Method and Apparatus for PCDP Discard

• US 20170237837A1
• Filed: 05/01/2017
• Published: 08/17/2017
• Est. Priority Date: 10/01/2007
• Status: Active Grant

• Current Assignee: InterDigital Patent Holdings, Inc. (InterDigital, Inc.)
• Original Assignee: InterDigital Patent Holdings, Inc. (InterDigital, Inc.)
• Inventors: Sammour, Mohammed, Terry, Stephen E.
• Granted Patent: US 10,630,819 B2
• Time in Patent Office: Days
• CPC Class Codes: H04L 1/1874 Buffer management
• CPC Class Codes: H04L 1/188 Time-out mechanisms
• CPC Class Codes: H04L 47/283 in response to processing delays, e.g. caused by jitter or round trip time [RTT]
• CPC Class Codes: H04L 47/32 by discarding or delaying data units, e.g. packets or frames
• CPC Class Codes: H04L 69/04 Protocols for data compression, e.g. ROHC
• CPC Class Codes: H04L 69/28 Timers or timing mechanisms used in protocols
• CPC Class Codes: H04L 69/324 in the data link layer [OSI layer 2], e.g. HDLC
• CPC Class Codes: H04W 28/0205 at the air interface dynamic wireless traffic scheduling H04W72/12
• CPC Class Codes: H04W 80/02 Data link layer protocols

Abstract

A method and apparatus for discarding a packet data convergence protocol (PDCP) service data unit (SDU) are disclosed. A PDCP layer sets a timer and discards a PDCP SDU upon expiration of the timer. The timer may be set upon receiving the PDCP SDU from an upper layer or upon submitting the PDCP SDU to a lower layer for transmission. The timer and a radio link control (RLC) discard timer may be coordinated. Alternatively, the PDCP layer may discard the PDCP SDU based on a notification from an RLC layer or based on a PDCP status report.

Claims

1-5. -5. (canceled)

6. A method for discarding a packet data convergence protocol (PDCP) packet, the method comprising:

a PDCP receiving a PDCP service data unit (SDU) from upper layers;

the PDCP entity processing the PDCP SDU to form a PDCP protocol data unit (PDU);

the PDCP entity sending the PDCP PDU to a radio link control (RLC) entity;

the PDCP entity receiving a PDCP status report, wherein the PDCP status report indicates that the PDCP SDU has been successfully delivered to a receiving PDCP entity;

the PDCP entity discarding the PDCP SDU based on the PDCP status report; and

the PDCP entity sending an indication of the discard to the RLC entity.

7. The method as in claim 6, further comprising the RLC entity discarding a RLC SDU corresponding to the PDCP PDU based on receiving the indication of the discard.

8. The method as in claim 6, wherein the PDCP status report is included in a PDCP control PDU.

9. The method as in claim 6, further comprising the PDCP entity discarding the PDCP PDU based on the PDCP status report.

10. The method as in claim 6, wherein the PDCP entity processing the PDCP SDU to form the PDCP PDU comprises the PDCP entity adding a PDCP sequence number to the PDCP SDU, and the PDCP entity performing header compression on the PDCP SDU.

11-15. -15. (canceled)

16. A wireless transmit receive unit (WTRU) comprising a PDCP entity configured to:

receive a PDCP service data unit (SDU) from an upper layer entity;

process the PDCP SDU to form a PDCP protocol data unit (PDU);

send the PDCP PDU to a radio link control (RLC) entity;

receive a PDCP status report, wherein the PDCP status report indicates that the PDCP SDU has been successfully delivered to a receiving PDCP entity;

discard the PDCP SDU based on the PDCP status report; and

send an indication of the discard to the RLC entity.

17. The WTRU as in claim 16, further comprising the RLC entity, wherein the RLC entity is configured to discard a RLC SDU corresponding to the PDCP PDU based on receiving the indication of the discard.

18. The WTRU as in claim 16, wherein the PDCP status report is included in a PDCP control PDU.

19. The WTRU as in claim 16, wherein the PDCP entity is further configured to discard the PDCP PDU based on the PDCP status report.

20. The WTRU as in claim 16, wherein the PDCP entity is configured to process the PDCP SDU to form the PDCP PDU by adding a PDCP sequence number to the PDCP SDU, and performing header compression on the PDCP SDU.