JPH10154980A - Ip multi-cast service system and its address assignment method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To process dynamically internet protocol(IP) multi-cast address assignment/release processing in the IP multi-cast service. SOLUTION: An IP multi-cast address management section 1 placed in a network 2 manages IP multi-cast addresses used in the IP multi-cast service and has a means that assigns/releases the IP multi-cast address. The assignment/ release of the IP multi-cast service is conducted between transmission hosts 11-13 and the IP multi-cast address management section 1 via the network 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to data communication between a plurality of computers and a host, and more particularly to a multicast communication service at an IP level, and which acquires and releases an IP multicast address used in a service online. On how to do it.

[0002]

2. Description of the Related Art A service operator who hosts and starts an IP multicast service needs to obtain an IP multicast address in advance. In order to obtain an IP multicast address, there is a management organization that centrally manages the IP multicast address. The management organization makes a document application to obtain the IP multicast address.・ Determine the address assignment and notify the service operator by document. The service operator can start the IP multicast service using the IP multicast address acquired by this notification.

[0003] The same procedure is used when returning (opening) an IP multicast address that is no longer needed after terminating the service.

[0004] Prior arts related to the present invention have been proposed. For example, Japanese Unexamined Patent Publication No. Hei 8-163156 discloses a "multicast communication system" that enables continuous multicast communication even when a terminal moves.
Is disclosed. In Prior Art 1, each terminal has a correspondence table between a unique address of a multicast group to which each terminal belongs and a position address. That is, each terminal has a correspondence table that associates a unique address corresponding to a group to which the terminal belongs with a position address in a connected network. The relay device has a correspondence table between a unique address related to a multicast group passing through the connected sub-network and a position address. The location address is repeatedly used for effective use of the address, and is defined for each subnetwork. Each relay device
The packet is relayed by associating the sub-network with the unique address.

[0005]

[Problems to be Solved by the Invention]
The service is characterized in that most of the services are temporary services, and in order to effectively use the IP multicast address, the acquisition of the IP multicast address is performed before the service is started, and after the service is terminated. Is used to be released. Therefore, it is troublesome to perform this procedure, which is performed every time the operation of the service is started / finished, by human means by applying for documents. Therefore, in order to simplify the procedure, it is desirable that the operation start / end of the service be automated as much as possible and processed in a short time.

[0006] Further, as the number of holdings of the IP multicast service increases, the processing load on the management organization also increases, and it is necessary to perform these processes more dynamically and accurately. However, at present, this process is performed by human means,
There is a problem that it is difficult to realize it.

Therefore, the technical problem of the present invention is to
An object of the present invention is to dynamically allocate / release an IP multicast address in a multicast service.

[0008] The prior art only discloses a technical idea that enables continuous multicast communication even when a terminal moves, and dynamically processes IP multicast address allocation / release. This is different from the technical idea of the present invention.

[0009]

The present invention has the following means to solve the above-mentioned problems.

[0010] A plurality of sending hosts capable of transmitting IP multicast packets, a plurality of receiving hosts capable of receiving IP multicast packets, and an IP multicast address used in the IP multicast service system And an IP multicast address management unit including means for allocating and releasing an IP multicast address. A plurality of hosts, a plurality of reception hosts, and an IP multicast address management unit Assignment and release of an IP multicast address used in an IP multicast service between a sending host and an IP multicast address management unit in an environment where the IP multicast address can be interconnected via a network capable of performing a service. Ne Performed via the network.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows an IP multicast service system according to an embodiment of the present invention. The illustrated IP multicast service system includes first to third transmission hosts 11, 12, 13, first to third reception hosts 21, 22, 23, an IP multicast address management unit 1, and And a network 2 to be connected. The illustrated example shows an example in which there are three transmission hosts and three reception hosts, but the number is not limited to three.

IP multicast address management unit 1
Generates and manages the operation status of all the IP multicast addresses available in a certain domain (network) 2 on a database 51 shown in FIG. IP multicast address management unit 1
Performs automatic assignment / release of an IP multicast address by exchanging messages with each host in the domain 2.

The network 2 has an IP multicast
In a network capable of providing a service, in practice, as shown in FIG. 2, a plurality of routers 41 are interconnected by a dedicated line or the like between hosts.

The first to third transmission hosts 11 to 13
A host that can perform (transmit an IP multicast packet) with a certain IP multicast service.

The first to third receiving hosts 21 to 23
A host that can receive an IP multicast packet transmitted by an IP multicast service.

The IP multicast address management unit 1
The first to third transmission hosts 11 to 13 and the first to third reception hosts 21 to 23 can be connected via the network 2.

FIG. 3 is a block diagram for explaining address assignment processing, and FIG. 7 is an operation sequence diagram showing the operation. FIG. 4 is a block diagram for explaining the address release processing, and FIG. 8 is an operation sequence diagram showing the operation. FIG. 5 is a block diagram for explaining the address collecting process, and FIG. 9 is an operation sequence diagram showing the operation.

FIG. 6 is a diagram showing a database 51 generated and held by the IP multicast address management unit 1. The database 51 stores an address 52 and a usage state 5
3, a user name 54, and a user address 55. The address 52 indicates the target IP multicast address, the usage status 53 indicates whether the address is currently in use, the user name 54 indicates the name of the user using the address 52, and the user address Reference numeral 55 indicates the IP address of the user.

Next, referring to FIG. 3, FIG. 6 and FIG.
The address assignment processing will be described.

The user of the first transmission host 11 who wants to start the IP multicast service receives an address acquisition request 3 from the IP multicast address management unit 1 in order to acquire an IP multicast address to be used.
Send 1 The user name is set in the address acquisition request 31. The address acquisition request 31 is a message transmitted as an IP unicast packet.
The P address is set. The user needs to know the IP address of the IP multicast address management unit 1 in advance. Once the address acquisition request 31 is transmitted to the network 2, it is forwarded to the destination by each relay router 41 (FIG. 2) in the network 2. Hereinafter, the same applies to other messages to be described.

IP multicast address management unit 1
Uses the reception of the address acquisition request 31 as a trigger to detect and assign an unused IP multicast address from the database 51. The IP multicast address management unit 1 sends the I
The P multicast address is set in the address acquisition response 32 and transmitted to the transmission host 11. At the same time, the IP multicast address management unit 1 updates each information related to the newly assigned IP multicast address in the database 51 as follows. Usage situation 5
3 is changed from “unused” to “in use”. The user name set in the address acquisition request 31 is set as the user name 54. The source address of the address acquisition request 31 is set in the user address 55.

The first sending host 11 starts the IP multicast service using the IP multicast address set in the received address acquisition response 32.

Next, referring to FIG. 4, FIG. 6 and FIG.
The address release processing will be described.

Ending the IP multicast service,
The user of the sending host 11 who wants to release (return) the used IP multicast address needs to release the used IP multicast address.
An address release request 33 is transmitted to the IP multicast address management unit 1. In the address release request 33, the user name and the IP multicast address used are set.

IP multicast address management unit 1
Detects whether the specified IP multicast address is in use from the database 51 by using the reception of the address release request 33 as a trigger, and decides to release the IP multicast address if it is in use. After releasing the IP multicast address, the IP multicast address management unit 1 transmits an address release response 34 to the first transmission host 11 to notify that the address has been released. At the same time, the IP multicast address management unit 1
Updates the information related to the released IP multicast address in the database 51 as follows. The use status 53 is changed from “in use” to “unused”. The set user name is deleted from the user name 54. Then, the set address is deleted from the user address 55.

The first transmission host 11 confirms that the address has been released by the received address release 34.

Next, an address collection process will be described with reference to FIGS.

When the IP multicast address management unit 1 periodically checks whether or not the contents of the database 51 and the state at each transmission host match, or when the IP multicast address management unit 1 fails for some reason, When the information in the database 51 is lost and recovery is performed, the IP multicast address management unit 1 collects information from each transmission host.

IP multicast address management unit 1
Sends an address collection request 35 to each sending host. Note that, unlike other messages, the address collection request 35 must be transmitted to all hosts, and is therefore a broadcast packet. Therefore, all the hosts connected to the network 2 receive the address acquisition request 35.

If the host that has received the address collection request 35, for example, the first transmission host 11, uses an IP multicast address, it sends an address collection response 37 to the IP multicast address management unit 1. . The address collection response 37 includes, in addition to the user name,
Turn on the flag indicating use / unuse (logic "1" level:
In use) and the IP multicast address in use. Note that the address collection response 37 is a unicast packet.

A host that does not use the IP multicast address, for example, the second host 12, also sends an address collection response 36. At this time, in the address collection response 36, in addition to the user name, a flag indicating use / unused is set to off (logic "0" level: unused).
The field for setting the IP multicast address is blank.

IP multicast address management unit 1
Performs collation with the database 51 based on the received plurality of address collection responses, and performs updating and the like as necessary.

The present invention is not limited to the above-described embodiment, and various changes and modifications can be made without departing from the spirit of the present invention.

[0035]

As described above, according to the present invention, an IP multicast address management unit is arranged in a domain (network) so as to be connectable to each host via the network, and is used in the domain. All I
The P multicast address is managed in a unified manner, and it is possible to allocate / release an IP multicast address by exchanging with a host via a network. Thus, the user who wants to start the IP multicast service can be assigned an IP multicast address and the user who ends the IP multicast service can be performed without performing a time-consuming application process for acquiring the IP multicast address to the management organization. Release of the IP multicast address from the server can be dynamically processed. Furthermore, there is an effect that it is possible to cope with a case where the demand for the IP multicast service is expanded and the number of IP multicast addresses to be managed is increased.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an IP multicast service system according to an embodiment of the present invention.

FIG. 2 is a block diagram showing an additional connection in a network in the IP multicast service system shown in FIG. 1;

FIG. 3 is a block diagram for explaining an address assignment process in the IP multicast service system shown in FIG. 1;

FIG. 4 is a block diagram for explaining an address release process in the IP multicast service system shown in FIG. 1;

FIG. 5 is a block diagram for explaining address collection processing in the IP multicast service system shown in FIG. 1;

FIG. 6 is a diagram showing a database held by an IP multicast address management unit of the IP multicast service system shown in FIG. 1;

FIG. 7 is an operation sequence showing an operation of an address assignment process in the IP multicast service system shown in FIG. 1;

FIG. 8 is an operation sequence showing an operation of an address release process in the IP multicast service system shown in FIG. 1;

FIG. 9 is an operation sequence showing an operation of an address collection process in the IP multicast service system shown in FIG. 1;

[Explanation of symbols]

 Reference Signs List 1 IP multicast address management unit 2 Network (domain) 11, 12, 13 Sending host 21, 22, 23 Receiving host 31 Address acquisition request 32 Address acquisition response 33 Address release request 34 Address release response 35 Address collection request 36, 37, 38 Address Collection Response 41 Router 51 Database 52 Address (IP Multicast Address) 53 Usage 54 User Name 55 User Address

Claims (4)

[Claims] In an IP multicast service system for performing an IP (Internet Protocol) level multicast communication service in data communication between computers, a plurality of transmission hosts capable of transmitting IP multicast packets are provided. A plurality of receiving hosts capable of receiving the IP multicast packet, and means for managing an IP multicast address used in the IP multicast service system, and allocating and releasing the IP multicast address. An IP multicast service system, comprising: an IP multicast address management unit. 2. The IP multicast according to claim 1,
A method of allocating addresses in a service system, wherein the plurality of sending hosts, the plurality of receiving hosts, and the IP multicast address management unit mutually communicate via a network capable of performing the IP multicast service. In an environment where connection is possible, allocation and release of the IP multicast address used in the IP multicast service are performed between the transmission host and the IP multicast address management unit via the network. Address allocation method in an IP multicast service system. 3. The transmission host transmits a required IP multicast address to the IP multicast address management unit via the network prior to the start of the IP multicast service. Steps: after terminating the IP multicast service, in order to release (return) the used IP multicast address, issue an address release request to the IP multicast address management unit via the network. Transmitting.
3. An address assignment method in the IP multicast service system according to item 1. 4. The method according to claim 1, wherein the IP multicast management unit holds and updates information including an IP multicast address that can be used in the network and a use status, and responds to the address acquisition request from the transmission host. Assigning an unused IP multicast address, notifying the transmission software in response to the address acquisition, updating the held information, and releasing the address from the transmission host. Releasing the in-use IP multicast address specified by the transmitting host in response to the request, notifying the request by responding to the transmitting host as an address release response, and updating the held information. Claim 3 characterized by the following:
3. An address assignment method in the IP multicast service system according to item 1.