WO2025170520A1

WO2025170520A1 - Flexible radio link control retransmissions for radio link control acknowledged mode for time critical services

Info

Publication number: WO2025170520A1
Application number: PCT/SE2025/050086
Authority: WO
Inventors: Richard TANO; Jose Luis Pradas; Du Ho Kang; Fabian DE LAVAL
Original assignee: Telefonaktiebolaget LM Ericsson AB
Current assignee: Telefonaktiebolaget LM Ericsson AB
Priority date: 2024-02-05
Filing date: 2025-02-04
Publication date: 2025-08-14
Anticipated expiration: 2026-08-05

Abstract

A method (1500) performed by a receiving radio node (710, 712) for RLC transmissions includes receiving (1502), from a transmitting node (710, 712), information indicating that at least one RLC PDU is not to be retransmitted by the transmitting radio node. The receiving radio node takes at least one action (1504) associated with the at least one RLC PDU not to be retransmitted to the receiving radio node. For example, taking the at least one action includes updating at least one parameter associated with an RLC receiving window.

Description

FLEXIBLE RADIO LINK CONTROL RETRANSMISSIONS FOR RADIO LINK CONTROL

ACKNOWLEDGED MODE FOR TIME CRITICAL SERVICES

TECHNICAL FIELD

The present disclosure relates, in general, to wireless communications and, more particularly, systems and methods for flexible Radio Link Control (RLC) retransmissions for Radio Link Control-Acknowledged Mode (RLC-AM) for time critical services.

BACKGROUND

5G is the fifth generation of mobile communications, addressing a wide range of use cases from enhanced mobile broadband (eMBB) to ultra-reliable low-latency communications (URLLC) to massive machine type communications (mMTC). 5G includes the New Radio (NR) access stratum interface and the 5G Core Network (5GC). The NR physical and higher layers are reusing parts of the Long Term Evolution (LTE) specification and, to that, add needed components when motivated by new use cases.

Low-latency high-rate applications such as extended Reality (XR) and cloud gaming are important in 5G era. XR may refer to all real -and- virtual combined environments and humanmachine interactions generated by computer technology and wearables. It is an umbrella term for different types of realities including Virtual reality (VR), Augmented reality (AR), Mixed reality (MR), and the areas interpolated among them. The levels of virtuality range from partially sensory inputs to fully immersive VR.

5G NR is designed to support applications demanding high rate and low latency in line with the requirements posed by the support of XR and cloud gaming applications in NR networks. 3 GPP Release 19 contains a study item on XR Evaluations for NR. See, RP-210460, Study on XR (Extended Reality) evaluations for NR. The main objectives are to identify the traffic model for each application of interest, the evaluation methodology and the key performance indicators of interest for relevant deployment scenarios, and to carry out performance evaluations accordingly in order to investigate possible standardization enhancements in potential follow-up Study Items/Work Items.

Low -Latency High-Rate XR Applications

The low-latency applications like XR and cloud gaming require bounded latency, not necessarily ultra-low latency. The end-to-end latency budget may be in the range of 20-80 ms, which needs to be distributed over several components including application processing latency, transport latency, radio link latency, etc. For these applications, short transmission time intervals (TTIs) or mini-slots targeting ultra-low latency may not be effective.

FIGURE 1 illustrates an example of frame latency measured over radio access network (RAN), excluding application & core network latencies. It can be seen that there exist frame latency spikes in RAN. The latency spikes occur due to instantaneous shortage of radio resources or inefficient radio resource allocation in response to varying frame size. For example, the sources for the latency spikes may include queuing delay, time-varying radio environments, time-varying frame sizes, among others. Tools that can help to remove latency spikes are beneficial to enable better 5G support for this type of traffic.

In addition to bounded latency requirements, applications like XR and cloud gaming also require a high rate of transmission. This can be seen from the large frame sizes originated from this type of traffic. The typical frame sizes may range from tens of kilobytes to hundreds of kilobytes. The frame arrival rates may be 60 or 120 frames per second (fps). As a concrete example, a frame size of 100 kilobytes and a frame arrival rate of 120 fps can lead to a rate requirement of 95.8 Mbps.

A large video frame is usually fragmented into smaller Internet Protocol (IP) packets and transmitted as several transport blocks (TBs) over several TTIs in RAN. FIGURE 2 illustrates an example of the cumulative distribution functions of the number of transport blocks required to deliver a video frame with size ranging from 20 KB to 300 KB. For example, FIGURE 2 shows that for delivering the frames with a size of 200 KB each, the median number of needed TBs is 5.

FIGURE 3 illustrates XR traffic characteristics compared to Voice Over IP (VoIP) and Web-browsing. As can be seen from FIGURE 3, the characteristics of XR traffic arrival are quite distinct from typical web-browsing and VoIP traffic. It is well expected that the arrival time is quasi-periodic and largely predictable as VoIP. However, its data size is an order of magnitude larger than VoIP, as discussed above. In addition, similar to web-browsing, the data size is different at every application Packet Data Unit (PDU) arrival instance due to dynamics of contents and human motion.

As mentioned above, many XR applications will generate traffic periodically with a variable size. When the application packet enters the internet, the initial packet may be transmitted as a single PDU in the network or may be segmented into several PDUs. One application packet could, for instance, correspond to one or several IP packets.

IP packets will arrive to the Packet Data Convergence Protocol (PDCP) layer (i.e., PDCP Service Data Units (SDUs)), and the PDCP layer will create PDCP PDUs and will deliver them to lower layers. When an IP packet arrives to PDCP, the PDCP layer starts a PDCP discard timer. When this timer expires, the PDCP discards the PDCP SDU as well as the corresponding PDCP Data PDU. If the PDCP PDU was delivered to lower layers, PDCP indicates the discard to lower layers. Lower layers such as, for example, Radio Link Control (RLC) will discard the PDCP PDUs (RLC SDU) if these RLC SDU or any segment of the RLC SDU has not yet been transmitted to lower layers.

As discussed above, an application PDU such as, for example, a video frame, is divided into multiple IP packets. All these IP packets which belong to one video frame can be defined as PDU Set.

RLC Modes and Operation

An RLC entity can be configured with three different modes: Transparent Mode (TM), Acknowledged Mode (AM), and Unacknowledged Mode (UM). The typical RLC modes used to transmit user data are AM or UM. The RLC mode is configured by the network using a Radio Resource Control (RRC) reconfiguration message and, typically, once configured, the RLC mode does not change throughout the session. One of the major differences between RLC AM and UM modes is that the RLC AM mode includes mechanisms to control successful or unsuccessful reception of RLC SDUs or RLC SDU segments by the receiver and to perform retransmissions when data is not successfully received by the receiver.

When RLC AM Mode is configured, the transmitter entity will perform retransmissions when data is not successfully received by the receiver. The receiver will typically inform the transmitter about the successfully received (positive acknowledgement - ACK) or unsuccessfully received (negative acknowledgement - NACK) RLC SDUs or RLC SDU segments. In NR, this information is carried in the RLC STATUS PDU.

One particularity of RLC AM mode is that the transmitter will re-transmit RLC SDUs or its segments until the RLC SDU or its segments have been successfully received by the receiver or when the maximum number of RLC retransmissions has been reached. When the maximum number of RLC retransmissions is reached, the User Equipment (UE) declares a radio link failure (RLF) and the RRC connection is re-established. The re-establishment allows to indicate to the network that the UE has a link level problem, and it also allows to reconfigure the UE with a new configuration more suitable to the properties of the link the user is experiencing.

The maximum number of RLC re-transmissions is a parameter configured by the RRC Information Element (IE) “maxRetxThreshold” . This parameter applies until a new RRC reconfiguration message is received by the UE with a new value.

RLC Headers

For RLC UM Mode, the Unacknowledge Mode Data (UMD) PDU consists of a Data Field and a UMD PDU header. The UMD PDU header can contain different information depending on whether the UMD PDU contains a complete RLC SDU or RLC SDU Segment(s). Thus, different UMD PDU formats are possible. The UMD PDU header always carries the Segmentation Info (SI) field and can additionally carry one or more of the following elements: the Sequence Number (SN), the Segment Offset (SO), and Reserved (R) bit.

For RLC AM, the Acknowledge Mode Data (AMD) PDU consist of a data field and an AMD PDU header. The first bit of the AMD PDU header is a Data/Control (D/C) bit. Depending on this bit, different formats are defined. For data, the header contains one or more of the following fields: the D/C field, a Polling (P) bit, a SN field, a SI field, a SO field, and R bit field. When the D/C field is set to ‘C’, the AMD PDU is then a RLC Control PDU. RLC control PDU header consists of a D/C and a Control PDU Type (CPT) field. In current RLC version vl8.0.0, the only standardized CPT is the STATUS PDU, which provides ACK/NACK information. The STATUS PDU payload consists of one ACK_SN and one El, zero or more sets of a NACK_SN, an El, an E2 and an E3, and possibly a pair of a SOstart and a SOend or a NACK range field for each NACK_SN. The El field indicates whether or not a set of NACK_SN, El, E2 and E3 follows. The E2 field indicates whether or not a set of SOstart and SOend follows. The E3 field indicates whether or not information about a continuous sequence of RLC SDUs that have not been received follows. FIGURE 4 illustrates one example format of an AMD PDU.

There currently exist certain challenge(s), however. Specifically, for example, there are two main problems. The first is that there is one RLC entity per Data Radio Bearer (DRB) and one RLC entity can only be configured with one RLC Mode. Thus, all the packets going through the said DRB, regardless of the originating flow, will be transmitted or received by the associated RLC entity using the same RLC Mode. This sets a limitation when, for example, mapping flows from different services into the same DRB. In this case, these flows may have different requirements. One of the flows could have large packet delay budget (PDB) while another flow has a short budget. Thus, while the first flow could be configured with RLC AM to maximize its successful transmission, the second flow could be configured with no retransmissions due to the short delay budget. Another case could be that, due to queues building up in the network, there is no time or only limited time to do RLC retransmissions. This is, however, a dynamic situation.

The second problem is that, in RLC AM Mode, when the maximum number of RLC retransmissions is reached, the UE starts an RRC connection re-establishment. This creates a long user plane break. While, in general, a re-establishment may be desired for certain types of traffic and situations, it may be more suitable to lose the data but not re-establish the RRC connection. For data with bounded latency, there might not be opportunity to do RLC retransmissions, but if there are retransmissions and the data is not received within its PDB, then it is better to discard the data and to not re-establish the RRC connection.

SUMMARY

Certain aspects of the disclosure and their embodiments may provide solutions to these or other challenges. For example, methods and systems are provided for enabling the network and UE to perform fewer retransmissions than the maximum number of RLC retransmissions configured by the network even if the RLC PDU is not successfully received by the receiver RLC entity. When that happens, an RLF failure for reaching the maximum number of RLC retransmissions is not triggered. According to certain embodiments, this is achieved by updating the state variables of the RLC transmitting and receiving window.

According to certain embodiments, a method performed by a receiving radio node for RLC transmissions includes receiving, from a transmitting node, information indicating that at least one RLC PDU is not to be retransmitted by the transmitting radio node. The receiving radio node takes at least one action associated with the at least one RLC PDU not to be retransmitted to the receiving radio node. For example, taking the at least one action includes updating at least one parameter associated with an RLC receiving window.

According to certain embodiments, a receiving radio node for RLC transmission is configured to receive, from a transmitting node, information indicating that at least one RLC PDU is not to be retransmitted by the transmitting radio node. The receiving radio node is configured to take at least one action associated with the at least one RLC PDU not to be retransmitted to the receiving radio node. For example, when taking the at least one action, the receiving radio node is configured to update at least one parameter associated with an RLC receiving window.

According to certain embodiments, a method performed by a transmitting radio node for RLC transmissions includes determining that at least one RLC PDU is not to be retransmitted by the transmitting radio node. The transmitting radio node takes at least one action to prevent a retransmission of the at least one RLC PDU to a receiving radio node. For example, when taking the at least one action, the transmitting radio node transmits, to the receiving radio node, a message indicating that the at least one RLC PDU is not to be retransmitted. The transmitting radio node updates at least one parameter associated with an RLC transmitting window.

According to certain embodiments, a transmitting radio node for RLC transmissions is configured to determine that at least one RLC PDU is not to be retransmitted by the transmitting radio node. The transmitting radio node is configured to take at least one action to prevent a retransmission of the at least one RLC PDU to a receiving radio node. For example, when taking the at least one action, the transmitting radio node is configured to transmit, to the receiving radio node, a message indicating that the at least one RLC PDU is not to be retransmitted. The transmitting radio node is configured to update at least one parameter associated with an RLC transmitting window.

Certain embodiments may provide one or more of the following technical advantage(s). For example, certain embodiments may provide a technical advantage of enabling configuration of RLC AM Mode while not having to retransmit PLC PDUs if, for example, the PDB for the associated RLC SDU has been exceeded.

Other advantages may be readily apparent to one having skill in the art. Certain embodiments may have none, some, or all of the recited advantages.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the disclosed embodiments and their features and advantages, reference is now made to the following description, taken in conjunction with the accompanying drawings, in which:

FIGURE 1 illustrates an example of frame latency measured over RAN), excluding application & core network latencies;

FIGURE 2 illustrates an example of the cumulative distribution functions of the number of transport blocks required to deliver a video frame with size ranging from 20 KB to 300 KB;

FIGURE 3 illustrates XR traffic characteristics compared to Voice Over IP (VoIP) and Web-browsing;

FIGURE 4 illustrates one example format of an AMD PDU;

FIGURE 5 illustrates the case in which a new Control PDU indicates the RLC SN associated to the lowest end of the window, when the SN length is 12-bits, according to certain embodiments;

FIGURE 6 illustrates an example case in which 18-bit SN length is configured and the new Control PDU indicates multiple RLC SN and a SN range, according to certain embodiments;

FIGURE 7 illustrates a Control PDU combining STATUS PDU and RLC SDU skipping information, according to certain embodiments;

FIGURE 8 illustrates a Control PDU using the “R”-bit after the ACK_SN to indicate whether a RLC SN + E-fields follow, according to certain embodiments;

FIGURE 9 illustrates an example of AMD PDU when using 18 bit SN without SO, according to certain embodiments;

FIGURE 10 illustrates a modified format of AMD PDU with 12 bits SN with SO, according to certain embodiments;

FIGURE 11 illustrates an example communication system, according to certain embodiments;

FIGURE 12 illustrates an example UE, according to certain embodiments;

FIGURE 13 illustrates an example network node, according to certain embodiments;

FIGURE 14 illustrates a virtualization environment in which functions implemented by some embodiments may be virtualized, according to certain embodiments;

FIGURE 15 illustrates an example method by a transmitting radio node for RLC transmissions, according to certain embodiments;

FIGURE 16 illustrates an example method by a receiving radio node for RLC transmissions, according to certain embodiments;

FIGURE 17 illustrates another example method by a receiving radio node for RLC transmissions, according to certain embodiments;

FIGURE 18 illustrates another example method by a transmitting radio node for RLC transmissions, according to certain embodiments;

FIGURE 19 illustrates a method performed by a receiving radio node for RLC transmissions, according to certain embodiments; and

FIGURE 20 illustrates a method performed by a transmitting radio node for RLC transmissions, according to certain embodiments.

DETAILED DESCRIPTION

Some of the embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. Embodiments are provided by way of example to convey the scope of the subject matter to those skilled in the art.

As used herein, ‘node’ can be a network node or a UE. Examples of network nodes are NodeB, base station (BS), multi-standard radio (MSR) radio node such as MSR BS, eNodeB (eNB), gNodeB (gNB), Master eNB (MeNB), Secondary eNB (SeNB), integrated access backhaul (IAB) node, network controller, radio network controller (RNC), base station controller (BSC), relay, donor node controlling relay, base transceiver station (BTS), Central Unit (e.g. in a gNB), Distributed Unit (e.g. in a gNB), Baseband Unit, Centralized Baseband, C-RAN, access point (AP), transmission points, transmission nodes, Remote Radio Unit (RRU), Remote Radio Head (RRH), nodes in distributed antenna system (DAS), core network node (e.g. Mobile Switching Center (MSC), Mobility Management Entity (MME), etc.), Operations & Maintenance (O&M), Operations Support System (OSS), Self-Organizing Network (SON), positioning node (e.g. E- SMLC), etc.

Another example of a node is user equipment (UE), which is a non-limiting term and refers to any type of wireless device communicating with a network node and/or with another UE in a cellular or mobile communication system. Examples of UE are target device, device to device (D2D) UE, vehicular to vehicular (V2V), machine type UE, MTC UE or UE capable of machine to machine (M2M) communication, Personal Digital Assistant (PDA), Tablet, mobile terminals, smart phone, laptop embedded equipment (LEE), laptop mounted equipment (LME), Unified Serial Bus (USB) dongles, etc.

In some embodiments, generic terminology, “radio network node” or simply “network node”, is used. It can be any kind of network node which may comprise base station, radio base station, base transceiver station, base station controller, network controller, evolved Node B (eNB), Node B, gNodeB (gNB), relay node, access point, radio access point, Remote Radio Unit (RRU) Remote Radio Head (RRH), Central Unit (e.g. in a gNB), Distributed Unit (e.g. in a gNB), Baseband Unit, Centralized Baseband, C-RAN, access point (AP), etc.

The term radio access technology (RAT), may refer to any RAT such as, for example, Universal Terrestrial Radio Access Network (UTRA), Evolved Universal Terrestrial Radio Access Network (E-UTRA), narrow band internet of things (NB-IoT), WiFi, Bluetooth, next generation RAT, NR, 4G, 5G, etc. Any of the equipment denoted by the terms node, network node or radio network node may be capable of supporting a single or multiple RATs.

Each SSB carries New Radio-Primary Synchronization Signal (NR-PSS), New RadioSecondary Synchronization Signal (NR-SSS) and New Radio-Physical Broadcast Channel (NR- PBCH) in four successive symbols. One or multiple Synchronization Signal Blocks (SSBs) are transmitted in one SSB burst which is repeated with certain periodicity such as, for example, 5 ms, 10 ms, 20 ms, 40 ms, 80 ms, and 160 ms. The UE is configured with information about SSB on cells of certain carrier frequency by one or more SS/PBCH block measurement timing configuration (SMTC) configurations. The SMTC configuration comprising parameters such as SMTC periodicity, SMTC occasion length in time or duration, SMTC time offset with regard to reference time (e.g., serving cell’s SFN) etc. Therefore, SMTC occasion may also occur with certain periodicity (e.g., 5 ms, 10 ms, 20 ms, 40 ms, 80 ms, and 160 ms). Examples of uplink (UL) physical signals are reference signals such as Sounding Reference Signals (SRS), Demodulation Reference Signals (DMRS), etc. The term physical channel refers to any channel carrying higher layer information e.g. data, control etc. Examples of physical channels are Physical Broadcast Channel (PBCH), Physical Downlink Control Channel (PDCCH), Physical Downlink Shared Channel (PDSCH), Physical Uplink Shared Channel (PUSCH), Physical Uplink Control Channel (PUCCH), Physical Uplink Shared Channel (PUSCH), Short PUSCH (sPUCCH), Short PDSCH (sPDSCH), Short PUCCH (sPUCCH), Short PUSCH (sPUSCH), MTC PDCCH (MPDCCH), Narrowband PBCH (NPBCH), Narrowband PDCCH (NPDCCH), Narrowband PDSCH (NPDSCH), Narrowband PUSCH (NPUSCH), Enhanced PDCCH (E-PDCCH), etc.

The term time resource used herein may correspond to any type of physical resource or radio resource expressed in terms of length of time. Examples of time resources are: symbol, time slot, subframe, radio frame, TTI, interleaving time, slot, sub-slot, mini-slot, system frame number (SFN) cycle, hyper-SFN (H-SFN) cycle etc.

According to certain embodiments, the network node and the UE may decide to not perform RLC retransmissions for a given RLC PDU when RLC AM mode is configured, even if the RLC PDU has not been successfully received by the receiver RLC entity According to various embodiments, this can be done using different mechanisms. These mechanisms will typically provide information about the RLC PDUs that are not going to be retransmitted so enable the transmitting and receiving RLC entities to update their RLC window.

According to particular embodiments described in more detail below, there may be three types of solution to provide information to the RLC entities that can be used to update the state variables of the RLC window.

Introducing a New Control PDU (e.g., RLC Advance Window)

According to certain embodiments, a new control PDU is introduced, which may be referred to as an RLC Advance Window. This new Control PDU is used to inform the RLC receiver or the transmitter entity that no more retransmissions are needed for one or more RLC PDUs. This may also result in the transmitting and receiving RLC windows being updated. For example, in a particular embodiment, the lower end of the RLC window may be moved forward.

In a particular embodiment, the new Control PDU is identified by a new CPT value, introduced for this purpose. Additionally, in various particular embodiments, the Control PDU may include one or more of the following: the RLC PDU(s) SN that do not need be retransmitted, lowest RLC PDU SN waiting for retransmission, lowest end of the RLC window, and/or SN range.

If the message indicates one or more RLC PDUs SN that do not need to be retransmitted, the RLC entity will ignore these RLC PDU SN or considered them as if they had been positively received. If the indicated RLC PDU SNs do belong to RLC SDUs not completely received, the receiving RLC entity will discard the already received RLC SDUs segments belonging to those incomplete RLC SDUs.

In a particular embodiment, when multiple RLC SDU SNs are indicated, the RLC Control PDU sets 1-bit such as, for example, the El-bit, to indicate that additional RLC SDU SNs are indicated.

In a particular embodiment, if the messages indicates the lowest end SN of the RLC window, the RLC transmitting entity will not retransmit those RLC PDUs SN that were pending of retransmission up to the indicated RLC PDU SN (included or up to the one before it) and will consider those RLC PDUs SN as if they were positively received by the receiver. If there were incomplete RLC SDUs (include or up to the one before the indicated SN), the receiving RLC entity will discard the already received RLC SDUs segments belonging to those incomplete RLC SDUs and will also consider those RLC SDUs (included or up to the one before the indicated RLC PDU SN) as if they were positively received. Those complete RLC SDUs waiting to be passed to higher layers, will then be passed to higher layer up (included or up to the one before the indicated RLC PDU SN).

It is noted that one RLC SDU can be equivalent to 1 or more RLC PDUs. In case the RLC SDU is segmented, then there will be more than one RLC PDU. However, if any RLC PDU associated to RLC SDU has not started to be transmitted, then there is no need to send any indication to the receiver. Also note that one RLC SDU has one SN and all RLC PDUs associated to the RLC SDU share the same SN.

FIGURE 5 illustrates the case in which a new Control PDU 100 indicates the RLC SN 102 associated to the lowest end of the window, when the SN length is 12-bits, according to certain embodiments.

FIGURE 6 illustrates an example Control PDU 200 in which 18 -bit SN length is configured and the new Control PDU indicates multiple RLC SN 202a, 202b, 202c, 202d, 202e, and 202f and a SN range 204, according to certain embodiments. The RLC control PDU header can consist of one or more RLC SN 202c and one El 206a and one E3 206b, and possibly a SN range field 204 for each RLC SN.

When the field El 206a is set, another set of RLC SN 202f, El 206c, and E3 206d follow. When E3 206d is set, it means that a SN range 204follows for this indicated RLC SN 202f.

Introducing a New Control PDU- Extending Current STATUS PDU

According to certain embodiments described above, a new CPT value is used. However, in a particular embodiment, a solution is built on top of the current STATUS Report. FIGURE 7 illustrates an exemplary new Control PDU 300 combining STATUS PDU and RLC SDU skipping information, according to certain embodiments. For example, a new field such as, for example, E4 302, is introduced to indicate that a set of RLC SN, El, E2, E3, and E4 follows. When E4 is set, one RLC SN, one or more of El, E2, E3, E4 would follow, in a particular embodiment. Those present fields (one or more of El, E2, E3, E4) would be redefined.

Thus, in a particular embodiment, the following fields would indicate one or more RLC

SN, the corresponding E-fields, and possibly a SN range field for each RLC SN.

When the field such as, for example, El, is set, another set of RLC SN, El, and another E- field such as, for example, E3, follow. When the field E3 is set, for example, it means that a SN range follows for this indicated RLC SN.

FIGURE 8 illustrates another alternative new Control PDU 400 that uses the “R”-bit after the ACK_SN to indicate whether a RLC SN + E-fields follow, according to certain embodiments. Thus, for exmaple, when El is set to 0 and the new field such as, for example, E4 802, is set to 1, then one RLC SN, and one or more of the E-fields follow, as explained above.

Introducing a new Data PDU

According to certain embodiments, instead of using control PDU, it is also possible to extend existing data PDU or introduce new data PDU to indicate RLC SN to the receiving RLC entity. FIGURE 9 illustrates an example Control AMD PDU 500 that uses 18 bit SN 502 without

SO, according to certain embodiments. The two reserved bits can be used to indicate RLC_SN 504 is followed after SN 502 of the data. Then 18 bits of RLC_SN 504 are followed before data 506. The RLC_SN 504 will be used for the same purpose as one in the new control PDU. If the reserved bits are not flagged, i.e. 00, there are no RNC_SN followed so the legacy AMD PDU 500 is transmitted.

If there are no reserved bits, another new data PDU format can be introduced. For example, FIGURE 10 shows the modified format of AMD PDU 600 with 12 bits SN with now SO. RLC_SN indication bit (RN) 602 is added after SN 604 and that indicates if RLC_SN 606 is followed or not. Once that bit is flagged, RLC SN 606 is added. Otherwise, there is no RLC SN bits added before data 608.

Triggering Mechanisms for Improved RLC Control PDU and RLC AMD PDU and RLC transmitter and Receiver Behavior

According to previous methods and techniques, when the PDCP entity indicates to lower layers (e.g., RLC) to discard a certain PDCP PDU (e.g., an RLC SDU), the RLC entity discards the associated RLC SDU if the complete or a segment of the RLC SDU was not already transmitted.

According to certain embodiments described herein, however, when the network configures the new RLC Control PDU, the behavior can be changed in one or more of the following ways:

1) When the PDCP entity indicates to discard a PDCP PDU or PDCP PDUs related to a PDU Set, the transmitting RLC entity performs one or more of the following: a. The transmitting RLC entity discards the RLC SDUs associated to the said PDCP PDUs, and the transmitting RLC entity will stop any ongoing transmissions for the RLC SDUs or any of their segments. b. The transmitting RLC entity builds the new RLC Control PDU providing an indication of the RLC SDUs which the transmitter is discarding. c. The transmitting RLC entity considers those RLC SDUs as if the RLC SDUs had been positively acknowledged. d. The transmitting RLC entity may update the TX_Next_Ack taking into account the said RLC SDUs which were considered as positively acknowledged. e. The transmitting RLC entity does not send an indication to the upper layers of successful delivery for the said RLC SDUs. f. The transmitting RLC entity does not perform any further retransmissions of those RLC SDUs.

2) When the receiving RLC entity gets this indication, the receiving RLC entity performs one or more of: a. If the indication provided the RLC PDU(s) SN that do not need be retransmitted, i. the receiving RLC entity considers the RLC SDUs indicated in the message as if these RLC PDUs has been placed in the reception buffer, which results in that the receiving RLC entity will update the receiver window variables accordingly. b. If the indication provided the lowest RLC PDU SN waiting for retransmission or lowest end of the RLC window, i. the receiving RLC entity considers the RLC SDUs up to the indicated SN as if these RLC PDUs has been placed in the reception buffer, which results in that the receiving RLC entity will update the receiver window variables accordingly. c. If the indication provided a SN range, i. the receiving RLC entity considers the RLC SDUs within the range as if these RLC PDUs has been placed in the reception buffer, which results in that the receiving RLC entity will update the receiver window variables accordingly. d. The receiving RLC entity discards the RLC SDU segments, if any, of the affected RLC SDUs SN.

In another particular embodiment, a network can introduce new RLC parameters to configure the triggering of the new RLC control PDU instead of relying on PDCP discarding operation. For example, a network configures a threshold of RLC AM retransmission attempt (R thr) which can be smaller than the maximum RLC AM retransmission which is used for RLC failure to reestablish RRC connection. Once the number of RLC AM retransmission reaches R thr, the transmitting/receiving RLC entity follows the procedures of 2) and 3) above.

In another particular embodiment, instead of or in addition to R thr, a network configures the maximum delay of RLC transmission (L thr), which can be measured from the first initial RLC transmission timing to the reception of its ACK. Once the L thr is reached for a RLC SDU, the transmitting/receiving RLC entity follows the procedures of 2) and 3) above.

In yet another particular embodiment, if a network has configured to use dependency between flows/packets, then if dependencies are identified between packets that the RLC SDUs are associated to (e.g., PDU Sets) and that has been discarded, not received, or indicated to not be retransmitted, the RLC entity may follow the procedures of 2) and 3) above.

In yet another particular embodiment, if a network is configured to use PDU Set Importance (PSI) levels to differentiate between high and low importance packets in a flow, and if PSI levels are identified, the transmitting RLC entity triggers a RLC control PDU after X retransmission attempts associated with PSI level Y. The network may, in a particular embodiment, configure how many re-transmission attempts is possible for each PSI level.

FIGURE 11 shows an example of a communication system 700 in accordance with some embodiments. In the example, the communication system 700 includes a telecommunication network 702 that includes an access network 704, such as a radio access network (RAN), and a core network 706, which includes one or more core network nodes 708. The access network 704 includes one or more access network nodes, such as network nodes 710a and 710b (one or more of which may be generally referred to as network nodes 710), or any other similar 3rd Generation Partnership Project (3 GPP) access node or non-3GPP access point. The network nodes 710 facilitate direct or indirect connection of user equipment (UE), such as by connecting UEs 712a, 712b, 712c, and 712d (one or more of which may be generally referred to as UEs 712) to the core network 706 over one or more wireless connections.

Example wireless communications over a wireless connection include transmitting and/or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and/or other types of signals suitable for conveying information without the use of wires, cables, or other material conductors. Moreover, in different embodiments, the communication system 700 may include any number of wired or wireless networks, network nodes, UEs, and/or any other components or systems that may facilitate or participate in the communication of data and/or signals whether via wired or wireless connections. The communication system 700 may include and/or interface with any type of communication, telecommunication, data, cellular, radio network, and/or other similar type of system.

The UEs 712 may be any of a wide variety of communication devices, including wireless devices arranged, configured, and/or operable to communicate wirelessly with the network nodes 710 and other communication devices. Similarly, the network nodes 710 are arranged, capable, configured, and/or operable to communicate directly or indirectly with the UEs 712 and/or with other network nodes or equipment in the telecommunication network 702 to enable and/or provide network access, such as wireless network access, and/or to perform other functions, such as administration in the telecommunication network 702.

In the depicted example, the core network 706 connects the network nodes 710 to one or more hosts, such as host 716. These connections may be direct or indirect via one or more intermediary networks or devices. In other examples, network nodes may be directly coupled to hosts. The core network 706 includes one more core network nodes (e.g., core network node 708) that are structured with hardware and software components. Features of these components may be substantially similar to those described with respect to the UEs, network nodes, and/or hosts, such that the descriptions thereof are generally applicable to the corresponding components of the core network node 708. Example core network nodes include functions of one or more of a Mobile Switching Center (MSC), Mobility Management Entity (MME), Home Subscriber Server (HSS), Access and Mobility Management Function (AMF), Session Management Function (SMF), Authentication Server Function (AUSF), Subscription Identifier De-concealing function (SIDF), Unified Data Management (UDM), Security Edge Protection Proxy (SEPP), Network Exposure Function (NEF), and/or a User Plane Function (UPF).

The host 716 may be under the ownership or control of a service provider other than an operator or provider of the access network 704 and/or the telecommunication network 702 and may be operated by the service provider or on behalf of the service provider. The host 716 may host a variety of applications to provide one or more service. Examples of such applications include live and pre-recorded audio/video content, data collection services such as retrieving and compiling data on various ambient conditions detected by a plurality of UEs, analytics functionality, social media, functions for controlling or otherwise interacting with remote devices, functions for an alarm and surveillance center, or any other such function performed by a server.

As a whole, the communication system 700 of FIGURE 11 enables connectivity between the UEs, network nodes, and hosts. In that sense, the communication system may be configured to operate according to predefined rules or procedures, such as specific standards that include, but are not limited to: Global System for Mobile Communications (GSM); Universal Mobile

Telecommunications System (UMTS); Long Term Evolution (LTE), and/or other suitable 2G, 3G, 4G, 5G standards, or any applicable future generation standard (e.g., 6G); wireless local area network (WLAN) standards, such as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards (WiFi); and/or any other appropriate wireless communication standard, such as the Worldwide Interoperability for Microwave Access (WiMax), Bluetooth, Z-Wave, Near Field Communication (NFC) ZigBee, LiFi, and/or any low-power wide-area network (LPWAN) standards such as LoRa and Sigfox.

In some examples, the telecommunication network 702 is a cellular network that implements 3GPP standardized features. Accordingly, the telecommunications network 702 may support network slicing to provide different logical networks to different devices that are connected to the telecommunication network 702. For example, the telecommunications network 702 may provide Ultra Reliable Low Latency Communication (URLLC) services to some UEs, while providing Enhanced Mobile Broadband (eMBB) services to other UEs, and/or Massive Machine Type Communication (mMTC)/Massive loT services to yet further UEs.

In some examples, the UEs 712 are configured to transmit and/or receive information without direct human interaction. For instance, a UE may be designed to transmit information to the access network 704 on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the access network 704. Additionally, a UE may be configured for operating in single- or multi-RAT or multi -standard mode. For example, a UE may operate with any one or combination of Wi-Fi, NR (New Radio) and LTE, i.e. being configured for multi-radio dual connectivity (MR-DC), such as E-UTRAN (Evolved-UMTS Terrestrial Radio Access Network) New Radio - Dual Connectivity (EN-DC).

In the example, the hub 714 communicates with the access network 704 to facilitate indirect communication between one or more UEs (e.g., UE 712c and/or 712d) and network nodes (e.g., network node 710b). In some examples, the hub 714 may be a controller, router, content source and analytics, or any of the other communication devices described herein regarding UEs. For example, the hub 714 may be a broadband router enabling access to the core network 706 for the UEs. As another example, the hub 714 may be a controller that sends commands or instructions to one or more actuators in the UEs. Commands or instructions may be received from the UEs, network nodes 710, or by executable code, script, process, or other instructions in the hub 714. As another example, the hub 714 may be a data collector that acts as temporary storage for UE data and, in some embodiments, may perform analysis or other processing of the data. As another example, the hub 714 may be a content source. For example, for a UE that is a VR headset, display, loudspeaker or other media delivery device, the hub 714 may retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, which the hub 714 then provides to the UE either directly, after performing local processing, and/or after adding additional local content. In still another example, the hub 714 acts as a proxy server or orchestrator for the UEs, in particular in if one or more of the UEs are low energy loT devices.

The hub 714 may have a constant/persistent or intermittent connection to the network node 710b. The hub 714 may also allow for a different communication scheme and/or schedule between the hub 714 and UEs (e.g., UE 712c and/or 712d), and between the hub 714 and the core network 706. In other examples, the hub 714 is connected to the core network 706 and/or one or more UEs via a wired connection. Moreover, the hub 714 may be configured to connect to an M2M service provider over the access network 704 and/or to another UE over a direct connection. In some scenarios, UEs may establish a wireless connection with the network nodes 710 while still connected via the hub 714 via a wired or wireless connection. In some embodiments, the hub 714 may be a dedicated hub - that is, a hub whose primary function is to route communications to/from the UEs from/to the network node 710b. In other embodiments, the hub 714 may be a nondedicated hub - that is, a device which is capable of operating to route communications between the UEs and network node 710b, but which is additionally capable of operating as a communication start and/or end point for certain data channels.

FIGURE 12 shows a UE 800, which may be an embodiment of the UE 112 of FIGURE 11, in accordance with some embodiments. As used herein, a UE refers to a device capable, configured, arranged and/or operable to communicate wirelessly with network nodes and/or other UEs. Examples of a UE include, but are not limited to, a smart phone, mobile phone, cell phone, voice over IP (VoIP) phone, wireless local loop phone, desktop computer, personal digital assistant (PDA), wireless cameras, gaming console or device, music storage device, playback appliance, wearable terminal device, wireless endpoint, mobile station, tablet, laptop, laptop-embedded equipment (LEE), laptop-mounted equipment (LME), smart device, wireless customer-premise equipment (CPE), vehicle-mounted or vehicle embedded/integrated wireless device, etc. Other examples include any UE identified by the 3rd Generation Partnership Project (3GPP), including a narrow band internet of things (NB-IoT) UE, a machine type communication (MTC) UE, and/or an enhanced MTC (eMTC) UE.

A UE may support device-to-device (D2D) communication, for example by implementing a 3GPP standard for sidelink communication, Dedicated Short-Range Communication (DSRC), vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), or vehicle-to-everything (V2X). In other examples, a UE may not necessarily have a user in the sense of a human user who owns and/or operates the relevant device. Instead, a UE may represent a device that is intended for sale to, or operation by, a human user but which may not, or which may not initially, be associated with a specific human user (e.g., a smart sprinkler controller). Alternatively, a UE may represent a device that is not intended for sale to, or operation by, an end user but which may be associated with or operated for the benefit of a user (e.g., a smart power meter).

The UE 800 includes processing circuitry 802 that is operatively coupled via a bus 804 to an input/output interface 806, a power source 808, a memory 810, a communication interface 812, and/or any other component, or any combination thereof. Certain UEs may utilize all or a subset of the components shown in FIGURE 12. The level of integration between the components may vary from one UE to another UE. Further, certain UEs may contain multiple instances of a component, such as multiple processors, memories, transceivers, transmitters, receivers, etc.

The processing circuitry 802 is configured to process instructions and data and may be configured to implement any sequential state machine operative to execute instructions stored as machine-readable computer programs in the memory 810. The processing circuitry 802 may be implemented as one or more hardware-implemented state machines (e.g., in discrete logic, field- programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), etc.); programmable logic together with appropriate firmware; one or more stored computer programs, general -purpose processors, such as a microprocessor or digital signal processor (DSP), together with appropriate software; or any combination of the above. For example, the processing circuitry 802 may include multiple central processing units (CPUs).

In the example, the input/output interface 806 may be configured to provide an interface or interfaces to an input device, output device, or one or more input and/or output devices. Examples of an output device include a speaker, a sound card, a video card, a display, a monitor, a printer, an actuator, an emitter, a smartcard, another output device, or any combination thereof. An input device may allow a user to capture information into the UE 800. Examples of an input device include a touch-sensitive or presence-sensitive display, a camera (e g., a digital camera, a digital video camera, a web camera, etc.), a microphone, a sensor, a mouse, a trackball, a directional pad, a trackpad, a scroll wheel, a smartcard, and the like. The presence-sensitive display may include a capacitive or resistive touch sensor to sense input from a user. A sensor may be, for instance, an accelerometer, a gyroscope, a tilt sensor, a force sensor, a magnetometer, an optical sensor, a proximity sensor, a biometric sensor, etc., or any combination thereof. An output device may use the same type of interface port as an input device. For example, a Universal Serial Bus (USB) port may be used to provide an input device and an output device.

In some embodiments, the power source 808 is structured as a battery or battery pack. Other types of power sources, such as an external power source (e g., an electricity outlet), photovoltaic device, or power cell, may be used. The power source 808 may further include power circuitry for delivering power from the power source 808 itself, and/or an external power source, to the various parts of the UE 800 via input circuitry or an interface such as an electrical power cable. Delivering power may be, for example, for charging of the power source 808. Power circuitry may perform any formatting, converting, or other modification to the power from the power source 808 to make the power suitable for the respective components of the UE 800 to which power is supplied.

The memory 810 may be or be configured to include memory such as random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), magnetic disks, optical disks, hard disks, removable cartridges, flash drives, and so forth. In one example, the memory 810 includes one or more application programs 814, such as an operating system, web browser application, a widget, gadget engine, or other application, and corresponding data 816. The memory 810 may store, for use by the UE 800, any of a variety of various operating systems or combinations of operating systems.

The memory 810 may be configured to include a number of physical drive units, such as redundant array of independent disks (RAID), flash memory, USB flash drive, external hard disk drive, thumb drive, pen drive, key drive, high-density digital versatile disc (HD-DVD) optical disc drive, internal hard disk drive, Blu-Ray optical disc drive, holographic digital data storage (HDDS) optical disc drive, external mini-dual in-line memory module (DIMM), synchronous dynamic random access memory (SDRAM), external micro-DIMM SDRAM, smartcard memory such as tamper resistant module in the form of a universal integrated circuit card (UICC) including one or more subscriber identity modules (SIMs), such as a USIM and/or ISIM, other memory, or any combination thereof. The UICC may for example be an embedded UICC (eUICC), integrated UICC (iUICC) or a removable UICC commonly known as ‘SIM card.’ The memory 810 may allow the UE 800 to access instructions, application programs and the like, stored on transitory or non-transitory memory media, to off-load data, or to upload data. An article of manufacture, such as one utilizing a communication system may be tangibly embodied as or in the memory 810, which may be or comprise a device-readable storage medium.

The processing circuitry 802 may be configured to communicate with an access network or other network using the communication interface 812. The communication interface 812 may comprise one or more communication subsystems and may include or be communicatively coupled to an antenna 822. The communication interface 812 may include one or more transceivers used to communicate, such as by communicating with one or more remote transceivers of another device capable of wireless communication (e.g., another UE or a network node in an access network). Each transceiver may include a transmitter 818 and/or a receiver 820 appropriate to provide network communications (e.g., optical, electrical, frequency allocations, and so forth). Moreover, the transmitter 818 and receiver 820 may be coupled to one or more antennas (e.g., antenna 822) and may share circuit components, software or firmware, or alternatively be implemented separately.

In the illustrated embodiment, communication functions of the communication interface 812 may include cellular communication, Wi-Fi communication, LPWAN communication, data communication, voice communication, multimedia communication, short-range communications such as Bluetooth, near-field communication, location-based communication such as the use of the global positioning system (GPS) to determine a location, another like communication function, or any combination thereof. Communications may be implemented in according to one or more communication protocols and/or standards, such as IEEE 802.11, Code Division Multiplexing Access (CDMA), Wideband Code Division Multiple Access (WCDMA), GSM, LTE, New Radio (NR), UMTS, WiMax, Ethernet, transmission control protocol/intemet protocol (TCP/IP), synchronous optical networking (SONET), Asynchronous Transfer Mode (ATM), QUIC, Hypertext Transfer Protocol (HTTP), and so forth.

Regardless of the type of sensor, a UE may provide an output of data captured by its sensors, through its communication interface 812, via a wireless connection to a network node. Data captured by sensors of a UE can be communicated through a wireless connection to a network node via another UE. The output may be periodic (e.g., once every 15 minutes if it reports the sensed temperature), random (e.g., to even out the load from reporting from several sensors), in response to a triggering event (e.g., when moisture is detected, an alert is sent), in response to a request (e.g., a user initiated request), or a continuous stream (e g., a live video feed of a patient).

As another example, a UE comprises an actuator, a motor, or a switch, related to a communication interface configured to receive wireless input from a network node via a wireless connection. In response to the received wireless input the states of the actuator, the motor, or the switch may change. For example, the UE may comprise a motor that adjusts the control surfaces or rotors of a drone in flight according to the received input or to a robotic arm performing a medical procedure according to the received input.

A UE, when in the form of an Internet of Things (loT) device, may be a device for use in one or more application domains, these domains comprising, but not limited to, city wearable technology, extended industrial application and healthcare. Non-limiting examples of such an loT device are a device which is or which is embedded in: a connected refrigerator or freezer, a TV, a connected lighting device, an electricity meter, a robot vacuum cleaner, a voice controlled smart speaker, a home security camera, a motion detector, a thermostat, a smoke detector, a door/window sensor, a flood/moisture sensor, an electrical door lock, a connected doorbell, an air conditioning system like a heat pump, an autonomous vehicle, a surveillance system, a weather monitoring device, a vehicle parking monitoring device, an electric vehicle charging station, a smart watch, a fitness tracker, a head-mounted display for Augmented Reality (AR) or Virtual Reality (VR), a wearable for tactile augmentation or sensory enhancement, a water sprinkler, an animal- or itemtracking device, a sensor for monitoring a plant or animal, an industrial robot, an Unmanned Aerial Vehicle (UAV), and any kind of medical device, like a heart rate monitor or a remote controlled surgical robot. A UE in the form of an loT device comprises circuitry and/or software in dependence of the intended application of the loT device in addition to other components as described in relation to the UE 800 shown in FIGURE 12

As yet another specific example, in an loT scenario, a UE may represent a machine or other device that performs monitoring and/or measurements and transmits the results of such monitoring and/or measurements to another UE and/or a network node. The UE may in this case be an M2M device, which may in a 3GPP context be referred to as an MTC device. As one particular example, the UE may implement the 3 GPP NB-IoT standard. In other scenarios, a UE may represent a vehicle, such as a car, a bus, a truck, a ship and an airplane, or other equipment that is capable of monitoring and/or reporting on its operational status or other functions associated with its operation.

In practice, any number of UEs may be used together with respect to a single use case. For example, a first UE might be or be integrated in a drone and provide the drone’s speed information (obtained through a speed sensor) to a second UE that is a remote controller operating the drone. When the user makes changes from the remote controller, the first UE may adjust the throttle on the drone (e.g. by controlling an actuator) to increase or decrease the drone’ s speed. The first and/or the second UE can also include more than one of the functionalities described above. For example, a UE might comprise the sensor and the actuator, and handle communication of data for both the speed sensor and the actuators.

FIGURE 13 shows a network node 900, which may be an embodiment of the network node 110 of FIGURE 5, in accordance with some embodiments. As used herein, network node refers to equipment capable, configured, arranged and/or operable to communicate directly or indirectly with a UE and/or with other network nodes or equipment, in a telecommunication network.

Examples of network nodes include, but are not limited to, access points (APs) (e.g., radio access points), base stations (BSs) (e.g., radio base stations, Node Bs, evolved Node Bs (eNBs) and NR NodeBs (gNBs)).

Base stations may be categorized based on the amount of coverage they provide (or, stated differently, their transmit power level) and so, depending on the provided amount of coverage, may be referred to as femto base stations, pico base stations, micro base stations, or macro base stations. A base station may be a relay node or a relay donor node controlling a relay. A network node may also include one or more (or all) parts of a distributed radio base station such as centralized digital units and/or remote radio units (RRUs), sometimes referred to as Remote Radio Heads (RRHs). Such remote radio units may or may not be integrated with an antenna as an antenna integrated radio. Parts of a distributed radio base station may also be referred to as nodes in a distributed antenna system (DAS).

Other examples of network nodes include multiple transmission point (multi-TRP) 5G access nodes, multi-standard radio (MSR) equipment such as MSR BSs, network controllers such as radio network controllers (RNCs) or base station controllers (BSCs), base transceiver stations (BTSs), transmission points, transmission nodes, multi -cell/multi cast coordination entities (MCEs), Operation and Maintenance (O&M) nodes, Operations Support System (OSS) nodes, Self-Organizing Network (SON) nodes, positioning nodes (e.g., Evolved Serving Mobile Location Centers (E-SMLCs)), and/or Minimization of Drive Tests (MDTs).

The network node 900 includes a processing circuitry 902, a memory 904, a communication interface 906, and a power source 908. The network node 900 may be composed of multiple physically separate components (e.g., a NodeB component and a RNC component, or a BTS component and a BSC component, etc.), which may each have their own respective components. In certain scenarios in which the network node 900 comprises multiple separate components (e.g., BTS and BSC components), one or more of the separate components may be shared among several network nodes. For example, a single RNC may control multiple NodeBs. In such a scenario, each unique NodeB and RNC pair, may in some instances be considered a single separate network node. In some embodiments, the network node 900 may be configured to support multiple radio access technologies (RATs). In such embodiments, some components may be duplicated (e.g., separate memory 904 for different RATs) and some components may be reused (e.g., a same antenna 910 may be shared by different RATs). The network node 900 may also include multiple sets of the various illustrated components for different wireless technologies integrated into network node 900, for example GSM, WCDMA, LTE, NR, WiFi, Zigbee, Z-wave, LoRaWAN, Radio Frequency Identification (RFID) or Bluetooth wireless technologies. These wireless technologies may be integrated into the same or different chip or set of chips and other components within network node 900.

The processing circuitry 902 may comprise a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application-specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software and/or encoded logic operable to provide, either alone or in conjunction with other network node 900 components, such as the memory 904, to provide network node 900 functionality.

In some embodiments, the processing circuitry 902 includes a system on a chip (SOC). In some embodiments, the processing circuitry 902 includes one or more of radio frequency (RF) transceiver circuitry 912 and baseband processing circuitry 914. In some embodiments, the radio frequency (RF) transceiver circuitry 912 and the baseband processing circuitry 914 may be on separate chips (or sets of chips), boards, or units, such as radio units and digital units. In alternative embodiments, part or all of RF transceiver circuitry 912 and baseband processing circuitry 914 may be on the same chip or set of chips, boards, or units.

The memory 904 may comprise any form of volatile or non-volatile computer-readable memory including, without limitation, persistent storage, solid-state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), mass storage media (for example, a hard disk), removable storage media (for example, a flash drive, a Compact Disk (CD) or a Digital Video Disk (DVD)), and/or any other volatile or non-volatile, non-transitory device-readable and/or computer-executable memory devices that store information, data, and/or instructions that may be used by the processing circuitry 902. The memory 904 may store any suitable instructions, data, or information, including a computer program, software, an application including one or more of logic, rules, code, tables, and/or other instructions capable of being executed by the processing circuitry 902 and utilized by the network node 900. The memory 904 may be used to store any calculations made by the processing circuitry 902 and/or any data received via the communication interface 906. In some embodiments, the processing circuitry 902 and memory 904 is integrated.

The communication interface 906 is used in wired or wireless communication of signaling and/or data between a network node, access network, and/or UE. As illustrated, the communication interface 906 comprises port(s)/terminal(s) 916 to send and receive data, for example to and from a network over a wired connection. The communication interface 906 also includes radio frontend circuitry 918 that may be coupled to, or in certain embodiments a part of, the antenna 910. Radio front-end circuitry 918 comprises filters 920 and amplifiers 922. The radio front-end circuitry 918 may be connected to an antenna 910 and processing circuitry 902. The radio frontend circuitry may be configured to condition signals communicated between antenna 910 and processing circuitry 902. The radio front-end circuitry 918 may receive digital data that is to be sent out to other network nodes or UEs via a wireless connection. The radio front-end circuitry 918 may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of filters 920 and/or amplifiers 922. The radio signal may then be transmitted via the antenna 910. Similarly, when receiving data, the antenna 910 may collect radio signals which are then converted into digital data by the radio front-end circuitry 918. The digital data may be passed to the processing circuitry 902. In other embodiments, the communication interface may comprise different components and/or different combinations of components.

In certain alternative embodiments, the network node 900 does not include separate radio front-end circuitry 918, instead, the processing circuitry 902 includes radio front-end circuitry and is connected to the antenna 910. Similarly, in some embodiments, all or some of the RF transceiver circuitry 912 is part of the communication interface 906. In still other embodiments, the communication interface 906 includes one or more ports or terminals 916, the radio front-end circuitry 918, and the RF transceiver circuitry 912, as part of a radio unit (not shown), and the communication interface 906 communicates with the baseband processing circuitry 914, which is part of a digital unit (not shown).

The antenna 910 may include one or more antennas, or antenna arrays, configured to send and/or receive wireless signals. The antenna 910 may be coupled to the radio front-end circuitry 918 and may be any type of antenna capable of transmitting and receiving data and/or signals wirelessly. In certain embodiments, the antenna 910 is separate from the network node 900 and connectable to the network node 900 through an interface or port.

The antenna 910, communication interface 906, and/or the processing circuitry 902 may be configured to perform any receiving operations and/or certain obtaining operations described herein as being performed by the network node. Any information, data and/or signals may be received from a UE, another network node and/or any other network equipment. Similarly, the antenna 910, the communication interface 906, and/or the processing circuitry 902 may be configured to perform any transmitting operations described herein as being performed by the network node. Any information, data and/or signals may be transmitted to a UE, another network node and/or any other network equipment.

The power source 908 provides power to the various components of network node 900 in a form suitable for the respective components (e.g., at a voltage and current level needed for each respective component). The power source 908 may further comprise, or be coupled to, power management circuitry to supply the components of the network node 900 with power for performing the functionality described herein. For example, the network node 900 may be connectable to an external power source (e.g., the power grid, an electricity outlet) via an input circuitry or interface such as an electrical cable, whereby the external power source supplies power to power circuitry of the power source 908. As a further example, the power source 908 may comprise a source of power in the form of a battery or battery pack which is connected to, or integrated in, power circuitry. The battery may provide backup power should the external power source fail.

Embodiments of the network node 900 may include additional components beyond those shown in FIGURE 13 for providing certain aspects of the network node’ s functionality, including any of the functionality described herein and/or any functionality necessary to support the subject matter described herein. For example, the network node 900 may include user interface equipment to allow input of information into the network node 900 and to allow output of information from the network node 900. This may allow a user to perform diagnostic, maintenance, repair, and other administrative functions for the network node 900.

FIGURE 14 is a block diagram illustrating a virtualization environment 1000 in which functions implemented by some embodiments may be virtualized.

In the present context, virtualizing means creating virtual versions of apparatuses or devices which may include virtualizing hardware platforms, storage devices and networking resources. As used herein, virtualization can be applied to any device described herein, or components thereof, and relates to an implementation in which at least a portion of the functionality is implemented as one or more virtual components. Some or all of the functions described herein may be implemented as virtual components executed by one or more virtual machines (VMs) implemented in one or more virtual environments 1000 hosted by one or more of hardware nodes, such as a hardware computing device that operates as a network node, UE, core network node, or host. Further, in embodiments in which the virtual node does not require radio connectivity (e.g., a core network node or host), then the node may be entirely virtualized.

Applications 1002 (which may alternatively be called software instances, virtual appliances, network functions, virtual nodes, virtual network functions, etc.) are run in the virtualization environment Q400 to implement some of the features, functions, and/or benefits of some of the embodiments disclosed herein.

Hardware 1004 includes processing circuitry, memory that stores software and/or instructions executable by hardware processing circuitry, and/or other hardware devices as described herein, such as a network interface, input/output interface, and so forth. Software may be executed by the processing circuitry to instantiate one or more virtualization layers 1006 (also referred to as hypervisors or virtual machine monitors (VMMs)), provide VMs 1008a and 1008b (one or more of which may be generally referred to as VMs 1008), and/or perform any of the functions, features and/or benefits described in relation with some embodiments described herein. The virtualization layer 1006 may present a virtual operating platform that appears like networking hardware to the VMs 1008.

The VMs 1008 comprise virtual processing, virtual memory, virtual networking or interface and virtual storage, and may be run by a corresponding virtualization layer 1006.

Different embodiments of the instance of a virtual appliance 1002 may be implemented on one or more of VMs 1008, and the implementations may be made in different ways. Virtualization of the hardware is in some contexts referred to as network function virtualization (NFV). NFV may be used to consolidate many network equipment types onto industry standard high volume server hardware, physical switches, and physical storage, which can be located in data centers, and customer premise equipment.

In the context of NFV, a VM 1008 may be a software implementation of a physical machine that runs programs as if they were executing on a physical, non-virtualized machine. Each of the VMs 1008, and that part of hardware 1004 that executes that VM, be it hardware dedicated to that VM and/or hardware shared by that VM with others of the VMs, forms separate virtual network elements. Still in the context of NFV, a virtual network function is responsible for handling specific network functions that run in one or more VMs 1008 on top of the hardware 1004 and corresponds to the application 1002.

Hardware 1004 may be implemented in a standalone network node with generic or specific components. Hardware 1004 may implement some functions via virtualization. Alternatively, hardware 1004 may be part of a larger cluster of hardware (e.g. such as in a data center or CPE) where many hardware nodes work together and are managed via management and orchestration 1010, which, among others, oversees lifecycle management of applications 1002. In some embodiments, hardware 1004 is coupled to one or more radio units that each include one or more transmitters and one or more receivers that may be coupled to one or more antennas. Radio units may communicate directly with other hardware nodes via one or more appropriate network interfaces and may be used in combination with the virtual components to provide a virtual node with radio capabilities, such as a radio access node or a base station. In some embodiments, some signaling can be provided with the use of a control system 1012 which may alternatively be used for communication between hardware nodes and radio units.

FIGURE 15 illustrates an example method 1100 by a transmitting radio node for RLC transmissions, according to certain embodiments. In the illustrated embodiment, the method includes at least one of a determining step at 1102 and a taking step at 1104. For example, at step 1102, the transmitting radio node may determine at least one RLC PDU not to be retransmitted by the transmitting radio node. At step 1104, for example, based on the information, the transmitting radio node may take at least one action to prevent a retransmission of the at least one RLC PDU while the transmitting radio node is in RLC AM.

FIGURE 16 illustrates an example method 1200 by a receiving radio node for RLC transmissions, according to certain embodiments. In the illustrated embodiment, the method includes at least one of a determining step at 1202 and a taking step at 1204 For example, at step 1202, the receiving radio node may determine at least one RLC PDU not to be retransmitted by a transmitting radio node to the receiving radio node. At step 1204, for example, the receiving radio node may take at least one action associated with the at least on RLC PDU not to be retransmitted to the receiving radio node.

FIGURE 17 illustrates another example method 1300 by a receiving radio node for Radio Link Control (RLC) transmissions, according to certain embodiments. In the illustrated embodiment, the method includes at least one of a determining step at 1302 and a taking step at 1304. For example, at step 1302, the receiving radio node may determine at least one RLC PDU for which retransmission by a transmitting radio node is not needed. At step 1304, for example, the receiving radio node may take at least one action to prevent the retransmission of the at least one RLC PDU by the transmitting radio node.

FIGURE 18 illustrates another example method 1400 by a transmitting radio node for Radio Link Control (RLC) transmissions, according to certain embodiments. In the illustrated embodiment, the method includes at least one of a determining step at 1402 and a taking step at 1404. For example, at step 1402, the transmitting radio node may determine at least one RLC PDU not to be retransmitted to a receiving radio node. At step 1404, for example, the transmitting radio node may take at least one action to prevent a retransmission of the at least one RLC PDU to a receiving radio node.

FIGURE 19 illustrates a method 1500 performed by a receiving radio node 710, 712 for Radio Link Control, RLC, transmissions, according to certain embodiments. In the illustrated embodiment, the method begins at step 1502 when the receiving radio node 710, 712 receives, from a transmitting node 710, 712, information indicating that at least one RLC PDU is not to be retransmitted by the transmitting radio node. At step 1504, the receiving radio node 710, 712 takes at least one action associated with the at least one RLC PDU not to be retransmitted to the receiving radio node 710, 712, and the at least one action includes updating at least one parameter associated with an RLC receiving window.

In a particular embodiment, at least one of the transmitting radio node 710, 712 and the receiving radio node 710, 712 are in RLC AM.

In a particular embodiment, taking the at least one action includes transmitting an acknowledgment message to the transmitting node 710, 712.

In a particular embodiment, updating the at least one parameter associated with the RLC receiving window includes advancing a lower end of the RLC receiving window forward.

In a particular embodiment, taking the at least one action comprises at least one of: discarding the at least one RLC PDU not to be retransmitted; discarding all RLC PDUs that are associated with at least one RLC SDU associated with the at least one RLC PDU not to be retransmitted; considering the at least one RLC PDU as being positively received by the receiving radio node; and transmitting at least one feedback message based on the information.

In a particular embodiment, the method includes determining at least one additional packet that has a dependency or association with the at least one RLC PDU and taking the at least one action with regard to the at least one additional packet.

In a particular embodiment, the method includes receiving, from a transmitting radio node 710, 712, at least one control or data PDU that indicates and/or is used for determining that the at least one RLC PDU is not to be retransmitted to the receiving radio node 710, 712 and/or that at least one RLC SN associated with the RLC PDU is to be discarded.

In a further particular embodiment, the at least one control or data PDU indicates at least one of: at least one SN associated with the at least one RLC PDU, at least one lowest SN associated with the at least one RLC PDU, at least one E-field associated with the at least one RLC PDU, a range of SNs associated with the at least one RLC PDU, a range of SNs associated with at least one other RLC PDU, a lower end of the RLC receiving window used for determining RLC PDUs, and at least one bit indicating that at least one SN is included for determining the at least one RLC PDU.

In a further particular embodiment, the at least one control or data PDU is included in a status PDU.

In a further particular embodiment, the at least one control or data PDU is at least one control PDU and includes a CPT value, and the method includes determining, based on the CPT value, that the at least one RLC PDU is not to be retransmitted to the receiving radio node 710, 712 and/or that the at least one RLC SN associated with the RLC PDU is to be discarded.

In a further particular embodiment, the at least one control or data PDU is a data PDU and comprises at least one bit that indicates or is for determining the at least one RLC PDU that is not to be retransmitted to the receiving radio node 710, 712.

In a further particular embodiment, the data PDU comprises an Acknowledge Mode Data PDU.

In a particular embodiment, the method includes receiving, from a network node 710, information for determining that the at least one RLC PDU is not to be retransmitted and/or for determining to take the at least one action.

In a further particular embodiment, the information includes a maximum retransmission threshold and wherein at least one of: the at least one RLC PDU is determined not to be retransmitted when the maximum retransmission threshold is reached and/or exceeded, and the at least one action is taken when the maximum retransmission threshold is reached and/or exceeded.

In a further particular embodiment, the maximum retransmission threshold is less than a configured maximum RLC AM retransmission used for RLC failure to reestablish RRC connection.

In a further particular embodiment, the information includes a maximum delay threshold. Additionally, the at least one RLC PDU is determined not to be retransmitted when the maximum delay threshold is reached and/or exceeded, and/or the at least one action is taken when the maximum delay threshold is reached and/or exceeded.

In a further particular embodiment, the maximum retransmission threshold and/or the maximum delay threshold is associated with a PDU Set Importance level indicating a level of importance of a set of packets of which the at least one RLC PDU is associated.

FIGURE 20 illustrates a method 1600 performed by a transmitting radio node 710, 712 for RLC transmissions, according to certain embodiments. In the illustrated embodiment, the method begins at step 1602 when the transmitting radio node 710, 712 determines that at least one RLC PDU is not to be retransmitted by the transmitting radio node 710, 712. At step 1604, the transmitting radio node 710, 712 takes at least one action to prevent a retransmission of the at least one RLC PDU to a receiving radio node 710, 712. The at least one action includes transmitting, to the receiving radio node 710, 712, a message indicating that the at least one RLC PDU is not to be retransmitted and updating at least one parameter associated with an RLC transmitting window.

In a particular embodiment, at least one of the transmitting radio node and the receiving radio node are in RLC AM.

In a particular embodiment, the transmitting radio node 710, 712 receives an acknowledgement message from the receiving node.

In a particular embodiment, updating the at least one parameter associated with the RLC transmitting window includes advancing a lower end of the RLC transmitting window forward.

In a particular embodiment, taking the at least one action to prevent the retransmission of the at least one RLC PDU comprises at least one of: considering the at least one RLC PDU as being positively received by the receiving radio node; discarding the at least one RLC PDU; stopping at least one ongoing transmission of the at least one RLC PDU; and determining not to send an indication to an upper layer of successful delivery of the at least one RLC PDU.

In a particular embodiment, the transmitting radio node 710, 712 determines at least one additional packet has a dependency or association with the at least one RLC PDU and takes the at least one action with regard to the at least one additional packet.

In a particular embodiment, the message transmitted to the receiving radio node 710, 712 that indicates that the at least one RLC PDU is not to be retransmitted is control or data PDU.

In a further particular embodiment, the at least one control or data PDU indicates at least one of: at least one SN associated with the at least one RLC PDU, at least one lowest SN associated with the at least one RLC PDU, at least one E-field associated with the at least one RLC PDU, a range of SNs associated with the at least one RLC PDU, a range of SNs associated with at least one other RLC PDU, a SN associated with a low end of a RLC transmitting window used for determining the at least one RLC PDU, and at least one bit indicating that at least one SN is included for determining the at least one RLC PDU.

In a further particular embodiment, the at least one control or data PDU is at least one control PDU and comprises a CPT value indicating that the at least one RLC PDU is not to be retransmitted and/or that the at least one RLC SDU associated with the RLC PDU is to be discarded.

In a further particular embodiment, the at least one control or data PDU is a data PDU and includes at least one bit that indicates or is for determining the at least one RLC PDU that is not to be retransmitted and/or that at least one RLC SDU associated with the RLC PDU is to be discarded.

In a further particular embodiment, the transmitting radio node 710, 712 receives, from a network node, information for determining that the at least one RLC PDU is not to be retransmitted and/or for determining to take the at least one action.

In a particular embodiment, the information includes a maximum retransmission threshold and the at least one RLC PDU is determined not to be retransmitted when the maximum retransmission threshold is reached and/or exceeded and/or the at least one action is taken when the maximum retransmission threshold is reached and/or exceeded.

In a further particular embodiment, the information comprises a maximum delay threshold, and the at least one RLC PDU is determined not to be retransmitted when the maximum delay threshold is reached and/or exceeded and/or the at least one action is taken when the maximum delay threshold (is reached and/or exceeded.

Although the computing devices described herein (e.g., UEs, network nodes, hosts) may include the illustrated combination of hardware components, other embodiments may comprise computing devices with different combinations of components. It is to be understood that these computing devices may comprise any suitable combination of hardware and/or software needed to perform the tasks, features, functions and methods disclosed herein. Determining, calculating, obtaining or similar operations described herein may be performed by processing circuitry, which may process information by, for example, converting the obtained information into other information, comparing the obtained information or converted information to information stored in the network node, and/or performing one or more operations based on the obtained information or converted information, and as a result of said processing making a determination. Moreover, while components are depicted as single boxes located within a larger box, or nested within multiple boxes, in practice, computing devices may comprise multiple different physical components that make up a single illustrated component, and functionality may be partitioned between separate components. For example, a communication interface may be configured to include any of the components described herein, and/or the functionality of the components may be partitioned between the processing circuitry and the communication interface. In another example, non-computationally intensive functions of any of such components may be implemented in software or firmware and computationally intensive functions may be implemented in hardware.

In certain embodiments, some or all of the functionality described herein may be provided by processing circuitry executing instructions stored on in memory, which in certain embodiments may be a computer program product in the form of a non-transitory computer-readable storage medium. In alternative embodiments, some or all of the functionalities may be provided by the processing circuitry without executing instructions stored on a separate or discrete device-readable storage medium, such as in a hard-wired manner. In any of those particular embodiments, whether executing instructions stored on a non-transitory computer-readable storage medium or not, the processing circuitry can be configured to perform the described functionality. The benefits provided by such functionality are not limited to the processing circuitry alone or to other components of the computing device but are enjoyed by the computing device as a whole, and/or by end users and a wireless network generally.

EXAMPLE EMBODIMENTS

Group A Example Embodiments

Example Embodiment Al. A method performed by a user equipment for flexible Radio Link Control (RLC) transmissions, the method comprising: any of the user equipment steps, features, or functions described above, either alone or in combination with other steps, features, or functions described above.

Example Embodiment A2. The method of the previous embodiment, further comprising one or more additional user equipment steps, features or functions described above.

Example Embodiment A3. The method of any of the previous embodiments, further comprising: providing user data; and forwarding the user data to a host computer via the transmission to the network node.

Group B Example Embodiments

Example Embodiment BL A method performed by a network node flexible Radio Link Control (RLC) transmissions, the method comprising: any of the network node steps, features, or functions described above, either alone or in combination with other steps, features, or functions described above.

Example Embodiment B2. The method of the previous embodiment, further comprising one or more additional network node steps, features or functions described above.

Example Embodiment B3. The method of any of the previous embodiments, further comprising: obtaining user data; and forwarding the user data to a host or a user equipment.

Group C Example Embodiments

Example Embodiment Cl . A method performed by a transmitting radio node for RLC transmissions, the method comprising at least one of: determining at least one RLC PDU not to be retransmitted by the transmitting radio node; and taking at least one action to prevent a retransmission of the at least one RLC PDU to a receiving radio node.

Example Embodiment C2. The method of Example Embodiment Cl, wherein at least one of the transmitting radio node and the receiving radio node are in RLC AM.

Example Embodiment C3. The method of any one of Example Embodiments Cl to C2, wherein taking the at least one action to prevent the retransmission of the at least one RLC PDU comprises at least one of: determining not to retransmit the at least one RLC PDU based on the information; removing the at least one RLC PDU from a queueing buffer; considering the at least one RLC PDU as being positively received by at least one receiving radio node; and discarding the at least one RLC PDU; stopping at least one ongoing transmission of the at least one RLC PDU; determining not to send an indication to an upper layer of successful delivery of the at least one RLC PDU; and updating at least one parameter associated with a RLC transmitting window.

Example Embodiment C4. The method of Example Embodiment C3, wherein updating the at least one parameter associated with the RLC transmitting window comprises advancing a lower end of the RLC transmitting window forward.

Example Embodiment C5. The method of any one of Example Embodiments Cl to C4, comprising: determining at least one additional packet has a dependency or association with the at least one RLC PDU; and take the at least one action with regard to the at least one additional packet.

Example Embodiment C6. The method of any one of Example Embodiments Cl to C5, wherein taking the at least one action comprises transmitting, to the receiving radio node, at least one control PDU that indicates that the at least one RLC PDU is not to be retransmitted and/or that at least one RLC SDU associated with the RLC PDU is to be discarded.

Example Embodiment C7. The method of Example Embodiment C6, wherein the at least one control PDU comprises a Control PDU Type (CPT) value indicating that the at least one RLC PDU is not to be retransmitted and/or that the at least one RLC SDU associated with the RLC PDU is to be discarded.

Example Embodiment C8. The method of any one of Example Embodiments C6 to C7, wherein the at least one control PDU indicates at least one of: at least one SN associated with the at least one RLC PDU, at least one lowest SN associated with the at least one RLC PDU, at least one E-field associated with the at least one RLC PDU, a range of SNs associated with the at least one RLC PDU, a SN associated with a low end of a RLC transmitting window used for determining the at least one RLC PDU, and at least one bit indicating that at least one SN is included for determining the at least one RLC PDU.

Example Embodiment C9. The method of any one of Example Embodiments C6 to C8, wherein the at least one control PDU is included in a status PDU.

Example Embodiment CIO. The method of any one of Example Embodiments Cl to C5, wherein taking the at least one action comprises transmitting, to the receiving radio node, at least one data PDU that indicates and/or is used for determining that the at least one RLC PDU is not to be retransmitted and/or that at least one RLC SDU associated with the RLC PDU is to be discarded.

Example Embodiment Cl l. The method of Example Embodiment CIO, wherein the data PDU comprises at least one bit indicating or for determining the at least one RLC PDU that is not to be retransmitted and/or that at least one RLC SDU associated with the RLC PDU is to be discarded.

Example Embodiment Cl 2. The method of any one of Example Embodiments CIO to Cl 1, wherein the data PDU comprises an Acknowledge Mode Data (AMD) PDU.

Example Embodiment C 13. The method of any one of Example Embodiments CIO to Cl 2, wherein the at least one data PDU indicates at least one of: at least one SN associated with the at least one RLC PDU, at least one lowest SN associated with the at least one RLC PDU, a range of SNs associated with the at least one RLC PDU, a range of SNs associated with at least one other RLC PDU, a SN associated with a low end of a RLC window used for determining the at least one RLC PDU, and at least one bit indicating that at least one SN is included for determining the retransmission of the at least one RLC PDU.

Example Embodiment Cl 4. The method of any one of Example Embodiments Cl to C13, comprising obtaining information to be used for determining the at least one RLC PDU not to be retransmitted and/or for determining to take the at least one action.

Example Embodiment Cl 5. The method of Example Embodiment Cl 4, wherein the information is received from a network node via RRC signaling.

Example Embodiment Cl 6. The method of any one of Example Embodiments C14 to C15, wherein the information comprises a maximum retransmission threshold (e.g., R_thresh) and wherein at least one of: the at least one RLC PDU is determined not to be retransmitted when the maximum retransmission threshold (e g., R_thresh)is reached and/or exceeded, and the at least one action is taken when the maximum retransmission threshold (e.g., R_thresh) is reached and/or exceeded.

Example Embodiment C17. The method of Example Embodiment C16, wherein the maximum retransmission threshold (e.g., R_thresh) is less than a configured maximum RLC AM retransmission used for RLC failure to reestablish Radio Resource Control (RRC) connection.

Example Embodiment Cl 8. The method of any one of Example Embodiments C14 to C17, wherein the information comprises a maximum delay threshold (e.g., L_thr), and wherein at least one of: the at least one RLC PDU is determined not to be retransmitted when the maximum delay threshold (e.g., L_thr)is reached and/or exceeded, and the at least one action is taken when the maximum delay threshold (e.g., L_thr) is reached and/or exceeded.

Example Embodiment Cl 9. The method of any one of Example Embodiments C15 to C16, wherein the maximum retransmission threshold (e.g., R_thresh) and/or the maximum delay threshold (e.g., L_thr) is associated with a PDU Set Importance (PSI) level indicating a level of importance of a set of packets of which the at least one RLC PDU is associated.

Example Embodiment C20. The method of Example Embodiments Cl to Cl 9, wherein the transmitting radio node comprises a UE.

Example Embodiment C21. The method of Example Embodiment C20, further comprising: providing user data; and forwarding the user data to a host via the transmission to the network node.

Example Embodiment C22. The method of Example Embodiments Cl to Cl 9, wherein the transmitting radio node comprises a network node.

Example Embodiment C23. The method of Example Embodiments C22, further comprising: obtaining user data; and forwarding the user data to a host or a user equipment.

Example Embodiment C24. A transmitting radio node comprising processing circuitry configured to perform any of the methods of Example Embodiments Cl to C23.

Example Embodiment C25 A transmitting radio node configured to and/or adapted to perform any of the methods of Example Embodiments Cl to C23.

Example Embodiment C26. A transmitting radio node comprising processing circuitry configured to perform any of the methods of Example Embodiments Cl to C23

Example Embodiment C27. A computer program comprising instructions which when executed on a computer perform any of the methods of Example Embodiments Cl to C23.

Example Embodiment C28. A computer program product comprising computer program, the computer program comprising instructions which when executed on a computer perform any of the methods of Example Embodiments Cl to C23.

Example Embodiment C29. A non-transitory computer readable medium storing instructions which when executed by a computer perform any of the methods of Example Embodiments Cl to C3.

Group D Example Embodiments

Example Embodiment DI. A method performed by a receiving radio node for RLC transmissions, the method comprising at least one of determining at least one RLC PDU not to be retransmitted by a transmitting radio node to the receiving radio node; and taking at least one action associated with the at least on RLC PDU not to be retransmitted to the receiving radio node.

Example Embodiment D2. The method of Example Embodiment Cl, wherein at least one of the transmitting radio node and the receiving radio node are in RLC AM.

Example Embodiment D3. The method of any one of Example Embodiments DI to D2, wherein taking the at least one action comprises at least one of: discarding the at least one RLC PDU not to be retransmitted; discarding all RLC PDUs that are associated with the at least one RLC SDU associated with the at least one RLC PDU not to be retransmitted; considering the at least one RLC PDU as being positively received by the receiving radio node; transmitting at least one feedback message based on the information; and updating at least one parameter associated with a RLC receiving window.

Example Embodiment D4. The method of Example Embodiment D3, wherein updating the at least one parameter associated with the RLC receiving window comprises advancing a lower end of a RLC receiving window forward.

Example Embodiment D5. The method of any one of Example Embodiments DI to D4, comprising: determining at least one additional packet that has a dependency or association with the at least one RLC PDU; and taking the at least one action with regard to the at least one additional packet.

Example Embodiment D6. The method of any one of Example Embodiments DI to D5, comprising receiving, from a transmitting radio node, at least one control PDU that indicates and/or is used for determining: that the at least one RLC PDU is not to be retransmitted to the receiving radio node, and/or that at least one RLC SN associated with the RLC PDU is to be discarded.

Example Embodiment D7. The method of Example Embodiment D6, wherein the at least one control PDU comprises a Control PDU Type (CPT) value and the method comprises: determining, based on the CPT value, that the at least one RLC PDU is not to be retransmitted to the receiving radio node and/or that the at least one RLC SN associated with the RLC PDU is to be discarded.

Example Embodiment D8. The method of any one of Example Embodiments D6 to D7, wherein the at least one control PDU indicates at least one of: at least one SN associated with the at least one RLC PDU, at least one lowest SN associated with the at least one RLC PDU, at least one E-field associated with the eat least one RLC PDU, a range of SNs associated with the at least one RLC PDU, a range of SNs associated with at least one other RLC PDU, a low end of a RLC window used for determining RLC PDUs, and at least one bit indicating that at least one SN is included for determining the at least one RLC PDU.

Example Embodiment D9. The method of any one of Example Embodiments D6 to D8, wherein the at least one control PDU is included in a status PDU.

Example Embodiment DIO. The method of any one of Example Embodiments DI to D5, comprising receiving at least one data PDU that indicates and/or is used for determining that the at least one RLC PDU is not to be retransmitted to the receiving radio node.

Example Embodiment Dll. The method of Example Embodiment DIO, wherein the data PDU comprises at least one bit indicating or for determining the at least one RLC PDU that is not to be retransmitted to the receiving radio node.

Example Embodiment D 12. The method of any one of Example Embodiments D 10 to D 11, wherein the data PDU comprises an AMD PDU.

Example Embodiment D 13. The method of any one of Example Embodiments DIO to D 12, wherein the at least one data PDU indicates at least one of: at least one SN associated with the at least one RLC PDU, at least one lowest SN associated with the at least one RLC PDU, at least one E-field associated with the eat least one RLC PDU, a range of SNs associated with the at least one RLC PDU, a range of SNs associated with at least one other RLC PDU, a low end of a RLC window used for determining the at least one RLC PDU, and at least one bit indicating that at least one SN is included for determining the at least one RLC PDU.

Example Embodiment D 14. The method of any one of Example Embodiments D 1 to D 13, comprising obtaining information for determining the at least one RLC PDU not to be retransmitted and/or for determining to take the at least one action.

Example Emboidment DI 5. The method of Example Embodiment DI 4, wherein obtaining the information comprises receiving the information from a network node via RRC signaling.

Example Embodiment D 16. The method of any one of Example Embodiments D 14 to D 15, wherein the information comprises a maximum retransmission threshold (e.g., R_thresh) and wherein at least one of: the at least one RLC PDU is determined not to be retransmitted when the maximum retransmission threshold (e g., R_thresh) is reached and/or exceeded, and the at least one action is taken when the maximum retransmission threshold (e.g., R_thresh) is reached and/or exceeded.

Example Embodiment DI 7. The method of Example Embodiment D16, wherein the maximum retransmission threshold (e.g., R_thresh) is less than a configured maximum RLC AM retransmission used for RLC failure to reestablish Radio Resource Control (RRC) connection.

Example Embodiment DI 8. The method of any one of Example Embodiments D14 to DI 7, wherein the information comprises a maximum delay threshold (e g., L_thr), and wherein at least one of: the at least one RLC PDU is determined not to be retransmitted when the maximum delay threshold (e.g., L_thr) is reached and/or exceeded, and the at least one action is taken when the maximum delay threshold (e.g., L thr) is reached and/or exceeded.

Example Embodiment DI 9. The method of any one of Example Embodiments D16 to DI 8, wherein the maximum retransmission threshold (e.g., R_thresh) and/or the maximum delay threshold (e.g., L_thr) is associated with a PDU Set Importance (PSI) level indicating a level of importance of a set of packets of which the at least one RLC PDU is associated.

Example Embodiment D20. The method of Example Embodiments DI to D19, wherein the receiving radio node comprises a UE.

Example Embodiment D21. The method of Example Embodiment D20, further comprising: providing user data; and forwarding the user data to a host via the transmission to the network node.

Example Embodiment D22. The method of Example Embodiments DI to DI 9, wherein the transmitting radio node comprises a network node.

Example Embodiment D23. The method of Example Embodiment D22, further comprising: obtaining user data; and forwarding the user data to a host or a user equipment.

Example Embodiment D24. A receiving radio node comprising processing circuitry configured to perform any of the methods of Example Embodiments DI to D23.

Example Embodiment D25. A receiving radio node configured to and/or adapted to perform any of the methods of Example Embodiments DI to D23.

Example Embodiment D26. A receiving radio node comprising processing circuitry configured to perform any of the methods of Example Embodiments DI to D23.

Example Embodiment D27. A computer program comprising instructions which when executed on a computer perform any of the methods of Example Embodiments DI to D23.

Example Embodiment D28. A computer program product comprising computer program, the computer program comprising instructions which when executed on a computer perform any of the methods of Example Embodiments DI to D23.

Example Embodiment D29. A non-transitory computer readable medium storing instructions which when executed by a computer perform any of the methods of Example Embodiments D 1 to D23.

Group E Example Embodiments

Example Embodiment El A method performed by a receiving radio node for RLC transmissions, the method comprising at least one of: determining at least one RLC PDU for which retransmission by a transmitting radio node is not needed; and taking at least one action to prevent the retransmission of the at least one RLC PDU by the transmitting radio node.

Example Embodiment E2. The method of Example Embodiment El, wherein at least one of the receiving radio node and the transmitting radio node are in RLC AM.

Example Embodiment E3. The method of any one of Example Embodiments El to E2, wherein taking the at least one action to prevent the retransmission of the at least one RLC PDU comprises at least one of: removing the at least one RLC PDU from a buffer; considering the at least one RLC PDU as being positively received by the receiving radio node; and discarding the at least one RLC PDU; determining not to send an indication to an upper layer of successful reception of the at least one RLC PDU; and updating at least one parameter associated with a RLC receiving window.

Example Embodiment E4. The method of Example Embodiment E3, wherein updating the at least one parameter associated with the RLC receiving window comprises advancing a lower end of the RLC receiving window forward.

Example Embodiment E5. The method of any one of Example Embodiments El to E4, comprising: determining at least one additional packet that has a dependency or association with the at least one RLC PDU; and taking the at least one action with regard to the at least one additional packet.

Example Embodiment E6. The method of any one of Example Embodiments El to E5, wherein taking the at least one action comprises transmitting, to the transmitting radio node, at least one control PDU that indicates that the at least one RLC PDU is not to be retransmitted.

Example Embodiment E7. The method of Example Embodiment E6, wherein the at least one control PDU comprises a Control PDU Type (CPT) value indicating that the at least one RLC PDU is not to be retransmitted and/or that the at least one RLC SN associated with the RLC PDU is to be discarded.

Example Embodiment E8. The method of any one of Example Embodiments E6 to E7, wherein the at least one control PDU indicates at least one of: at least one SN associated with the at least one RLC PDU, at least one lowest SN associated with the at least one RLC PDU, at least one E-field associated with the at least one RLC PDU, a range of SNs associated with the at least one RLC PDU, a range of SNs associated with at least one other RLC PDU, a low end of a RLC receiving window used for determining the at least one RLC PDU, and at least one bit indicating that at least one SN is included for determining the at least one RLC PDU.

Example Embodiment E9. The method of any one of Example Embodiments E6 to E8, wherein the at least one control PDU is included in a status PDU.

Example Embodiment E10. The method of any one of Example Embodiments El to E9, comprising obtaining information for determining the at least one RLC PDU not to be retransmitted and/or for determining to take the at least one action.

Example Embodiment El l. The method of Example Embodiment E10, wherein obtaining the information comprises receiving the information from a network node via RRC signaling.

Example Embodiment E12. The method of any one of Example Embodiments E10 to El 1, wherein the information comprises a maximum retransmission threshold (e.g., R_thresh) and wherein at least one of: the at least one RLC PDU is determined not to be retransmitted when the maximum retransmission threshold (e g., R_thresh) is reached and/or exceeded, and the at least one action is taken when the maximum retransmission threshold (e.g., R_thresh) is reached and/or exceeded.

Example Embodiment E13. The method of Example Embodiment E12, wherein the maximum retransmission threshold (e.g., R_thresh) is less than a configured maximum RLC AM retransmission used for RLC failure to reestablish Radio Resource Control (RRC) connection.

Example Embodiment E14. The method of any one of Example Embodiments E10 to E13, wherein the information comprises a maximum delay threshold (e.g., L_thr), and wherein at least one of: the at least one RLC PDU is determined not to be retransmitted when the maximum delay threshold (e.g., L thr) is reached and/or exceeded, and the at least one action is taken when the maximum delay threshold (e.g., L_thr) is reached and/or exceeded.

Example Embodiment El 5. The method of any one of Example Embodiments E12 to E14, wherein the maximum retransmission threshold e.g., R_thresh) and/or the maximum delay threshold (e.g., L_thr) is associated with a PDU Set Importance (PSI) level indicating a level of importance of a set of packets of which the at least one RLC PDU is associated.

Example Embodiment E16. The method ofExample Embodiments El to E15, wherein the receiving radio node comprises a UE.

Example Embodiment E17. The method ofExample Embodiment E16 further comprising: providing user data; and forwarding the user data to a host via the transmission to the network node.

Example Embodiment El 8. The method ofExample Embodiments El to El 5, wherein the receiving radio node comprises a network node.

Example Embodiment El 9. The method ofExample Embodiment El 8, further comprising: obtaining user data; and forwarding the user data to a host or a user equipment.

Example Embodiment E20. A receiving radio node comprising processing circuitry configured to perform any of the methods ofExample Embodiments El to E19.

Example Embodiment E21. A receiving radio node configured to and/or adapted to perform any of the methods ofExample Embodiments El to E19.

Example Embodiment E22. A receiving radio node comprising processing circuitry configured to perform any of the methods ofExample Embodiments El to E19.

Example Embodiment E23. A computer program comprising instructions which when executed on a computer perform any of the methods ofExample Embodiments El to E19.

Example Embodiment E24. A computer program product comprising computer program, the computer program comprising instructions which when executed on a computer perform any of the methods ofExample Embodiments El to E19.

Example Embodiment E25. A non-transitory computer readable medium storing instructions which when executed by a computer perform any of the methods of Example Embodiments El to E19.

Group F Example Embodiments

Example Embodiment Fl. A method performed by a transmitting radio node for RLC transmissions, the method comprising at least one of: determining at least one RLC PDU not to be retransmitted to a receiving radio node; and taking at least one action to prevent a retransmission of the at least one RLC PDU to a receiving radio node.

Example Embodiment F2. The method of Example Embodiment Fl, wherein at least one of the transmitting radio node and the receiving radio node are in RLC AM.

Example Embodiment F3. The method of any one of Example Embodiments Fl to F2, wherein taking the at least one action comprises at least one of: determining not to retransmit the at least one RLC PDU based on the information; removing the at least one RLC PDU from a buffer; considering the at least one RLC PDU as being positively received by the receiving radio node; discarding the at least one RLC PDU; stopping at least one ongoing transmission of the at least one RLC PDU; determining not to send an indication to an upper layer of successful transmission of the at least one RLC PDU; and updating at least one parameter associated with a RLC transmitting window.

Example Embodiment F4. The method of Example Embodiment F3, wherein updating the at least one parameter associated with the RLC transmitting window comprises advancing a lower end of a RLC transmitting window forward.

Example Embodiment F5. The method of any one of Example Embodiments Fl to F4, comprising: determining at least one additional packet that has a dependency or association with the at least one RLC PDU; and taking the at least one action with regard to the at least one additional packet.

Example Embodiment F6. The method of any one of Example Embodiments Fl to F5, comprising receiving, from the receiving radio node, at least one control PDU that indicates and/or is used for determining that the at least one RLC PDU is not to be retransmitted to the receiving radio node.

Example Embodiment F7. The method of Example Embodiment F6, wherein the at least one control PDU comprises a Control PDU Type (CPT) value indicating that the at least one RLC PDU is not to be retransmitted to the receiving radio node and/or the at least one RLC SN associated with the RLC PDU is to be discarded.

Example Embodiment F8. The method of any one of Example Embodiments F5 to F6, wherein the at least one control PDU indicates at least one of: at least one sequence number associated with the at least one RLC PDU, at least one lowest SN associated with the at least one RLC PDU, at least one E-field associated with the eat least one RLC PDU, a range of SNs associated with the at least one RLC PDU, a range of SNs associated with at least one other RLC PDU, a low end of a RLC window used for determining RLC PDUs, and at least one bit indicating that at least one SN is included for determining the at least one RLC PDU.

Example Embodiment F9. The method of any one of Example Embodiments F6 to F8, wherein the at least one control PDU is included in a status PDU.

Example Embodiment F10. The method of any one of Example Embodiments Fl to F9, comprising obtaining information for determining the at least one RLC PDU not to be retransmitted and/or for determining to take the at least one action.

Example Embodiment F 11. The method of Example Embodiment F10, wherein obtaining the information comprises receiving the information from a network node via RRC signaling.

Example Embodiment Fl 2. The method of any one of Example Embodiments F10 to Fl 1, wherein the information comprises a maximum retransmission threshold (e.g., R_thresh)and wherein at least one of: the at least one RLC PDU is determined not to be retransmitted when the maximum retransmission threshold (e g., R_thresh) is reached and/or exceeded, and the at least one action is taken when the maximum retransmission threshold (e.g., R_thresh) is reached and/or exceeded.

Example Embodiment F13. The method of Example Embodiment F12, wherein the maximum retransmission threshold (e.g., R_thresh) is less than a configured maximum RLC AM retransmission used for RLC failure to reestablish Radio Resource Control (RRC) connection.

Example Embodiment Fl 4. The method of any one of Example Embodiments F10 to F13, wherein the information comprises a maximum delay threshold (e.g., L_thr), and wherein at least one of: the at least one RLC PDU is determined not to be retransmitted when the maximum delay threshold (e.g., L thr) is reached and/or exceeded, and the at least one action is taken when the maximum delay threshold (e.g., L_thr) is reached and/or exceeded.

Example Embodiment F 15. The method of any one of Example Embodiments F12 to F14, wherein the maximum retransmission threshold (e.g., R_thresh) and/or the maximum delay threshold (e.g., L_thr) is associated with a PDU Set Importance (PSI) level indicating a level of importance of a set of packets of which the at least one RLC PDU is associated.

Example Embodiment Fl 6. The method of Example Embodiments Fl to F15, wherein the transmitting radio node comprises a UE.

Example Embodiment F 17. The method ofExample EmbodimentF16, further comprising: providing user data; and forwarding the user data to a host via the transmission to the network node.

Example Embodiment Fl 8. The method of Example Embodiments Fl to F15, wherein the transmitting radio node comprises a network node.

Example Embodiment F 19. The method of Example Embodiment F 18, further comprising: obtaining user data; and forwarding the user data to a host or a user equipment.

Example Embodiment F20. A receiving radio node comprising processing circuitry configured to perform any of the methods of Example Embodiments Fl to Fl 9.

Example Embodiment F21. A receiving radio node configured to and/or adapted to perform any of the methods of Example Embodiments Fl to F19.

Example Embodiment F22. A receiving radio node comprising processing circuitry configured to perform any of the methods of Example Embodiments Fl to Fl 9.

Example Embodiment F23. A computer program comprising instructions which when executed on a computer perform any of the methods of Example Embodiments Fl to F19.

Example Embodiment F24. A computer program product comprising computer program, the computer program comprising instructions which when executed on a computer perform any of the methods of Example Embodiments Fl to F19.

Example Embodiment F25. A non-transitory computer readable medium storing instructions which when executed by a computer perform any of the methods of Example Embodiments Fl to Fl 9.

Group G Example Embodiments

Example Embodiment GE A user equipment for RLC transmissions, the UE comprising: processing circuitry configured to perform any of the steps of any of the Group A, C, D, E, and F Example Embodiments, and power supply circuitry configured to supply power to the processing circuitry.

Example Embodiment G2. A network node for RLC transmissions, the network node comprising: processing circuitry configured to perform any of the steps of any of the Group B, C, D, E, and F Example Embodiments; power supply circuitry configured to supply power to the processing circuitry.

Example Embodiment G3. A user equipment (UE) for Radio Link Control (RLC) transmissions, the UE comprising: an antenna configured to send and receive wireless signals; radio front-end circuitry connected to the antenna and to processing circuitry, and configured to condition signals communicated between the antenna and the processing circuitry; the processing circuitry being configured to perform any of the steps of any of the Group A, C, D, E, and F Example Embodiments; an input interface connected to the processing circuitry and configured to allow input of information into the UE to be processed by the processing circuitry; an output interface connected to the processing circuitry and configured to output information from the UE that has been processed by the processing circuitry; and a battery connected to the processing circuitry and configured to supply power to the UE.

Example Embodiment G4. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to provide user data; and a network interface configured to initiate transmission of the user data to a cellular network for transmission to a user equipment (UE), wherein the UE comprises a communication interface and processing circuitry, the communication interface and processing circuitry of the UE being configured to perform any of the steps of any of the Group A, C, D, E, and F Example Embodiments to receive the user data from the host.

Example Embodiment G5. The host of the previous Example Embodiment, wherein the cellular network further includes a network node configured to communicate with the UE to transmit the user data to the UE from the host.

Example Embodiment G6. The host of the previous 2 Example Embodiments, wherein: the processing circuitry of the host is configured to execute a host application, thereby providing the user data; and the host application is configured to interact with a client application executing on the UE, the client application being associated with the host application.

Example Embodiment G7. A method implemented by a host operating in a communication system that further includes a network node and a user equipment (UE), the method comprising: providing user data for the UE; and initiating a transmission carrying the user data to the UE via a cellular network comprising the network node, wherein the UE performs any of the operations of any of the Group A embodiments to receive the user data from the host.

Example Embodiment G8. The method of the previous Example Embodiment, further comprising: at the host, executing a host application associated with a client application executing on the UE to receive the user data from the UE.

Example Embodiment G9. The method of the previous Example Embodiment, further comprising: at the host, transmitting input data to the client application executing on the UE, the input data being provided by executing the host application, wherein the user data is provided by the client application in response to the input data from the host application.

Example Embodiment GIO. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to provide user data; and a network interface configured to initiate transmission of the user data to a cellular network for transmission to a user equipment (UE), wherein the UE comprises a communication interface and processing circuitry, the communication interface and processing circuitry of the UE being configured to perform any of the steps of any of the Group A, C, D, E, and F Example Embodiments to transmit the user data to the host.

Example Embodiment G11. The host of the previous Example Embodiment, wherein the cellular network further includes a network node configured to communicate with the UE to transmit the user data from the UE to the host.

Example Embodiment G12. The host of the previous 2 Example Embodiments, wherein: the processing circuitry of the host is configured to execute a host application, thereby providing the user data; and the host application is configured to interact with a client application executing on the UE, the client application being associated with the host application.

Example Embodiment G13. A method implemented by a host configured to operate in a communication system that further includes a network node and a user equipment (UE), the method comprising: at the host, receiving user data transmitted to the host via the network node by the UE, wherein the UE performs any of the steps of any of the Group A, C, D, E, and F Example Embodiments to transmit the user data to the host.

Example Embodiment G14. The method of the previous Example Embodiment, further comprising: at the host, executing a host application associated with a client application executing on the UE to receive the user data from the UE.

Example Embodiment G15. The method of the previous Example Embodiment, further comprising: at the host, transmitting input data to the client application executing on the UE, the input data being provided by executing the host application, wherein the user data is provided by the client application in response to the input data from the host application.

Example Embodiment G16. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to provide user data; and a network interface configured to initiate transmission of the user data to a network node in a cellular network for transmission to a user equipment (UE), the network node having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B, C, D, E, and F Example Embodiments to transmit the user data from the host to the UE.

Example Embodiment G17. The host of the previous Example Embodiment, wherein: the processing circuitry of the host is configured to execute a host application that provides the user data; and the UE comprises processing circuitry configured to execute a client application associated with the host application to receive the transmission of user data from the host.

Example Embodiment G18. A method implemented in a host configured to operate in a communication system that further includes a network node and a user equipment (UE), the method comprising: providing user data for the UE; and initiating a transmission carrying the user data to the UE via a cellular network comprising the network node, wherein the network node performs any of the operations of any of the Group B, C, D, E, and F Example Embodiments to transmit the user data from the host to the UE.

Example Embodiment G19 The method of the previous Example Embodiment, further comprising, at the network node, transmitting the user data provided by the host for the UE.

Example Embodiment G20. The method of any of the previous 2 Example Embodiments, wherein the user data is provided at the host by executing a host application that interacts with a client application executing on the UE, the client application being associated with the host application.

Example Embodiment G21. A communication system configured to provide an over-the- top service, the communication system comprising: a host comprising: processing circuitry configured to provide user data for a user equipment GTE), the user data being associated with the over-the-top service; and a network interface configured to initiate transmission of the user data toward a cellular network node for transmission to the UE, the network node having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B, C, D, E, and F Example Embodiments to transmit the user data from the host to the UE.

Example Embodiment G22. The communication system of the previous Example Embodiment, further comprising: the network node; and/or the user equipment.

Example Embodiment G23. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to initiate receipt of user data; and a network interface configured to receive the user data from a network node in a cellular network, the network node having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B, C, D, E, and F Example Embodiments to receive the user data from a user equipment (UE) for the host.

Example Embodiment G24. The host of the previous 2 Example Embodiments, wherein: the processing circuitry of the host is configured to execute a host application, thereby providing the user data; and the host application is configured to interact with a client application executing on the UE, the client application being associated with the host application.

Example Embodiment G25. The host of the any of the previous 2 Example Embodiments, wherein the initiating receipt of the user data comprises requesting the user data.

Example Embodiment G26. A method implemented by a host configured to operate in a communication system that further includes a network node and a user equipment (UE), the method comprising: at the host, initiating receipt of user data from the UE, the user data originating from a transmission which the network node has received from the UE, wherein the network node performs any of the steps of any of the Group B, C, D, E, and F Example Embodiments to receive the user data from the UE for the host.

Example Embodiment G27 The method of the previous Example Embodiment, further comprising at the network node, transmitting the received user data to the host.

Claims

1. A method (1500) performed by a receiving radio node (710, 712) for Radio Link Control, RLC, transmissions, the method comprising: receiving (1502), from a transmitting node (710, 712), information indicating that at least one RLC Protocol Data Unit, PDU, is not to be retransmitted by the transmitting radio node; and taking at least one action (1504) associated with the at least one RLC PDU not to be retransmitted to the receiving radio node, wherein taking the at least one action comprises: updating at least one parameter associated with an RLC receiving window.

2. The method of Claim 1, wherein at least one of the transmitting radio node and the receiving radio node are in Radio Link Control Acknowledgement Mode, RLC AM.

3. The method of any one of Claims 1 to 2, wherein taking the at least one action comprises transmitting an acknowledgment message to the transmitting node.

4. The method of any one of Claims 1 to 3, wherein updating the at least one parameter associated with the RLC receiving window comprises advancing a lower end of the RLC receiving window forward.

5. The method of any one of Claims 1 to 4, wherein taking the at least one action comprises at least one of: discarding the at least one RLC PDU not to be retransmitted; discarding all RLC PDUs that are associated with at least one RLC SDU associated with the at least one RLC PDU not to be retransmitted; considering the at least one RLC PDU as being positively received by the receiving radio node; and transmitting at least one feedback message based on the information.

6. The method of any one of Claims 1 to 5, comprising: determining at least one additional packet that has a dependency or association with the at least one RLC PDU; and taking the at least one action with regard to the at least one additional packet.

7. The method of any one of Claims 1 to 6, comprising receiving, from a transmitting radio node, at least one control or data PDU that indicates and/or is used for determining: that the at least one RLC PDU is not to be retransmitted to the receiving radio node, and/or that at least one RLC Sequence Number, SN, associated with the RLC PDU is to be discarded.

8. The method of Claim 7, wherein the at least one control or data PDU indicates at least one of: at least one SN associated with the at least one RLC PDU, at least one lowest SN associated with the at least one RLC PDU, at least one E-field associated with the at least one RLC PDU, a range of SNs associated with the at least one RLC PDU, a range of SNs associated with at least one other RLC PDU, a lower end of the RLC receiving window used for determining RLC PDUs, and at least one bit indicating that at least one SN is included for determining the at least one RLC PDU.

9. The method of any one of Claims 7 to 8, wherein the at least one control or data PDU is included in a status PDU.

10. The method of any one of Claims 7 to 9, wherein the at least one control or data PDU is at least one control PDU and comprises a Control PDU Type, CPT, value, and wherein the method comprises: determining, based on the CPT value, that the at least one RLC PDU is not to be retransmitted to the receiving radio node and/or that the at least one RLC SN associated with the RLC PDU is to be discarded.

11. The method of any one of Claims 7 to 9, wherein the at least one control or data PDU is a data PDU and comprises at least one bit that indicates or is for determining the at least one RLC PDU that is not to be retransmitted to the receiving radio node.

12. The method of Claim 11, wherein the data PDU comprises an Acknowledge Mode Data PDU.

13. The method of any one of Claims 1 to 12, comprising receiving, from a network node, information for determining that the at least one RLC PDU is not to be retransmitted and/or for determining to take the at least one action.

14. The method of Claim 13, wherein the information comprises a maximum retransmission threshold and wherein at least one of: the at least one RLC PDU is determined not to be retransmitted when the maximum retransmission threshold is reached and/or exceeded, and the at least one action is taken when the maximum retransmission threshold is reached and/or exceeded.

15. The method of Claim 14, wherein the maximum retransmission threshold is less than a configured maximum RLC AM retransmission used for RLC failure to reestablish Radio Resource Control connection.

16. The method of any one of Claims 13 to 15, wherein the information comprises a maximum delay threshold, and wherein at least one of: the at least one RLC PDU is determined not to be retransmitted when the maximum delay threshold is reached and/or exceeded, and the at least one action is taken when the maximum delay threshold is reached and/or exceeded.

17. The method of any one of Claims 14 to 16, wherein the maximum retransmission threshold and/or the maximum delay threshold is associated with a PDU Set Importance level indicating a level of importance of a set of packets of which the at least one RLC PDU is associated.

18. A method (1600) performed by a transmitting radio node (710, 712) for Radio Link Control, RLC, transmissions, the method comprising at least one of: determining (1602) that at least one RLC Protocol Data Unit, PDU, is not to be retransmitted by the transmitting radio node; and taking at least one action (1604) to prevent a retransmission of the at least one RLC PDU to a receiving radio node (710, 712), wherein taking the at least one action comprises: transmitting, to the receiving radio node, a message indicating that the at least one RLC PDU is not to be retransmitted; and updating at least one parameter associated with an RLC transmitting window.

19. The method of Claim 18, wherein at least one of the transmitting radio node and the receiving radio node are in Radio Link Control Acknowledgement Mode, RLC AM.

20. The method of any one of Claims 18 to 19, comprising receiving an acknowledgement message from the receiving node.

21. The method of any one of Claims 18 to 20, wherein updating the at least one parameter associated with the RLC transmitting window comprises advancing a lower end of the RLC transmitting window forward.

22. The method of any one of Claims 18 to 21 , wherein taking the at least one action to prevent the retransmission of the at least one RLC PDU comprises at least one of: considering the at least one RLC PDU as being positively received by the receiving radio node; discarding the at least one RLC PDU; stopping at least one ongoing transmission of the at least one RLC PDU; and determining not to send an indication to an upper layer of successful delivery of the at least one RLC PDU.

23. The method of any one of Claims 18 to 22, comprising: determining at least one additional packet has a dependency or association with the at least one RLC PDU; and taking the at least one action with regard to the at least one additional packet.

24. The method of any one of Claims 18 to 23, wherein the message transmitted to the receiving node that indicates that the at least one RLC PDU is not to be retransmitted is control or data PDU.

25. The method of Claim 24, wherein the at least one control or data PDU indicates at least one of: at least one sequence number, SN, associated with the at least one RLC PDU, at least one lowest SN associated with the at least one RLC PDU, at least one E-field associated with the at least one RLC PDU, a range of SNs associated with the at least one RLC PDU, a range of SNs associated with at least one other RLC PDU, a SN associated with a low end of a RLC transmitting window used for determining the at least one RLC PDU, and at least one bit indicating that at least one SN is included for determining the at least one RLC PDU.

26. The method of any one of Claims 24 to 25, wherein the at least one control or data PDU is included in a status PDU.

27. The method of any one of Claims 24 to 26, wherein the at least one control or data PDU is at least one control PDU and comprises a Control PDU Type, CPT, value indicating that the at least one RLC PDU is not to be retransmitted and/or that the at least one RLC SDU associated with the RLC PDU is to be discarded.

28. The method of anyone of Claims 24 to 26, wherein the at least one control or data PDU is a data PDU and comprises at least one bit that indicates or is for determining the at least one RLC PDU that is not to be retransmitted and/or that at least one RLC SDU associated with the RLC PDU is to be discarded.

29. The method of Claim 28, wherein the data PDU comprises an Acknowledge Mode Data

PDU.

30. The method of any one of Claims 18 to 29, comprising receiving, from a network node, information for determining that the at least one RLC PDU is not to be retransmitted and/or for determining to take the at least one action.

31. The method of Claim 30, wherein the information comprises a maximum retransmission threshold and wherein at least one of: the at least one RLC PDU is determined not to be retransmitted when the maximum retransmission threshold is reached and/or exceeded, and the at least one action is taken when the maximum retransmission threshold is reached and/or exceeded.

32. The method of Claim 31, wherein the maximum retransmission threshold is less than a configured maximum RLC AM retransmission used for RLC failure to reestablish Radio Resource Control connection.

33. The method of any one of Claims 30 to 32, wherein the information comprises a maximum delay threshold, and wherein at least one of: the at least one RLC PDU is determined not to be retransmitted when the maximum delay threshold is reached and/or exceeded, and the at least one action is taken when the maximum delay threshold (is reached and/or exceeded.

34. The method of any one of Claims 31 to 33, wherein the maximum retransmission threshold and/or the maximum delay threshold is associated with a PDU Set Importance level indicating a level of importance of a set of packets of which the at least one RLC PDU is associated.

35. A receiving radio node (710, 712) for Radio Link Control, RLC, transmissions, the receiving radio node configured to: receive, from a transmitting node (710, 712), information indicating that at least one RLC Protocol Data Unit, PDU, is not to be retransmitted by the transmitting radio node; and take at least one action associated with the at least on RLC PDU not to be retransmitted to the receiving radio node, wherein taking the at least one action comprises: updating at least one parameter associated with a RLC transmitting window.

36. The receiving radio node of Claim 35, configured to perform any of the methods of Claims

2 to 17.

37. A transmitting radio node (710, 712) for Radio Link Control, RLC, transmissions, the transmitting radio node configured to: determine at least one RLC Protocol Data Unit, PDU, not to be retransmitted by the transmitting radio node; and take at least one action to prevent a retransmission of the at least one RLC PDU to a receiving radio node (710, 712), wherein taking the at least one action comprises: transmitting, to a receiving radio node, a message indicating that the at least one

RLC PDU is not to be retransmitted; and updating at least one parameter associated with an RLC transmitting window.

38. The transmitting radio node of Claim 37, configured to perform any of the methods of Claims 19 to 34.