are set (step S34), and supply to the lower layer user terminal 30d (terminal j) is started (step S35). The process ends (step S36). In step S32, the user terminal 3
If the information i requested by 0d exists in the lower layer information center 20b, the process jumps to step S34.

Here, when another user terminal 30c requests the information i, the information center 20b supplies the stored information i to the user terminal 30c, and sends the information i and the user terminal 30c to the user terminal 30c. Set the corresponding flag.

Then, as shown in FIG. 5, for example, when the user terminal 30d issues a release request for canceling the request for information i (step S41), the information center 20b supplies information to the user terminal 30d. Is canceled (step S42), and the flag corresponding to the information i and the user terminal 30d is reset (step S43). Then, it is determined whether or not the information i is being accumulated from the upper layer information center 10 (step S44). If the information i is not being accumulated, an information supply release request is issued to the upper layer information center 10 and the process is terminated. Then (step S47), when the data is being accumulated, it is determined whether or not all the flags of the information i are “0” (step S45). If the flags are all “0”, the accumulation of the information i is stopped, and the upper layer information center 10
Issue a request to cancel the information supply (step S4).
6) This process ends (step S47). On the other hand, if all the flags are not "0", the process is terminated as it is (step S47), so that the information supply to the other user terminals 30c is continued.

Therefore, similarly, in this embodiment, limited resources can be effectively used.
When a release request during supply of information from a lower layer occurs, information supply to another lower layer can be continued.

[0027]

As described above, according to the present invention, the lower-layer information center receives the information from the upper-layer information center when the user terminal requests information that has not been stored, and sends the information to the user terminal. Supply, when receiving a release request from a user terminal during supply, determine whether the information is being supplied to another user terminal, and do not issue a release request to the upper layer information center when supplying . Therefore, limited resources can be effectively used, and when a release request during information supply from a lower layer occurs, information supply to other lower layers can be continued.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of an information supply system according to the present invention.

FIG. 2 is a flowchart for explaining an operation of starting supply of information by a lower layer information center of FIG. 1;

FIG. 3 is a flowchart for explaining an operation of stopping the information supply of the lower layer information center of FIG. 1;

FIG. 4 is a flowchart for explaining an operation of starting information supply of a lower layer information center in the second embodiment of the information supply system according to the present invention.

FIG. 5 is a flowchart for explaining the operation of stopping the information supply of the lower layer information center in the second embodiment of the information supply system according to the present invention.

FIG. 6 is a block diagram showing a conventional information supply system.

7 is a flowchart for explaining an operation of starting supply of information by the lower layer information center of FIG. 6;

8 is a flowchart illustrating an operation of stopping the information supply of the lower layer information center in FIG. 6;

[Explanation of symbols]

10 Upper layer information center 20a, 20b Lower layer information center 30a-30d User terminal 11, 21a, 21b Counter group 111-11p, 21a1-21aq, 21b1-21
br, 21bi counter F flag bit group

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04L 29/08 G06F 13/00 G06F 12/00 G06F 15/00

Claims (1)

(57) [Claims] 1. A plurality of user terminals arranged in the lowest layer and supplied with information, and an information group having a relatively high frequency of information requests from the user terminals are stored. A lower-layer information center supplied by an information request from the user terminal; and, if the user terminal requests information not stored in the lower-layer information center from the lower-layer information center, the lower-layer information center supplies the information. And an upper layer information center that stops the information supply when a release request for stopping the information supply is received from the lower layer information center, and the lower layer information center is not stored. When the information is requested by the user terminal, the information is received from the upper layer information center and supplied to the user terminal. An information supply system comprising: a supply canceling unit that determines whether information is being supplied to another user terminal or not, and issues a release request to the upper information center when the information is not being supplied.