JPH11212913A - Inter-object communication system for client and server environment, service agent, service manager, client interface and server interface - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a client to use the servers with no consciousness of the nodes where the servers exist in a client/server environment where plural servers are scattered. SOLUTION: A server agent 3 is prepared in a communication network where plural servers are scattered to perform the communication between a client 1 and the servers. The agent 3 knows the places of servers and receives the service requests from the client 1 to perform the communication in response to the received requests. Thus, the agent 3 makes the servers perform the service processing and then receives these service processing results to return them to the client 1. The client 1 merely issues the service requests and is never concerned in the places of servers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD OF THE INVENTION The present invention generally relates to client /
It relates to a communication system between objects (that is, processes) between a client and a server in a server environment.
(Referred to as a distributed environment).

[0002]

2. Description of the Related Art Conventionally, communication between objects in a client / server environment uses a socket,
Various methods such as using C have been used. Traditionally, components or techniques for inter-object communication, whether sockets or RPCs, are originally applied to a client / server environment with local file access and function calls on a single machine. . In this conventional communication between objects, it is necessary for a client to always perform communication in consideration of a node in which a partner server object exists.

[0003]

In a distributed environment in which server objects are distributed to a plurality of nodes, if conventional inter-object communication is employed, there is a problem that a communication program of a client becomes complicated and difficult to construct. is there. That is, an advantage of the distributed environment is a load distribution function of a server (for example, when a certain server has a failure or a high load, another server performs a service instead).
However, if a program is written to support such functions, a plurality of nodes must be considered at the same time, and the description of the coping logic and the environment definition are inevitably complicated. Furthermore, it is difficult to flexibly respond to server changes and expansion.

In the conventional inter-object communication based on, for example, RPC, an original function call is applied to a client / server environment. However, a calling client object issues an RPC call and then issues a server object call. The process waits until the process is completed (that is, a synchronous process is performed). The reason for this is that it is not impossible to perform asynchronous processing by RPC, but this would make the logic very complicated. Furthermore, especially R
In a PC, the communication itself takes a considerable amount of time, so each time a client issues an RPC call, the client has a long time including the communication time for sending the call, the processing time in the server, and the communication time for returning the processing result. , Will be waiting.

Accordingly, an object of the present invention is to enable a client to perform inter-object communication in a distributed environment without being aware of a node where a server exists.

[0006] Another object of the present invention is to provide, in a distributed environment,
An object of the present invention is to enable a client to perform another process while a server performs a process requested by the client, that is, to enable asynchronous cooperative processing between objects.

[0007]

According to the present invention, a service agent for performing communication between a client and a server is provided on a communication network in which clients and servers are scattered. The service agent knows the location of the server, receives a service request issued by the client, communicates with the server in response to the request, causes the server to execute service processing, receives a service processing result from the server, Then, the service processing result is returned to the client. Therefore, the client
The problem of communication with the server is released, and it is not necessary to be aware of the location of the server. Therefore, it becomes very easy to build a client program, and it is possible to flexibly cope with a change or expansion of a server.

[0008] In a distributed environment, the service agent:
It is desirable to manage the location, status, and service name of each server. Thus, when a service request is received from a client, a server that can respond to the service request can be selected, and the selected server can be requested to execute a service process.

When the service agent returns a service processing result to the client, it is desirable that the client be called using a callback. This eliminates the need for the client to wait until a service processing result arrives after issuing a service request to the service agent. That is, asynchronous cooperative operation between objects becomes possible. From the same viewpoint, it is desirable that the service agent is configured to call the server using the callback even when the service agent requests the server to execute the service processing.

[0010] The service agent can have the following configuration, for example. First, the same node as the client receives a service request from the client,
A client interface for returning a service processing result to a client is provided. Also, a server interface for requesting the server to execute service processing and receiving service processing results from the server is provided in the same node as the server. Further, a predetermined node is provided with a service manager holding service information indicating the location, status, and service name of the server. Then, the client interface, the service manager, and the server interface communicate with each other and operate as a whole to realize the function of the service agent described above.

The specific operations of the client interface, service manager and server interface are as follows.
For example: First, the client interface sends an information inquiry request to the service manager in response to a service request from the client. In response to the information inquiry request, the service manager refers to the service information, selects a server that can respond to the service request, and notifies the client interface of the location of the selected server. The client interface is addressed to the location notified by the service manager,
Send service request. The server interface receives a service request from the client interface and requests the server to execute service processing. When the service processing in the server is completed, the server interface receives the service processing result from the server and returns it to the client interface. The client interface receives the service processing result and passes it to the client.

Preferably, the server interface notifies the service manager of the service name, location and status of the server at any time, and the service manager updates the service information according to the notification. Thus, the service information automatically becomes in accordance with the current state of the server.

A plurality of service agents may be provided on the same network. In this case, each service agent manages a different server (or a group of servers), and each service agent queries another service agent when a server that can respond to a service request from a client does not exist under its own umbrella, It can be configured to be taught a server that can respond to a service request. In this way, there is an advantage that the load of the service agent can be distributed when the number of servers is enormous. Also, for example, when a large number of servers are scattered around the world, by assigning a service agent for each area and managing servers in each area, priority is given to servers in an area close to the client's location. While still being able to access servers around the world as needed.

The program for causing a node (computer) on the network to function as the service manager, client interface or server interface described above is installed or installed on the computer through various media such as various disk storages, semiconductor memories, and communication networks. Can be loaded.

[0015]

FIG. 1 shows a system configuration of an embodiment of a communication system between objects in a client / server environment according to the present invention.

On a network, at least one client object (hereinafter, simply referred to as a client) 1, one or a plurality of object sets 3 and 7 called a "service agent", and a plurality of server objects (hereinafter simply referred to as a server). 5)
A, 5B, 5C,... (Collectively referred to as a server group 5), and one or more other server groups 9 are scattered.
The client 1 is in principle under the umbrella of one specific service agent 3. The server group 5 is, in principle, under the umbrella of one specific service agent 3, and similarly, another server group 9 is, in principle, under the umbrella of one other specific service agent 7. The location of each object in the network is specified by a node name indicating a node on the network and a process name indicating an object (process) in the node.

Although only one client 1 is shown in FIG. 1, in practice, many other clients usually exist on the same network. However, the description of one client 1 applies to the other clients as well, and illustration and description of the other clients are omitted.

The service agent 3 knows the service name, location and status of each of the servers 5A, 5B, 5C,... Another service agent 7 also manages the service name, location, and status of each server belonging to the server group 9 under its control. On the other hand, the client 1 has the number and location (node name, server name) of the servers 5A, 5B, 5C,.
The process name), status (current state such as idle, processing, failure, etc.) and the name of the service to be provided are not known at all.

The outline of the operation of each object is as follows.

Each of the servers 5A, 5B, 5C,... Informs the service agent 3 under its control at the start of the service of its own service name and location (node name and process name) (communication C1). The service agent 3 stores the service name and the location notified from each of the servers 5A, 5B, 5C,.
The statuses of B, 5C,... Are also monitored thereafter. Similarly, each server belonging to another server group 9 also notifies the service agent 7 of its service name and location (communication C2),
The service agent 7 manages it similarly.

The client 1 sends a service request specifying a service name to the service agent 3 (communication C).
3). The service agent 3 searches the server group 5 for a server that can respond to the service request, and sends the service request to the server (for example, the server 5B) (communication C).
4). The server 5B executes the processing of the requested service, and returns the processing result to the service agent 3 (communication C5). The service agent 3 sends the processing result to the client 1 (communication C6). In this communication C6, the service agent 3 calls the client 1 using a callback (CB) that has been taught from the client 1 in advance, and passes the processing result.

The service agent 3 can notify the client 1 when there is no server in the server group 5 that can respond to the service request from the client 1, but instead, another service agent can be used. 7 to the server (communication C
7). Another service agent 7 searches for a server that can respond to the request from the group of servers 9 under its control, and notifies the service agent 3 of the location of the server (communication C8).
The service agent 3 sends a service request to the notified server (communication C9), receives the result (communication C10), and sends it to the client 1 (communication C6).

As described above, the service agent 3 mediates the communication between the client 1 and the servers 5A, 5B, 5C,..., So that the client 1 can obtain information necessary for communication with the server (for example, the number of servers, The service can be provided simply by specifying the desired service name without knowing the location. That is,
The client 1 is released from the problem of communication with the server. This makes it very easy to construct a program for the client 1 without having to consider the circumstances of the server.

The service agent 3 communicates with the communication C
When returning the processing result to the client 1 in step 6, the predetermined CB
Is used to call the client 1. Therefore, the client 1 communicates with the communication C3 receiving the result from the communication C3 sending the request.
It is not necessary to wait all the way up to 6, and it is possible to shift to another process as soon as the communication C3 ends. That is, asynchronous cooperative operation between objects is possible.

FIG. 2 shows the structure and operation of the service agent 3 in more detail.

The service agent 3 is incorporated in each of the client 1 and the servers 5A, 5B,..., The service manager 31 provided as a daemon process of the service agent, the service table 33 which exists only in the service manager 31, and Attached service / application interface (Service A
PI) 35, 37A, 37B, 37C,... The service manager 31 includes service APIs 35 and 37
A, 37B,... Are located at nodes at a specific place known. Each of the service APIs 35, 37A, 37B,...
And servers 5A, 5B, 5C,...

The main functions of the service manager 31 are:
Manages the service names, node names, process names, and statuses (hereinafter, collectively referred to as service information) of all the servers 5A, 5B,... Under the umbrella on the service table 33, and receives a service request from the client 1. Server group 5 belonging to the umbrella with reference to the service table 33
That is, a server that can respond to the service request is searched from the server group 5 under its control.

Each service API 35, 37A, 37B,
The main functions of the service manager 3 are for the corresponding client 1 and servers 5A, 5B, 5C,.
1 and the communication with another server or client.

FIGS. 3 and 4 show the flow of operation of each object shown in FIG. FIG. 5 shows an example of the contents of the service table 31. Hereinafter, the operation of each unit will be described with reference to FIGS.

Each server 5A, 5B,... Sends a service provision declaration to each service API 37A, 37B,. The service provision declaration includes a service name for identifying the service processing of each server, and designation of a predetermined provided CB. Here, the provided CB refers to each server 5A, 5
, B,..., And by calling this, it is possible to cause each of the servers 5A, 5B,. When the service provision declaration is accepted by each of the service APIs 37A, 37B,..., A confirmation response to that effect is returned to each of the servers 5A, 5B,.

Each service API 37A, 37B,.
In response to the service provision declaration from each of the servers 5A, 5B,..., A service provision declaration including the service name, node name, and process name of each server is sent to the service manager 31 (communication C22).

The service manager 31 checks each service A
When the service provision declaration is received from the PIs 37A, 37B,..., The service name, the node name, and the process name included in the declaration are registered in the service table 33 (step S1). At the time of this registration, the service manager 31 sets the status on the table 33 indicating the status of the server to “idle”. Therefore, as illustrated in FIG. 5, the service names, node names, process names, and statuses of all the servers 5A, 5B,... That have already been started are recorded in the service table 33.

The client 1 has its own service API
A service request is sent to 35 (communication C23). The service request includes a service name for identifying the requested service, and designation of a predetermined response CB. Here, the response CB is a subject that receives the service processing result in the client 1, and by calling this, the client 1 can receive the service processing result. When the service request is accepted by the service API 35, a confirmation response to that effect is returned from the service API 35 to the client 1. After receiving this acknowledgment, if the result of the service processing comes, the service API 35 responds
Since B is called, the client 1 can shift to another process without waiting for the result of the service process.

When the service API 35 receives a service request from the client 1, the service API 35 uses the service name as a key and
The service information is inquired to the service manager 31 (communication C24).

The service manager 31 refers to the service table 33 to search for a server that can currently provide the service name (step S2). Specifically, a server whose service name on the table 33 matches the service name for the inquiry and whose status on the table 33 is “idle” is searched. If a server that satisfies this condition is found, the service manager 31 stores a node name indicating the location of the server and a process name in the table 33.
And returns it to the inquiry service API 35 (communication 25).

The service API 35 sends the service request including the service name requested by the client 1 to the node name and the process name received from the service manager 31 (for example, the server 3A) (communication C26). ).

Upon receiving the service request, the service API 37A of the server 3A calls the provided CB specified in advance by the server 3A (communication C27). Thereby, the service processing of the server 3A is started. When the service processing is started, the service API 37A sends a status change notification to the effect that the status is changed to “processing” to the service manager 31 (communication C28). This status change notification includes the node name and the process name of the server 3A. Upon receiving the status change notification, the service manager 31 changes the status on the service table 33 corresponding to the node name and the process name from "idle" to "processing" (step S).
3).

When the service processing is completed and the provided CB ends, the server 3A issues a declaration of the end of the provided CB to the service AP.
Send to I37A (communication C29). The end declaration includes the result of the executed service process (for example, a search result when a database search is performed).

Upon receiving the provision CB end declaration, the service API 37A sends a status change notification to the effect that the status is changed to "idle" to the service manager 31 (communication C30). Upon receiving the notification, the service manager 31 changes the corresponding status on the service table 33 from “processing” to “idle” (step S4).

A service API that has received a provision CB end declaration
37A further returns the service processing result to the client 1 of the service request source (communication C31). Upon receiving the service processing result, the service API 35 of the client 1 calls a response CB (communication C32).
Thereby, the client 1 receives the service processing result.

When the service manager 31 receives a service information inquiry from the service API 35 of the client 1 (communication C24) and finds no server satisfying the conditions from the service table 33, the service manager 31 shown in FIG.
As shown in (3), the same service information inquiry can be sent to the service manager of another service agent (communication C33). Then, the other service manager searches for a server that satisfies the condition from its own service table, and returns the node name and the process name to the service manager 31 that has made the inquiry (communication C34).
The service manager 31 sends the node name and the process name to the service API 35 of the client 1 (communication 25), and the service API 35 issues a service request with the node name and the process name as destinations (communication C35). Can be received (communication C36).

With the above-described specific configuration and operation, as described above with reference to FIG. 1, the client 1 does not need to be aware of the server and can perform asynchronous cooperative operation between objects. Benefits are obtained.

FIG. 6 shows an example of one specific advantage obtained by enabling asynchronous cooperative operation between objects.

For example, assume the following case. That is, the client 1 wants to perform a specific calculation as quickly as possible. There are two types of methods for performing the specific calculation, algorithms A and B, and which method is faster depends on the value of input data. The servers 5A, 5B, 5C,... That implement the algorithm A or B are scattered on the network, and there are multiple servers for each algorithm as illustrated.

In such a case, the client 1 can issue two service requests to the service agent 3 in succession, namely, a "calculation request by algorithm A" and a "calculation request by algorithm B" (communications C41, C42). ). This is because asynchronous processing is possible, so that one calculation request can be issued before one calculation is completed.

Then, the service agent 3 immediately finds a server whose status is idle for each of the algorithms A and B (for example, the server 5A and the server 5C), and requests them for a specific calculation. (Communications C43, C44). The server 5A and the server 5C perform calculations using the algorithms A and B, respectively, and the one that completes the calculation earlier (for example, the server 5A) returns the calculation result first (communication C45). Therefore, client 1
Can receive the faster calculation result without any effort (communication C46).

The embodiment of the present invention has been described above.
This embodiment is merely an example for describing the present invention,
The present invention can be implemented in another mode different from the configuration and operation described above.

For example, in the above embodiment, each client and each server are under the umbrella of one service agent, and communicate with only one service agent. However, this need not be the case, and a client or a server may be under the umbrella of two or more service agents. In that case, the service API of the client or the service API of the server needs to know the location of the service manager of two or more service agents under its umbrella. This makes it possible to distribute the load of the service manager. Also, for example, a certain service agent has a group of servers providing a certain type of service under its umbrella, and another service agent has a group of servers providing another specific type of service under its umbrella. In this case, it is possible to adopt a configuration in which one client who wants to receive both services falls under the umbrella of the two service agents and uses the service agent properly according to the desired service.

In the description of the above embodiment, the service API of the client or the server is described as a part of the service agent. However, this is only one method of description or conceptualization. Another explanation is possible. For example, the service API of each client or each server can be understood as a part of each client or each server instead of a part of the service agent, or the service API, the client, and the server can be understood by any of them. It can also be understood as an independent object that does not belong. Therefore, in interpreting the scope of the claims of the present invention, it is necessary to flexibly interpret the claims without being bound by one method of explanation or conceptualization.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

FIG. 2 is an exemplary block diagram showing a more specific configuration of the embodiment;

FIG. 3 is a sequence diagram showing the operation of the embodiment.

FIG. 4 is a sequence diagram showing the operation of the embodiment.

FIG. 5 is a diagram showing an example of a service table.

FIG. 6 is a view for explaining one advantage of the asynchronous cooperative operation between objects.

[Explanation of symbols]

1 Client (Client Object) 3, 7 Service Agent 5, 9 Server Group 5A, 5B, 5C Server (Server Object) 31 Service Manager 33 Service Table 35, 37A, 37B Service Application Interface

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hideaki Yamamoto 3-3-3 Toyosu, Koto-ku, Tokyo NTT Data Communications Co., Ltd. (72) Ryosuke Masuki Inventor Ryosuke Toyosu, Koto-ku, Tokyo 3-3-3 NTT Data Communication Co., Ltd. (72) Inventor Jun Uchikawa 1-3-2 Marunouchi, Chiyoda-ku, Tokyo Within Sumitomo Bank, Ltd. (72) Inventor Nobuhiko Ichiki Tokyo 1-3-2 Marunouchi, Chiyoda-ku Within Sumitomo Bank, Ltd.

Claims (29)

[Claims] 1. A communication network, a client for issuing a service request existing on the network, a server for executing service processing existing on the communication network, and existing on the communication network The server knows the location of the server, communicates with the server in response to a service request issued by the client, causes the server to execute the service processing, and causes the server to execute a service processing result. And a service agent for returning the service processing result to the client. 2. The server according to claim 1, wherein the plurality of servers are scattered on the network, the service agent has service information indicating a location, a status, and a service name of each of the servers. The system according to claim 1, wherein in response to the service request, a server capable of responding to the service request is selected by referring to the service information, and communicates with the selected server. 3. The method of claim 1, wherein the client has a response callback for receiving the service processing result, and wherein the service agent calls the response callback when returning the service processing result to the client. system. 4. The server according to claim 1, wherein said server has a predetermined providing callback for executing said service processing, and said service agent calls said providing callback when requesting said server to execute said service processing. Item 4. The system according to any one of Items 1 and 3. 5. A client interface arranged on the same node as the client, for receiving the service request from the client and returning the service processing result to the client, a location and a status of the server. A service manager arranged at a predetermined node, having service information indicating a service name and a service name; and the server for sending an execution request of the service processing to the server and receiving the service processing result from the server. And a server interface located on the same node as the client interface, wherein the client interface, service manager, and server interface communicate over the communication network. 6. The client interface sends an information inquiry request to the service manager in response to the service request from the client, and the service manager sends the service information in response to the information inquiry request. Selecting a server capable of responding to the service request by reference, notifying a location of the selected server to the client interface, wherein the client interface sends the service request addressed to the location notified by the service manager. Receiving the service request from the client interface, requesting the server to execute service processing, receiving the service processing result from the server, and transmitting the service processing result to the service request. From 6. The system according to claim 5, wherein the client interface receives the service processing result from the server interface and passes it to the client. 7. The server interface notifies the service manager of the service name, location, and status of the server, and the service manager updates the service information in response to the notification from the server interface. The system according to claim 5. 8. The method according to claim 5, wherein the client has a response callback for receiving the service processing result, and the client interface calls the response callback when returning the service processing result to the client. system. 9. The server according to claim 1, wherein said server has a predetermined providing callback for executing said service processing, and said server interface calls said providing callback when said server interface requests said server to execute said service processing. Item 9. The system according to any one of Items 5 and 8. 10. The server further comprising: another server existing on the communication network; and another service agent existing on the communication network, the service agent knowing a location of the another server. When notified of the location of the another server from another service agent, the server communicates with the another server, requests the another server to execute service processing, and receives a service processing result from the another server. 2. The system according to claim 1, wherein the service processing result can be returned to the client. 11. A communication network in which a client for issuing a service request and a server for performing service processing are present on a communication network, and the location of the server is known, and a response to a service request issued by the client is provided. And communicating with the server to cause the server to execute the service processing, receive a service processing result from the server, and return the service processing result to the client. Service agent for communication. 12. The server has service information indicating a location, a status, and a service name of each of the plurality of servers scattered on the network, and receives the service information in response to the service request from the client. To select a server that can respond to the service request,
The service agent of claim 11, wherein the service agent communicates with a selected server. 13. The service agent according to claim 11, wherein when returning the service processing result to the client, a predetermined response callback for receiving the service processing result held by the client is called. 14. A server according to claim 11, wherein when the server requests the server to execute the service processing, a predetermined provision callback for executing the service processing included in the server is called. The stated service agent. 15. A client interface arranged on the same node as the client for receiving the service request from the client and returning the service processing result to the client, and indicates a location, status, and service name of the server. A service manager, which has service information and is arranged at a predetermined node; and is arranged at the same node as the server, for sending an execution request for the service processing to the server and receiving the service processing result from the server. The service agent according to claim 11, further comprising a server interface configured to communicate with the client interface, the service manager, and the server interface through the communication network. 16. The client interface,
In response to the service request from the client,
Requesting an information inquiry from the service manager, the service manager responding to the information inquiry,
Selecting a server capable of responding to the service request with reference to the service information, and notifying the location of the selected server to the client interface, wherein the client interface is addressed to a location notified by the service manager; Sending a service request, the server interface receiving the service request from the client interface, requesting the server to execute service processing, and receiving the service processing result from the server, The service agent according to claim 15, wherein the client interface receives the service processing result from the server interface and passes the result to the client. 17. The server interface notifies the service name, location, and status of the server to the service manager, and the service manager updates the service information in response to the notification from the server interface. The service agent according to claim 15. 18. When another service agent existing on the communication network is notified of the location of another server on the communication network, the server communicates with the other server and performs service processing on the another server. 12. The service agent according to claim 11, wherein the service agent can request execution of the service processing, receive a service processing result from the another server, and return the service processing result to the client. 19. A service which is arranged at a predetermined node on a communication network in which a client for issuing a service request and a server for executing service processing are scattered, and indicates a location, a status, and a service name of the server. In response to an information inquiry from the client side, selecting a server capable of responding to the service request of the client by referring to the service information, and transmitting the location of the selected server to the client side Notify the service manager for inter-object communication in the client / server environment. 20. The service manager according to claim 19, wherein the service information is notified from the server side, and the service information is updated, and the service information is updated. 21. In response to the request from the client side, querying another service manager existing on the communication network for a location of another server capable of responding to the service request, 20. The service manager according to claim 19, wherein the location of the another server notified from the server can be notified to the client side. 22. A node on a communication network in which a client for issuing a service request and a server for executing service processing are scattered, and service information indicating the location, status, and service name of the server is provided. Holding, in response to an inquiry from the client side, selecting a server capable of responding to the service request of the client by referring to the service information, and notifying the client side of the location of the selected server; A computer-readable recording medium carrying a computer program for functioning as a service manager for inter-object communication in a client / server environment. 23. selecting a client for issuing a service request, a server for executing service processing, and a server capable of responding to the service request of the client in response to an information inquiry from the client side;
A service manager for notifying the client side of the location of the selected server is located on the same node as the client on a communication network in which the service manager is scattered, and in response to the service request issued by the client, Sending an information inquiry to the service manager, receiving a notification of the location of the selected server from the service manager, sending the service request to the notified location, receiving the service processing result from the server side, A client interface for inter-object communication in a client / server environment. 24. The client interface according to claim 23, wherein when returning the service processing result to the client, a predetermined response callback for receiving the service processing result held by the client is called. 25. selecting a client for issuing a service request, a server for executing service processing, and a server capable of responding to the service request of the client in response to an information inquiry from the client side;
In response to the service request issued by the client, the information inquiry is performed on the same node as the client on a communication network in which a service manager that notifies the client of the location of the selected server is scattered. To the service manager, receiving the notification of the location of the selected server from the service manager, sending the service request addressed to the notified location, receiving the service processing result from the server side, A computer-readable recording medium carrying a computer program for functioning as a client interface for inter-object communication in a client / server environment. 26. Selecting a client for issuing a service request, a server for executing service processing, and a server capable of responding to the service request of the client in response to an information inquiry from the client side;
A service manager for notifying the client side of the location of the selected server is located on the same node as the server on a communication network in which the service request is sent from the client side. A server interface for inter-object communication in a client / server environment, for requesting a server to execute a service process, receiving the service process result from the server, and returning the service process result to the client side. 27. The server interface according to claim 26, wherein when requesting the server to execute the service processing, a predetermined provided callback for executing the service processing of the server is called. 28. The service manager is notified of the service name, location and status of the server.
The described server interface. 29. selecting a client for issuing a service request, a server for executing service processing, and a server capable of responding to the service request of the client in response to an information inquiry from the client side;
The same node as the server on the communication network in which the service manager notifying the location of the selected server to the client side is scattered, upon receiving the service request sent from the client side, A computer for requesting execution of service processing, receiving the service processing result from the server, and returning the service processing result to the client side, and functioning as a server interface for inter-object communication in a client / server environment. A computer-readable recording medium carrying a program.