JP3705427B2 - Data distribution system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a data distribution system for distributing multicast data transferred from a data transfer device on a network to a wireless terminal device via a wireless base station device.
[0002]
[Prior art]
A conventional data distribution system is configured by connecting a plurality of wireless terminal devices, wireless base station devices, data transfer devices, servers, and the like via a network. In the data distribution system, the wireless terminal device receives multicast data from the server by transmitting a reception start message to the data transfer device.
When a wireless terminal device receives multicast data, the wireless terminal device itself performs transmission / reception processing of a reception start message, an inquiry message, a report message, and a reception stop message related to the transfer control of each multicast data with the data transfer device. . The radio base station apparatus does not perform transmission / reception processing of these messages.
[0003]
FIG. 10 shows a conventional flow of multicast data distribution start / continuation / stop.
A typical example of the prior art is seen when a wireless terminal device receives IP multicast data via a wireless base station device. In IP multicast, a router connected to a radio base station apparatus corresponds to the data transfer apparatus. The router manages the presence / absence of a device that receives each multicast data using an IGMP (Internet Group Management Protocol) message. The IGMP message has the functions of the above reception start message, inquiry message, report message, and reception stop message. The IGMP message is transmitted and received between the wireless terminal device that receives the multicast data and the router. An explanation of the IGMP message is described in IETF (Internet Engineering Task Force), RFC 2236, “Internet Group Management Protocol, Version 2” and the like. Hereinafter, each process will be described.
[0004]
{Circle around (1)} When a device belonging to a network under a data transfer device (router) starts receiving multicast data, it transmits an IGMP Report to the router. If the router does not transfer the multicast data to the subordinate network, transfer is started.
This corresponds to the case of the invention of claim 1. In the prior art, a wireless terminal device that receives multicast data generates a reception start message and transmits the reception start message directly to the data transfer device. The data transfer device starts transfer when the multicast data is not transferred.
[0005]
{Circle around (2)} The data transfer device (router) transmits an IGMP Query in order to confirm whether there is a device receiving multicast data in the subordinate network. The IGMP Query includes a general query for all multicast data and a group-specific query for specific multicast data. The device that receives the multicast data transmits an IGMP Report corresponding to each received multicast data to the data transfer device. For General Query, an IGMP Report of all received multicast data is transmitted, and for Group-Specific Query, an IGMP Report is transmitted for designated multicast data. Thereby, the data transfer apparatus can confirm the presence or absence of the apparatus which has received about each multicast data. For each multicast data, the transfer is continued if the IGMP Report is received, and the transfer is stopped if the IGMP Report is not received.
This corresponds to the cases of claims 2 and 3 above. In the prior art, an inquiry message is transmitted from the data transfer device to the wireless terminal device, and the wireless terminal device generates a report message for the multicast data being received and transmits the report message to the data transfer device. The transfer device continues to transfer the multicast data. Multicast data for which no report message is received from any wireless terminal device stops forwarding.
[0006]
{Circle around (3)} When an apparatus belonging to the network under the data transfer apparatus (router) stops receiving certain multicast data, it transmits IGMP Leave. Upon receiving this, the router transmits a group-specific query of the multicast data to the subordinate network, and confirms whether there is another device receiving the multicast data. If the IGMP report of the multicast data is not received, the router stops forwarding.
This corresponds to the case of claim 4 described above. In the prior art, the wireless terminal device generates a multicast data reception stop message for stopping reception and directly transmits it to the data transfer device. At this time, if it can be confirmed that there is no other wireless terminal device that is receiving the multicast data in the network under the control of the data transfer device, the transfer is stopped.
[0007]
[Problems to be solved by the invention]
In the conventional method, a wireless terminal device that receives multicast data needs to transmit a reception start message, a report message, and a reception stop message to the data transfer device in order to control multicast data transfer. For this reason, it is necessary for all wireless terminal apparatuses to set up an uplink with the wireless base station apparatus. In this case, in a system in which the number of uplinks that can be set per radio base station apparatus is limited, the number of radio terminal apparatuses that can receive multicast data is limited. For this reason, the number of wireless terminal devices that can receive the same multicast data in the wireless section is limited, and wireless resources cannot be effectively used.
An object of the present invention is to provide a data distribution system that solves the problem of the prior art that it is necessary to set up an uplink from a wireless terminal device in order to transmit a reception start message, a report message, and a reception stop message to a data transfer device. Is to provide.
[0008]
[Means for Solving the Problems]
In the present invention, the above-mentioned problem is solved by transmitting / receiving a reception start message / inquiry message / report message / reception stop message to / from a data transfer apparatus by a radio base station apparatus instead of a radio terminal apparatus.
Hereinafter, each process will be described.
[0009]
In the first aspect of the invention, first, when the wireless terminal device starts receiving multicast data, the distribution setting device transmits a multicast data distribution start request message to the wireless base station device. Upon receiving this message, the radio base station apparatus generates a reception start message for the multicast data and transmits it to the data transfer apparatus. When the data transfer device receives this, if the multicast data is not being transferred to the subordinate network, the data transfer device starts the transfer, the wireless base station device starts the distribution, and the wireless terminal device can receive the multicast data. As a result, the radio terminal apparatus under the radio base station apparatus can start receiving multicast data without using the uplink.
[0010]
In the invention according to claim 2, when the data transfer apparatus transmits an inquiry message to the subordinate network to confirm the presence / absence of the apparatus receiving each multicast data, the radio base station apparatus It works as follows. First, when the inquiry message designates multicast data, if the designated multicast data is being distributed from the radio base station apparatus, a report message for the multicast data is generated and transmitted to the data transfer apparatus. When the inquiry message covers all multicast data, a report message of all multicast data being transmitted by the radio base station apparatus is generated and transmitted to the data transfer apparatus. When the data transfer apparatus receives a certain multicast data report message, the data transfer apparatus determines that there is an apparatus receiving the multicast data in the subordinate network, and continues the data transfer. Thereby, even if the wireless terminal device receiving the multicast data does not set up the uplink, the report message for the inquiry message can be transmitted to the data transfer device. Accordingly, multicast data being distributed from the radio base station apparatus is continuously transferred from the data transfer apparatus.
[0011]
In the third aspect of the invention, the following means is used to reduce the load on the radio base station apparatus under the condition of the second aspect of the invention. When receiving the inquiry message from the data transfer apparatus, the radio base station apparatus discards the inquiry message. The radio base station apparatus periodically generates a report message for each multicast data being distributed and transmits the report message to the data transfer apparatus. This process starts immediately after receiving the distribution start request message from the distribution setting device. Here, if the report message is transmitted to the data transfer apparatus at a period equal to or less than a certain time interval, the data transfer apparatus can interpret that the report message for the inquiry message has been received. Thereby, even if the wireless terminal device receiving the multicast data does not set up the uplink, the report message for the inquiry message can be transmitted to the data transfer device. Accordingly, multicast data being distributed from the radio base station apparatus is continuously transferred from the data transfer apparatus. In addition, since the radio base station apparatus can omit the process for receiving the inquiry message, the load is reduced.
[0012]
In the invention of claim 4, when receiving a multicast data delivery stop request message from the delivery setting device, the radio base station device stops delivery of the multicast data, generates a multicast data reception stop message, Send to data transfer device. When the data transfer apparatus can confirm that no other apparatus has received the multicast data in the subordinate network, the data transfer apparatus stops the transfer of the multicast data. As a result, even if a wireless terminal device that stops receiving multicast data does not set up an uplink, multicast data that is stopped by the wireless base station device can be stopped by the data transfer device. Transfer can be prevented.
[0013]
As described above, in the present invention, a reception start message, an inquiry message, a report message, and a reception stop message are transmitted / received between the wireless base station device and the data transfer device, and the wireless terminal device transmits / receives these messages. It is different from the prior art in that it is not necessary to do this. As a result, each message described above can be transmitted to the data transfer apparatus without using the uplink from the radio terminal apparatus, so that there is an effect that the restriction on the number of radio terminal apparatuses under the base station can be eliminated.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows the configuration of a data distribution system assumed by the present invention.
The data distribution system is configured by connecting a plurality of radio base stations 2 ₁ , 2 ₂ ,..., A data transfer apparatus 4 and a server 5 constituting a network under the control of the data transfer apparatus 4 via the network. . The distribution setting device (wireless connection) 3 ₁ is connected to the wireless base station device 2, and the distribution setting device (network connection) 3 ₂ is connected to the data transfer device 4. Further, there are wireless terminal devices 1 ₁ , 1 ₂ ,... That are broadcast targets in the area under the wireless base station device. In the network under the control of the data transfer device, there are a plurality of radio base station devices 2 ₁ , 2 ₂ ,... And other devices that receive multicast data are assumed.
Each multicast data of the server 5 is transmitted to the wireless terminal device 1 via the data transfer device 4 and the wireless base station device 2.
A multicast data distribution start request message / distribution stop request message is transmitted from the distribution setting device 3 ₁ wirelessly connected by the administrator or the distribution setting device 3 ₂ connected to the network to the wireless base station device 2.
Transmission / reception of a reception start message, an inquiry message, a report message, and a reception stop message is performed between the radio base station apparatus 2 and the data transfer apparatus 4.
The wireless terminal device 1 (all wireless terminal devices under the wireless base station device) receives multicast data from the wireless base station device 2.
[0015]
FIG. 2 shows a sequence at the start of distribution of multicast data according to the first aspect of the present invention. FIG. 3 shows the configuration of a radio base station apparatus for realizing the invention of claim 1.
When the wireless base station device 2 receives a distribution request message for certain multicast data from the distribution setting device 3 (distribution start request message receiving means 2-1), it generates a reception start message for the multicast data (reception start message generation). Means 2-2), and transmits this to the data transfer device 4 (reception start message transmission means 2-3). Thereby, the data transfer device 4 starts the transfer when the multicast data is not transferred. Further, when receiving the distribution start request message from the distribution setting device 3, the wireless base station device 2 sets a wireless connection for distributing the multicast data to the wireless terminal device 1. The multicast data received from the data transfer device 4 is converted into data to be transmitted wirelessly and distributed to the wireless terminal device 1 through the wireless connection (multicast data receiving means 2-4, multicast data distributing means 2-5). ).
[0016]
FIG. 4 shows a sequence when multicast data distribution is continued according to the invention of claim 2. FIG. 5 shows the configuration of a radio base station apparatus for realizing the invention of claim 2.
The inquiry message received by the wireless base station apparatus 2 from the data transfer apparatus 4 (inquiry message receiving means 2-6) includes two inquiry messages for specific multicast data and an inquiry message for requesting a report message for all multicasts. It is assumed that there are types. In the former case, when the multicast data specified by the inquiry message is being distributed, the radio base station apparatus 2 generates a report message for the multicast data (report message generating means 2-7) and sends this to the data transfer apparatus. Transmit (report message transmission means 2-8). In the latter case, a report message of all multicast data being distributed is generated from the radio base station apparatus and transmitted to the data transfer apparatus. When the data transfer apparatus receives the report message, the data transfer apparatus continues to transfer multicast data targeted by the report message.
[0017]
FIG. 6 shows a sequence when multicast data distribution is continued according to the invention of claim 3. FIG. 7 shows the configuration of the radio base station apparatus 2 for realizing the invention of claim 3.
The radio base station apparatus 2 generates a report message for the multicast data periodically within a certain interval (time) immediately after receiving the multicast data distribution start message from the distribution setting apparatus 3 (report message generating means ( 2-9) and periodically transmitted to the data transfer device 4. At this time, the inquiry message from the data transfer device 4 is ignored. If the period for transmitting the report message is shorter than the report message waiting timer in the data transfer apparatus, the data transfer apparatus will not time out, and thus the transfer of each multicast data can be continued.
[0018]
FIG. 8 shows a sequence when multicast data distribution is stopped according to the invention of claim 4. FIG. 9 shows the configuration of a radio base station apparatus for realizing the invention of claim 4.
When receiving the multicast data distribution stop request message from the distribution setting apparatus 3 by the administrator (distribution stop request message receiving means 2-10), the radio base station apparatus 2 stops the distribution of the multicast data and uses it for distribution. Release the existing wireless connection (multicast data distribution means 2-5). In addition, a multicast data reception stop message is generated (reception stop message generation means 2-12), and this is transmitted to the data transfer apparatus 4 (reception stop message transmission means 2-13). The data transfer device 4 stops the transfer of the multicast data when there is no other device receiving the multicast data in the subordinate network.
[0019]
The present invention can be used when distributing IP multicast data wirelessly. A router connected to the radio base station apparatus corresponds to a data transfer apparatus. The router manages the presence / absence of a device that receives each multicast data using an IGMP message. The reception start message and report message correspond to IGMP Report, the inquiry message corresponds to IGMP Query, and the reception stop message corresponds to IGMP Leave.
[0020]
In the invention of claim 1, when a multicast data distribution start request message is transmitted from the distribution setting device to the radio base station device, the radio base station device generates an IGMP Report packet destined for the multicast address. And send this to the router. If the router does not transfer the multicast data to the subordinate network, the router starts the transfer.
[0021]
In the invention of claim 2, the router transmits the IGMP Query to the subordinate network. This is received by the radio base station apparatus. In the case of General Query, an IGMP Report packet destined for each multicast address is generated for all multicast data being distributed from the radio base station apparatus, and these are transmitted to the router. In the case of the group-specific query, when the designated multicast data is being distributed from the radio base station apparatus, an IGMP Report packet destined for the multicast address is generated and transmitted to the router. When receiving the IGMP Report, the router continues to transfer the multicast data. If the IGMP Report is not received for a certain period of time, the multicast data transfer is stopped.
[0022]
In the invention of claim 3, even if the IGMP Query message is received from the router, it is ignored by the radio base station apparatus. In the radio base station apparatus, an IGMP Report packet of each multicast data being distributed is periodically generated at intervals of a predetermined time or less and transmitted to the router. When receiving this, the router interprets that the IGMP Report for the transmitted IGMP Query has been received, and continues to transfer the multicast data.
[0023]
In a fourth aspect of the present invention, when a distribution stop request message for multicast data being distributed is transmitted from the distribution setting apparatus to the radio base station apparatus, the radio base station apparatus generates an IGMP leave whose destination is the multicast address And send it to the router. Upon receiving this, the router stops forwarding the multicast data if it can be confirmed that another device is not receiving the multicast data. As this confirmation method, a method of transmitting a group-specific query of the multicast data to a subordinate network is used.
[0024]
【The invention's effect】
In the first aspect of the invention, when the wireless terminal device starts receiving the multicast data, the wireless base station device transmits a reception start message to the data transfer device instead of the wireless terminal device. Multicast data can be transferred from the data transfer device without using the uplink (the reception-only wireless terminal device can be used). As a result, there is an effect that there is no limitation on the number of wireless terminal devices that can receive multicast data under the control of the wireless base station.
[0025]
In the invention according to claim 2, in response to the inquiry message from the data transfer apparatus, the data transfer apparatus transmits multicast data by transmitting a report message to the data transfer apparatus instead of the radio terminal apparatus. Continue. Thereby, even when there is no uplink from the wireless terminal device, there is an effect that multicast data being distributed by the wireless base station device can be continuously transferred from the data transfer device.
In the invention of claim 3, in the invention of claim 2, since the radio base station apparatus can omit the reception process of the inquiry message from the data transfer apparatus by periodically transmitting the report message, Is effective.
[0026]
In the invention of claim 4, when the distribution of multicast data from the radio base station apparatus is stopped, even if there is no uplink from the radio terminal apparatus, a reception stop message is transmitted from the radio base station apparatus to the data transfer apparatus As a result, the transfer of the multicast data can be stopped. As a result, it is possible to prevent useless transfer of multicast data.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a data distribution system for distributing multicast data assumed by the present invention.
FIG. 2 is a sequence chart when multicast data distribution starts.
FIG. 3 is a configuration diagram of a radio base station apparatus necessary for starting distribution of multicast data.
FIG. 4 is a sequence chart when multicast data distribution is continued. (When sending a report message for an inquiry message)
FIG. 5 is a configuration diagram of a radio base station apparatus necessary for continuing distribution of multicast data. (When sending a report message for an inquiry message)
FIG. 6 is a sequence chart when distribution of multicast data is continued. (When sending report messages periodically)
FIG. 7 is a configuration diagram of a radio base station apparatus necessary for continuing distribution of multicast data. (When sending report messages periodically)
FIG. 8 is a sequence chart when distribution of multicast data is stopped.
FIG. 9 is a configuration diagram of a radio base station apparatus necessary for stopping the distribution of multicast data.
FIG. 10 is a sequence chart at the start of distribution of multicast data, continued distribution, and stopped distribution of conventional multicast data.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Wireless terminal device, 2 ... Wireless base station device, 3 ... Distribution setting device, 4 ... Data transfer device, 5 ... Server

Claims (4)

When receiving a reception start message for notifying the start of reception of certain multicast data from a device belonging to the subordinate network, it has a function to broadcast multicast data of the server to devices belonging to the subordinate network. When multicast data is not being transferred to a subordinate network, the data transfer device having a function of starting transfer of the multicast data and the multicast data transferred from the data transfer device under the control of the data transfer device A wireless base station device having a function of broadcasting to a plurality of wireless terminal devices using a common wireless connection, and the wireless base station device is subordinate to the wireless base station device and distributed from the wireless base station device Data distribution consisting of wireless terminal devices that receive multicast data In the stem,
A distribution setting device that has a function of transmitting a distribution start request message for requesting distribution start of multicast data, which is wirelessly connected or network-connected to the radio base station device;
When the wireless base station device receives a multicast data distribution start request message from the distribution setting device, the wireless base station device generates a reception start message generation / transmission unit that generates the multicast data reception start message and transmits the multicast data reception start message to the data transfer device. Have
Multicast data specified by the distribution setting device starts to be transferred by the data transfer device and distributed by the wireless base station device without transmitting a reception start message from the wireless terminal device that receives the multicast data using the uplink. Data distribution system characterized by that can start. The data distribution system according to claim 1,
The data transfer device has means for transmitting an inquiry message for confirming whether or not there is a device receiving each multicast data being transferred to a subordinate radio base station device,
When the wireless base station device receives the inquiry message from the data transfer device, if the multicast data targeted by the inquiry message is being delivered from the wireless base station device to the subordinate wireless terminal device, the multicast data report message And a report message generating / transmitting means for transmitting to the data transfer device,
When the data transfer apparatus receives a report message for notifying that multicast data is being received from a subordinate radio base station apparatus as a response to the inquiry message, there is an apparatus that is receiving the multicast data. Then, it has a data transfer continuation means that recognizes and continues to transfer the multicast data,
The multicast data being distributed by the radio base station device is continuously transferred by the data transfer device without transmitting a report message from the radio terminal device receiving the multicast data using the uplink, and the radio base station device A data distribution system characterized in that it can be distributed continuously. The data distribution system according to claim 1,
The radio base station apparatus periodically generates a report message of each multicast data distributed to the subordinate radio terminal apparatus, and has a report message generation / transmission means for transmitting to the data transfer apparatus,
When the data transfer apparatus receives a report message for notifying that multicast data is being received from a subordinate radio base station apparatus, the data transfer apparatus recognizes that there is an apparatus receiving the multicast data and A data transfer continuation means for continuing the data transfer;
The multicast data being distributed by the radio base station device is continuously transferred by the data transfer device without transmitting a report message from the radio terminal device receiving the multicast data using the uplink, and the radio base station device A data distribution system characterized in that it can be distributed continuously and the load on the radio base station apparatus can be reduced. The data distribution system according to any one of claims 1 to 3,
The distribution setting device has means for transmitting a distribution stop request message, which is a message requesting to stop distribution of multicast data, to the base station device,
When the wireless base station apparatus receives a multicast data distribution stop request message from the distribution setting apparatus, the radio base station apparatus generates a reception stop message generation / transmission unit that generates the multicast data reception stop message and transmits the multicast data reception stop message to the data transfer apparatus. Have
When the data transfer apparatus receives a reception stop message for notifying the reception stop of certain multicast data from a subordinate radio base station apparatus, if another apparatus is not receiving the multicast data in the subordinate network, Means for stopping the transfer of multicast data;
Multicast data whose distribution is stopped by the radio base station apparatus can be stopped by the data transfer apparatus without transmitting a reception stop message from the radio terminal apparatus using the uplink, so that unnecessary multicast data transfer can be prevented. A data distribution system characterized by

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