Mobile multicast system for supporting network-based mobility and method thereof

1. A method comprising:

transferring a general query message to managers of a mobility control server in response to receiving, from a router, the general query message for detecting a mobile node that requested to receive multicast data;

storing, in a multicast mapping table, an address of the mobile node that requested to receive the multicast data when a membership report message of the mobile node is received from at least one of the managers and transferring the membership report message to the router;

forming a tunnel between the router and a manager that transfers the membership report message;

in response to receiving, from a second manager, a location registration message of a mobile node receiving the multicast data:

updating the multicast mapping table;

controlling cancellation of the tunnel between the manager and the router; and

forming a tunnel between the router and the second manager.

2. The method of claim 1 , further comprising:

generating an entry for a second mobile node at the multicast mapping table when receiving a membership join message from the second mobile node present at the manager, wherein the membership join message is a message for receiving the multicast data;

transmitting a location information ACK message to the manager to transmit the multicast data to the second mobile node through a previously formed tunnel; and

transferring a membership report message of the second mobile node, which is transferred through the manager, to the router.

3. The method of claim 1 , further comprising:

determining whether the manager includes at least one mobile node receiving the multicast data when a leave group request message is received from a mobile node through the manager, wherein the leave group request message is a request for interrupting reception of the multicast data; and

transmitting the leave group request message of the mobile node to the router when at least one mobile node is receiving the multicast data based on the determination result.

4. The method of claim 1 , further comprising:

determining whether the manager includes at least one mobile node receiving the multicast data when a leave group request message is received from a mobile node through the manager, wherein the leave group request message is a request for stopping reception of the multicast data;

transmitting the leave group request message of the mobile node to the router when no mobile node is receiving the multicast data through the manager based on the determination result; and controlling cancellation of the tunnel between the router and the manager.

5. The method of claim 1 , wherein the location registration is received from the second manager because the mobile node moves to another access network.

6. The method of claim 1 , wherein the multicast mapping table includes mapping information of a 3 layer address of the mobile node, a layer 2 (L2) address of the mobile node, a multicast group address, a layer 3 (L3) address of the manager, a layer 3 (L3) address of the router.

7. A method comprising:

receiving a general query message for detecting a mobile node that requested to receive multicast data from a mobility control server and transferring the received general query message to mobile nodes through an access point, wherein the mobile nodes include a first mobile node;

receiving a membership report message from the first mobile node that requested to receive the multicast data and transferring the received membership report message to the mobility control server;

setting up an interface of a packet received at the first mobile node at a binding table when a tunnel between the first mobile node and the multicast router is formed in response to the membership report message from the mobility control server; and

transferring the multicast packet received at the first mobile node through the interface when the at least one mobile node receives the multicast packet from the multicast router through the tunnel;

when the mobility control server requests cancellation of the tunnel between the at least one mobile node and the multicast router, deleting the interface of the first node from the binding table and cancelling the tunnel between the multicast router and the at least one mobile node.

8. A method comprising:

transmitting a general query message for detecting a mobile node that requested to receive the multicast data from the mobility control server at a predetermined time interval;

when a membership report message of the mobile node and information about the manager is received from the mobility control server, forming a tunnel between the mobile node that requested to receive the multicast data and a manager that communicates with the mobile node;

transmitting the multicast data to the mobile node through the tunnel;

when a location information ACK message is received from the mobility control server while transmitting the multicast data to the mobile node through the router, cancelling the tunnel between the mobile node and the router, wherein the location information ACK message is a message requesting changing the manager of the mobile node; and

forming a tunnel between the mobile node and a second manager indicated by the mobility control server and transmitting the multicast data to the mobile node through the tunnel.

9. The method of claim 8 , further comprising:

cancelling the tunnel to the manager when the mobility control server requests cancellation of the tunnel to the manager;

generating a source-specific query message when the leave group request message is received after cancelling the tunnel, and transmitting the generated source-specific query message to the mobility control server at a predetermined time interval in order to detect a mobile node that wants to receive the multicast data; and

interrupting transmitting the multicast data when receiving no acknowledgement from the mobility control server after transmitting the source-specific query message predetermined times.

10. A mobile multicast system comprising:

access points configured to communicate with mobile nodes having no mobility supporting function in an access network through a wireless channel and to obtain and provide a 2 layer (L2) address of a mobile node;

managers configured to control a handover process of each mobile node associated with the access points and to transmit a multicast packet to the mobile node;

a router configured to receive multicast data through a network and to transmit the multicast packet to a mobile node that requested to receive the multicast data; and

a mobility control server configured to

obtain location information of a mobile node from the managers;

determine whether a mobile node is registered for a multicast service or not by transmitting a query message for determining whether multicast data is received or not to the managers when the query message is received from the router;

form a tunnel between the router and a manager that transmits a membership report message when the membership report message for registering the multicast service is received;

add information about a second mobile node at a multicast mapping table when the membership report message is received from the second mobile node when a tunnel is previously formed between a manager of the second mobile node and the router to transmit the multicast packet; and

control transmission of the multicast packet to the second mobile node through the tunnel between the manager of the second mobile node and the router.

11. The mobile multicast system of claim 10 , wherein the router is configured to:

generate a general query message for detecting a mobile node that requested to receive the multicast data and

regularly transmit the generated general query message to the mobility control server;

cancel a tunnel to at least one manager when a request for cancellation of the tunnel to the at least one manager is received from the mobility control server;

when a leave group request message is received, generate a source-specific query message and transmit the generated source-specific query message predetermined times at a predetermined interval; and

interrupt transmission of the multicast packet when no acknowledgement is received from the mobility control server.

12. The mobile multicast system of claim 10 , wherein the multicast mapping table includes information about a layer 3 (L3) address of the mobile node, a layer 2 (L2) address of the mobile node, a multicast group address, a layer 3 (L3) address of the manager, and a layer 3 (L3) address of the router.