Method, apparatus and system for distributing multicast data

• US 20040264463A1
• Filed: 03/02/2004
• Published: 12/30/2004
• Est. Priority Date: 06/26/2003
• Status: Active Grant

• Current Assignee: Alaxala Networks Corporation (Fortinet Inc.)
• Original Assignee: Hitachi, Ltd.
• Inventors: Fukushima, Hidehiro, Morimoto, Shigeki
• Granted Patent: US 7,606,227 B2
• Time in Patent Office: Days
• US Class Current: 370/390
• CPC Class Codes: H04L 12/184 with heterogeneous receivers, e.g. layered multicast
• CPC Class Codes: H04L 12/185 with management of multicast group membership
• CPC Class Codes: H04L 12/189 in combination with wireless systems selective distribution or broadcast in wireless communication networks H04W4/06
• CPC Class Codes: H04L 12/4633 Interconnection of networks using encapsulation techniques, e.g. tunneling
• CPC Class Codes: H04L 45/16 Multipoint routing
• CPC Class Codes: H04W 40/36 due to handover
• CPC Class Codes: H04W 60/04 using triggered events
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]

Abstract

Packets of mobile communication protocol which a mobile terminal sends and receives are monitored and when it is detected that a mobile terminal to which a multicast data packet is transferred moved to another network, a multicast gateway apparatus connected to the moving destination network makes a group attend request and transfers the multicast data packet to the moved mobile terminal.

Claims

1. A method for distributing data multicast sent from a source addressed to a receiving terminal which does not support a multicast function via gateway, the multicast distribution method comprising the steps of:

detecting a data request packet sent from receiving terminal registered in a first network to the source at a first gateway located on transfer path of packet between the receiving terminal and the source;

retaining address of the receiving terminal included in the data request packet;

detecting registration message which the receiving terminal issued to a second network;

sending a receive state information packet including information relating address information of the source and destination address information of data multicast sent to a second gateway located on transfer path of packet between the second network and the source;

sending from the second gateway a distribution request packet of multicast data based on received receive state information packet to the source; and

converting address information of multicast data packet sent from the source to address of the receiving terminal and sending it to the receiving terminal.

2. A multicast gateway apparatus which transfers a data packet multicast sent from a source addressed to a receiving terminal requesting to receive the data packet, comprising:

a packet receiving part which receives a packet;

a packet discrimination part which discriminates a kind of received packet;

an access terminal management table which retains address of the receiving terminal which is a source of received packet when received packet is an access request packet to the source;

a receiving terminal management table which, when received packet is a registration request packet of receiving terminal, retains address of moving destination of the terminal included in the registration request packet;

a data transfer processing part which, when received packet is a data packet multicast sent, sets address of moving destination of the receiving terminal as a destination address for the received data packet referring to the access management table and the receiving terminal management table; and

a unit for sending data packet with the address set to the receiving terminal.

3. A multicast gateway apparatus according to claim 2, further comprising:

a unit for receiving the control packet of mobile communication protocol which the receiving terminal sends and receives;

a unit for adding address information of the multicast gateway apparatus to the received control packet of mobile communication protocol and sending the control packet;

a unit for receiving the control packet of mobile communication protocol added with address information of the multicast gateway apparatus;

a unit for retaining address information of the multicast gateway apparatus included in the received control packet of mobile communication protocol added with address information of the multicast gateway apparatus; and

a unit for deleting address information of the multicast gateway apparatus included in the received control packet of mobile communication protocol added with address information of the multicast gateway apparatus.

4. A multicast gateway apparatus according to claim 2, further comprising:

a unit for monitoring packet sent and received between the receiving terminal and the source; and

a unit for generating a distribution packet which indicates distribution control of data packet multicast sent to the nearest multicast router apparatus based on monitoring result of the monitoring unit.

5. A multicast gateway apparatus according to claim 4, wherein the control packet is a packet of group management protocol.

6. A router apparatus which is provided with a relaying function of data packet multicast sent, comprising:

a packet receiving part which receives packet;

a packet discrimination part which discriminates a kind of received packet;

an access terminal management table which, when received packet is an access request packet to a source of multicast data, retains address of receiving terminal which is a source of the received packet;

a receiving terminal management table which, when received packet is a registration request packet of receiving terminal, retains address of moving destination of the terminal included in the registration request packet;

a data transfer processing part which, when received packet is a data packet multicast sent, sets address of moving destination of the receiving terminal as a destination address for the received data packet referring to the access management table and the receiving terminal management table; and

a unit for sending data packet with the address set to the receiving terminal.

7. A router apparatus according to claim 6, further comprising:

a unit for receiving the control packet of mobile communication protocol which the mobile terminal sends and receives;

a unit for adding address information of the router apparatus to the received control packet of mobile communication protocol and sending the control packet;

a unit for receiving the control packet of mobile communication protocol added with address information of the router apparatus;

a unit for retaining address information of the router apparatus included in the received control packet of mobile communication protocol added with address information of the router apparatus; and

a unit for deleting address information of the router apparatus included in the received control packet of mobile communication protocol added with address information of the router apparatus and sending the control packet.

8. A router apparatus according to claim 6, further comprising:

a unit for monitoring packet sent and received between the receiving terminal and the source; and

a unit for generating a control packet which indicates distribution control of data packet multicast sent to another router apparatus existing on network based on monitoring result of the monitoring unit.

9. A router apparatus according to claim 8, wherein the control packet is a packet of multicast path control protocol.

10. An agent apparatus in a network to which a mobile communication protocol is applied provided with a function defined by the mobile communication protocol, comprising:

a packet receiving part which receives packet;

a packet discrimination part which discriminates a kind of received packet;

an access terminal management table which, when received packet is an access request packet to a source of multicast data, retains address of receiving terminal which is a source of the received packet;

a receiving terminal management table which, when received packet is a registration request packet of receiving terminal, retains address of moving destination of the terminal included in the registration request packet;

a data transfer processing part which, when received packet is a data packet multicast sent, sets address of moving destination of the receiving terminal as a destination address for the received data packet referring to the access management table and the receiving terminal management table; and

a unit for sending data packet with the address set to the receiving terminal.

11. An agent apparatus according to claim 10, further comprising:

a unit for adding address information of the agent apparatus to the control packet of mobile communication protocol and sending the control packet;

a unit for receiving the control packet of mobile communication protocol added with address information of the agent apparatus;

a unit for retaining address information of the agent apparatus included in the received control packet of mobile communication protocol added with address information of the agent apparatus; and

a unit for deleting address information of the agent apparatus included in the received control packet of mobile communication protocol added with address information of the agent apparatus and sending the control packet.

12. A service system which distributes information to a receiving terminal which is not provided with a receiving function of multicast data using multicast communication, comprising:

a distribution server which multicast sends data packet including information to provide;

a home agent located in a home network to which the receiving terminal belongs;

a foreign agent located in a foreign network to which the receiving terminal can move;

a first multicast gateway apparatus located on a communication path between the home agent and the distribution server;

a second multicast gateway apparatus located on a communication path between the foreign agent and the distribution server;

wherein the first and the second multicast gateway apparatuses comprise a unit for converting data packet multicast sent to unicast data, and

the first multicast gateway apparatus, on receiving a registration message which the receiving terminal issued for the foreign agent, transfers address information of the distribution server and home address information of the receiving terminal to the second gateway,

the second gateway sends a distribution request packet of multicast data to the distribution server,

and further converts multicast data sent from the distribution server to unicast data and sends the unicast data to the receiving terminal.

13. A method for providing service which distributes data multicast sent from a distribution server to a receiving terminal which is not provided with a receiving function of multicast data, comprising the steps of:

detecting a data request packet sent from a receiving terminal registered in a first network to the distribution server at a first gateway located on a transfer path of packet between the receiving terminal and the distribution server;

retaining address of the receiving terminal included in the data request packet;

detecting that the receiving terminal moved to a second network by a registration message which the receiving terminal issued to the second network;

sending address information of the distribution server and destination address information of data to be multicast sent to the second gateway located on a transfer path of packet between the receiving terminal after moving to the second network and the distribution server;

sending a distribution request packet of multicast data to the distribution server from the second gateway;

converting destination address information of multicast data sent from the distribution server to address of the receiving terminal; and

sending multicast data with the destination address converted to the receiving terminal.