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CN-122029879-A - Timer-based discarding of data units

CN122029879ACN 122029879 ACN122029879 ACN 122029879ACN-122029879-A

Abstract

The present disclosure provides systems, apparatus, devices, and methods for discarding data units, including computer programs encoded on a storage medium. The UE (102) receives (420) a first indicator from the network entity (104) for enabling discarding of data units from a transmit buffer according to a first discard period. The UE discards (440 a) the first data unit from the transmit buffer after expiration of a first discard period starting when the first data unit arrives at the transmit buffer. The UE receives (450) from the network entity (104) a second indicator for enabling discarding of data units from the transmit buffer according to a second discard period having a length different from the first discard period. The UE discards (440 b) the second data unit from the transmit buffer after expiration of a second discard period starting when the second data unit arrives at the transmit buffer.

Inventors

  • YE XIANGRONG

Assignees

  • 谷歌有限责任公司

Dates

Publication Date
20260512
Application Date
20240911
Priority Date
20230929

Claims (15)

  1. 1. A method of wireless communication performed by a user equipment, UE, (102), the method comprising: -receiving (420) from the network entity (104) a first indicator for enabling discarding of data units from the transmit buffer according to a first discard period; -discarding (440 a) a first data unit from the transmission buffer after expiration of the first discard period starting when the first data unit arrives at the transmission buffer; Receiving (450) a second indicator from the network entity (104) for enabling discarding of data units from the transmit buffer according to a second discard period, the second discard period having a different length than the first discard period, and -Discarding (440 b) a second data unit from the transmission buffer after expiration of the second discard period starting when the second data unit arrives at the transmission buffer.
  2. 2. The method of claim 1, further comprising: -receiving (410) a configuration for data unit dropping from the network entity (104), the configuration comprising at least one of: A first discard period value (304); A second discard period value (305); A table of first discard period values (304) for a plurality of protocol data units, PDU, set importance, PSI; a table of second discard period values (305) for the plurality of PSIs; a table of scale factors for the plurality of PSIs; a table of first discard period values (304); a table of second discard period values (305); A table of scale factors; PSI group indicator, or PSI group threshold.
  3. 3. The method of any of claims 1-2, wherein the data unit comprises at least one of: PDU; A set of PDUs; A set of PDU sets; service data unit SDU; burst of data, or A burst of data.
  4. 4. A method according to any one of claims 1 to 3, wherein the second discard period (305) is shorter than the first discard period (304).
  5. 5. The method of any of claims 1 to 4, wherein the second discard period (305) is applied to the second data unit based on at least one of: The PSI of the second data unit, or The delay budget of the second data unit.
  6. 6. The method of any one of claims 1 to 5, wherein the second indicator indicates at least one of: -the second discard period value (305); storing an index of a table of second discard period values (305); a scale factor; Index of a table of scale factors, or PSI threshold.
  7. 7. The method of any one of claims 1 to 6, further comprising: -determining (455) the second drop period (305) by applying a scaling factor to the first drop period (304), wherein the applying the scaling factor comprises at least one of: dividing the first discard period by a multiple of the scaling factor; multiplying the first discard period by a multiple of the scale factor, or A multiple of the scaling factor is subtracted from the first discard period.
  8. 8. The method of any one of claims 1 to 7, further comprising: -sending (405) a set of data unit parameters to the network entity (104), the set of data unit parameters comprising at least one of: The amount of data of the data unit; a range of amounts of the data units; The data unit includes an indication of single-mode data; The data unit includes an indication of multimode data; PSI of the data unit; the data rate of the data unit, or The data rate range of the data unit.
  9. 9. The method of any one of claims 1 to 8, further comprising: -receiving (470) a third indicator from the network entity (104) for disabling the discarding of data units.
  10. 10. The method of any one of claims 1 to 9, further comprising: The first data unit and the second data unit are received from an application layer of the UE into a transmit buffer of the UE.
  11. 11. The method of any of claims 1 to 10, wherein the receiving (450) the second indicator comprises: The second indicator is received (450) via a downlink control information, DCI, or a medium access control, MAC-CE, message.
  12. 12. The method of any of claims 1 to 11, wherein the discarding the first data unit comprises: Discarding the first data unit having the first PSI, and After expiration of the first discard period, another data unit without the first PSI is reserved.
  13. 13. The method of any one of claims 1 to 12, further comprising: receiving a discard cycle parameter indicating a first discard cycle period and a second discard cycle period, Wherein: the discarding the first data unit further comprises: Receiving the first data unit into a transmit buffer during the first discard cycle period, and A fourth data unit is received into the transmit buffer during the second discard cycle period and is retained after expiration of the first discard period.
  14. 14. A method of wireless communication performed by a network entity (104), the method comprising: Transmitting (420) to the user equipment, UE, (102) a first indicator for enabling first data unit dropping according to a first dropping period starting when the first data unit arrives at the transmit buffer based on the network congestion level, and -Transmitting (450) a second indicator to the UE (102) for enabling discarding of a second data unit according to a second discard period starting when the second data unit arrives at the transmission buffer, the second discard period having a different length than the first discard period, based on the change in the network congestion level.
  15. 15. An apparatus for wireless communication, comprising a transceiver, a memory, and a processor coupled to the transceiver and the memory and configured to implement the method of any one of claims 1-14.

Description

Timer-based discarding of data units Cross Reference to Related Applications The present application claims the benefit and priority of U.S. provisional application serial No. 63/586,633, entitled "Timer Based Discarding of Data Units," filed on 9, 29, 2023, which is expressly incorporated herein by reference in its entirety. Technical Field The present disclosure relates generally to wireless communications, and more particularly, to methods and apparatus for timer-based discard of data units. Background The third generation partnership project (3 GPP) specifies a radio interface called the fifth generation (5G) New Radio (NR) (5G NR). The architecture of the 5G NR wireless communication system (5 GS) includes a 5G core (5 GC) network, a 5G radio access network (5G-RAN), user equipment (5G UE), and the like. The 5G NR architecture strives to provide increased data rates, reduced latency, and/or increased capacity compared to previous generations of cellular communication systems. Generally, wireless communication systems provide various telecommunication services (e.g., telephony), video, data, messaging, etc.) based on multiple access techniques, such as Orthogonal Frequency Division Multiple Access (OFDMA) techniques, that support communication with multiple UEs. Improvements in mobile broadband continue to advance in such wireless communication technologies. A User Equipment (UE) software application queues data that eventually arrives at a send buffer, such as a Service Data Adaptation Protocol (SDAP) buffer, a Packet Data Convergence Protocol (PDCP) buffer, a Radio Link Control (RLC) buffer, and/or a Medium Access Control (MAC) buffer, for transmission to a network entity. Data is organized into data units (e.g., protocol Data Units (PDUs), PDU sets, service Data Units (SDUs), data bursts, groups of data bursts, etc.). The data unit carries a payload of one information unit from the data generated at the upper layer. When a network entity detects network congestion, conventional UE data unit dropping procedures may not be able to alleviate the network congestion. Disclosure of Invention The following presents a simplified summary of one or more aspects in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects. This summary does not identify key or critical elements of all aspects nor delineate the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that is presented later. The data units sent by the UE may have different importance levels based on the type of data (e.g., i-frame video data, p-frame video data, audio data, haptic data, gesture data, etc.) and/or the application type associated with the data units (e.g., augmented reality (XR) application, conversational or live video, non-conversational or buffered video, conversational voice, etc.). The data units may be classified according to a PDU Set Importance (PSI) level that identifies the relative importance/priority of the data units as compared to other data units within a quality of service (QoS) flow. The Radio Access Network (RAN) uses the PSI for controlling UE data unit dropping (e.g., PDU set packet dropping) when network congestion is present. The network entity selects which UE(s) to enable for data unit dropping. For example, the network entity selects the UE based on a UE buffer status report or delay status report providing any of PSI of the data units, delay information for the data units, data rate based on the data units per PSI, and/or amount of data units in the UE's transmit buffer. The network entity sends (e.g., via broadcast, unicast, or multicast messaging) a first indicator to the selected UE to enable discarding of data units based on the first discard period and/or PSI. For example, the network entity indicates a first drop period value (e.g., a delay budget associated with the data unit) to the UE. When a data unit arrives at the transmit buffer (e.g., from an upper layer), the UE starts a discard timer. If the UE does not send a data unit before the timer expires, the UE discards the data unit with the indicated PSI. Each PSI may have the same or different discard time periods. When a data unit arrives in the transmit buffer, a discard timer is started for this new data unit. Alternatively, the same discard timer value is used for any PSI level, and if the UE does not send a data unit before the discard timer expires, the UE discards the data unit regardless of the PSI. In other words, the UE discards the data units during a time window (e.g., a rolling time window) that begins when each data unit arrives at the transmit buffer. Discarding the data unit after the expiration of the first discard timer helps to alleviate network congestion, since the discarded data unit will not be sent to the network entity. The network entity periodical