Granted Patent B1

US 8,301,137 · App. 09/630,024 · Granted Oct 30, 2012

Abstract

Claims (60)

1. A method implemented in a subscriber unit, wherein a multicast group comprises a plurality of subscriber units, the method comprising:

receiving a multicast group indication message, from a base station, via a first one of a plurality of wireless channels, the multicast group indication message identifying a connection identifier associated with a multicast message, wherein the connection identifier is associated with an indication of a second one of the plurality of wireless channels over which to receive the multicast message from the base station;

receiving the multicast message via the second one of the plurality of wireless channels;

transmitting a negative acknowledgment; and

receiving a retransmission of the multicast message in response to the transmitted negative acknowledgement.

2. The method of claim 1 further comprising:

receiving the multicast message concurrently with other subscriber units in the multicast group.

3. The method of claim 1 wherein the second one of the plurality of wireless channels is a dedicated channel.

4. The method of claim 1 wherein only a subscriber unit associated with the multicast group decodes the multicast message received over the second wireless channel.

5. A method of transmitting multicast messages, wherein a multicast group comprises a plurality of subscriber units, the method comprising:

transmitting a multicast group indication message, from a base station, via a first one of a plurality of wireless channels, the multicast group indication message identifying a connection identifier associated with a multicast message, wherein the connection identifier is associated with an indication of a second one of the plurality of wireless channels over which a corresponding multicast message will be transmitted from the base station; and

transmitting the multicast message, from the base station, to the multicast group via the second one of the plurality of wireless channels;

receiving a negative acknowledgment from a subscriber unit associated with the multicast group; and

retransmitting the multicast message.

6. The method of claim 5 further comprising:

performing a lookup in a routing table adapted to store entries associating a multicast group with the connection identifier; and

performing a lookup in a table adapted to associate the connection identifier with the at least one subscriber unit.

7. The method of claim 5 further comprising:

receiving a join group request from a subscriber unit; and

adding an entry in the table indicative of an association between the multicast group and the subscriber unit.

8. The method of claim 5 further comprising:

scanning the multicast message; and

parsing a group address in response to a determination that the multicast message is directed to the multicast group.

9. The method of claim 8 wherein the group address conforms to a protocol and the multicast message is parsed in accordance with the protocol.

10. The method of claim 9 wherein the protocol is the Internet Group Management Protocol (IGMP).

11. The method of claim 5 wherein the first one of the plurality of wireless channels is a dedicated channel.

12. The method of claim 5 , wherein the

retransmitting the multicast message includes retransmitting the multicast message via a third one of the plurality of channels.

13. A subscriber unit comprising:

a receiver configured to:

receive a multicast group indication message, from a base station, via a first one of a plurality of wireless channels, the multicast group indication message identifying a connection identifier associated with a multicast message, therein the connection identifier is associated with an indication of a second one of the plurality of wireless channels over which to receive a corresponding multicast message; and

receive the multicast message, from the base station, via the second one of the plurality of wireless channels; and

a transmitter configured to transmit a negative acknowledgement; and

wherein the receiver is further configured to receive a retransmission of the multicast message in response to the transmitted negative acknowledgement.

14. The subscriber unit of claim 13 wherein the second one of the plurality of wireless channels is a dedicated channel.

15. A base station for multicasting messages, the base station comprising:

a processor configured to receive a multicast message addressed to a multicast group having two or more subscriber units;

a transmitter configured to:

transmit a multicast group indication message to a multicast group via a first one of a plurality of wireless channels, the multicast group indication message identifying a connection identifier associated with a multicast message, wherein the connection identifier is associated with an indication of a second one of the plurality of wireless channels over which a corresponding multicast message will be transmitted; and

transmit the multicast message, to the multicast group, via the second one of the plurality of wireless channels; and

a receiver configured to receive a negative acknowledgment from a subscriber unit associated with the multicast group;

wherein the transmitter is further configured to retransmit the multicast message in response to the negative acknowledgement.

16. The base station of claim 15 wherein:

the processor is further configured to perform a lookup in a routing table adapted to store entries associating a multicast group with the connection identifier; and to perform a lookup in a table adapted to associate the connection identifier with the at least subscriber units.

17. The base station of claim 16 , further comprising:

a receiver configured to receive a join group request from a subscriber unit;

wherein the processor is further configured to add an entry in the table indicative of an association between the multicast group and the subscriber unit.

18. The base station of claim 15 wherein the processor is further configured to scan the multicast message; and to parse a group address in response to a determination that the multicast message is directed to the multicast group.

19. The base station of claim 18 wherein the group address conforms to a protocol and the multicast message is parsed by the processor in accordance with the protocol.

20. The base station of claim 19 wherein the protocol is the Internet Group Management Protocol (IGMP).

21. The base station of claim 20 wherein the first one of the plurality of wireless channels is a dedicated channel.

22. The base station of claim 15 ,

wherein the transmitter is configured to retransmit the multicast message via the second one of the plurality of wireless channels in response to the negative acknowledgement.

23. The method of claim 1 ,

wherein the retransmission of the multicast message is received via the second one of a plurality of wireless channels.

24. The subscriber unit of claim 13 , wherein the receiver is configured to receive the retransmission of the multicast message via the second one of the plurality of wireless channels in response to the transmitted negative acknowledgement.

25. The method of claim 1 , wherein the retransmission of the multicast message is received via a third one of a plurality of wireless channels.

26. The method of claim 5 , wherein the retransmitting the multicast message includes retransmitting the multicast message via the second one of the plurality of channels.

27. The subscriber unit of claim 13 , wherein the receiver is configured to receive the retransmission of the multicast message via a third one of the plurality of wireless channels in response to the transmitted negative acknowledgement.

28. The base station of claim 15 , wherein the transmitter is configured to retransmit the multicast message via a third one of the plurality of wireless channels in response to the negative acknowledgement.

Assignments (8)