Abstract:
A server transmits distribution communication blocks to a relay client and other clients through the Internet. The communication blocks include at least addresses and pieces of distribution information of the relay client and the other clients. The relay client obtains the pieces of distribution information from the distribution communication blocks, and circulates the communication blocks in which distribution results are set to a client next in the order on the basis of the addresses. The last client that receives the distribution communication block transmits it to the relay client. The relay client relays the distribution communication block back to the server.

Description:
FIELD OF THE INVENTION 
   The present invention relates to an information collection and distribution system for collecting and distributing information between computers which are connected to each other through a network. 
   BACKGROUND OF THE INVENTION 
   In recent years, with rapid spread of an advanced communication infrastructure represented by the Internet, collection and distribution of information between computers (e.g., between a server and a client) are generally performed according to a communication protocol such as the HTTP (Hypertext Transfer Protocol), the IIOP (Internet Inter ORB Protocol) or the FTP (File Transfer Protocol). However, recently, the following problems have arisen. 
   (1) In information collection and distribution through the Internet, illegal acts such as falsification, wiretapping, and pretending may be performed. For this reason, an operation load on a system manager for ensuring security tends to increases. 
   (2) With an increase in the number of accesses with an increase of the number of users, or an increase in the quantity of information (image data, audio data, computer program, and the like) to be collected and distributed, a load on a network increases. 
   (3) With an increase in the number of client device, a load on a server for controlling collection and distribution of information increases. 
   Accordingly, means and method for effectively solving the above-mentioned problems is in demand. 
     FIG. 22  is a block diagram showing an example of configuration of a conventional information collection and distribution system. In this diagram, a client/server type information collection and distribution system which is structured through a network having a LAN (Local Area Network)—WAN (Wide Area Network)—LAN form is shown. A main office network system  10  is an in-house system, and is constituted by a main office server  11 , a LAN  13 , and a fire wall  14 . 
   The main office server  11  comprises a function of distributing information (e.g., an application program  12 ) to an employee  0  client  33   0  to an employee n client  33   n  (to be described later) and a function of collecting information from the employee  0  client  33   0  and the employee n client  33   n . The main office server  11  is connected to the LAN  13 . The fire wall  14  is used to prevent illegal access to the main office network system  10  from an external system, and is designed to pass only information or a protocol to which a security is given. The LAN  13  is an in-house network installed in the main office, and is connected to the Internet  20  through the fire wall  14 . 
   A branch office network system  30  is an in-house system structured in a branch office, and is constituted by a fire wall  31 , a LAN  32 , and an employee  0  client  33   0  to an employee n client  33   n . The fire wall  31  is used to prevent illegal access to the branch office network system  30 . The LAN  32  is an in-house network installed in the branch office, and is connected to the Internet  20  through the fire wall  31 . The employee  0  client  33   0  to the employee n client  33   n  are computers which are arranged for an employee  0  to an employee n (not shown) in the branch office, respectively, and are connected to the LAN  32 . 
   Operation of the information collection and distribution system shown in  FIG. 22  will be described below with reference to a sequence chart shown in FIG.  23 . In step F 1  in  FIG. 23 , the main office server  11  transmits an application program  12  as a communication block to the employee  0  client  33   0  through the LAN  13 , the fire wall  14 , the Internet  20 , the fire wall  31 , and the LAN  32  (to be referred to as a network hereinafter) to distribute the application program  12  as information to the employee  0  client  33   0  to the employee n client  33   n  by a circulation system. 
   When the communication block (application program  12 ) is received, in step F 2 , the employee  0  client  33   0  stores a copy of the application program  12  in a storage device (not shown), and then notifies the main office server  11  of a progress status of distribution through the network. Here, the status is that the communication block is received, i.e., that the communication block is circulated to the employee  1  client  33   1  which is a circulation destination. 
   In step F 3 , the employee  0  client  33   0  transmits (circulates) a communication block to the employee  1  client  33   1  which is the next circulation destination through the LAN  32 . When the communication block is received, in step F 4 , the employee  1  client  33   1  stores a copy of the application program  12  in the storage device, and then notifies the main office server  11  of a progress status of distribution through the network. 
   In step F 5 , the employee  1  client  33   1  transmits (circulates) the communication block to the employee  2  client  33   2  which is a circulation destination through the LAN  32 . Thereafter, the clients subsequent to the employee  2  client  33   2  notify the main office server  11  of statuses, and sequentially transmit communication blocks to clients which are next circulation destinations. 
   When a communication block is transmitted to the employee n client  33   n  which is the final circulation destination, the employee n client  33   n , the employee n client  33   n  stores a copy of the application program  12  in the storage device, and then notifies the main office server  11  of a progress status of distribution through the network. 
   In this manner, in the conventional information collection and distribution system, a communication program is transmitted to the employee  0  client  33   0  which represents the employee  0  client  33   0  and the employee n client  33   n , and communication blocks are sequentially circulated to the employee  0  client  33   0 →the employee  1  client  33   1 → . . . → the employee n client  33   n  in the branch office network system  30 , so that information distribution is realized. 
   On the other hand, in the conventional information collection and distribution system, status notifications are performed from the employee  0  client  33   0  to the employee n client  33   n , respectively, so that collection of pieces of information is realized on the main office server  11  side. 
     FIG. 24  is a block diagram showing another example of the configuration of a conventional information collection and distribution system. The same reference numerals as in  FIG. 22  denote the same parts in FIG.  24 . In  FIG. 24 , a dedicated server  40  for controlling collection and distribution on the branch office network system  30  side is newly connected to the LAN  32 . 
   Operation of the information collection and distribution shown in  FIG. 24  will be described below with reference to the sequence diagram shown in FIG.  25 . In step G 1  shown in  FIG. 25 , the main office server  11  transmits the application program  12  to the dedicated server  40  through the Internet  20  to distribute the application program  12  as information to the employee  0  client  33   0  to the employee n client  33   n  by a circulation system. 
   When the application program  12  is received, in step G 2 , the dedicated server  40  transmits (circulates) the application program  12  to the employee  0  client  33   0  which is the first circulation destination through the LAN  32 . When the application program  12  is received, in step G 3 , the employee  0  client  33   0  stores a copy of the application program  12  in the storage device, and then notifies the dedicated server  40  of a progress status of distribution through the LAN  32 . Here, the status is that the application program  12  is distributed. 
   In step G 4 , the dedicated server  40  transmits the application program  12  to the employee  1  client  33   1  which is the next circulation destination through the LAN  32 . When the application program  12  is received, in step G 5 , the employee  1  client  33   1  stores a copy of the application program  12  in the storage device, and then notifies the dedicated server  40  of a progress status of distribution through the LAN  32 . Thereafter, transmission of the application program  12  from the dedicated server  40  to the client which is a circulation destination and status notification from the client to the dedicated server  40  are sequentially performed. 
   When the application program  12  is transmitted to the employee n client  33   n  which is the final circulation destination in step G 6 , in step G 7 , the employee n client  33   n  stores a copy of the application program  12  in the storage device, and then notifies the dedicated server  40  of a progress status of distribution through the LAN  32 . 
   In this manner, when distribution (circulation) to the employee  0  client  33   0  to the employee n client  33   n  is completed, in step G 8 , the dedicated server  40  notifies the main office server  11  of an entire status obtained by collecting status notifications which are respectively received from the employee  0  client  33   0  to the employee n client  33   n  through the network. 
   Techniques related to the information collection and distribution by the circulation system are disclosed in Japanese Unexamined Patent Publication No. 9-8801, Japanese Examined Patent Publication No. 2740105, Japanese Unexamined Patent Publication No. 6-216934 and Japanese Unexamined Patent Publication No. 11-25185, respectively. 
   However, in the information collection and distribution system shown in  FIG. 22 , the status notifications are respectively performed from the employee  0  client  33   0  to the employee n client  33   n  to the main office server  11 . For this reason, an amount of traffic on the network increases in proportion to the number of clients. Accordingly, the network and the main office server  11  disadvantageously receive a heavy load. 
   In addition, the information collection and distribution system shown in  FIG. 22  is designed such that status notifications are respectively performed from the employee  0  client  33   0  to the employee n client  33   n . For this reason, it is not preferable that traffic passes through the fire wall  31  every status notification. Therefore, a load on a system manager for securing a security disadvantageously increases. 
   On the other hand, in the information collection and distribution system shown in  FIG. 24 , the dedicated server  40  is arranged to perform status notifications to the main office server  11  at once. For this reason, load on the Internet  20  and the LAN  13  are reduced, and the information collection and distribution system is more secured as compared to the information collection and distribution system shown in FIG.  22 . 
   However, in the information collection and distribution system shown in  FIG. 24 , status notifications are still performed from the employee  0  client  33   0  to the employee n client  33   n  to the dedicated server  40 , respectively. For this reason, a heavy load disadvantageously acts on the LAN  32 . In the information collection and distribution system shown in  FIG. 24 , the dedicated server  40  must be arranged independently of the employee  0  client  33   0  to the employee n client  33   n , so that the costs disadvantageously increase. 
   In addition, in the information collection and distribution systems shown in FIG.  22  and  FIG. 24 , the circulation system is employed between the employee  0  client  33   0  to the employee n client  33   n . For this reason, a long period of time is disadvantageously required to end all the collection and distribution. 
   SUMMARY OF THE INVENTION 
   It is an object of this invention to provide an information collection and distribution system which can reduce load on the network cheaply, which has high security, and which can shorten a period of time required for collection and distribution. 
   In the information collection and distribution system according to the present invention, the server transmits communication blocks including at least addresses and pieces of distribution information of the plurality of clients to one client of the plurality of clients through the network. One client (the first client) obtains the pieces of distribution information from the communication blocks, and circulates the communication blocks in which distribution results are set to the next client on the basis of the addresses (thus, the information is distributed to clients one after the other). A final client (a client that has received the information last) transmits the communication block to the first client. The first client relays the communication block transmitted from the final client of the circulation destination to the server. 
   Thus, when a communication block is transmitted from the server to the first client, the first client obtains a piece of distribution information from the communication block, sets the distribution result in the communication block, and circulates the communication block to a client of the next circulation destination. Thereafter, communication blocks are sequentially circulated from clients to clients. In this manner, the respective clients obtain pieces of distribution information from communication blocks, and set distribution results in the communication blocks. A communication block from the final client of the circulation destination is relayed to the server through one client. 
   Thus, the first client performs the relay of information. When circulation of all communication blocks is completed, a communication block in which a distribution result is set is relayed to a server through the first client. For this reason, unlike the conventional technique, a dedicated server need not be arranged, and only a communication block may transmitted from an in-house network to an external network once. Therefore, a network load can be reduced cheaply and a high security can be maintained. 
   Other objects and features of this invention will become apparent from the following description with reference to the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a block diagram showing the configuration of a first embodiment according to the present invention. 
       FIG. 2  is a diagram showing the data structure of a basic communication block  700  used in the first embodiment. 
       FIG. 3  is a diagram showing the data structure of a distribution communication block  800  used in the first embodiment. 
       FIG. 4  is a diagram showing the data structure of a collection communication block  900  used in the first embodiment. 
       FIG. 5  is a flow chart for explaining an operation of a communication block forming unit  150  shown in FIG.  1 . 
       FIG. 6  is a flow chart for explaining an operation of a collection and distribution controller  130  shown in FIG.  1 . 
       FIG. 7  is a flow chart for explaining an operation of a result management unit  190  shown in FIG.  1 . 
       FIG. 8  is a flow chart for explaining operations of collection and distribution controllers  420  and  620  shown in FIG.  1 . 
       FIG. 9  is a flow chart for explaining operations of circulation controllers  450  and  650  shown in FIG.  1 . 
       FIG. 10  is a sequence diagram for explaining a distribution operation in Operational Example 1 of the first embodiment. 
       FIG. 11  is a sequence diagram for explaining a distribution operation in Operational Example 1 of the first embodiment. 
       FIG. 12  is a sequence diagram for explaining a retry distribution operation in Operational Example 1 of the first embodiment. 
       FIG. 13  is a flow chart for explaining an operation of a circulation controller in Operational Example 2 of the first embodiment. 
       FIG. 14  is a sequence diagram for explaining a distribution operation in Operational Example 2 of the first embodiment. 
       FIG. 15  is a block diagram for explaining Operational Example 3 of the first embodiment. 
       FIG. 16  is a flow chart for explaining an operation of a circulation controller  450  shown in FIG.  1 . 
       FIG. 17  is a flow chart for explaining an operation of a partition processor  490  shown in FIG.  1 . 
       FIG. 18A  to  FIG. 18D  are diagrams showing the data structures of partitioned distribution communication blocks  800   1  to  800   x  used in Operational Example 3 of the first embodiment. 
       FIG. 19  is a sequence diagram for explaining a partitioned distribution operation in Operational Example 3 of the first embodiment. 
       FIG. 20  is a block diagram showing the configuration of a second embodiment according to the present invention. 
       FIG. 21  is a diagram showing state transitions of a distribution communication block  1300  used in the second embodiment. 
       FIG. 22  is a block diagram showing an example of configuration of a conventional information collection and distribution system. 
       FIG. 23  is a sequence diagram for explaining an operation of the information collection and distribution system shown in FIG.  22 . 
       FIG. 24  is a block diagram showing an another example of configuration of a conventional information collection and distribution system. 
       FIG. 25  is a sequence diagram for explaining an operation of the information collection and distribution system shown in FIG.  24 . 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Two preferred embodiments of an information collection and distribution system according to the present invention will be described below with reference to the accompanying drawings. 
     FIG. 1  is a block diagram showing the configuration of a first embodiment according to the present invention. In  FIG. 1 , a client/server type information collection and distribution system constructed through the Internet  200  is shown. A server  100  comprises a function of distributing pieces of information to client groups  300   1  to 300 m  and a function of collecting pieces of information from the client groups  300   1  to 300 m . As the pieces of information which are mentioned here, various data, various files, computer programs, and the like are used. The server  100  is connected to the Internet  200  through the fire wall to prevent illegal access from an external system. 
   The client group  300   1  is constituted by n+1 clients, i.e., a relay client  400  and clients  600   1  to 600 n . Unique addresses are given to the relay client  400  and the clients  600   1  to  600   n , respectively. Each of the client groups  300   2  to 300 m  is also, constituted by a plurality of clients (including a relay client) like the client group  300   1 . 
   In the server  100 , an operation unit  110  is a keyboard, a mouse, or the like for inputting information required to operate collection and distribution and to output the results of collection and distribution. A display unit  120  is an LCD (Liquid Crystal Display) or a CRT (Cathode-Ray Tube) for displaying various pieces of information used in collection and distribution. A collection and distribution controller  130  performs collection and distribution control. An operation of the collection and distribution controller  130  will be described below with reference to a flow chart. 
   A data storage unit  140  stores information to be distributed, collected information, and a communication block (to be described later). A communication block forming unit  150  forms a communication block used in collection and distribution to store the communication block in the data storage unit  140 . As communication blocks mentioned here, a basic communication block  700  (see FIG.  2 ), a distribution communication block  800  (see FIG.  3 ), and a collection communication block  900  (see  FIG. 4 ) are used. As the descriptive forms of the basic communication block  700 , the distribution communication block  800 , and the collection communication block  900 , a binary form, a text form, an XML (extensible Markup Language) form which rapidly spreads in recent years, and the like are used. 
   The basic communication block  700  shown in  FIG. 2  is constituted by a start header  710 , a collection and distribution ID  720 , a circulation information region header  730 , a circulation information region  740 , a distribution information header  750 , a distribution information region  760 , a collection information header  770 , and a collection information region  780  to perform collection and distribution in units of client groups each constituted by m clients. 
   The start header  710  is a header indicating a start position (leading position) of the basic communication block  700 . The collection and distribution ID  720  is an identifier for uniquely identifying a communication job (collection or distribution). Therefore, the collection and distribution ID  720  is given to each communication job. The circulation information region header  730  is a header indicating a start position of the circulation information region  740 . In the circulation information region  740 , pieces of information related to circulation such as the client name of a circulation destination, an address, and the like are set. 
   More specifically, in the circulation information region  740 , (n+1) pairs of pieces of information, i.e., a circulation destination information header  741   0  and a circulation destination information  742   0  (one pair), a circulation destination header  741   1  and a circulation destination information  742   1  (one pair), . . . , and a circulation destination information header  741   n  and a circulation destination information  742   n  (one pair) are set. These (n+1) pairs of pieces of information correspond to the (n+1) clients, e.g., the relay client  400  (upper level client) and the clients  600   1  to  600   n  (lower level clients) in the client group  300   1  shown in  FIG. 1 , respectively. 
   The circulation destination information headers  741   0  to  741   n  are headers indicating the start positions of the pieces of circulation destination information  742   0  to  742   n , respectively. The pieces of circulation destination information  742   0  to  742   n  are constituted by information related to a destination (client) of circulation and information for management. More specifically, the circulation destination information  742   0  is constituted by a client name  743   0  an address  744   0 , a collection and distribution management information region header  745   0 , a collection and distribution management flag  746   0 , a result management information  747   0 , and a result management information region  748   0 . The client name  743   0  is the name of a circulation destination (in this case, the relay client  400 ). The address  744   0  is the address of the circulation destination (in this case, the relay client  400 ). 
   The collection and distribution management information region header  745   0  is a flag indicating the start position of the collection and distribution management flag  746   0 . The collection and distribution management flag  746   0  is a flag for managing a collection and distribution status, i.e., “collected”, “uncollected”, “distributed”, or “undistributed”. In this case, when the collection and distribution management flag  746   0  is “collected” (or “distributed”), it means that information related to the relay client  400  is collected (distributed). On the other hand, when the collection and distribution management flag  746   0  is “uncollected” (or “undistributed”), it means that information related to the relay client  400  is not collected (distributed). 
   The result management information  747   0  is a flag indicating the start position of the result management information region  748   0 . The result management information region  748   0  indicates the result of collection and distribution, i.e., “normal”, “abnormal”, “undefined”. In this case, when the result management information region  748   0  is “normal”, it means that the collection and distribution related to the relay client  400  is normally performed. When the result management information region  748   0  is “abnormal”, it means that the collection and distribution related to the relay client  400  cannot be performed due to defect or the like. When the result management information region  748   0  is “undefined”, it means that the collection and distribution related to the relay client  400  have not been performed. 
   The circulation destination information  742   1  has the same data structure as that of the circulation destination information  742   0  described above, and is constituted by a client name  743   1 , an address  744   1 , a collection and distribution management information region header  745   1 , a collection and distribution management flag  746   1 , a result management information  747   1 , and a result management information region  748   1 . The client name  743   1  is the name of a circulation destination (in this case, the client  600   1 ). The address  744   1  is the address of the circulation destination (in this case, the client  600   1 ). 
   The collection and distribution management information region header  748   1 , is a flag indicating the start position of the collection and distribution management flag  746   1 . The collection and distribution management flag  746   1  is a flag for managing a collection and distribution status, i.e., “collected”, “uncollected”, “distributed”, or “undistributed”. In this case, when the collection and distribution management flag  746   1  is “collected” (or “distributed”), it means that information related to the client  600   1  is collected (distributed). On the other hand, when the collection and distribution management flag  746   1  is “uncollected” (or “undistributed”), it means that information related to the client  600   1  is not collected (distributed). 
   The result management information  747   1  is a flag indicating the start position of the result management information region  748   1 . The result management information region  748   1  indicates the result of collection and distribution, i.e., “normal”, “abnormal”, “undefined”. In this case, when the result management information region  748   1  is “normal”, it means that the collection and distribution related to the client  600   1  are normally performed. When the result management information region  748   1  is “abnormal”, it means that the collection and distribution related to the client  600   1  cannot be performed due to defect or the like. 
   When the result management information region  748   1  is “undefined”, it means that collection and distribution related to the client  600   1  have not been performed. Subsequently, by the same manner as described above, the circulation destination information  742   n  has the same data structure as those of the circulation destination information  742   0  and the circulation destination information  742   1 , and is information corresponding to the client  600   n . 
   The distribution information header  750  is a header indicating the start position of the distribution information region  760 . In the distribution information region  760 , information to be distributed (computer program or the like) is set. The collection information header  770  is a header indicating the start position of the collection information region  780 . In the collection information region  780 , information related to collection is set. More specifically, in the collection information region  780 , (n+1) sets of pieces of information, i.e., a client name  781   0 , an address  782   0 , collection information  783   0  (one set), a client name  781   1 , an address  782   1 , collection information  783   1  (one set), . . . , and a client name  781   n , an address  782   n , collection information  783   n  (one set). 
   These (n+1) sets of pieces of information correspond to the (n+1) clients, e.g. the relay client  400  and the clients  600   1  to 600 n  in the client group  300   1  shown in  FIG. 1 , respectively. 
   The client name  781   0  is the name of a client (in this case, the relay client  400 ) to which the collection information  783   0  is to be provided. The address  782   0  is an address given to the relay client  400 . The collection information  783   0  is information collected in the server  100 , and is information provided from the relay client  400 . 
   The client name  781   1  is the name of a client (in this case, the client  600   1 ) to which the collection information  783   1  is to be provided. The address  782   1  is an address given to the client  600   1 . The collection information  783   1  is information collected in the server  100 , and is information provided from the client  600   1 . 
   Subsequently, similarly, the client name  781   n  is the name of a client (in this case, the client  600   n ) to which the collection information  783   n  is to be provided. The address  782   n  is an address given to the client  600   n . The collection information  783   n  is information collected in the server  100 , and is information provided from the client  600   n . 
   The distribution communication block  800  shown in  FIG. 3  is obtained by extracting information required for distribution from the basic communication block  700  shown in  FIG. 2 , and is constituted by pieces of information except for the collection information header  770  and the collection information region  780  (see FIG.  2 ). The same reference numerals as in  FIG. 2  denote the same parts in FIG.  3 . The distribution communication block  800  is used when information is distributed to the client group  300   1  shown in FIG.  1 . When pieces of information are distributed to the client groups  300   2  to 300 m , a plurality of distribution communication blocks each having the same data structure as that of the distribution communication block  800  are also formed. 
   The collection communication block  900  shown in  FIG. 4  is obtained by extracting information required for collection from the basic communication block  700  shown in  FIG. 2 , and is constituted by pieces of information except for the distribution information header  750  and the distribution information region  760  (see FIG.  2 ). The same reference numerals as in  FIG. 2  denote the same parts in FIG.  4 . The collection communication block  900  is used when information is collected from the client group  300   1  shown in FIG.  1 . When pieces of information are collected from the client groups  300   2  to 300 m , a plurality of collection communication blocks each having the same data structure as that of the collection communication block  900  are also formed. 
   Referring again to  FIG. 1 , a data processor  160  of the server  100  executes data processing to the distribution communication block  800  and the basic communication block  700 . A transmission processor  170  transmits the distribution communication block  800  or the collection communication block  900  to, e.g., the relay client  400  of the client group  300   1  through the Internet  200 . A reception processor  180  receives the distribution communication block  800  or the collection communication block  900  through the internet  200 . A result management unit  190  manages the results of collection and distribution. 
   In the client group  300   1 , the relay client  400  and the clients  600   1  to 600 n  are (n+1) computers, and circulate the distribution communication block  800  or the collection communication block  900  by a circulation system to realize distribution or collection. In this case, the relay client  400  also comprises, in addition to the functions of the clients  600   1  to 600 n , a relaying function which relays the distribution communication block  800  or the collection communication block  900  between the server  100  and the clients  600   1  to 600 n . The relay client  400  and the clients  600   1  to 600 n  are connected to each other through a LAN  500 . In fact, the LAN  500  is connected to the Internet  200  through the fire wall. 
   In the relay client  400 , a reception processor  410  receives the distribution communication block  800  or the collection communication block  900  from the server  100  through the Internet  200 . A collection and distribution controller  420  is to perform collection and distribution control. The details of an operation of the collection and distribution controller  420  will be described later with reference to a flow chart. A data processor  430  performs data processing to the distribution communication block  800  or the collection communication block  900 . A data storage unit  440  stores distribution information or other data distributed from the server  100 . 
   A circulation controller  450  performs circulation control using the distribution communication block  800  or the collection communication block  900 . A transmission processor  460  transmits the distribution communication block  800  or the collection communication block  900  to the client  600   1  through the LAN  500 . A reception processor  470  receives the distribution communication block  800  or the collection communication block  900  through the LAN  500 . 
   A transmission processor  480  transmits the distribution communication block  800  or the collection communication block  900  to the server  100  through the Internet  200 . A partition processor  490  executes processing when the clients  600   1  to  600   n  into a plurality of groups as will be described later in Operational. Example 3. The details of an operation of the partition processor  490  will be described later. 
   In the client  600   1 , a reception processor  610  receives the distribution communication block  800  or the collection communication block  900  from the relay client  400  through the LAN  500 . A collection and distribution controller  620  is to perform collection and distribution control. The details of an operation of the collection and distribution controller  620  will be described later with reference to a flow chart. A data processor  630  performs data processing to the distribution communication block  800  or the collection communication block  900 . A data storage unit  640  stores distribution information or other data distributed from the server  100 . 
   A circulation controller  650  performs circulation control using the distribution communication block  800  or the collection communication block  900 . A transmission processor  660  transmits the distribution communication block  800  or the collection communication block  900  to the client  600   2  through the LAN  500 . A reception processor  670  receives the distribution communication block  800  or the collection communication block  900  through the LAN  500 . 
   A transmission processor  680  transmits the distribution communication block  800  or the collection communication block  900  to the relay client  400  through the LAN  500 . A partition processor  690  executes processing when the clients  600   1  to  600   n  into a plurality of groups as will be described later in Operational Example 3. The details of an operation of the partition processor  690  will be described later. 
   Operational Example 1 of the first embodiment will be described below with reference to flow charts respectively shown in  FIG. 5  to FIG.  9  and sequence diagrams respectively shown in  FIG. 10  to FIG.  12 .  FIG. 5  is a flow chart for explaining an operation of the communication block forming unit  150  in the server  100  shown in  FIG. 1 , and  FIG. 6  is a flow chart for explaining an operation of the collection and distribution controller  130  in the server  100  shown in FIG.  1 . 
     FIG. 7  is a flow chart for explaining an operation of the result management unit  190  in the server  100  shown in  FIG. 1 , and  FIG. 8  is a flow chart for explaining operations of the collection and distribution controllers  420  and  620  in the relay client  400  and the client  600   1  shown in FIG.  1 .  FIG. 9  is a flow chart for explaining an operation of the circulation controller  450  or  650  shown in FIG.  1 .  FIG. 10  is a sequence diagram for explaining a distribution operation in Operational Example 1 of the first embodiment.  FIG. 11  is a sequence diagram for explaining a distribution operation in Operational Example 1 of the first embodiment.  FIG. 12  is a sequence diagram for explaining a retry distribution operation in Operational Example 1. 
   First, a distribution operation in Operational Example 1 of the first embodiment will be described below with reference to  FIG. 5  to FIG.  10 . Subsequently, a case in which distribution information is distributed from the server  100  to the client group  300   1  by a circulation system using the distribution communication block  800  will be described below. In step SB 1  shown in  FIG. 6 , the collection and distribution controller  130  in the server  100  calls the communication block forming unit  150 . 
   In this manner, in step SA 1  shown in  FIG. 5 , the communication block forming unit  150  determines a processing type (normal collection and distribution processing, retry distribution processing, and cancel processing). As the normal collection and distribution processing, distribution processing using the distribution communication block  800  and collection processing using the collection communication block  900  are known. 
   In this case, when it is assumed that distribution processing designated by the collection and distribution controller  130 , in step SA 6 , the communication block forming unit  150  forms the distribution communication block  800  shown in  FIG. 3  from the basic communication block  700  (see FIG.  2 ), and then sets a collection and distribution ID  720  for normal collection and distribution is set in the distribution communication block  800 . When cancel processing is designated, in step SA 8 , the communication block forming unit  150  sets a collection and distribution ID  720  for canceling. 
   In step SA 7 , the communication block forming unit  150  sets all the pieces of circulation destination information  742   0  to  742   n  shown in FIG.  3 . More specifically, as destinations of circulation using the distribution communication block  800 , all the relay client  400  and the clients  600   1  to  600   n  shown in  FIG. 1  are set. 
   In step SA 4 , the communication block forming unit  150  determines whether distribution processing is performed by the control of the collection and distribution controller  130 . In this case, it is assumed that the determination result is set to be “Yes”. In step SA 5 , the communication block forming unit  150  sets distribution information (e.g., computer program) in the distribution information region  760  shown in  FIG. 3 , and gives the formed distribution communication block  800  to the collection and distribution controller  130 . 
   In this manner, in step SB 2  shown in  FIG. 6 , the collection and distribution controller  130  calls the transmission processor  170 . More specifically, the collection and distribution controller  130  gives the distribution communication block  800  formed by the communication block forming unit  150  to the transmission processor  170 . In this manner, in step A 1  shown in  FIG. 10 , the transmission processor  170  of the server  100  transmits the distribution communication block  800  to the relay client  400  through the Internet  200 . 
   When the distribution communication block  800  is received by the reception processor  410  of the relay client  400  shown in  FIG. 1 , in step A 2 , the relay client  400  copies distribution information set in the distribution information region  760  of the distribution communication block  800  shown in  FIG. 3 , and sets the result of distribution in the result management information region  748   n . 
   More specifically, in step SD 1  shown in  FIG. 8 , the collection and distribution controller  420  of the relay client  400  calls the reception processor  410  to cause the reception processor  410  to receive the distribution communication block  800 . In step SD 2 , the collection and distribution controller  420  calls the data processor  430  to cause the data processor  430  to perform data processing to the distribution communication block  800 . In this manner, the data processor  430  copies distribution information set in the distribution information region  760  of the distribution communication block  800  shown in  FIG. 3 , and then stores the copy in the data storage unit  440 . 
   In step SD 3 , the collection and distribution controller  420  calls the circulation controller  450 . In this manner, in step SE 1  shown in  FIG. 9 , the circulation controller  450  sets “normal” as a result of distribution in the result management information region  748   0  shown in FIG.  3 . The circulation controller  450  sets “undistributed” in the collection and distribution management flag  746   0 . In step SE 2 , the circulation controller  450  refers to the circulation information region  740  shown in FIG.  3  and refers to the next circulation destination information  742   1 . The circulation destination information  742   1  is information related to the client  600   1  which is the next circulation destination. 
   In step SE 3 , the circulation controller  450  determines whether “undistributed” is set in the collection and distribution management flag  746   1  of the circulation destination information  742   1  which is referred to in step SE 2 . In this case, the determination result is set to be “Yes”. In step SE 4 , the circulation controller  450  determines whether the distribution communication block  800  can be transmitted to the client  600   1  which is the next circulation destination. In this case, the determination result is set to be “Yes”. If the determination result in step SE 4  is “No”, in step SE 7 , the circulation controller  450  waits a predetermined period of time on the basis of time measurement by a timer (not shown). 
   In step SE 5 , the circulation controller  450 , for example, uses a ping command or the like to determine whether the client  600   1  which is the next circulation destination operates or not. If the determination result is “No”, the circulation controller  450  executes processing subsequent to step SE 2  related to the client  600   2  which is the next circulation destination. In this case, if the determination result in step SE 5  is “Yes”, in step SE 6 , the circulation controller  450  requests of the transmission processor  460  that the distribution communication block  800  is transmitted to the next client  600   1 . 
   In this manner, in step A 3  shown in  FIG. 10 , the transmission processor  460  transmits the distribution communication block  800  to the client  600  through the LAN  500 . In parallel to the transmission operation, in step SD 4  shown in  FIG. 8 , the collection and distribution controller  420  determines whether a client in which the collection and distribution controller  420  is incorporated is the relay client  400  or not. In this case, the determination result is set to be “Yes”. In step SD 5 , the collection and distribution controller  420  calls the transmission processor  480 . At this time, any information is not transmitted from the transmission processor  480 . 
   In step SD 6 , the collection and distribution controller  420  transmits the distribution communication block  800  to the server  100  to determine whether a status of distribution is notified or not. In this case, the determination result is set to be “No”. In step SD 7 , the collection and distribution controller  420  calls the reception processor  470 . In this manner, the reception processor  470  is set in a reception waiting state. Subsequently, the loop of step SD 4  to SD 7  is repeated. 
   When the distribution communication block  800  is received by the reception processor  610  of the client  600   1 , in step A 4  shown in  FIG. 10 , the client  600   1  copies distribution information set in the distribution information region  760  of the distribution communication block  800  shown in  FIG. 3  to set a result of distribution in the result management information region  748   1 . 
   More specifically, in step SD 1  shown in  FIG. 8 , the collection and distribution controller  620  of the client  600   1  calls the reception processor  610  to cause the reception processor  610  to receive the distribution communication block  800 . In step SD 2 , the collection and distribution controller  620  calls the data processor  630  to cause the data processor  630  to perform data processing to the distribution communication block  800 . In this manner, the data processor  630  copies distribution information set in the distribution information region  760  of the distribution communication block  800  shown in  FIG. 3 , and then the copy in the data storage unit  640 . 
   In step SD 3 , the collection and distribution controller  620  calls the circulation controller  650 . In this manner, in step SE 1  shown in  FIG. 9 , the circulation controller  650  sets “normal” as a result of distribution in the result management information region  748   1  shown in FIG.  3 . The circulation controller  650  sets “distributed” in the collection and distribution management flag  746   1 . In step SE 2 , the circulation controller  650  refers to the circulation information region  740  shown in FIG.  3  and refers to the next circulation destination information (not shown). The circulation destination information is information related to the client  600   2  which is the next circulation destination. 
   In step SE 3 , the circulation controller  650  determines whether “undistributed” is set as a collection and distribution flag of the circulation destination information which is referred to in step SE 2 . In this case, the determination result is set to be “Yes”. In step SE 4 , the circulation controller  650  determines whether the distribution communication block  800  can be transmitted to the client  6002  which is the next circulation destination. In this case, the determination result is set to be “Yes”. If the determination result in step SE 4  is “No”, in step SE 7 , the circulation controller  650  waits a predetermined period of time on the basis of time measurement by the timer. 
   In step SE 5 , the circulation controller  650 , for example, uses a ping command or the like to determine whether the client  600   2  which is the next circulation destination operates or not. If the determination result is “No”, the circulation controller  650  executes processing subsequent to step SE 2  related to the client  600   3  which is the next circulation destination. In this case, if the determination result in step SE 5  is “Yes”, in step SE 6 , the circulation controller  650  requests of the transmission processor  660  that the distribution communication block  800  is transmitted to the next client  600   2 . 
   In this manner, in step A 5  shown in  FIG. 10 , the transmission processor  660  transmits the distribution communication block  800  to the client  600   2  through the LAN  500 . In parallel to the transmission operation, in step SD 4  shown in  FIG. 8 , the collection and distribution controller  620  determines whether a client in which the collection and distribution controller  620  is incorporated is the relay client  400  or not. In this case, the determination result is set to be “No”. 
   Thereafter, in steps subsequent to step A 6  shown in  FIG. 10 , by the same operation as described above, copying of distribution information, setting of a result, and transmission (circulation) of the distribution communication block  800  to a client which is the next circulation destination are sequentially performed. When the distribution communication block  800  is received by the client  600   n  which is the final circulation destination, in step A 8 , the client  600   n  copies distribution information and sets a result in the same operation as described above. In step A 9 , the client  600   n  transmits the distribution communication block  800  to the relay client  400  through the LAN  500 . 
   When the distribution communication block  800  is received by the reception processor  470  of the relay client  400  in step SD 7  shown in  FIG. 8 , the collection and distribution controller  420  sets the determination result in step SD 4  to be “Yes”, and then gives the distribution communication block  800  to the transmission processor  480  in step SD 5 . In this manner, in step A 10  shown in  FIG. 10 , the transmission processor  480  transmits the distribution communication block  800  to the server  100  through the Internet  200 . In addition, the collection and distribution controller  420  sets the determination result in step SD 6  to be “Yes” to end the series of processes. 
   When the distribution communication block  800  is received by the reception processor  180  of the server  100 , in step SB 3  shown in  FIG. 6 , the collection and distribution controller  130  calls the result management unit  190 . In this manner, in step SC 1  shown in  FIG. 7 , the result management unit  190  receives the distribution communication block  800 . In step SC 2 , the result management unit  190  decides the type of the collection and distribution ID  720  (see  FIG. 3 ) of the distribution communication block  800 . 
   In this case, since the collection and distribution ID  720  is a collection and distribution ID for normal collection and distribution, in step SC 3 , the result management unit  190  holds results of distribution (normal or abnormal) with reference to result management information regions  478 , to  478 , of the pieces of circulation destination information  742   0  to  742   n  of the distribution communication block  800 . In step SC 4 , the result management unit  190  increments a result distributed counter (not shown) by the number of times which the results are normal. 
   As a result, the result distributed counter is to count clients to which pieces of information are normally distributed in the series of distribution processes for the relay client  400  and the clients  600   1  to  600   n . In this case, the count value of the result distributed counter is set at n+1. More specifically, the pieces of distribution information are distributed to all the relay client  400  and the clients  600   1  to  600   n . 
   In step SC 5 , the result management unit  190  determines whether the count result (in this case, n+1) of the result distributed counter is equal to the number of all clients (in this case, n+1) or not. In this case, the determination result is set to be “Yes” to end the series of processes. When the collection and distribution ID  720  is a collection and distribution ID for canceling, in step SC 6 , the result management unit  190  clears the result of distribution set in the result management information region of the distribution communication block. 
   A collection operation in Operational Example 1 of the first embodiment will be described below with reference to  FIG. 5  to FIG.  9  and FIG.  11 . In the following description, a case in which pieces of collection information are collected from the relay client  400  and the clients  600   1  to  600   n  by a circulation system using the collection communication block  900  shown in FIG.  4 . In step SB 1  shown in  FIG. 6 , the collection and distribution controller  130  of the server  100  calls the communication block forming unit  150 . 
   In this case, when collection processing is designated by the collection and distribution controller  130 , in step SA 6  shown in  FIG. 5 , the communication block forming unit  150  forms the collection communication block  900  formed from the basic communication block  700  (see  FIG. 2 ) and shown in  FIG. 4 , and then sets the collection and distribution ID  720  for normal collection and distribution in the collection communication block  900 . 
   In step SA 7 , the communication block forming unit  150 , as destinations of circulation using the collection communication block  900 , all the relay client  400  and the clients  600   1  to  600   n  shown in  FIG. 1  are set. In step SA 4 , the communication block forming unit  150  determines whether distribution processing is performed by the control of the collection and distribution controller  130  or not. In this case, since collection processing is performed, the communication block forming unit  150  sets the determination result to be “No” and gives the formed collection communication block  900  to the collection and distribution controller  130 . 
   In this manner, in step SB 2  shown in  FIG. 6 , the collection and distribution controller  130  gives the collection communication block  900  formed by the communication block forming unit  150  to the transmission processor  170  to make a transmission request. In this manner, in step B 1  shown in  FIG. 11 , the transmission processor  170  of the server  100  transmits the collection communication block  900  to the relay client  400  through the Internet  200 . 
   When the collection communication block  900  is received by the reception processor  410  of the relay client  400  shown in  FIG. 1 , in step B 2 , the relay client  400  sets collection information in the collection information region  780  of the collection communication block  900  shown in  FIG. 4 , and sets a result of collection (in this case, normal) in the result management information region  748   0 . 
   More specifically, in step SD 1  shown in  FIG. 8 , the collection and distribution controller  420  of the relay client  400  calls the reception processor  410  to cause the reception processor  410  to receive the collection communication block  900 . In step SD 2 , the collection and distribution controller  420  calls the data processor  430  to cause the data processor  430  to perform data processing to the collection communication block  900 . In this manner, the data processor  430  sets collection information in the collection information region  780  of the collection communication block  900  shown in FIG.  4 . 
   In step SD 3 , the circulation controller  450  is called. In this manner, in step SE 1  shown in  FIG. 9 , the circulation controller  450  sets collection information in the collection information  783 , shown in  FIG. 4 , and sets “normal” as a result of collection in the result management information region  748   0 . In step SE 2 , the circulation controller  450  refers to the circulation information region  740  shown in FIG.  4  and refers to the next circulation destination information  7421 . The circulation destination information  742   1  is information related to the client  600   1  which is the next circulation destination. 
   In step SE 3 , the circulation controller  450  determines whether “uncollected” is set in the collection and distribution management flag  746   1  of the circulation destination information  742   1  which is referred to in step SE 2 . In this case, the determination result is set to be “Yes”. In step SE 4 , the circulation controller  450  determines whether the collection communication block  900  can be transmitted to the client  600   1  which is the next circulation destination. In this case, the determination result is set to be “Yes”. If the determination result in step SE 4  is “No”, in step SE 7 , the circulation controller  450  waits a predetermined period of time on the basis of time measurement by the timer. 
   In step SE 5 , the circulation controller  450 , for example, uses a ping command or the like to determine whether the client  600   1  which is the next circulation destination operates or not. If the determination result is “No”, the circulation controller  450  executes processing subsequent to step SE 2  related to the client  600   2  which is the next circulation destination. In this case, if the determination result in step SE 5  is “Yes”, in step SE 6 , the circulation controller  450  requests of the transmission processor  460  that the collection communication block  900  is transmitted to the next client  600   1 . 
   In this manner, in step B 3  shown in  FIG. 11 , the transmission processor  460  transmits the collection communication block  900  to the client  600  through the LAN  500 . In parallel to the transmission operation, in step SD 4  shown in  FIG. 8 , the collection and distribution controller  420  determines whether a client in which the collection and distribution controller  420  is incorporated is the relay client  400  or not. In this case, the determination result is set to be “Yes”. In step SD 5 , the collection and distribution controller  420  calls the transmission processor  480 . At this time, any information is not transmitted from the transmission processor  480 . 
   In step SD 6 , the collection and distribution controller  420  transmits the collection communication block  900  to the server  100  to determine whether a status of collection is notified or not. In this case, the determination result is set to be “No”. In step SD 7 , the collection and distribution controller  420  calls the reception processor  470 . In this manner, the reception processor  470  is set in a reception waiting state. Subsequently, the loop of step SD 4  to SD 7  is repeated. 
   When the collection communication block  900  is received by the reception processor  610  of the client  600   1 , in step B 4 , as in step B 2 , the client  600   1  sets collection information in the collection information region  780  of the collection communication block  900  shown in FIG.  4  and sets a result of collection in the result management information region  748   1 . 
   More specifically, in step SD 1  shown in  FIG. 8 , the collection and distribution controller  620  of the client  600   1  calls the reception processor  610  to cause the reception processor  610  to receive the collection communication block  900 . In step SD 2 , the collection and distribution controller  620  calls the data processor  630  to cause the data processor  630  to perform data processing to the collection communication block  900 . In this manner, the data processor  630  sets collection information in the collection information region  780  of the collection communication block  900  shown in FIG.  4 . 
   In step SD 3 , the circulation controller  650  is called. In this manner, in step SE 1  shown in  FIG. 9 , the circulation controller  650  sets “collected as a result of collection in the result management information region  748   0  shown in FIG.  4 . In step SE 2 , the circulation controller  650  refers to the circulation information region  740  shown in FIG.  4  and refers to the next circulation destination information (not shown). The circulation destination information is information related to the client  600   2  which is the next circulation destination. 
   In step SE 3 , the circulation controller  650  determines whether “uncollected” is set as the collection and distribution flag  746   1  of the circulation destination information which is referred to in step SE 2 . In this case, the determination result is set to be “Yes”. In step SE 4 , the circulation controller  650  determines whether the collection communication block  900  can be transmitted to the client  600   2  which is the next circulation destination. In this case, the determination result is set to be “Yes”. If the determination result in step SE 4  is “No”, in step SE 7 , the circulation controller  650  waits a predetermined period of time on the basis of time measurement by the timer. 
   In step SE 5 , the circulation controller  650 , for example, uses a ping command or the like to determine whether the client  600 Z which is the next circulation destination operates or not. If the determination result is “No”, the circulation controller  650  executes processing subsequent to step SE 2  related to the client  600   3  which is the next circulation destination. In this case, if the determination result in step SE 5  is “Yes”, in step SE 6 , the circulation controller  650  requests of the transmission processor  660  that the collection communication block  900  is transmitted to the next client  600   2 . 
   In this manner, in step B 5  shown in  FIG. 11 , the transmission processor  460  transmits the collection communication block  900  to the client  6002  through the LAN  500 . In parallel to the transmission operation, in step SD 4  shown in  FIG. 8 , the collection and distribution controller  620  determines whether a client in which the collection and distribution controller  620  is incorporated is the relay client  400  or not. In this case, the determination result is set to be “No”. 
   Thereafter, in steps subsequent to step B 6  shown in  FIG. 11 , by the same operation as described above, setting of collection information, setting of a result, and transmission (circulation) of the collection communication block  900  to a client which is the next circulation destination are sequentially performed. When the collection communication block  900  is received by the client  600   n  which is the final circulation destination, in step B 8 , the client  600   n  performs setting of collection information and setting of a result by the same operation as described above. In step B 9 , the client  600   n  transmits the collection communication block  900  to the relay client  400  through the LAN  500 . 
   When the collection communication block  900  is received by the reception processor  470  of the relay client  400  in step SD 7  shown in  FIG. 8 , the collection and distribution controller  420  sets the determination result in step SD 4  to be “Yes”, and then gives the collection communication block  900  to the transmission processor  480  in step SD 5 . In this manner, in step B 10  shown in  FIG. 11 , the transmission processor  480  transmits the collection communication block  900  to the server  100  through the Internet  200 . In addition, the collection and distribution controller  420  sets the determination result in step SD 6  to be “Yes” to end the series of processes. 
   When the collection communication block  900  is received by the reception processor  180  of the server  100 , in step SB 3  shown in  FIG. 6 , the collection and distribution controller  130  calls the result management unit  190 . In this manner, in step SC 1  shown in  FIG. 7 , the result management unit  190  receives the collection communication block  900 . In step SC 2 , the result management unit  190  decides the type of the collection and distribution ID  720  (see  FIG. 4 ) of the collection communication block  900 . 
   In this case, since the collection and distribution ID  720  is a collection and distribution ID for normal collection and distribution, in step SC 3 , the result management unit  190  holds results of distribution (collected or uncollected) with reference to result management information regions  478   0  to  478   n  of the pieces of circulation destination information  742   0  to  742   n  of the collection communication block  900 . In step SC 4 , the result management unit  190  increments a result distributed counter by the number of times which the results are collected. 
   In this case the count value of the result collected counter is set to be n+1. More specifically, pieces of collection information are normally collected from all the relay client  400  and the clients  600   1  to  600   n . In step SC 5 , the result management unit  190  determines whether the count result (in this case, n+1) of the result collected counter is equal to the number of all clients (in this case n+1). In this case, the determination result is set to be “Yes” to end the series of processes. 
   In the distribution operation described with reference to  FIG. 10 , if the determination result of step SC 5  shown in  FIG. 7  is “No”, that is, if a result of distribution of the relay client  400  and the clients  600   1  to  600   n  is “abnormal”, a retry distribution operation (see  FIG. 12 ) which distribution information is distributed to the abnormal” client again is performed. 
   More specifically, when the communication block forming unit  150  is called by the collection and distribution controller  130  of the server  100  in step SB 1  shown in  FIG. 6 , in step SA 1  shown in  FIG. 5 , the communication block forming unit  150  determines a processing type (normal collection and distribution processing, retry distribution processing, and cancel processing). 
   In this case, it is assumed that the retry distribution processing is designated by the collection and distribution controller  130 . At this time, in step SA 2 , the communication block forming unit  150  forms a retry distribution communication block (not shown) shown in  FIG. 3  from the basic communication block  700  (see FIG.  2 ), and then sets the collection and distribution ID  720  for retry in the retry distribution communication block. The basic data structure of the retry distribution communication block is the same as that of the distribution communication block  800  (see FIG.  3 ). Therefore, the retry distribution communication block will be described below with reference to the distribution communication block  800 . 
   In step SA 3 , the communication block forming unit  150  resets a circulation destination information a result of distribution of which is “abnormal” in the circulation destination information  742   0  to  742   n  shown in FIG.  3 . In this case, it is assumed that the results of distribution related to the relay client  400  and the clients  600   3  to  600   n-1  (not shown) are “normal”. On the other hand, it is assumed that the results of distribution of the clients  600   1 ,  600   2 , and  600   n  are “abnormal”. 
   In step SA 4 , the communication block forming unit  150  determines whether (retry) distribution processing is performed by the control of the collection and distribution controller  130  or not. In this case, the decision result is set to be “Yes”. In step SA 5 , the communication block forming unit  150  sets distribution information in the distribution information region  760  shown in  FIG. 3 , and gives a formed retry distribution communication block to the collection and distribution controller  130 . 
   In this manner, in step SB 2  shown in  FIG. 6 , the collection and distribution controller  130  calls the transmission processor  170 . More specifically, the collection and distribution controller  130  gives a retry distribution communication block formed by the communication block forming unit  150  to the transmission processor  170  to make a transmission request. In this manner, in step C 1  shown in  FIG. 12 , the transmission processor  170  of the server  100  transmits the retry distribution communication block to the relay client  400  through the Internet  200 . 
   When the retry distribution communication block is received by the reception processor  410  of the relay client  400  shown in  FIG. 1 , in step C 2 , the relay client  400  relays the retry distribution communication block to the client  600   1 . More specifically, in step C 3 , since the relay client  400  has received distribution information, the retry distribution communication block is transmitted to the client  600   1  (abnormal). 
   When the retry distribution communication block is received by the client  600   1 , in step C 4 , the client  600   1  copies distribution information set in the distribution information region  760  of the retry distribution communication block shown in FIG.  3  and sets a result of distribution in the result management information region  748   1 . In step C 5 , the client  600   1  transmits the retry distribution communication block to the client  600   2  (abnormal). 
   When the retry distribution communication block is received by the client  600   2 , in step C 6 , the client  600   2  copies distribution information set in the distribution information region  760  of the retry distribution communication block shown in FIG.  3  and sets a result of distribution in the result management information region  748   1 . In step C 6 , the client  6002  transmits the retry distribution communication block to the client  600   n  (abnormal). 
   When the retry distribution communication block is received by the client  600   n , in step C 8 , the client  600   n  performs copying of distribution information and setting of a result by the same operation as described above. In step C 9 , the client  600   n  transmits the retry distribution communication block to the relay client  400  through the LAN  500 . 
   When the retry distribution communication block is received by the relay client  400  in step SD 7  shown in  FIG. 8  in step C 10 , the collection and distribution controller  420  causes the relay client  400  to the server  100  transmit the retry distribution communication block to through the Internet  200 . 
   When the retry distribution communication block is received by the reception processor  180  of the server  100 , in the result management unit  190 , processing related to the retry distribution communication block is executed according to the flow chart shown in FIG.  7 . Although the retry distribution operation has been described above, a retry operation may be performed in case of collection by the same operation as the retry distribution operation. 
   In Operational Example 1 of the first embodiment described above, the following example has been described. That is, in a distribution operation (see  FIG. 10 ) or a collection operation (see FIG.  11 ), when the distribution communication block  800  or the collection communication block  900  is received by the client  600   n  which is the final circulation distribution, the distribution communication block  800  or the collection communication block  900  is transmitted to the server  100  through the relay client  400 , so that a result of collection and distribution is notified. However, the result of collection and distribution is intermediately notified in the middle of collection and distribution. This case will be described below as Operational Example 2 of the first embodiment. 
   Operational Example 2 of the first embodiment will be described below with reference to  FIGS. 13 and 14 .  FIG. 14  is a sequence diagram for explaining a distribution operation in Operational Example 2 of the first embodiment. A collection operation which performs intermediate notification is also performed by the same manner as that of the distribution operation (to be described later). 
   In step D 1  shown in  FIG. 14 , the server  100  transmits the distribution communication block  800  to the relay client  400  through the Internet  200 . When the distribution communication block  800  is received by the relay client  400  shown in  FIG. 1 , in step D 2 , the relay client  400  copies distribution information set in the distribution information region  760  of the distribution communication block  800  and sets a result of distribution in the result management information region  748   0  as in Operational Example 1. 
   More specifically, in step SF 1  shown in  FIG. 13 , the circulation controller  450  of the relay client  400  sets “normal” as a result of distribution in the result management information region  748   0  shown in FIG.  3 . In step SF 2 , the circulation controller  450  refers to the circulation information region  740  shown in FIG.  3  and refers to the next circulation destination information  742   1 . In step SF 3 , the circulation controller  450  determines whether “undistributed” in the collection and distribution management flag  746   1  of the circulation destination information  742   1  which is referred to in step SF 2  or not. In this case, the determination result is set to be “Yes”. 
   In step SF 4 , the circulation controller  450  determines whether the distribution communication block  800  is transmitted to the client  600   1  which is the next circulation destination or not. In this case, the determined result is set to be “Yes”. In step SF 5 , the circulation controller  450  uses, for example, uses a ping command or the like to determine whether the client  600   1  which is the next circulation destination operates or not. In this case, the determination result is set to be “Yes”. 
   In step SF 6 , the circulation controller  450  requests of the transmission processor  460  that the distribution communication block  800  is transmitted to the next client  6001 . In this manner, in step D 3  shown in  FIG. 14 , the transmission processor  460  transmits the distribution communication block  800  to the client  600   1  through the LAN  500 . 
   When the distribution communication block  800  is received by the reception processor  610  of the client  600   1 , in step D 4  shown in  FIG. 14 , the client  600   1  copies distribution information set in the distribution information region  760  of the distribution communication block  800  shown in FIG.  3  and sets a result of distribution in the result management information region  748   1 . In step D 5 , the client  600   1  transmits the distribution communication block  800  to the client  600   2  through the LAN  500 . 
   When the distribution communication block  800  is received by a reception processor (not shown) of the client  600   2 , in step D 6 , the client  600   2  copies distribution information set in the distribution information region  760  of the distribution communication block  800  shown in FIG.  3  and sets a result of distribution in the result management information region  7482  (not shown). 
   More specifically, in step SF 1  shown in  FIG. 13 , the circulation controller (not shown) of the client  600   2  sets “normal” as a result of distribution in the result management information region of the distribution communication block  800 . In step SF 2 , the circulation controller  650  refers to the circulation information region  740  shown in FIG.  3  and refers to next circulation destination information (not shown). This circulation destination information is information related to the client  600   3  (not shown) which is the next circulation destination. 
   In step SF 3 , the circulation controller determines whether “undistributed” in the collection and distribution management flag of the circulation destination information which is referred to in step SF 2  or not. In this case, the determination result is set to be “Yes”. In step SF 4 , the circulation controller determines whether the distribution communication block  800  can be transmitted to the client  600   3  (not shown) which is the next circulation destination. In this case, if the client  600   3  is defective, the circulation controller sets the determination result in step SF 4  to be “No”. 
   In step SF 7 , the circulation controller copies the distribution communication block  800 . In step SF 8 , the circulation controller requests of the transmission processor  460  that the distribution communication block  800  for intermediate notification is transmitted to the relay client  400 . In this manner, in step SD 7  shown in  FIG. 14 , the transmission processor of the client  600   2  transmits the distribution communication block  800  for intermediate notification to the relay client  400  through the LAN  500 . 
   When the distribution communication block  800  for intermediate notification is received by the relay client  400 , in step D 8 , the relay client  400  transmits the distribution communication block  800  to the server  100  through the Internet  200 . In this manner, intermediate notification of a result of distribution is performed to the server  100  through the operation described above. 
   In step SF 9  shown in  FIG. 13 , the circulation controller of the client  600   2  waits a predetermined period of time. In step SF 5 , the circulation controller, for example, uses a ping command or the like to determine whether the client  600   3  which is the next circulation destination operates or not. In this case, the determination result is set to be “No”, the circulation controller executes processes subsequent to step SF 2  related to the client  600   4  which is the next circulation destination. 
   In this case, if the determination result in step SF 5  is “Yes”, in step SF 6 , the circulation controller requests of the transmission processor that the distribution communication block  800  is transmitted to the client  600   3 . Thereafter, in step D 9  to step D 12  shown in  FIG. 14 , the same processes as those in step A 7  to step A 10  shown in  FIG. 10  are performed. 
   In Operational Example 1 of the first embodiment described above, the case in which one distribution communication block  800  (or collection communication block  900 ) is transmitted to one group constituted by the relay client  400  shown in FIG.  1  and the clients  600   1  to  600   n  has been explained. However, as shown in  FIG. 15 , the relay client  400  and the clients  600   1  to  600   n  may be partitioned into groups G 1  to G x , and collection and distribution may be performed to each group. This case will be described below as Operational Example 3 of the first embodiment. 
   The group G 1  shown in  FIG. 15  is constituted by clients  600   1  to  600   h  belonging to a segment SG 1  of the LAN  500 . A group G 2  is constituted by clients  600   i  (i&gt;h) to  600   j  (J&gt;) belonging to a segment SG 2 . A group G x  is constituted by clients  600   k  (k&gt;J) to  600   n  (n&gt;k) belonging to a segment SG x . In this example, the number of partitions (the number of groups) of a relay client  400  and the clients  600   1  to  600   n  is x. 
   In the arrangement described above, when the distribution communication block  800  (see  FIG. 18A ) is formed by the communication block forming unit  150  of the server  100  shown in  FIG. 15 , in step E 1  shown in  FIG. 19 , the transmission processor  170  of the server  100  transmits the distribution communication block  800  to the relay client  400  through the Internet  200 . 
   When the distribution communication block  800  is received by the reception processor  410  of the relay client  400  shown in  FIG. 1 , in step E 2 , the relay client  400  copies distribution information and sets the result of distribution. In step E 3 , the relay client  400  forms partition distribution communication blocks  800   1  to  800   n  shown in  FIG. 18B  to FIG.  18 D. 
   More specifically, the collection and distribution controller  420  of the relay client  400  calls the data processor  430  to cause the data processor  430  to perform data processing to the distribution communication block  800 . In this manner, the data processor  430  copies distribution information set in the distribution information region  760  of the distribution communication block  800  shown in  FIG. 18A , and then stores the copy in the data storage unit  440 . 
   The collection and distribution controller  420  calls the circulation controller  450 . In this manner, in step SG 1  shown in  FIG. 16 , the circulation controller  450  of the relay client  400  determines whether partition distribution is designated by the collection and distribution controller  420  or not. If the determination result is “No”, in step SG 16 , the circulation controller  450  executes normal distribution processing which is the same as that in Operational Example 1 of the first embodiment. In step SG 17 , the circulation controller  450  calls the reception processor  470 . 
   In this case, when partition distribution is designated by the collection and distribution controller  420 , in step SG 2 , the circulation controller  450  sets “normal” as a result of distribution in the result management information region  748   0  shown in FIG.  3 . The process in step SG 1  is the same as the process in step SE 1  (see FIG.  9 ). In step SG 3 , the circulation controller  450  calls the partition processor  490 . 
   In this manner, in step SH 1  shown in  FIG. 17 , the partition processor  490  forms the partition distribution communication blocks  800   1  to  800   x  shown in  FIGS. 18B  to  18 D from the distribution communication block  800  shown in  FIG. 18A  by copy. Each of the data structures of the partition distribution communication blocks  800   1  to  800   x  is the same as the data structure of the distribution communication block  800 . The partition distribution communication blocks  800   1  to  800   x  correspond to groups G 1  to G x  belonging to segments SG 1  to SG x  shown in FIG.  15 . In step SG 2 , the partition processor  490  refers to the circulation information region  740  (see  FIG. 3 ) of the distribution communication block  800 . 
   In step SH 3 , the partition processor  490  sets circulation destination information in the circulation information region  740   1  of the partition distribution communication block  800   1  on the basis of a partition condition designated by the collection and distribution controller  420 . The partition condition mentioned here is that the clients  600   1  to  600   n  shown in  FIG. 15  are partitioned into groups G 1  to G x . For this reason, in the circulation information region  740   1  of the partition distribution communication block  800   1  shown in  FIG. 18B , pieces of circulation destination information (client names, addresses, and the like) related to the clients  600   1  to  600   n  in the group G 1  shown in FIG.  15 . 
   In step SH 4 , the partition processor  490  determines whether partition is completed or not. In this case, the determination result is set to be “No”. Thereafter, the processes in step SH 2  and SH 3  are repeated. In this manner, in the circulation information region  740   2  of the partition distribution communication block  800   2  (see FIG.  18 C), pieces of circulation destination information (client names, addresses, and the like) related to clients  600   i  to 600 j  in the group G 2  are set. In the same manner as described above, pieces of circulation destination information (client names, addresses, and the like) related to the clients  600   k  to 600 n  in the group G x  shown in  FIG. 18D  are set in the circulation information region  740   x  of the partition distribution communication block  800   x  (see FIG.  18 D). 
   When the determination result in step SH 4  becomes “Yes”, the partition processor  490  copies the distribution information set in the distribution information region  760  (see  FIG. 18A ) of the distribution communication block  800  to the distribution information regions  760  of the partition distribution communication blocks  800   1  to  800   x , respectively. 
   In step SG 4  shown in  FIG. 16 , the circulation controller  450  refers to the partition distribution communication block  800   1  (see FIG.  18 B). In step SG 5 , the circulation controller  450  checks the operation of a circulation destination (in this case, the client  600   1 ) which is set first in the circulation information region  740   1  to perform monitoring with a timer. In step SG 5 , the circulation controller  450  calls the transmission processor  460  and requests of the transmission processor  460  that the partition distribution communication block  800   1  is transmitted to the client  600   1 . In this manner, the transmission processor  460  transmits the partition distribution communication block  800   1  to the client  600   1  through the LAN  500  (step E 3 : see FIG.  19 ). 
   In step SG 7 , the circulation controller  450  increments a transmission counter for counting the number of transmitted partition distribution communication blocks by 1. In step SG 8 , it is determined whether the count value of the transmission counter is equal to the number of partitions (in this case, x) or not. In this case, the determination result is set to be “No”. 
   Thereafter, when the processes in step SG 4  to step SG 7  are repeated, the partition distribution communication blocks  800   2 , . . . ,  800   x  are transmitted from the transmission processor  460  of the relay client  400  to the clients  600   i , . . . ,  600   k , respectively, (step E 4 : see FIG.  19 ). When the determination result in step SG 8  becomes “Yes”, in step SG 9 , the relay client  400  calls the reception processor  470  to set in a reception waiting state. 
   When the partition distribution communication block  8001  is received by the client  600   1 , in step E 5  shown in  FIG. 19 , the client  600   1  copies the distribution information set in the distribution information region  760  of the partition distribution communication block  800   1  shown in FIG.  18 B and sets a result of distribution in a result management information region (not shown). In step E 6 , the client  600   1  transmits the partition distribution communication block  800   1  to the client  600   2 . 
   Thereafter, the partition distribution communication block  800   1  is sequentially circulated. When the partition distribution communication block  800   1  is received by the client  600   h  which is the final circulation destination in the group G 1 , in step E 7 , the client  600   h  copies the distribution information and sets a result. In step E 8 , the client  600   h  transmits the partition distribution communication block  800   1  to the relay client  400  through the LAN  500 . 
   In parallel to the processes in steps E 5  to E 8  described above, the processes in step E 9  to step E 12  are executed in the group G 2 , and the processes in step E 13  to step E 16  in the group G x . In this manner, the partition distribution communication blocks  800   2  and  800   x  are transmitted from the clients  600   1  and  600   x  to the relay client  400 . 
   When the partition distribution communication blocks  800   1  to  800   x  are received by the relay client  400 , in step E 17 , the relay client  400  merges the partition distribution communication blocks  800   1  to  800   x . More specifically, the partition distribution communication block  800   1  is received by the reception processor  470 , in step SG 10  shown in  FIG. 16 , the circulation controller  450  increments a received counter for counting received distribution communication blocks by 1. 
   In step SG 11 , the circulation controller  450  refers to a result of distribution related to the group G 1  from the circulation destination information  742   1  (see  FIG. 18B ) of the partition distribution communication block  800   1 . In step SG 12 , the circulation controller  450  sets a result of distribution related to the group G 1  in the circulation information region  740  (see  FIG. 18A ) of the distribution communication block  800 . In step SG 13 , the circulation controller  450  determines whether collection processing is performed or not. In this case, the determination is set to be “No”. If the determination result in step SG 13  is “No”, in step SG 14 , the circulation controller  450  sets collection information related to the group G 1  in the collection communication block. 
   In step SG 15 , the circulation controller  450  determines whether the count result of the received counter is equal to the number of partitions (=x). In this case, the determination result is set to be “No”. Thereafter, each time the partition distribution communication blocks  800   2  to  800   x  are received by the reception processor  470 , the processes in step SG 9  to step SG 12  described above are executed. When merging related to all the partition distribution communication blocks  800   1  to  800   x  is completed, the circulation controller  450  sets the determination result in step SG 15  to be “Yes”. 
   In this manner, in step E 18  shown in  FIG. 19 , the relay client  400  transmits the distribution communication block  800  (see  FIG. 18A ) to the server  100  through the Internet  200 . Thereafter, as in Operational Example 1 of the first embodiment, result management (see  FIG. 7 ) is executed by the result management unit  190 . 
   As has been described above, according to the first embodiment, when the relaying function is given to the relay client  400 , and circulation of all the distribution communication blocks  800  (or collection communication blocks  900 ) is completed, the distribution communication block  800  (or collection communication block  900 ) to the server  100  in which a distribution result (or collection result) is set is relayed through the relay client  400 . For this reason, unlike a conventional technique, the dedicated server  40  (see  FIG. 24 ) need not be arranged, and, by performing distribution once, the distribution communication block  800  (or collection communication block  900 ) may be transmitted from the LAN  500  to the Internet  200  once. For this reason, a network load can be reduced with a low cost and a high security. 
   According to the first embodiment, when the relaying function is given to the relay client  400 , and circulation of all the distribution communication blocks  800  is completed, the distribution communication block  800  to the server  100  in which a distribution result is set is relayed through the relay client  400 . For this reason, unlike a conventional technique, the dedicated server  40  (see  FIG. 24 ) need not be arranged, and, by performing distribution once, the distribution communication block  800  may be transmitted from the LAN  500  to the Internet  200  once. For this reason, a network load can be reduced with a low cost and a high security. 
   In addition, according to the first embodiment, a client which fails in distribution (or collection) is recognized on the basis of a distribution result (or collection result) set in the distribution communication block  800  (or collection communication block  900 ) related to the first distribution (or collection), and a retry distribution communication block (or retry collection communication block) is retransmitted to the client. For this reason, reliability related to distribution (or collection) can be improved. 
   According to the first embodiment, when the client which is the next circulation destination is stopped in the middle of circulation of the distribution communication block  800  (or collection communication block  900 ), as intermediate notification, the distribution communication block  800  (or collection communication block  900 ) is relayed from the client to the server  100 . For this reason, on the server  100  side, a distribution result (or collection result) can be quickly recognized without waiting for the distribution communication block  800  (or collection communication block  900 ) from the client  600   n  which is the final circulation destination. 
   According to the first embodiment, the relay client  400  and the clients  600   1  to  600   n  are grouped into the groups G 1  to G x , and communication blocks are circulated in each of the groups. For this reason, time required for distribution (or collection can be shortened. 
     FIG. 20  is a block diagram showing the configuration of a second embodiment according to the present invention. The configuration of the second embodiment shown in  FIG. 20  is the concrete example of the first embodiment described above. Therefore, the operation of the second embodiment is the same as the operation of the first embodiment. 
   In  FIG. 20 , a main office network system  1000  is an in-house system installed in a main office, and is constituted by a main office server  1010 , a LAN  1030 , and a fire wall  1040 . The main office server  1010  has a function of distributing pieces of information (e.g., an application program  1020 ) to an employee  0  client  1230   0  to an employee n client  1230   n  and a function of collecting pieces of information from the employee  0  client  1230   0  to the employee n client  1230   n . The configuration and operation of the main office server  1010  are the same as the configuration and operation of the server  100  (see FIG.  1 ). 
   The main office server  1010  is connected to the LAN  1030 . The fire wall  1040  is to prevent illegal access from an external system to the main office network system  1000 , and is designed to cause only pieces of information or protocols to which securities are given to pass. The LAN  1030  is an in-house network installed in the main office, and is connected to Internet  1100  through the fire wall  1040 . 
   A branch office network system  1200  is an in-house system installed in a branch office, and is constituted by a fire wall  1210 , a LAN  1220 , and an employee  0  client  1230   0  to an employee n client  1230   n . The fire wall  1210 , like the fire wall  1040 , is to prevent illegal access to the branch office network system  1200 . 
   The LAN  1220  is an in-house network installed in a branch office, and is connected to the Internet  1100  through the fire wall  1210 . The employee  0  client  1230   0  to the employee n client  1230   n  are computers corresponding to an employee  0  to an employee n (not shown) in the branch office, and are connected to the LAN  1220 . The configuration and operation of the employee  0  client  1230   0  are the same as the configuration and operation of the relay client  400  (see FIG.  1 ). The configuration and operation of the employee  1  client  1230   1  to the employee n client  1230   n  are the same as the configuration and operation of the clients  600   1  to  600   n  (see FIG.  1 ). 
   In this case, in the second embodiment, a distribution communication block  1300  shown at (a) in  FIG. 21  is used. The data structure of the distribution communication block  1300  is the same as that of the distribution communication block  800  (see FIG.  3 ). Therefore, the same reference numerals as in  FIG. 3  denote the same parts in  FIGS. 21A and 21B . The pieces of circulation destination information  742   0  to  742   n  shown at (b) in  FIG. 21  correspond to the employee  0  client  1230   0  to the employee n client  1230   n . 
   For example, as shown at (c) in  FIG. 21 , the circulation destination information  742   0  is constituted by pieces of information, i.e., an “employee” (client name  743   0 ), “123.456.789.001” (address  744   0 ), “undistributed” (collection and distribution management flag  746   0 ), and “undefined” (result management information region  748   0 ). 
   When the distribution communication block  1300  having the circulation information region  740  shown at (c) in  FIG. 21  is transmitted to the employee  0  client  1230   0 , as shown at (d) in  FIG. 21 , transition from “undistributed” to “distributed” occurs in the collection and distribution management flag  746   0 , and transition from “undefined” to “normal” occurs in the result management information region  748   0 . In addition, when the distribution communication block  1300  is transmitted to the employee  1  client  1230   1  which is the next circulation destination, as shown at (e) in  FIG. 21 , transition from “undistributed” to “distributed” occurs in the collection and distribution management flag  746   1 , and transition from “undefined” to “normal” occurs in the result management information region  748   1 . Thereafter, the distribution communication block  1300  is sequentially circulated to the employee  2  client  1230   2  to the employee n client  1230   n . 
   When the distribution communication block  1300  is transmitted to the employee n client  1230   n  which is the final circulation destination, as shown at (f) in  FIG. 21 , transition from “undistributed” to “distributed” occurs in a collection and distribution management flag  746   n , and transition from “undefined” to “normal” occurs in the result management information region  748   n . 
   The first and second embodiments according to the present invention have been described above with reference to the drawings. However, a concrete configuration is not limited to the first and second embodiments, and the invention also includes inventions which change in design without departing from the spirit and scope of the invention. For example, in the first and second embodiments, the following configuration may be used. That is, an information collection and distribution program for realizing the collection and distribution function is recorded on a computer readable recording medium, and the information collection and distribution program recorded on the recording medium is loaded on a computer and executed, so that collection and distribution of information are realized. 
   The computer is constituted by a CPU for executing the information collection and distribution program, an input device such as a keyboard or a mouse, a ROM (Read Only Memory) for storing various data, and a RAM (Random Access Memory) for storing an operation parameter or the like, a reading device for read the information collection distribution program from a recording medium, an output device such as a display or a printer, and a bus BU for connecting the devices to each other. 
   The CPU loads the information collection and distribution program recorded on the recording medium through the reading device and then executes the information collection and distribution program to perform the collection and distribution. The recording medium includes not only a portable recording medium such as an optical disk, a floppy disk, or a hard disk, but also a transmission medium which temporarily records and holds data like a network. 
   As has been described above, according to the present invention, when a relaying function is given to one client of a plurality of clients, and circulation of all communication blocks is completed, a communication block in which a distribution result is set is relayed to a server through one server. For this reason, unlike a conventional technique, a dedicated server need not be arranged, and, by performing distribution once, a communication block may be transmitted from an in-house network to an external network once. Therefore, a network load can be advantageously reduced with a low cost and a high security. 
   Furthermore, a client which fails in distribution is recognized on the basis of a distribution result in a communication block related to the first distribution, so that the communication block is re-transmitted to the client. For this reason, the reliability of distribution can be advantageously improved. 
   In the middle of circulation of a communication block, when the client of the next circulation destination is stopped, as intermediate notification, the communication block from the client is relayed to a server. For this reason, on the server side, a distribution result can be quickly recognized without waiting for the communication block from the client of the final circulation destination. 
   A plurality of clients are grouped, and communication blocks are parallel circulated in the groups. For this reason, time required for distribution can be advantageously shortened. 
   When a relaying function is given to one client of a plurality of clients, and circulation of all communication blocks is completed, a communication block in which a collection result is set is relayed to a server through one server. For this reason, unlike a conventional technique, a dedicated server need not be arranged, and, by performing collection once, a communication block may be transmitted from an in-house network to an external network once. Therefore, a network load can be advantageously reduced with a low cost and a high security. 
   Furthermore, a client which fails in collection is recognized on the basis of a collection result in a communication block related to the first collection, so that the communication block is re-transmitted to the client. For this reason, the reliability of collection can be advantageously improved. 
   In the middle of circulation of a communication block, when the client of the next circulation destination is stopped, as intermediate notification, the communication block from the client is relayed to a server. For this reason, on the server side, a collection result can be quickly recognized without waiting for the communication block from the client of the final circulation destination. 
   A plurality of clients are grouped, and communication blocks are parallel circulated in the groups. For this reason, time required for collection can be advantageously shortened. 
   Although the invention has been described with respect to a specific embodiment for a complete and clear disclosure, the appended claims are not to be thus limited but are to be construed as embodying all modifications and alternative constructions that may occur to one skilled in the art which fairly fall within the basic teaching herein set forth.