Service data unit discard system for radio access networks

• US 8,270,369 B1
• Filed: 11/10/2008
• Issued: 09/18/2012
• Est. Priority Date: 11/16/2007
• Status: Active Grant

• Current Assignee: Marvell Asia Pte Limited (Marvell Technology Group Limited)
• Original Assignee: Marvell International Limited (Marvell Technology Group Limited)
• Inventors: Chang, Ilwoo
• Primary Examiner(s): Sheikh, Ayaz
• Assistant Examiner(s): Haliyur, Venkatesh
• Application Number:
  US12/267,958
• Time in Patent Office: 1,408 Days
• Field of Search: 370328-442
• US Class Current: 370/331
• CPC Class Codes: H04L 1/1607 Details of the supervisory signal
• CPC Class Codes: H04W 36/02 Buffering or recovering information during reselection ; Modification of the traffic flow during hand-off
• CPC Class Codes: H04W 36/026 Multicasting of data during hand-off
• CPC Class Codes: H04W 72/30 Resource management for broadcast services

Abstract

A network device includes a transceiver that transmits N packets to a first access point and that receives a control message from a second access point. The control message indicates reception of one of the N packets by the second access point from the first access point during a handover of the network device from the first access point to the second access point. N is an integer. A control module causes the transceiver to refrain from transmitting the one of the N packets to the second access point based on the control message. The handover of the network device from the first access point to the second access point occurs prior to the control message being received by the transceiver.

Claims

1. A network device comprising:

a transceiver configured to (i) transmit N packets to a first access point, and (ii) receive a control message from a second access point, where N is an integer, and wherein

the N packets include a first packet and a second packet, and

the control message indicates (i) reception of M of the N packets including the first packet by the second access point from the first access point during a handover of the network device from the first access point to the second access point, and (ii) reception of a redundant packet by the second access point, where M is an integer less than N, wherein the handover of the network device from the first access point to the second access point occurs prior to the control message being received by the transceiver; and

a control module configured to (i) begin transmitting the first packet to the second access point via the transceiver, and then (ii) receive the control message from the second access point,

wherein the control module is configured to (i) detect transmission of the redundant packet based on the control message, and (ii) the first packet and the second packet to the second access point in response to detecting the transmission of the redundant packet,

wherein the control module is configured to transmit N-M of the N packets to the second access point via the transceiver (i) subsequent to receiving the control message, and (ii) in response to a predetermined period expiring, wherein the N-M packets were unsuccessfully transmitted from the first access point to the second access point, and wherein the control module is configured to discard the M packets (i) prior to the predetermined period expiring, and (ii) in response to the control message.

2. The network device of claim 1, wherein:

the first access point received the first packet in a first radio access network; and

the second access point received the first packet in a second radio access network.

3. The network device of claim 1, wherein the control message is (i) initially generated within a packet data convergence protocol layer of the second access point, or (ii) initially generated as a packet data convergence protocol layer control packet data unit.

4. The network device of claim 1, wherein the transceiver is configured to transmit:

a first set of service data units to the first access point, the first set of service data units including the N packets; and

a second set of service data units to the second access point, the second set of service data units including the one of the N packets.

5. The network device of claim 1, wherein the transceiver is configured to receive the control message prior to transmitting the one of the N packets to the second access point.

6. The network device of claim 1, wherein the transceiver is configured to transmit the one of the N packets to the second access point based on reception of an acknowledgement signal from the first access point.

12. The network device of claim 1, wherein:

the transceiver is configured to transmit a message window signal to the second access point subsequent to (i) the predetermined period expiring, (ii) transmission of the N-M packets from the transceiver to the second access point, or (iii) refraining from transmitting the first packet and the second packet; and

the message window signal indicates (i) transmission of the N-M packets from the transceiver to the second access point, and (ii) the transceiver discarding the N-M packets.

13. The network device of claim 1, wherein the redundant packet includes the first packet.

7. A target access point comprising:

a transceiver configured to receive M of N packets associated with a service request device, where N and M are integers and M is less than N, and wherein

the N packets include a first packet and a second packet,

the M packets are received by the transceiver from a first access point during a handover of the service request device from the first access point to the target access point,

the N packets are transmitted from the service request device to the first access point; and

a control module configured to generate a control message, wherein the control message indicates (i) reception of the M packets including the first packet by the transceiver from the first access point, and (ii) reception of a redundant packet by the transceiver,

wherein the control module is configured to (i) begin receiving the first packet from the service request device, and then (ii) detect the reception of the redundant packet,

wherein the transceiver is configured to, in response to detecting the reception of the redundant packet, transmit the control message to the service request device to prevent the service request device from transmitting the first packet and the second packet, to the target access point, wherein the control module is configured to receive N-M of the N packets from the service request device via the transceiver (i) subsequent to transmitting the control message, and (ii) in response to a predetermined period expiring, wherein the N-M packets were unsuccessfully transmitted from the first access point to the target access point, and wherein the service request device discards the M packets (i) prior to the predetermined period expiring, and (ii) in response to the control message.

8. The target access point of claim 7, wherein the service request device is configured to transmit the N packets to the first access point prior to the handover of the service request device from the first access point to the target access point.

9. The target access point of claim 7, wherein the control message is (i) initially generated within a packet data convergence protocol layer of the transceiver, or (ii) initially generated as a packet data convergence protocol layer control packet data unit.

10. The target access point of claim 7, wherein the transceiver is configured to receive the one of the N packets from the service request device based on reception of an acknowledgement signal by the service request device from the first access point.

11. A method of operating a target access point, the method comprising:

receiving M of N packets associated with a service request device via a transceiver, where M and N are integers and M is less than N, and wherein

the N packets include a first packet and a second packet,

the M packets are received by the transceiver from a first access point during a handover of the service request device from the first access point to the target access point, and

the N packets are transmitted from the service request device to the first access point;

generating a control message,

wherein the control message indicates (i) reception of the M packets including the first packet by the transceiver from the first access point, and (ii) reception of a redundant packet by the transceiver;

beginning reception of the first packet from the service request device;

detecting the reception of the redundant packet subsequent to beginning reception of the first packet;

in response to detecting the reception of the redundant packet, transmitting the control message to the service request device to prevent the service request device from transmitting the packets first packet and the second packet to the target access point; and

receiving N-M of the N packets from the service request device via the transceiver (i) subsequent to transmitting the control message, and (ii) in response to a predetermined period expiring, wherein the N-M packets were unsuccessfully transmitted from the first access point to the target access point, wherein the service request device discards the M packets (i) prior to the predetermined period expiring, and (ii) in response to the control message.