JPH08297648A - Multicast communication processor - Google Patents

Abstract

PURPOSE: To facilitate multicast type data communication processing. CONSTITUTION: When mutually exchanging the same data between the plural processes operated on plural computers 11 and 12, multicast communication objects 41, 42 and 43 having the same name (object name) are previously generated on respective processes 31, 32 and 33. The procedure of data exchange is performed by issuing the request of transmission/reception to these multicast communication objects 41, 42 and 43. When the data transmission request is received from the process 32, for example, the multicast communication object 42 requests processing to a multicast communication managing server 3. Then, the multicast communication managing server 3 transmits the data to the processes 31 and 33 owning the multicast communication objects 41 and 43 to be objects. Concerning the reception of data, it is also performed by issuing the reception requests from the processes 31 and 33 to the multicast communication objects 41 and 43.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to a case where a plurality of processes on a plurality of computers, which are connected to each other via a network, exchange data simultaneously by multicast type communication and cooperate with each other. The present invention relates to the multicast communication processing device.

[0002]

2. Description of the Related Art Multicast communication means that a process sends the same data to a plurality of other specific processes. When data exchange is performed between processes on a plurality of computers connected via a network and between processes on a certain computer, TCP / TCP is conventionally used.
Communication protocols called IP and UDP / IP are used. The TCP / IP method is a data exchange method called Transmission Control Protocol / Internet Protocol. The UDP / IP method is a data exchange method called a user datagram program / Internet protocol. To exchange data between different processes using these protocols, for example, a mechanism called a socket is used. Two
When exchanging data between two processes, one process opens a socket and the other process issues a bind request to the socket. Then, after the coupling is completed, processing such as data transmission / reception is started. Such a technique has been put to practical use as a basic function of network communication in a conventional computer operating system (for example, "UNIX network programming:
W. See Richard Stevens / Yo Shinoda-Translation, Toppan ”).

[0003]

However, the above-mentioned conventional techniques have the following problems. That is, when a certain process P1 sends data to a plurality of other processes P2 and P3 by multicast communication, first, the process P1 opens a socket. Then, other processes including the process P2 and the process P3 are coupled to this socket. After that, the process P1 had to detect the two addresses of the process P2 and the process P3 connected to the socket and specify both addresses to perform the data transmission process. Further, when the process (for example, the process 3) connected to the socket is released, there is a restriction that the data transmission process should not be executed for the process 3. In other words, in order to perform multicast-type communication using the socket mechanism, it is necessary for the program creator to be responsible for determining all of the multicast target processes. As described above, in the multicast type communication, the designation of the data transmission destination is troublesome, and it is very difficult to create the program.

[0004]

The multicast communication processing device of the present invention is characterized by the following points in order to solve the above-mentioned problems. (1) That is, a plurality of processes operating on any computer in a computer environment connected to each other via a network perform data exchange (distribution) by multicast communication. In this case, it is assumed that a multicast communication object can be set for a process for exchanging data by multicast communication, and that multicast communication data exchange can be performed between processes having the same name of the multicast communication object. On the other hand, a multicast communication management server for managing a multicast communication object is provided on an arbitrary computer among a plurality of computers connected by a network, and the multicast communication management server distributes data to a plurality of processes.

(2) In (1), a multicast communication management server and a communication process management server for mediating each process are provided on all computers, and when the process disappears, the multicast communication management server is notified. I do. As a result, the disappeared process is deleted from the target of the multicast communication, and the multicast communication is performed in which no failure such as data transmission to the nonexistent process occurs.

[0006]

[Action]

(1) When exchanging the same data among a plurality of processes operating on a plurality of computers, a multicast communication object having the same name (object name) is generated in advance on each process. The data exchange procedure is performed by issuing a transmission / reception request to this multicast communication object. Upon receiving the data transmission request, the multicast communication object requests the multicast communication management server for communication processing. Then, the multicast communication management server transmits data to the process that owns the target multicast communication object. Data reception is also performed by the receiving process by issuing a reception request to the multicast communication object. Thus, the multicast type data communication process is realized by the multicast communication management server, the communication process management server, and the multicast communication object. As a result, the program creator can write a transmission processing program for the multicast communication object owned by the own process without paying attention to the process that is the target of the multicast communication when transmitting data. Communication processing can be easily realized.

(2) In (1), when the process disappears or the like, the communication process management server on each computer notifies the multicast communication management server that the sender process is aware of the receiver process disappearance. Without doing
It is possible to describe a transmission processing program for a multicast communication object owned by the own process, and it is possible to realize a multicast type data communication processing more easily.

[0008]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a multicast communication processing device of the present invention. The illustrated apparatus includes communication process management servers 1 and 2 and a multicast communication management server 3.

The communication process management servers 1 and 2 have a plurality of computers, for example, two computers 11 and 12 in this embodiment.
It is provided in each. The computers 11 and 12 are mutually connected by the network 10. Each computer has an arbitrary number of processes 31 and 32, 3 respectively.
3 and multicast communication objects 41, 42 and 43 for performing multicast type communication between them. In each of the computers 11 and 12, the communication process management server 1 manages the multicast communication object 41, and the communication process management server 2 manages the multicast communication objects 42 and 43.

The multicast communication management server 3 is connected to the network 10 and serves as an overall management server for multicast data communication. That is, the multicast communication management server 3 manages all data communication, and the data transmission request issued to a certain multicast communication object is transmitted by the multicast communication management server 3. It also manages data distribution to the process that owns the multicast communication object with the same name as the multicast communication object. Such a multicast communication management server 3 includes computers 11, 12
It may be provided inside any of the above.

FIG. 2 shows an explanatory diagram of preprocessing until the start of the multicast type communication processing. First, in FIG. 2, it is assumed that the process 31 generates the multicast communication object 41 when performing data exchange by multicast type communication. In this case, as a process in the generated multicast communication object, the communication process management server 1 is notified of the object name and the process ID indicating the owner of the object. Further, the communication process management server 1 notifies the multicast communication management server 3 of the information and puts it under the control of the multicast communication management server 3. As a result, the multicast communication object 41 is identified on the network.

On the other hand, when the process 32 performs data communication with the process 31 by multicast type communication, the process 32 has the same name as the object name of the multicast communication object 41.
Generates 2. In this case, the object name of the multicast communication object 41 is notified from the multicast communication management server 3 to each process 32, 33 via the communication process management server 2.

As the processing in the generated multicast communication object 42, the object name and
The process ID of the process 32 that is the owner of the object is notified to the communication process management server 2. Then, the communication process management server 2 notifies the multicast communication management server 3 of the information. In this case, the name of the multicast communication object is already process 31.
The multicast communication management server detects that the multicast communication objects 41 and 42 are registered by, and groups the multicast communication objects 41 and 42. The processes 31 and 32 are now ready for multicast communication. Information is transmitted to the multicast communication object 42 in the opposite direction to the above route.

Further, when the process 33 also participates in the multicast communication, the process 33 executes the same processing as above. As a result, in the multicast communication management server 3, the processes 31, 32, and 33 are grouped as a process group for performing multicast communication. When the above-described preprocessing is completed and a group of processes performing multicast communication is determined, data communication by multicast communication is started between a plurality of processes belonging to the group.

FIG. 3 is an explanatory diagram of the concept of multicast communication. As shown in FIG. 3, it is assumed that the process 32 is a data transmission process and the processes 31 and 33 are data reception processes. In this case, the process 32 issues a data transmission request to the multicast communication object 42. The process 31 issues a data reception request to the multicast communication object 41 and the process 33 issues a data reception request to the multicast communication object 43. As a result, the data transmission request from the process 32 is notified to the multicast communication management server 3. Then, the transmission data is sent to the multicast communication objects 41 and 43 managed as multicast targets by the multicast communication management server 3. On the other hand, the multicast communication objects 41 and 43 can receive the transmission signal from the multicast communication management server and receive the data transmitted from the process 32.

When a process participating in multicast communication disappears, the process is deleted from the multicast communication target by the multicast communication management server 3. FIG. 4 is an explanatory diagram of post-processing when the process disappears. First, in FIG. 4, it is assumed that the process 33 disappears. In this case, the disappearance event of process 33 is
The communication process management server 2 is notified. Then, the communication process management server 2 notifies the multicast communication management server 3 that the multicast communication object 43 owned by the process 33 no longer exists. Based on this information, the multicast communication management server 3 changes the group of multicast communication to the multicast communication objects 41 and 42. As a result, the multicast communication after the disappearance of the process 33 becomes
And only 32 will be able to proceed.

In this way, the load on the program creation side can be reduced, and the creation of the multicast communication processing program can be made very simple. Further, even when the process group to be subjected to the multicast communication changes due to the generation / deletion of the process, the program on the data transmission side can be used without changing, so the program creator can also perform exceptional processing such as error processing. No need to describe. Accordingly, it becomes possible to develop a high quality program. It should be noted that the present invention is not limited to the above-mentioned embodiments, and can be variously modified. For example, in FIG. 1, the multicast communication management server 3 is a separate entity, but the computer 1
When it is provided inside either one of 1 and 12, it may be integrated with the communication process management server 1 or 2.

[0018]

As described above, according to the multicast communication processing apparatus of the present invention, a plurality of processes operating on any one of a plurality of computers connected to each other via a network are multicast. When exchanging data by type communication, a multicast communication object is provided in each process and data is sent and received to and from the multicast communication management server via that object, thus reducing the load on the program creator side. Therefore, it is possible to make the program of the multicast communication processing very easy.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of a multicast communication processing device of the present invention.

FIG. 2 is an explanatory diagram of preprocessing until the start of communication processing.

FIG. 3 is an explanatory diagram of a concept of multicast communication.

FIG. 4 is an explanatory diagram of post-processing when a process disappears.

[Explanation of symbols]

 1, 2 Communication process management server 3 Multicast communication management server 41, 42, 43 Multicast communication object

Claims (2)

[Claims] 1. A communication system in which a process operating on any one of a plurality of computers connected via a network transmits the same data to a plurality of other processes, one for a multicast transmission request of a certain process. Management of data communication by a communication process management server that specifies a name and creates a multicast communication object that performs broadcast communication between each process in all processes in the system and a multicast communication object created by the communication process management server And a multicast communication management server for performing the same. 2. The communication process management server, when the process disappears, issues a request for stopping data transmission to a multicast communication object in the process to the multicast communication management server, and the multicast communication management The multicast communication processing device according to claim 1, wherein the server stops data transmission to the multicast communication object.