WO2023068988A1

WO2023068988A1 - Bearer handling for scg deactivation

Info

Publication number: WO2023068988A1
Application number: PCT/SE2022/050937
Authority: WO
Inventors: Zhenhua Zou; Stefan Wager; Martin Skarve
Original assignee: Telefonaktiebolaget Lm Ericsson (Publ)
Priority date: 2021-10-21
Filing date: 2022-10-17
Publication date: 2023-04-27

Abstract

Systems and/or methods are provided for user plane data handling during an SCG de-activation/re-activation procedure. In particular, upon SCG de-activation, the UE may release the RLC entities associated with the SCG. Upon SCG activation, the UE may establish the RLC entities associated with the SCG and a data split threshold associated with the deactivated SCG of infinity is applied. Related devices, systems and computer program products are disclosed.

Description

BEARER HANDLING FOR SCG DEACTIVATION

TECHNICAL FIELD

[0001] The present disclosure relates generally to communications, and more particularly to communication methods and related devices and nodes supporting wireless communications.

BACKGROUND

[0002] When Carrier Aggregation (CA) is configured in a wireless communication system, a UE uses multiple carriers to communicate with the network. Each carrier corresponds to a cell. During CA, the UE still has one radio resource control (RRC) connection with the network. Further, at RRC connection establishment/re-establishment/handover, one serving cell provides non-access stratum (NAS) mobility information for the UE and the security input to the UE. This cell is referred to as the Primary Cell (PCell). In addition, depending on UE capabilities, Secondary Cells (SCells) can be configured to form together with the PCell a set of serving cells. Therefore, when carrier aggregation is configured for the UE, the set of serving cells used by the UE always consists of one PCell and one or more SCells.

[0003] The reconfiguration, addition and removal of SCells can be performed by RRC. At intra-RAT handover (e.g., handover from an LTE network to an NR network), RRC can also add, remove, or reconfigure SCells for usage with the target PCell. When adding a new SCell, dedicated RRC signalling is used for sending all required system information of the SCell. That is, while in connected mode, UEs need not acquire broadcasted system information directly from the SCells.

[0004] In 3GPP Rel-12, the LTE feature of Dual Connectivity (DC) was introduced. DC enables the UE to be connected in two cell groups, each controlled by an LTE access node (i.e., an eNB), called the Master eNB, MeNB and the Secondary eNB, SeNB. The UE still only has one RRC connection with the network. In 3GPP, the DC solution is now also specified for NR as well as between LTE and NR. With the introduction of 5G, the term MR-DC (MultiRadio Dual Connectivity, see also 3GPP TS 37.340) was defined as a generic term for all dual connectivity options which include at least one NR access node. Using the MR-DC generalized terminology, the UE is connected in a Master Cell Group (MCG), controlled by the Master Node (MN), and in a Secondary Cell Group (SCG) controlled by a Secondary Node (SN). [0005] Further, in MR-DC, when dual connectivity is configured for the UE, within each of the two cell groups, MCG and SCG, carrier aggregation may be used as well. In this case, within the Master Cell Group, MCG, controlled by the master node (MN), the UE may use one PCell and one or more SCell(s). And within the Secondary Cell Group, SCG, controlled by the secondary node (SN), the UE may use one Primary SCell (PSCell, also known as the primary SCG cell in NR) and one or more SCell(s). This combined case is illustrated in Figure 1. In NR, the primary cell of a master or secondary cell group is sometimes also referred to as the Special Cell (SpCell). Hence, the SpCell in the MCG is the PCell and the SpCell in the SCG is the PSCell.

[0006] There are different ways to deploy 5G network with or without interworking with LTE (also referred to as E-UTRA) and evolved packet core (EPC). These different ways to deploy 5G are also known as architecture options. In principle, NR and LTE can be deployed without any interworking, denoted by NR stand-alone (SA) operation, also known as architecture option 2, that is gNB in NR can be connected to 5G core network (5GC) and eNB in LTE can be connected to EPC with no interconnection between the two, also known as architecture option 1.

[0007] On the other hand, the first supported version of NR uses dual connectivity, denoted as EN-DC (E-UTRAN-NR Dual Connectivity), also known as architecture option 3, as depicted in Figure 2. In such a deployment, dual connectivity between NR and LTE is applied, where the UE is connected with both the LTE radio interface (LTE Uu in Figure 2) to an LTE access node and the NR radio interface (NR Uu in Figure 2) to an NR access node. Further, in EN-DC, the LTE access node acts as the master node (in this case known as the Master eNB, MeNB), controlling the master cell group, MCG, and the NR access node acts as the secondary node (in this case sometimes also known as the Secondary gNB, SgNB), controlling the secondary cell group, SCG. The SgNB has a user plane connection Sl-U to the core network (EPC). The control plane connection Sl-C to the core network (EPC) is instead is provided by the MeNB. This is also called as “Non-standalone NR" or, in short, "NSA NR". Notice that in this case the functionality of an NR cell is limited and would be used for connected mode UEs as a booster and/or diversity leg, but an RRC IDLE UE cannot camp on these NR cells. In EN-DC, there is no connection to the 5G core network (5GC).

[0008] With introduction of 5GC, other options may be also valid. As noted above, option 2 supports stand-alone NR deployment where gNB is connected to 5GC. Similarly, LTE can also be connected to 5GC using option 5 (also known as eLTE, E-UTRA/5GC, or LTE/5GC and the node can be referred to as an ng-eNB). In these cases, both NR and LTE are seen as part of the NG-RAN (and both the ng-eNB and the gNB can be referred to as NG-RAN nodes). [0009] There are also other variants of dual connectivity between LTE and NR which have been standardized as part of NG-RAN connected to 5GC. Under the MR-DC umbrella, there are:

• EN-DC (also known as architecture option 3): LTE is the master node and NR is the secondary node (EPC CN employed, as depicted in Figure 2);

• NE-DC (also known as architecture option 4): NR is the master node and LTE is the secondary (5GC employed); and

• NGEN-DC (also known as architecture option 7): LTE is the master node and NR is the secondary (5GC employed).

• NR-DC (variant of architecture option 2): Dual connectivity where both the master node, MN, controlling the MCG, and the secondary node, SN, controlling the SCG, are NR (5GC employed, as depicted in Figure 3).

[0010] In NR-DC, depicted in Figure 3, the secondary node (NR SN) is a gNB, providing NR radio interface NR Uu to the UE and has a user plane connection NG-U to the 5G core network (5GC). The master node (NR MN) is also a gNB, providing NR radio interface NR Uu to the UE and has the control plane connection NG-C as well as a user plane connection NG- U to the 5G core network (5GC). Between the MN and SN the Xn interface is used.

[0011] As migration for these options may differ from different operators, it is possible to have deployments with multiple options in parallel in the same network e.g. there could be eNB base station supporting architecture options 3, 5 and 7 in the same network as NR base station supporting architecture options 2 and 4. In combination with dual connectivity solutions between LTE and NR it is also possible to support CA (Carrier Aggregation) in each cell group (i.e. MCG and SCG) and dual connectivity between nodes on same RAT (e.g. NR-NR DC). For the LTE cells, a consequence of these different deployments is the co-existence of LTE cells associated to eNBs connected to EPC, 5GC or both EPC/5GC.

[0012] As noted above, DC is standardized for both LTE and E-UTRA -NR DC (EN- DC). LTE DC and EN-DC are designed differently when it comes to which nodes control what. There are two options, namely, a centralized solution (like LTE-DC), and a decentralized solution (like EN-DC).

[0013] Figure 4 shows the schematic control plane architecture for LTE DC, EN-DC and NR-DC. The main difference here is that in EN-DC and NR-DC, the Secondary Node, SN, has a separate NR RRC entity. This means that the SN can control the UE also, sometimes using the NR radio interface NR Uu directly to the UE without the knowledge of the MN but often the SN needs to coordinate with the Master Node, MN. The UE has an LTE RRC state in EN-DC and an NR RRC state in NR-DC. Further, in LTE-DC and EN-DC, the control plane interface between MN and SN is X2-C. In LTE-DC, the RRC decisions always come from the MN (MN uses the LTE radio interface LTE Uu to the UE). Note however, the SN still decides the configuration of the SN, since it is only the SN itself that has knowledge of what kind of resources, capabilities etc. it has. Further, in LTE-DC, the UE has an LTE RRC state. Further, in NR-DC, the control plane interface between MN and SN is Xn-C.

[0014] For EN-DC and NR-DC, the major changes compared to LTE DC are:

• The introduction of split data radio bearer (DRB) from the SN (known as SN terminated split DRB);

• The introduction of split signaling radio bearer (SRB) for RRC; and

• The introduction of a direct SRB from the SN (also referred to as SCG SRB or SRB3).

[0015] Figure 5 shows, from network perspective, the user plane protocol architecture in MR-DC with EPC (EN-DC). A bearer may be categorized into a bearer type. Each bearer type is characterized by which radio resources that are involved. For an MCG bearer, only MCG radio resources and RLC+MAC layer entities for the MCG are involved. For an SCG bearer, only SCG radio resources and RLC+MAC layer entities for the SCG are involved. For a split bearer, both MCG and SCG radio resources as well as RLC+MAC layer entities for both the MCG and SCG are involved. Further, a bearer may also be categorized into MN terminated bearers and SN terminated bearers depending on which network node where they are terminated. For MN terminated bearers, the PDCP layer entity and the user plane connection to the core network is terminated in the MN. For SN terminated bearers, the PDCP layer entity and the user plane connection to the core network is terminated in the SN.

[0016] The network can configure either E-UTRA PDCP layer or NR PDCP layer for MN terminated MCG bearers while NR PDCP layer is always used for all other bearers. In this case, the network can configure either E-UTRA PDCP or NR PDCP for MN terminated MCG DRBs while NR PDCP is always used for all other DRBs.

[0017] Figure 6 shows, from the network perspective, the user plane protocol architecture in MR-DC with 5GC (NGEN-DC, NE-DC and NR-DC). In MR-DC with 5GC, NR PDCP is always used for all DRB types. In NGEN-DC, E-UTRA RLC/MAC is used in the MN while NR RLC/MAC is used in the SN. In NE-DC, NR RLC/MAC is used in the MN while E- UTRA RLC/MAC is used in the SN. In NR-DC, NR RLC/MAC is used in both MN and SN.

[0018] SCG Power Saving Mode [0019] To improve network energy efficiency and UE battery life for UEs in MR-DC, a Rel-17 work item aims to introduce a feature known as efficient SCG/SCell activation/deactivation. This can be especially important for MR-DC configurations with NR SCG, as it has been evaluated in RP-190919 that in some cases NR UE power consumption is 3 to 4 times higher than LTE.

[0020] 3 GPP has already specified the concept of deactivated SCell for LTE and NR.

As depicted in Figure 7, for NR, a given SCell can be in either "Deactivated SCell" state or "Activated SCell" state. The configured SCell(s) may be activated and deactivated by transmitting the SCell Activation/Deactivation MAC CE from the network to the UE. The SCell may also be deactivated upon expiry of a timer configured per SCell, known as the sCellDeactivationTimer. As a third option, the SCell state may be configured by RRC signalling.

[0021] 3 GPP has also specified the concepts of dormant SCell (in LTE) and dormancy like behavior of an SCell (for NR). In LTE, when an SCell is in dormant state, like in the Deactivated SCell state, the UE does not need to monitor the corresponding PDCCH or PDSCH and cannot transmit in the corresponding uplink. However, in contrast to the deactivated state, the UE is required to perform and report CQI measurements. A PUCCH SCell (SCell configured with PUCCH) cannot be in dormant state.

[0022] In NR, as also illustrated in Figure 7, dormancy like behavior for SCells is realized using the concept of dormant BWPs. When the SCell is activated, the active BWP used by the SCell can be switched between a "non-dormant" BWP and a dormant BWP. One dormant BWP, which is one of the dedicated BWPs configured by the network via RRC signaling, can be configured for an SCell. If the active BWP of the activated SCell is a dormant BWP, the UE stops monitoring PDCCH on the SCell but continues performing CSI measurements, AGC and beam management, if configured. A DCI is used to control entering/leaving the dormant BWP for one or more SCell(s) or one or more SCell group(s), and it is sent to the special cell (SpCell) of the cell group that the SCell belongs to (i.e. PCell in case the SCell belongs to the MCG and PSCell if the SCell belongs to the SCG). The SpCell (i.e. PCell of PSCell) and PUCCH SCell cannot be configured with a dormant BWP.

[0023] However, only SCells can be put to put in dormant state (in LTE) or operate in dormancy like behavior (NR). Also, only SCells can be put into the deactivated state in both LTE and NR. Thus, if the UE is configured with MR-DC, it is not possible to fully benefit from the power saving options of dormant state or dormancy like behavior as the PSCell cannot be configured with that feature. Instead, an existing solution could be releasing (for power savings) and adding (when traffic demands requires) the SCG on a need basis. However, traffic is likely to be bursty, and adding and releasing the SCG involves a significant amount of RRC signaling and inter-node messaging between the MN and the SN, which causes considerable delay.

[0024] In 3GPP Rel-16, some discussions were made regarding putting also the PSCell in dormancy, also referred to as SCG Suspension. Some preliminary agreements were made on that the UE supports network-controlled suspension of the SCG in RRC CONNECTED but that UE behavior for a suspended SCG is for future study.

[0025] The 3GPP discussions on solutions for the Rel-17 MR-DC work item objective "Support efficient activation/de-activation mechanism for one SCG and Scells" are ongoing in 3GPP. As part of this objective, the concept of a "deactivated SCG" with aim of power saving when the traffic demands are dynamically reduced is being discussed. As Figure 8 also illustrates, there are two SCG states (sometimes referred to as states for SCG activation or states for PSCell activation) being discussed, here referred to as "SCG deactivated state" and "SCG activated state". These states concern the power saving mode for the SCG and should not be confused with the RRC states.

[0026] During “SCG deactivated state”, or sometimes referred to as when "SCG is deactivated", or "deactivated PSCell" state, 3GPP RAN2 has agreed that:

• RRC configuration can select SCG activation state

• No PDCCH/PDSCH/PUSCH Tx/Rx on PSCell

• All SCells are deactivated

• SCG reconfiguration via MCG is supported

• RRM & PSCell mobility is supported

• Both RACH and RACH-less SCG activation supported

• UE keeps Time Alignment timer running

• UE continues BFD/RLM (if configured)

• SCG activation indication can indicate TCI state

[0027] There currently exist certain challenge(s). In NR, uplink (UL) data preprocessing is allowed. That is, the UE is allowed to submit the PDCP PDUs to the lower layers before receiving a request for the PDUs from the lower layers. Once the PDCP PDUs are submitted, the PDCP PDUs are not re-submitted to the lower layers unless upper layers request a PCDP entity re-establishment or a PDCP data recovery. Both procedures apply only for Acknowledge Mode (AM) DRBs.

[0028] In clause 5.2.1 Transmit operation of the PCDP specification TS 38.323, there is a note stating that "if the transmitting PDCP entity is associated with two RLC entities, the UE should minimize the amount of PDCP PDUs submitted to lower layers before receiving request from lower layers and minimize the PDCP SN gap between PDCP PDUs submitted to two associated RLC entities to minimize PDCP reordering delay in the receiving PDCP entity."

[0029] This note is not a normative UE requirement in the sense that the UE is allowed to submit PDCP PDUs to lower layers before receiving request from lower layers. Moreover, this note applies only to the case of two RLC entities, i.e., the split bearer and not applied to the MCG or SCG DRB or SRB3.

[0030] Issues may happen for those pre-processed PDCP PDUs in certain scenarios. In a first scenario, when the SCG is de-activated, upon the arrival of higher layer UL data at the UE, the UE may pre-process the PDCP SDUs and submit the PDCP PDUs to the RLC entity associated with the SCG. However, the SCG may not be re-activated for some reason.

[0031] For example, in the case of a split DRB with a secondary path on SCG, if the data volume is larger than a threshold (ul-DataSplitThreshold), then the UE may submit the PDCP PDU to the split secondary RLC entity on SCG. However, the network may decide not to activate the SCG, but rather allocate more resources on the MCG to clear UE data buffer.

[0032] In a second scenario, upon SCG de-activation, an RLC SDU may be stuck in the SCG UL at the UE due to a race condition. That is, the SCG may be de-activated while the UE has just pre-pushed some data into the UL RLC queue.

[0033] This may cause the pre-processed PDCP PDUs to become lost or to be stuck in the RLC buffer for the time the SCG is deactivated. If those PDCP PDUs are then transmitted when the SCG is again activated, it may lead to a potential wrap-around issue in the PDCP SN, since the PDCP PDUs transmitted via the MCG will have advanced the PDCP receive window while the SCG was de-activated. If the PDCP receive window was wrapped around and advanced to the point that PDCP PDUs stuck in the RLC buffer become within the PDCP receiving window, they will be processed by the PDCP receiver, but since the PDCP SN queue is wrapped around on the receiver side, it will use another COUNT value for deciphering the PDCP PDU compared to the transmitter, and deciphering will fail.

[0034] There are existing mechanisms to control user plane data handling for the associated RLC entities and PDCP entity. However, it is not clear which one to use and under which condition to solve the data stuck issue. These mechanisms include:

[0035] In the cell group configuration of a RRC reconfiguration message, it is possible for the network to set the field reestablishRLC to be true for RLC entity re-establishment or to add the RLC entity in the rlc-BearerToReleaseList for RLC entity release.

[0036] Additionally, a PDCP data recovery can be triggered by RRC layer as specified in clause 5.5 of TS 38.323, which states that "for AM DRBs, when upper layers request a PDCP data recovery for a radio bearer, the transmitting PDCP entity shall ... perform retransmission of all the PDCP Data PDUs previously submitted to re-established or released AM RLC entities in ascending order of the associated COUNT values for which the successful delivery has not been confirmed by lower layers."

SUMMARY

[0037] Some embodiments provide systems and/or methods for user plane data handling during an SCG de-activation/re-activation procedure. In particular, in some embodiments, upon SCG de-activation, the UE may release the RLC entities associated with the SCG. Upon SCG activation, the UE may establish the RLC entities associated with the SCG and apply a data split threshold associated with the deactivated SCG of infinity.

[0038] In some embodiments, upon SCG activation, the UE may re-establish the RLC entities associated with the SCG. In some embodiments, upon SCG deactivation, the UE may re-establish the RLC entities associated with the SCG.

[0039] Some further embodiments provide that upon SCG de-activation, the UE performs SCG RLC entity data recovery by retransmitting those data in the MCG. This can be done, for example, by initiating a PDCP data recovery. Likewise, upon SCG activation, the UE may perform SCG RLC entity data recovery by retransmitting those data in either MCG or SCG or both. This can be done, for example, by initiating a PDCP data recovery.

[0040] Some further embodiments are provided for the case of a split bearer. For example, during SCG de-activation, the UE may not submit data to the RLC entities associated with the SCG.

[0041] Accordingly, in some embodiments, upon SCG activation, any UL data in the RLC entity at the UE side may be discarded either by RLC entity release/establish or RLC entity re-establishment. The RLC data may be recovered (if needed) by retransmitting it in the PDCP layer (upon either SCG de-activation or activation). In the case of a split bearer, the UE may refrain from transmission using the SCG RLC bearer during SCG de-activation.

[0042] Certain embodiments may provide one or more of the following technical advantage(s). In particular, Some embodiments may help to ensure that there is no stuck RLC data, and may also recover (if possible) data in the upper layer (e.g., PDCP). BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this application, illustrate certain non-limiting embodiments of inventive concepts. In the drawings:

[0044] Figure l is a block diagram that illustrates of dual connectivity combined with carrier aggregation in MR-DC;

[0045] Figure l is a block diagram that illustrates EN-DC;

[0046] Figure 3 is block diagram that illustrates NR-DC;

[0047] Figure 4 illustrates a Control Plane architecture for Dual Connectivity in LTE DC, EN-DC and NR-DC;

[0048] Figure 5 illustrates network-side protocol termination options for MCG, SCG and split DRBs in MR-DC with EPC (EN-DC);

[0049] Figure 6 illustrates network-side protocol termination options for MCG, SCG and split DRBs in MR-DC with 5GC (NGEN-DC, NE-DC and NR-DC);

[0050] Figure 7 illustrates a deactivated SCell and the dormancy like behavior for SCells in NR;

[0051] Figure 8 is a schematic illustration of SCG states in 3GPP Rel-17;

[0052] Figures 9, 10 and 11 are signal flow diagrams that illustrate operations according to some embodiments;

[0053] Figure 12 is a block diagram illustrating a wireless device UE according to some embodiments;

[0054] Figure 13 is a block diagram illustrating a radio access network RAN node (e.g., a base station eNB/gNB) according to some embodiments;

[0055] Figure 14 is a block diagram illustrating a core network CN node (e.g., an AMF node, an SMF node, etc.) according to some embodiments;

[0056] Figures 15, 16 and 17 are flow charts illustrating operations of a communication device according to some embodiments;

[0057] Figure 18 is a block diagram of a communication system in accordance with some embodiments;

[0058] Figure 19 is a block diagram of a user equipment in accordance with some embodiments;

[0059] Figure 20 is a block diagram of a network node in accordance with some embodiments; [0060] Figure 21 is a block diagram of a host computer communicating with a user equipment in accordance with some embodiments;

[0061] Figure 22 is a block diagram of a virtualization environment in accordance with some embodiments; and

[0062] Figure 23 is a block diagram of a host computer communicating via a base station with a user equipment over a partially wireless connection in accordance with some embodiments in accordance with some embodiments.

DETAILED DESCRIPTION

[0063] 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. , in which examples of embodiments of inventive concepts are shown. Inventive concepts may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of present inventive concepts to those skilled in the art. It should also be noted that these embodiments are not mutually exclusive. Components from one embodiment may be tacitly assumed to be present/used in another embodiment.

[0064] In the following discussion, the terms "suspended SCG," "SCG in power saving mode," "SCG deactivated state," or "deactivated SCG" are used interchangeably. A "suspended SCG" may also be referred to as a "deactivated SCG," "inactive SCG," or "dormant SCG." The terms "resumed SCG," "SCG in normal operating mode," "SCG activated state" and "SCG in non-power saving mode" are also used interchangeably. A "resumed SCG" may also be referred to as an "activated SCG" or "active SCG." The operation of an SCG operating in resumed or active mode may also be referred to as normal SCG operation or legacy SCG operation. Examples of operations are UE signal reception/transmission procedures, reception of signals/ messages, transmission of signals/ messages, etc.

[0065] The following description provides examples in which the second cell group is a Secondary Cell Group (SCG) for a UE configured with Multi-Radio Dual Connectivity (e.g. MR-DC).

[0066] The following description uses terms such as SCG and PSCell, as one of the cells associated with the SCG. That can be for example a PSCell as defined in NR specifications (e.g. RRC TS 38.331), defined as a Special Cell (SpCell) of the SCG, or a Primary SCG Cell (PSCell), as follows:

Secondary Cell Group: For a UE configured with dual connectivity, the subset of serving cells comprising of the PSCell and zero or more secondary cells (SCells).

Special Cell: For Dual Connectivity operation the term Special Cell refers to the PCell of the MCG or the PSCell of the SCG, otherwise the term Special Cell refers to the PCell.

Primary SCG Cell (PSCell): For dual connectivity operation, the SCG cell in which the UE performs random access when performing the Reconfiguration with Sync procedure.

[0067] For the sake of brevity, the following description is primarily directed to examples in which the second cell group is a Secondary Cell Group (SCG) that is deactivated (or suspended or in power saving mode of operation), for a UE configured with Multi-Radio Dual Connectivity (e.g. MR-DC). However, embodiments described herein are equally applicable for the case where the second cell group is a Master Cell Group (MCG) for a UE configured with Dual Connectivity (e.g. MR-DC), wherein the MCG could be suspended, while the SCG is operating in normal mode.

[0068] The following description provides that when the second cell group is deactivated (e.g. SCG becomes deactivated upon reception of an indication from the network) the UE stops monitoring PDCCH on the SCG cells (i.e. stops monitoring PDCCH of the PSCell and of the SCells of the SCG). Embodiments are mainly described using as an example a second cell group that is a Secondary Cell Group the UE configured with MR-DC is configured with; and, the SCG being deactivated mode of operation at the UE when the UE perform the actions disclosed in the embodiments. However, some embodiments are also applicable for the case in which the second cell group is a Master Cell Group (MCG) that is deactivated, so that the UE stops monitoring PDCCH on the MCG and continues monitoring PDCCH on the SCG.

[0069] In NR, RLC entities are configured by the field rlc-BearerToAddModList in the IE CellGroupConfig that is used to configure an MCG or an SCG. The RLC entity associated with the SCG is the RLC entity that is configured in the IE CellGroupConfig of the SCG. In the case that the SCG is de-activated while its RLC bearers are not released using rlc- BearerToReleaseList, the corresponding RLC entity is still associated with the SCG. The release of the RLC entity means that the RLC entity is not configured.

[0070] As specified in the clause 5.3.5.5.3 of TS 38.331 RRC, RLC bearer release includes releasing both the RLC entity and the corresponding logical channel. [0071] RLC Entity Release/Establishment

[0072] In a first embodiment, upon SCG de-activation, the UE shall release (or suspend) the RLC entities that are associated with the SCG. The release of the RLC entities also means that all timers are stopped and reset, without initiating any relevant UE actions that would otherwise be applied when the timers are stopped as provided in the specification TS 38.322. In addition, for each such RLC entity that is associated with the SCG, the UE shall discard all RLC SDUs, RLC SDU segments, and RLC PDUs, if any.

[0073] In some embodiments, the upper layers of the RLC layer may, upon SCG deactivation, request an RLC entity release for those RLC entities that are associated with the SCG. The RLC entity release action is specified in TS 38.322.

[0074] In further embodiments, for each such RLC entity associated with the SCG, the UE shall instead deliver received out-of-sequence SDUs to higher layers, if in-sequence delivery on RLC layer is supported. The UE shall still discard RLC SDU segments and RLC PDUs, if any.

[0075] In some embodiments, the above UE actions are applied after the RLC entities change (including the corresponding RLC bearer release, addition, modification) in response to the same RRC message from the network to de-activate the SCG.

[0076] In these embodiment, there will be no RLC SDUs, RLC SDU segments and RLC PDUs in the RLC entity during the time while the SCG is de-activated. Otherwise, upon the SCG activation, those RLC SDUs, RLC SDU segments and RLC PDUs would be delivered first, and which may lead to UE and gNB de-synchronization issue.

[0077] In a second embodiment, upon SCG activation (either by the network indication or the UE autonomous initiation), the UE shall establish (or resume) the RLC entities that are associated with the SCG. In addition, for each such RLC entity that is associated with the SCG, the UE shall set the state variables of the RLC entity to initial values.

[0078] In some embodiments, the upper layers of the RLC layer may, upon SCG activation, request an RLC entity establishment for those RLC entities that are associated with the SCG.

[0079] In some embodiments, the UE actions described above may be applied after the RLC entities change (including RLC bearer release, addition, modification) in the same RRC message (if any) from the network to activate the SCG.

[0080] In another example, the above two embodiments are correspondingly called RLC entity suspend/resume or RLC entity release/establish. [0081] Procedures for RLC entity release/establishment are specified in the 3GPP specification TS 38.331. For establishment of the RLC entities upon SCG activation, it is, however, up-to network implementation on which RLC entities to establish, including only a subset of the RLC entities before SCG de-activation or additional RLC entities.

[0082] An example signalling diagram illustrating the foregoing embodiments is shown in Figure 9. As shown in Figure 9, a UE 600 has an activated SCG at block 902. A gNB 700 sends a message 904 to the UE 600 to deactivate the SCG. In response to the message, the UE releases an RLC entity associated with the SCG but keeps the configuration of the RLC entity at block 906. The gNB 700 then sends a message 908 to activate the deactivated SCG. After activation of the SCG, the UE establishes the RLC entity at block 910.

[0083] RLC entity re-establishment

[0084] In one embodiment, upon the SCG de-activation, the UE shall keep the RLC entities that are associated with the SCG. That is, the UE may take no action for the RLC entities associated with the SCG. Upon SCG activation (either by the network indication or the UE autonomous initiation), the UE shall re-establish the RLC entities that are associated with the SCG. Upon re-establishing the RLC entities, the UE may discard all RLC SDUs, RLC SDU segments, and RLC PDUs, if any, stop and reset all timers, and/or reset all state variables to their initial values.

[0085] In some embodiments, the upper layers of the RLC layer may request an RLC entity re-establishment for those RLC entities that are associated with the SCG, upon the SCG activation.

[0086] In further embodiments, the UE actions described above may be applied after the RLC entities change (including RLC bearer release, addition, modification) in response to the same RRC message (if any) from the network to activate the SCG.

[0087] In some embodiments, the network may set the field reestablishRLC to be true for all RLC entities in the SCG in the cell group configuration of the RRC reconfiguration message that activates/de-activates the SCG.

[0088] An example signalling diagram illustrating the foregoing embodiments is shown in Figure 10. As shown in Figure 10, a UE 600 has an activated SCG at block 1002. A gNB 700 sends a message 1004 to the UE 600 to deactivate the SCG. In response to the message, the UE 600 takes no action on an RLC entity associated with the SCG at block 1006. Optionally, the gNB 700 may send a message 1008 to activate the deactivated SCG. Alternatively, the UE 600 may autonomously activate the SCG. After activation of the SCG, the UE 600 re-establishes the RLC entity at block 1010. [0089] In another embodiment, upon the SCG de-activation (either by the network indication or the UE autonomous initiation), the UE shall re-establish the RLC entities that are associated with the SCG. That is, upon SCG deactivation, the UE may discard all RLC SDUs, RLC SDU segments, and RLC PDUs, if any, stop and reset all timers and/or reset all state variables to their initial values.

[0090] Upon the SCG activation, the UE may keep the RLC entities that are associated with the SCG. That is, no action may be taken for the RLC entities associated with the SCG.

[0091] In some embodiments, the upper layers of the RLC layer request an RLC entity re-establishment for those RLC entities that are associated with the SCG, upon the SCG deactivation.

[0092] In further embodiments, the UE action described above may be applied after the RLC entities change (including RLC bearer release, addition, modification) in response to the same RRC message (if any) from the network to de-activate the SCG.

[0093] An example signalling diagram illustrating the foregoing embodiments is shown in Figure 11. As shown in Figure 11, a UE 600 has an activated SCG at block 1102. A gNB 700 sends a message 1104 to the UE 600 to deactivate the SCG. In response to the message, the UE 600 re-establishes the RLC entity at block 1106. Optionally, the gNB 700 may send a message 1108 to activate the deactivated SCG. Alternatively, the UE 600 may autonomously activate the SCG. After activation of the SCG, the UE 600 takes no action on the RLC entity at block 1110.

[0094] SCG RLC Entity Data Recovery Upon De-activation

[0095] In one embodiment, upon SCG de-activation, a data recovery (e.g., PDCP data recovery) is triggered to recover the data previously submitted to the SCG. This means that for AM DRBs, the transmitting PDCP entity shall perform retransmission of all the PDCP Data/Control PDUs previously submitted to the AM RLC entities associated with the SCG in ascending order of the associated COUNT values for which the successful delivery has not been confirmed by lower layers, following the data submission procedure in the clause 5.2.1 of PDCP spec 38.323. The intention is to retransmit those PDCP PDUs delivered to the RLC entities associated with the SCG in the MCG so that these data are not lost. It is assumed that the UE does not submit the PDCP PDUs to the SCG after the SCG is deactivated and during SCG deactivation.

[0096] In another embodiment, upon SCG activation, a PDCP data recovery for the data previously submitted to the SCG is triggered. This means that for AM DRBs, the transmitting PDCP entity shall perform retransmission of all the PDCP Data/Control PDUs previously submitted to the AM RLC entities associated with the SCG in ascending order of the associated COUNT values for which the successful delivery has not been confirmed by lower layers, following the data submission procedure in clause 5.2.1 of 3GPP TS 38.323.

[0097] This is to ensure that pre-processed RLC SDUs before SCG activation (which might be discarded in the RLC re-establishment procedure) can be retransmitted.

[0098] In one implementation example, if the RLC entities associated with the SCG are re-established/released upon SCG deactivation, then the PDCP data recovery procedure as in the clause 5.5 of TS 38.323 is triggered.

[0099] Split DRBs

[0100] In one embodiment, when the SCG is de-activated, the UE shall not submit the PDCP PDU to the RLC entity that is associated with the SCG. This can be captured, for example, in the clause 5.2.1 of TS 38.323 vl6.5.0, (transmit operation of data transfer), by the revisions shown in Table 1 below:

Table 1 - Revisions to Clause 5.2.1 of TS 38.323

[0101] In another embodiment, when the SCG is de-activated, the UE shall indicate the PDCP data volume as 0 to the MAC entity that is de-activated (i.e., the MAC entity that is associated with the SCG in this case). This can be captured, for example, in the clause 5.6 of PDCP specification TS 38.323 vl6.5.0, (transmit operation of data transfer), by the underlined text in Table 2.

Table 2 - Revisions to Clause 5.6 of TS 38.323

[0102] In another implementation example of the above embodiments, the released RLC entity may be considered as not being configured so that they are not effectively considered in the above procedure text.

[0103] In one embodiment, upon SCG de-activation, the UE applies ul- DataSplitThreshold as the value to be infinity regardless of what has been configured by the network in an RRC message. Upon SCG activation from de-activated state, the UE applies the previously RRC configured ul-DataSplitThreshold value or the RRC configured ul- DataSplitThreshold in the RRC message that also activates the SCG.

[0104] In some embodiments, when SCG is activated, the gNB configures ul- DataSplitThreshold to be one value V-a. After that, upon SCG de-activation, the gNB configures ul-DataSplitThreshold to be infinity. After that, upon SCG activation from the de-activated state, the gNB configures another value other than infinity, for example, the value V-a or another value V-b.

[0105] Figure 12 is a block diagram illustrating elements of a communication device UE 600 (also referred to as a mobile terminal, a mobile communication terminal, a wireless device, a wireless communication device, a wireless terminal, mobile device, a wireless communication terminal, user equipment, UE, a user equipment node/terminal/device, etc.) configured to provide wireless communication according to embodiments of inventive concepts. (Communication device 600 may be provided, for example, as discussed below with respect to wireless devices UE 1812A, UE 1812B, and wired or wireless devices UE 1812C, UE 1812D of Figure 18, UE 1900 of Figure 19, virtualization hardware 2204 and virtual machines 2208 A, 2208B of Figure 22, and UE 2306 of Figure 23, all of which should be considered interchangeable in the examples and embodiments described herein and be within the intended scope of this disclosure, unless otherwise noted.) As shown, communication device UE may include an antenna 607 (e.g., corresponding to antenna 1922 of Figure 19), and transceiver circuitry 601 (also referred to as a transceiver, e.g., corresponding to interface 1912 of Figure 19 having transmitter 1918 and receiver 1920) including a transmitter and a receiver configured to provide uplink and downlink radio communications with a base station(s) (e.g., corresponding to network node 1810A, 1810B of Figure 18, network node 2000 of Figure 20, and network node 2304 of Figure 23 also referred to as a RAN node) of a radio access network. Communication device UE may also include processing circuitry 603 (also referred to as a processor, e.g., corresponding to processing circuitry 1902 of Figure 19, and control system 2212 of Figure 22) coupled to the transceiver circuitry, and memory circuitry 605 (also referred to as memory, e.g., corresponding to memory 1910 of Figure 18) coupled to the processing circuitry. The memory circuitry 605 may include computer readable program code that when executed by the processing circuitry 603 causes the processing circuitry to perform operations according to embodiments disclosed herein. According to other embodiments, processing circuitry 603 may be defined to include memory so that separate memory circuitry is not required. Communication device UE may also include an interface (such as a user interface) coupled with processing circuitry 603, and/or communication device UE may be incorporated in a vehicle.

[0106] As discussed herein, operations of communication device UE may be performed by processing circuitry 603 and/or transceiver circuitry 601. For example, processing circuitry 603 may control transceiver circuitry 601 to transmit communications through transceiver circuitry 601 over a radio interface to a radio access network node (also referred to as a base station) and/or to receive communications through transceiver circuitry 601 from a RAN node over a radio interface. Moreover, modules may be stored in memory circuitry 605, and these modules may provide instructions so that when instructions of a module are executed by processing circuitry 603, processing circuitry 603 performs respective operations (e.g., operations discussed below with respect to Example Embodiments relating to wireless communication devices). According to some embodiments, a communication device UE 600 and/or an element(s)/function(s) thereof may be embodied as a virtual node/nodes and/or a virtual machine/machines.

[0107] Figure 13 is a block diagram illustrating elements of a radio access network RAN node 700 (also referred to as a network node, base station, eNodeB/eNB, gNodeB/gNB, etc.) of a Radio Access Network (RAN) configured to provide cellular communication according to embodiments of inventive concepts. (RAN node 700 may be provided, for example, as discussed below with respect to network node 1810A, 1810B of Figure 18, network node 2000 of Figure 20, hardware 2204 or virtual machine 2208 A, 2208B of Figure 22, and/or base station 2304 of Figure 23, all of which should be considered interchangeable in the examples and embodiments described herein and be within the intended scope of this disclosure, unless otherwise noted.) As shown, the RAN node may include transceiver circuitry 701 (also referred to as a transceiver, e.g., corresponding to portions of RF transceiver circuitry 2012 and radio front end circuitry 2018 of Figure 20) including a transmitter and a receiver configured to provide uplink and downlink radio communications with mobile terminals. The RAN node may include network interface circuitry 707 (also referred to as a network interface, e.g., corresponding to portions of communication interface 2006 of Figure 20) configured to provide communications with other nodes (e.g., with other base stations) of the RAN and/or core network CN. The network node may also include processing circuitry 703 (also referred to as a processor, e.g., corresponding to processing circuitry 2002 of Figure 20) coupled to the transceiver circuitry, and memory circuitry 705 (also referred to as memory, e.g., corresponding to memory 2004 of Figure 20) coupled to the processing circuitry. The memory circuitry 705 may include computer readable program code that when executed by the processing circuitry 703 causes the processing circuitry to perform operations according to embodiments disclosed herein. According to other embodiments, processing circuitry 703 may be defined to include memory so that a separate memory circuitry is not required.

[0108] As discussed herein, operations of the RAN node may be performed by processing circuitry 703, network interface 707, and/or transceiver 701. For example, processing circuitry 703 may control transceiver 701 to transmit downlink communications through transceiver 701 over a radio interface to one or more mobile terminals UEs and/or to receive uplink communications through transceiver 701 from one or more mobile terminals UEs over a radio interface. Similarly, processing circuitry 703 may control network interface 707 to transmit communications through network interface 707 to one or more other network nodes and/or to receive communications through network interface from one or more other network nodes. Moreover, modules may be stored in memory 705, and these modules may provide instructions so that when instructions of a module are executed by processing circuitry 703, processing circuitry 703 performs respective operations (e.g., operations discussed below with respect to Example Embodiments relating to RAN nodes). According to some embodiments, RAN node 700 and/or an element(s)/function(s) thereof may be embodied as a virtual node/nodes and/or a virtual machine/machines.

[0109] According to some other embodiments, a network node may be implemented as a core network CN node without a transceiver. In such embodiments, transmission to a wireless communication device UE may be initiated by the network node so that transmission to the wireless communication device UE is provided through a network node including a transceiver (e.g., through a base station or RAN node). According to embodiments where the network node is a RAN node including a transceiver, initiating transmission may include transmitting through the transceiver. [0110] Figure 14 is a block diagram illustrating elements of a core network (CN) node (e.g., an SMF (session management function) node, an AMF (access and mobility management function) node, etc.) of a communication network configured to provide cellular communication according to embodiments of inventive concepts. (CN node 800 may be provided, for example, as discussed below with respect to core network node 1808 of Figure 18, hardware 2204 or virtual machine 2208 A, 2208B of Figure 22, all of which should be considered interchangeable in the examples and embodiments described herein and be within the intended scope of this disclosure, unless otherwise noted) As shown, the CN node may include network interface circuitry 807 configured to provide communications with other nodes of the core network and/or the radio access network RAN. The CN node may also include a processing circuitry 803 (also referred to as a processor,) coupled to the network interface circuitry, and memory circuitry 805 (also referred to as memory) coupled to the processing circuitry. The memory circuitry 805 may include computer readable program code that when executed by the processing circuitry 803 causes the processing circuitry to perform operations according to embodiments disclosed herein. According to other embodiments, processing circuitry 803 may be defined to include memory so that a separate memory circuitry is not required.

[OHl] As discussed herein, operations of the CN node may be performed by processing circuitry 803 and/or network interface circuitry 807. For example, processing circuitry 803 may control network interface circuitry 807 to transmit communications through network interface circuitry 807 to one or more other network nodes and/or to receive communications through network interface circuitry from one or more other network nodes. Moreover, modules may be stored in memory 805, and these modules may provide instructions so that when instructions of a module are executed by processing circuitry 803, processing circuitry 803 performs respective operations (e.g., operations discussed below with respect to Example Embodiments relating to core network nodes). According to some embodiments, CN node 800 and/or an element(s)/function(s) thereof may be embodied as a virtual node/nodes and/or a virtual machine/machines.

[0112] In the description that follows, while the communication device may be any of the communication device 600, wireless device 1812A, 1812B, wired or wireless devices UE 1812C, UE 1812D, UE 1900, virtualization hardware 2204, virtual machines 2208 A, 2208B, or UE 2306, the communication device 600 shall be used to describe the functionality of the operations of the communication device. Operations of the communication device 600 (implemented using the structure of the block diagram of Figure 12) will now be discussed with reference to the flow charts of Figures 15, 16 and 17 according to some embodiments of inventive concepts. For example, modules may be stored in memory 605 of Figure 12, and these modules may provide instructions so that when the instructions of a module are executed by respective communication device processing circuitry 603, processing circuitry 603 performs respective operations of the flow chart.

[0113] Figure 15 illustrates a method of operating a user equipment according to some embodiments. The method includes deactivating (block 1502) an active secondary cell group, SCG, and in response to deactivating the active SCG, releasing (block 1504) a radio link control, RLC, entity associated with the SCG.

[0114] Releasing the RLC entity may include stopping and resetting a timer associated with the RLC entity. The timer may be stopped and reset without initiating any action associated with the timer.

[0115] Releasing the RLC entity may include discarding RLC service data units, SDUs, SDU segments, and/or protocol data units, PDUs of the RLC entity.

[0116] In some embodiments, upper layers of an RLC layer request release of the RLC entity in response to deactivation of the SCG.

[0117] The method may further include delivering out-of-sequence service data units, SDUs, of the RLC entity to higher layers in response to deactivation of the SCG.

[0118] Deactivating the SCG may be performed in response to a radio resource control, RRC, message.

[0119] The method may further include activating the deactivated SCG, and in response to activating the deactivated SCG, establishing or resuming the RLC entity associated with the SCG.

[0120] The method may further include in response to activating the deactivated SCG, performing SCG RLC data recovery. Performing SCG RLC data recovery may include initiating a packet data convergence protocol, PDCP, data recovery procedure. Performing SCG RLC data recovery may include transmitting stored RLC packets associated with the activated SCG in the SCG or in a master cell group, MCG.

[0121] The method may further include, upon establishing or resuming the RLC entity, setting state variables associated with the RLC entity to initial values.

[0122] Establishing or resuming the RLC entity may be performed in response to a request from higher layers above the RLC layer.

[0123] The method may further include activating the deactivated SCG, and in response to activating the deactivated SCG, re-establishing the RLC entity associated with the SCG. [0124] The method may further include re-establishing the RLC entity associated with the SCG in response to de-activating the active SCG.

[0125] The method may further include in response to deactivating the active SCG, performing SCG RLC data recovery. Performing SCG RLC data recovery may include transmitting stored RLC packets associated with the deactivated SCG in a master cell group, MCG. Performing SCG RLC data recovery may include initiating a packet data convergence protocol, PDCP, data recovery procedure.

[0126] The method may further include receiving a packet data convergence protocol, PDCP, protocol data unit, PDU, after deactivation of the SCG, and submitting the PDCP PDU to an RLC entity that may be not associated with the deactivated SCG.

[0127] The method may further include indicating to a medium access control, MAC, entity associated with the deactivated SCG that a PDCP volume associated with the deactivated SCG may be zero.

[0128] The method may further include applying a data split threshold associated with the deactivated SCG of infinity. A data split threshold is a variable that is configured by the network. In a split DRB scenario, data can be sent over an SCG or a MCG. When the data split threshold is configured, if the data volume is larger than the data split threshold, the UE can transmit data on the SCG. Setting the data split threshold to infinity ensures that the UE will not attempt to transmit data on the SCG.

[0129] Figure 16 illustrates a method of operating a user equipment according to further embodiments. The method includes deactivating (block 1602) an active secondary cell group, SCG, in response to deactivating the active SCG, taking no action (block 1604) on a radio link control, RLC, entity associated with the SCG, activating (block 1606) the deactivated SCG, and in response to activating the deactivated SCG, re-establishing (block 1608) the RLC entity associated with the SCG.

[0130] Re-establishing the RLC entity may include stopping and resetting a timer associated with the RLC entity.

[0131] The timer may be stopped and reset without initiating any action associated with the timer.

[0132] Re-establishing the RLC entity may include discarding RLC service data units, SDUs, SDU segments, and/or protocol data units, PDUs of the RLC entity.

[0133] Re-establishing the RLC entity may include resetting state variables associated with the RLC entity to initial values. [0134] The method may further include receiving a packet data convergence protocol, PDCP, protocol data unit, PDU, after deactivation of the SCG, and submitting the PDCP PDU to an RLC entity that may be not associated with the deactivated SCG.

[0135] The method may further include indicating to a medium access control, MAC, entity associated with the deactivated SCG that a PDCP volume associated with the deactivated SCG may be zero.

[0136] The method may further include applying a data split threshold associated with the deactivated SCG of infinity.

[0137] Figure 17 illustrates a method of operating a user equipment according to further embodiments. The method includes deactivating (block 1702) an active secondary cell group, SCG, and in response to deactivating the active SCG, re-stabli shing (block 1704) a radio link control, RLC, entity associated with the SCG.

[0138] Re-establishing the RLC entity may include stopping and resetting a timer associated with the RLC entity.

[0139] The timer may be stopped and reset without initiating any action associated with the timer.

[0140] Re-establishing the RLC entity may include discarding RLC service data units, SDUs, SDU segments, and/or protocol data units, PDUs of the RLC entity.

[0141] Re-establishing the RLC entity may include resetting state variables associated with the RLC entity to initial values.

[0142] The method may further include receiving a packet data convergence protocol, PDCP, protocol data unit, PDU, after deactivation of the SCG, and submitting the PDCP PDU to an RLC entity that may be not associated with the deactivated SCG.

[0143] The method may further include indicating to a medium access control, MAC, entity associated with the deactivated SCG that a PDCP volume associated with the deactivated SCG may be zero.

[0144] The method may further include applying a data split threshold associated with the deactivated SCG of infinity.

[0145] Figure 18 shows an example of a communication system 1800 in accordance with some embodiments.

[0146] In the example, the communication system 1800 includes a telecommunication network 1802 that includes an access network 1804, such as a radio access network (RAN), and a core network 1806, which includes one or more core network nodes 1808. The access network 1804 includes one or more access network nodes, such as network nodes 1810a and 1810b (one or more of which may be generally referred to as network nodes 1810), or any other similar 3^rd Generation Partnership Project (3 GPP) access node or non-3GPP access point. The network nodes 1810 facilitate direct or indirect connection of user equipment (UE), such as by connecting UEs 1812a, 1812b, 1812c, and 1812d (one or more of which may be generally referred to as UEs 1812) to the core network 1806 over one or more wireless connections.

[0147] 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 1800 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 1800 may include and/or interface with any type of communication, telecommunication, data, cellular, radio network, and/or other similar type of system.

[0148] The UEs 1812 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 1810 and other communication devices. Similarly, the network nodes 1810 are arranged, capable, configured, and/or operable to communicate directly or indirectly with the UEs 1812 and/or with other network nodes or equipment in the telecommunication network 1802 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 1802.

[0149] In the depicted example, the core network 1806 connects the network nodes 1810 to one or more hosts, such as host 1816. 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 1806 includes one more core network nodes (e.g., core network node 1808) 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 1808. 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).

[0150] The host 1816 may be under the ownership or control of a service provider other than an operator or provider of the access network 1804 and/or the telecommunication network 1802, and may be operated by the service provider or on behalf of the service provider. The host 1816 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.

[0151] As a whole, the communication system 1800 of Figure 18 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.

[0152] In some examples, the telecommunication network 1802 is a cellular network that implements 3GPP standardized features. Accordingly, the telecommunications network 1802 may support network slicing to provide different logical networks to different devices that are connected to the telecommunication network 1802. For example, the telecommunications network 1802 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.

[0153] In some examples, the UEs 1812 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 1804 on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the access network 1804. 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).

[0154] In the example, the hub 1814 communicates with the access network 1804 to facilitate indirect communication between one or more UEs (e.g., UE 1812c and/or 1812d) and network nodes (e.g., network node 1810b). In some examples, the hub 1814 may be a controller, router, content source and analytics, or any of the other communication devices described herein regarding UEs. For example, the hub 1814 may be a broadband router enabling access to the core network 1806 for the UEs. As another example, the hub 1814 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 1810, or by executable code, script, process, or other instructions in the hub 1814. As another example, the hub 1814 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 1814 may be a content source. For example, for a UE that is a VR headset, display, loudspeaker or other media delivery device, the hub 1814 may retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, which the hub 1814 then provides to the UE either directly, after performing local processing, and/or after adding additional local content. In still another example, the hub 1814 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.

[0155] The hub 1814 may have a constant/persistent or intermittent connection to the network node 1810b. The hub 1814 may also allow for a different communication scheme and/or schedule between the hub 1814 and UEs (e.g., UE 1812c and/or 1812d), and between the hub 1814 and the core network 1806. In other examples, the hub 1814 is connected to the core network 1806 and/or one or more UEs via a wired connection. Moreover, the hub 1814 may be configured to connect to an M2M service provider over the access network 1804 and/or to another UE over a direct connection. In some scenarios, UEs may establish a wireless connection with the network nodes 1810 while still connected via the hub 1814 via a wired or wireless connection. In some embodiments, the hub 1814 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 1810b. In other embodiments, the hub 1814 may be a non-dedicated hub - that is, a device which is capable of operating to route communications between the UEs and network node 1810b, but which is additionally capable of operating as a communication start and/or end point for certain data channels. [0156] Figure 19 shows a UE 1900 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 (3 GPP), including a narrow band internet of things (NB-IoT) UE, a machine type communication (MTC) UE, and/or an enhanced MTC (eMTC) UE.

[0157] A UE may support device-to-device (D2D) communication, for example by implementing a 3 GPP 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).

[0158] The UE 1900 includes processing circuitry 1902 that is operatively coupled via a bus 1904 to an input/output interface 1906, a power source 1908, a memory 1910, a communication interface 1912, and/or any other component, or any combination thereof. Certain UEs may utilize all or a subset of the components shown in Figure 19. 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.

[0159] The processing circuitry 1902 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 1910. The processing circuitry 1902 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 1902 may include multiple central processing units (CPUs).

[0160] In the example, the input/output interface 1906 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 1900. 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.

[0161] In some embodiments, the power source 1908 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 1908 may further include power circuitry for delivering power from the power source 1908 itself, and/or an external power source, to the various parts of the UE 1900 via input circuitry or an interface such as an electrical power cable. Delivering power may be, for example, for charging of the power source 1908. Power circuitry may perform any formatting, converting, or other modification to the power from the power source 1908 to make the power suitable for the respective components of the UE 1900 to which power is supplied.

[0162] The memory 1910 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 readonly memory (EEPROM), magnetic disks, optical disks, hard disks, removable cartridges, flash drives, and so forth. In one example, the memory 1910 includes one or more application programs 1914, such as an operating system, web browser application, a widget, gadget engine, or other application, and corresponding data 1916. The memory 1910 may store, for use by the UE 1900, any of a variety of various operating systems or combinations of operating systems. [0163] The memory 1910 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 1910 may allow the UE 1900 to access instructions, application programs and the like, stored on transitory or non-transitory memory media, to offload 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 1910, which may be or comprise a device-readable storage medium.

[0164] The processing circuitry 1902 may be configured to communicate with an access network or other network using the communication interface 1912. The communication interface 1912 may comprise one or more communication subsystems and may include or be communicatively coupled to an antenna 1922. The communication interface 1912 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 1918 and/or a receiver 1920 appropriate to provide network communications (e.g., optical, electrical, frequency allocations, and so forth). Moreover, the transmitter 1918 and receiver 1920 may be coupled to one or more antennas (e.g., antenna 1922) and may share circuit components, software or firmware, or alternatively be implemented separately.

[0165] In the illustrated embodiment, communication functions of the communication interface 1912 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.

[0166] Regardless of the type of sensor, a UE may provide an output of data captured by its sensors, through its communication interface 1912, 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).

[0167] 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.

[0168] 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 item-tracking 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 1900 shown in Figure 19. [0169] 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.

[0170] 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.

[0171] Figure 20 shows a network node 2000 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)).

[0172] 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).

[0173] 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/multicast 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).

[0174] The network node 2000 includes a processing circuitry 2002, a memory 2004, a communication interface 2006, and a power source 2008. The network node 2000 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 2000 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 NodeB s. 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 2000 may be configured to support multiple radio access technologies (RATs). In such embodiments, some components may be duplicated (e.g., separate memory 2004 for different RATs) and some components may be reused (e.g., a same antenna 2010 may be shared by different RATs). The network node 2000 may also include multiple sets of the various illustrated components for different wireless technologies integrated into network node 2000, 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 2000.

[0175] The processing circuitry 2002 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 2000 components, such as the memory 2004, to provide network node 2000 functionality.

[0176] In some embodiments, the processing circuitry 2002 includes a system on a chip (SOC). In some embodiments, the processing circuitry 2002 includes one or more of radio frequency (RF) transceiver circuitry 2012 and baseband processing circuitry 2014. In some embodiments, the radio frequency (RF) transceiver circuitry 2012 and the baseband processing circuitry 2014 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 2012 and baseband processing circuitry 2014 may be on the same chip or set of chips, boards, or units. [0177] The memory 2004 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 2002. The memory 2004 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 2002 and utilized by the network node 2000. The memory 2004 may be used to store any calculations made by the processing circuitry 2002 and/or any data received via the communication interface 2006. In some embodiments, the processing circuitry 2002 and memory 2004 is integrated.

[0178] The communication interface 2006 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 2006 comprises port(s)/terminal(s) 2016 to send and receive data, for example to and from a network over a wired connection. The communication interface 2006 also includes radio front-end circuitry 2018 that may be coupled to, or in certain embodiments a part of, the antenna 2010. Radio front-end circuitry 2018 comprises filters 2020 and amplifiers 2022. The radio front-end circuitry 2018 may be connected to an antenna 2010 and processing circuitry 2002. The radio front-end circuitry may be configured to condition signals communicated between antenna 2010 and processing circuitry 2002. The radio front-end circuitry 2018 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 2018 may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of filters 2020 and/or amplifiers 2022. The radio signal may then be transmitted via the antenna 2010. Similarly, when receiving data, the antenna 2010 may collect radio signals which are then converted into digital data by the radio front-end circuitry 2018. The digital data may be passed to the processing circuitry 2002. In other embodiments, the communication interface may comprise different components and/or different combinations of components.

[0179] In certain alternative embodiments, the network node 2000 does not include separate radio front-end circuitry 2018, instead, the processing circuitry 2002 includes radio front-end circuitry and is connected to the antenna 2010. Similarly, in some embodiments, all or some of the RF transceiver circuitry 2012 is part of the communication interface 2006. In still other embodiments, the communication interface 2006 includes one or more ports or terminals 2016, the radio front-end circuitry 2018, and the RF transceiver circuitry 2012, as part of a radio unit (not shown), and the communication interface 2006 communicates with the baseband processing circuitry 2014, which is part of a digital unit (not shown).

[0180] The antenna 2010 may include one or more antennas, or antenna arrays, configured to send and/or receive wireless signals. The antenna 2010 may be coupled to the radio front-end circuitry 2018 and may be any type of antenna capable of transmitting and receiving data and/or signals wirelessly. In certain embodiments, the antenna 2010 is separate from the network node 2000 and connectable to the network node 2000 through an interface or port.

[0181] The antenna 2010, communication interface 2006, and/or the processing circuitry 2002 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 2010, the communication interface 2006, and/or the processing circuitry 2002 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.

[0182] The power source 2008 provides power to the various components of network node 2000 in a form suitable for the respective components (e.g., at a voltage and current level needed for each respective component). The power source 2008 may further comprise, or be coupled to, power management circuitry to supply the components of the network node 2000 with power for performing the functionality described herein. For example, the network node 2000 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 2008. As a further example, the power source 2008 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.

[0183] Embodiments of the network node 2000 may include additional components beyond those shown in Figure 20 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 2000 may include user interface equipment to allow input of information into the network node 2000 and to allow output of information from the network node 2000. This may allow a user to perform diagnostic, maintenance, repair, and other administrative functions for the network node 2000.

[0184] Figure 21 is a block diagram of a host 2100, which may be an embodiment of the host 1816 of Figure 18, in accordance with various aspects described herein. As used herein, the host 2100 may be or comprise various combinations hardware and/or software, including a standalone server, a blade server, a cloud-implemented server, a distributed server, a virtual machine, container, or processing resources in a server farm. The host 2100 may provide one or more services to one or more UEs.

[0185] The host 2100 includes processing circuitry 2102 that is operatively coupled via a bus 2104 to an input/output interface 2106, a network interface 2108, a power source 2110, and a memory 2112. Other components may be included in other embodiments. Features of these components may be substantially similar to those described with respect to the devices of previous figures, such as Figures 19 and 20, such that the descriptions thereof are generally applicable to the corresponding components of host 2100.

[0186] The memory 2112 may include one or more computer programs including one or more host application programs 2114 and data 2116, which may include user data, e.g., data generated by a UE for the host 2100 or data generated by the host 2100 for a UE. Embodiments of the host 2100 may utilize only a subset or all of the components shown. The host application programs 2114 may be implemented in a container-based architecture and may provide support for video codecs (e.g., Versatile Video Coding (VVC), High Efficiency Video Coding (HEVC), Advanced Video Coding (AVC), MPEG, VP9) and audio codecs (e.g., FLAC, Advanced Audio Coding (AAC), MPEG, G.711), including transcoding for multiple different classes, types, or implementations of UEs (e.g., handsets, desktop computers, wearable display systems, heads-up display systems). The host application programs 2114 may also provide for user authentication and licensing checks and may periodically report health, routes, and content availability to a central node, such as a device in or on the edge of a core network. Accordingly, the host 2100 may select and/or indicate a different host for over-the-top services for a UE. The host application programs 2114 may support various protocols, such as the HTTP Live Streaming (HLS) protocol, Real-Time Messaging Protocol (RTMP), Real-Time Streaming Protocol (RTSP), Dynamic Adaptive Streaming over HTTP (MPEG-DASH), etc.

[0187] Figure 22 is a block diagram illustrating a virtualization environment 2200 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 2200 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.

[0188] Applications 2202 (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.

[0189] Hardware 2204 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 2206 (also referred to as hypervisors or virtual machine monitors (VMMs)), provide VMs 2208a and 2208b (one or more of which may be generally referred to as VMs 2208), and/or perform any of the functions, features and/or benefits described in relation with some embodiments described herein. The virtualization layer 2206 may present a virtual operating platform that appears like networking hardware to the VMs 2208.

[0190] The VMs 2208 comprise virtual processing, virtual memory, virtual networking or interface and virtual storage, and may be run by a corresponding virtualization layer 2206. Different embodiments of the instance of a virtual appliance 2202 may be implemented on one or more of VMs 2208, 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.

[0191] In the context of NFV, a VM 2208 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 2208, and that part of hardware 2204 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 2208 on top of the hardware 2204 and corresponds to the application 2202.

[0192] Hardware 2204 may be implemented in a standalone network node with generic or specific components. Hardware 2204 may implement some functions via virtualization. Alternatively, hardware 2204 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 2210, which, among others, oversees lifecycle management of applications 2202. In some embodiments, hardware 2204 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 2212 which may alternatively be used for communication between hardware nodes and radio units.

[0193] Figure 23 shows a communication diagram of a host 2302 communicating via a network node 2304 with a UE 2306 over a partially wireless connection in accordance with some embodiments. Example implementations, in accordance with various embodiments, of the UE (such as a UE 1812a of Figure 18 and/or UE 1900 of Figure 19), network node (such as network node 1810a of Figure 18 and/or network node 2000 of Figure 20), and host (such as host 1816 of Figure 18 and/or host 2100 of Figure 21) discussed in the preceding paragraphs will now be described with reference to Figure 23.

[0194] Like host 2100, embodiments of host 2302 include hardware, such as a communication interface, processing circuitry, and memory. The host 2302 also includes software, which is stored in or accessible by the host 2302 and executable by the processing circuitry. The software includes a host application that may be operable to provide a service to a remote user, such as the UE 2306 connecting via an over-the-top (OTT) connection 2350 extending between the UE 2306 and host 2302. In providing the service to the remote user, a host application may provide user data which is transmitted using the OTT connection 2350.

[0195] The network node 2304 includes hardware enabling it to communicate with the host 2302 and UE 2306. The connection 2360 may be direct or pass through a core network (like core network 1806 of Figure 18) and/or one or more other intermediate networks, such as one or more public, private, or hosted networks. For example, an intermediate network may be a backbone network or the Internet.

[0196] The UE 2306 includes hardware and software, which is stored in or accessible by UE 2306 and executable by the UE’s processing circuitry. The software includes a client application, such as a web browser or operator-specific “app” that may be operable to provide a service to a human or non-human user via UE 2306 with the support of the host 2302. In the host 2302, an executing host application may communicate with the executing client application via the OTT connection 2350 terminating at the UE 2306 and host 2302. In providing the service to the user, the UE's client application may receive request data from the host's host application and provide user data in response to the request data. The OTT connection 2350 may transfer both the request data and the user data. The UE's client application may interact with the user to generate the user data that it provides to the host application through the OTT connection 2350.

[0197] The OTT connection 2350 may extend via a connection 2360 between the host 2302 and the network node 2304 and via a wireless connection 2370 between the network node 2304 and the UE 2306 to provide the connection between the host 2302 and the UE 2306. The connection 2360 and wireless connection 2370, over which the OTT connection 2350 may be provided, have been drawn abstractly to illustrate the communication between the host 2302 and the UE 2306 via the network node 2304, without explicit reference to any intermediary devices and the precise routing of messages via these devices.

[0198] As an example of transmitting data via the OTT connection 2350, in step 2308, the host 2302 provides user data, which may be performed by executing a host application. In some embodiments, the user data is associated with a particular human user interacting with the UE 2306. In other embodiments, the user data is associated with a UE 2306 that shares data with the host 2302 without explicit human interaction. In step 2310, the host 2302 initiates a transmission carrying the user data towards the UE 2306. The host 2302 may initiate the transmission responsive to a request transmitted by the UE 2306. The request may be caused by human interaction with the UE 2306 or by operation of the client application executing on the UE 2306. The transmission may pass via the network node 2304, in accordance with the teachings of the embodiments described throughout this disclosure. Accordingly, in step 2312, the network node 2304 transmits to the UE 2306 the user data that was carried in the transmission that the host 2302 initiated, in accordance with the teachings of the embodiments described throughout this disclosure. In step 2314, the UE 2306 receives the user data carried in the transmission, which may be performed by a client application executed on the UE 2306 associated with the host application executed by the host 2302. [0199] In some examples, the UE 2306 executes a client application which provides user data to the host 2302. The user data may be provided in reaction or response to the data received from the host 2302. Accordingly, in step 2316, the UE 2306 may provide user data, which may be performed by executing the client application. In providing the user data, the client application may further consider user input received from the user via an input/output interface of the UE 2306. Regardless of the specific manner in which the user data was provided, the UE 2306 initiates, in step 2318, transmission of the user data towards the host 2302 via the network node 2304. In step 2320, in accordance with the teachings of the embodiments described throughout this disclosure, the network node 2304 receives user data from the UE 2306 and initiates transmission of the received user data towards the host 2302. In step 2322, the host 2302 receives the user data carried in the transmission initiated by the UE 2306.

[0200] One or more of the various embodiments improve the performance of OTT services provided to the UE 2306 using the OTT connection 2350, in which the wireless connection 2370 forms the last segment. More precisely, the teachings of these embodiments may improve the efficiency of SCG activation/deactivation procedures and thereby provide benefits such as reduced signalling overhead and/or avoidance of loss or retransmission of data packets.

[0201] In an example scenario, factory status information may be collected and analyzed by the host 2302. As another example, the host 2302 may process audio and video data which may have been retrieved from a UE for use in creating maps. As another example, the host 2302 may collect and analyze real-time data to assist in controlling vehicle congestion (e.g., controlling traffic lights). As another example, the host 2302 may store surveillance video uploaded by a UE. As another example, the host 2302 may store or control access to media content such as video, audio, VR or AR which it can broadcast, multicast or unicast to UEs. As other examples, the host 2302 may be used for energy pricing, remote control of non-time critical electrical load to balance power generation needs, location services, presentation services (such as compiling diagrams etc. from data collected from remote devices), or any other function of collecting, retrieving, storing, analyzing and/or transmitting data.

[0202] In some examples, a measurement procedure may be provided for the purpose of monitoring data rate, latency and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring the OTT connection 2350 between the host 2302 and UE 2306, in response to variations in the measurement results. The measurement procedure and/or the network functionality for reconfiguring the OTT connection may be implemented in software and hardware of the host 2302 and/or UE 2306. In some embodiments, sensors (not shown) may be deployed in or in association with other devices through which the OTT connection 2350 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or supplying values of other physical quantities from which software may compute or estimate the monitored quantities. The reconfiguring of the OTT connection 2350 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not directly alter the operation of the network node 2304. Such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signaling that facilitates measurements of throughput, propagation times, latency and the like, by the host 2302. The measurements may be implemented in that software causes messages to be transmitted, in particular empty or ‘dummy’ messages, using the OTT connection 2350 while monitoring propagation times, errors, etc.

[0203] 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.

[0204] 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 functionality 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.

[0205] Further definitions and embodiments are discussed below.

[0206] In the above-description of various embodiments of present inventive concepts, it is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of present inventive concepts. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which present inventive concepts belong. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of this specification and the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0207] When an element is referred to as being "connected", "coupled", "responsive", or variants thereof to another element, it can be directly connected, coupled, or responsive to the other element or intervening elements may be present. In contrast, when an element is referred to as being "directly connected", "directly coupled", "directly responsive", or variants thereof to another element, there are no intervening elements present. Like numbers refer to like elements throughout. Furthermore, "coupled", "connected", "responsive", or variants thereof as used herein may include wirelessly coupled, connected, or responsive. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. Well-known functions or constructions may not be described in detail for brevity and/or clarity. The term "and/or" (abbreviated “/”) includes any and all combinations of one or more of the associated listed items.

[0208] It will be understood that although the terms first, second, third, etc. may be used herein to describe various elements/operations, these elements/operations should not be limited by these terms. These terms are only used to distinguish one element/operation from another element/operation. Thus a first element/operation in some embodiments could be termed a second element/operation in other embodiments without departing from the teachings of present inventive concepts. The same reference numerals or the same reference designators denote the same or similar elements throughout the specification.

[0209] As used herein, the terms "comprise", "comprising", "comprises", "include", "including", "includes", "have", "has", "having", or variants thereof are open-ended, and include one or more stated features, integers, elements, steps, components or functions but does not preclude the presence or addition of one or more other features, integers, elements, steps, components, functions or groups thereof. Furthermore, as used herein, the common abbreviation "e.g.", which derives from the Latin phrase "exempli gratia," may be used to introduce or specify a general example or examples of a previously mentioned item, and is not intended to be limiting of such item. The common abbreviation "i.e.", which derives from the Latin phrase "id est," may be used to specify a particular item from a more general recitation.

[0210] Example embodiments are described herein with reference to block diagrams and/or flowchart illustrations of computer-implemented methods, apparatus (systems and/or devices) and/or computer program products. It is understood that a block of the block diagrams and/or flowchart illustrations, and combinations of blocks in the block diagrams and/or flowchart illustrations, can be implemented by computer program instructions that are performed by one or more computer circuits. These computer program instructions may be provided to a processor circuit of a general purpose computer circuit, special purpose computer circuit, and/or other programmable data processing circuit to produce a machine, such that the instructions, which execute via the processor of the computer and/or other programmable data processing apparatus, transform and control transistors, values stored in memory locations, and other hardware components within such circuitry to implement the functions/acts specified in the block diagrams and/or flowchart block or blocks, and thereby create means (functionality) and/or structure for implementing the functions/acts specified in the block diagrams and/or flowchart block(s).

[0211] These computer program instructions may also be stored in a tangible computer-readable medium that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer- readable medium produce an article of manufacture including instructions which implement the functions/acts specified in the block diagrams and/or flowchart block or blocks. Accordingly, embodiments of present inventive concepts may be embodied in hardware and/or in software (including firmware, resident software, micro-code, etc.) that runs on a processor such as a digital signal processor, which may collectively be referred to as "circuitry," "a module" or variants thereof. [0212] It should also be noted that in some alternate implementations, the functions/acts noted in the blocks may occur out of the order noted in the flowcharts. For example, two blocks shown in succession may in fact be executed substantially concurrently or the blocks may sometimes be executed in the reverse order, depending upon the functionality/acts involved. Moreover, the functionality of a given block of the flowcharts and/or block diagrams may be separated into multiple blocks and/or the functionality of two or more blocks of the flowcharts and/or block diagrams may be at least partially integrated. Finally, other blocks may be added/inserted between the blocks that are illustrated, and/or blocks/operations may be omitted without departing from the scope of inventive concepts. Moreover, although some of the diagrams include arrows on communication paths to show a primary direction of communication, it is to be understood that communication may occur in the opposite direction to the depicted arrows.

[0213] Many variations and modifications can be made to the embodiments without substantially departing from the principles of the present inventive concepts. All such variations and modifications are intended to be included herein within the scope of present inventive concepts. Accordingly, the above disclosed subject matter is to be considered illustrative, and not restrictive, and the examples of embodiments are intended to cover all such modifications, enhancements, and other embodiments, which fall within the spirit and scope of present inventive concepts. Thus, to the maximum extent allowed by law, the scope of present inventive concepts are to be determined by the broadest permissible interpretation of the present disclosure including the examples of embodiments and their equivalents, and shall not be restricted or limited by the foregoing detailed description.

[0214] Explanations are provided below for various abbreviations/acronyms used in the present disclosure.

Abbreviation Explanation

5GC or 5GCN 5G core network

ACK Acknowledgement

AGC Automatic Gain Control

Al Artificial Intelligence

AM Acknowledged Mode

AMF Access and Mobility management Function AP Application Protocol

BSR Buffer Status Report

BWP Bandwidth Part

C-RNTI Cell Radio Network Temporary Identifier

CA Carrier Aggregation

CE Control Element

CHO Conditional Handover

CN Core Network

CPA Conditional PSCell Addition

CPC Conditional PSCell Change

CP Control Plane

CQI Channel Quality Indicator

C-RNTI Cell Radio Network Temporary Identifier

CSI Channel State Information

DC Dual Connectivity

DCI Downlink Control Information

DL Downlink

DRB Data Radio Bearer eNB (EUTRAN) base station

EPC Evolved Packet Core

E-RAB EUTRAN Radio Access Bearer

E-UTRA Evolved Universal Terrestrial Radio Access

E-UTRAN Evolved Universal Terrestrial Radio Access Network

FDD Frequency Division Duplex gNB NR base station

GTP-U GPRS Tunneling Protocol - User Plane

IE Information Element

IP Internet Protocol

LTE Long Term Evolution

MCG Master Cell Group

MAC Medium Access Control

MAC CE MAC Control Element

MeNB Master eNB

MgNB Master gNB ML Machine Learning

MN Master Node

MR-DC Multi-Radio Dual Connectivity

NACK Negative Acknowledgement

NAS Non Access Stratum

NG-RAN Next Generation Radio Access Network

Ng-eNB Next Generation Evolved Node B

NR New Radio

PDCP Packet Data Convergence Protocol

PCell Primary Cell

PCI Physical Cell Identity

PDCCH Physical Downlink Control Channel

PDU Protocol Data Unit

PHR Power headroom report

PSCell Primary Secondary Cell (in LTE) or Primary SCG Cell (in NR)

PUCCH Physical Uplink Control Channel

PUSCH Phyical Uplink Shared Channel

RAT Radio Access Technology

RB Radio Bearer

RLC Radio Link Control

RLE Radio Link Failure

RRC Radio Resource Control

SCell Secondary Cell

SCG Secondary Cell Group

SCTP Stream Control Transmission Protocol

SDU Service Data Unit

SeNB Secondary eNB

SgNB Secondary gNB

SINR Signal to Interference plus Noise Ratio

SN Secondary Node

SR Scheduling Request

SRB Signaling Radio Bearer

S-SN Source Secondary Node

SUL Supplementary uplink SpCell Special Cell, the primary cell of a master or secondary cell group

TDD Time Division Duplex

TEID Tunnel Endpoint IDentifier

TNL Transport Network Layer

T- SN Target S econdary Node

UCI Uplink Control Information

UDP User Datagram Protocol

UPF User Plane Function

UE User Equipment

UL Uplink

UL-SCH Uplink Shared Channel

UP User Plane

URLLC Ultra Reliable Low Latency Communication

X2 Interface between base stations

[0215] References are identified below

[1] 38.323 V16.5.0

[2] 38.322 V16.2.0

[3] 38.331 V16.6.0

Claims

Claims:

1. A method of operating a user equipment, comprising: deactivating (1502) an active secondary cell group, SCG; upon deactivating the active SCG, releasing (1504) a radio link control, RLC, entity associated with the SCG; and applying a data split threshold associated with the deactivated SCG of infinity.

2. The method of Claim 1, further comprising: activating the deactivated SCG; and upon activating the deactivated SCG, establishing the RLC entity associated with the SCG

3. The method of Claim 1, further comprising: upon deactivating the active SCG, performing packet data convergence protocol, PDCP, data recovery.

4. The method of Claim 3, wherein performing PDCP data recovery comprises initiating a PDCP data recovery procedure.

5. The method of Claim 3, wherein performing PDCP data recovery comprises transmitting stored RLC packets associated with the activated SCG in the SCG or in a master cell group, MCG.

6. The method of Claim 2, further comprising: upon establishing or resuming the RLC entity, setting state variables associated with the RLC entity to initial values.

7. The method of any of Claims 2 to 6, wherein establishing or resuming the RLC entity is performed in response to a request from higher layers above the RLC layer.

8. The method of any previous Claim, further comprising:

46 upon deactivating the active SCG, performing SCG RLC data recovery.

9. The method of Claim 8, wherein performing SCG RLC data recovery comprises transmitting stored RLC packets associated with the deactivated SCG in a master cell group, MCG.

10. The method of Claim 8, wherein performing SCG RLC data recovery comprises initiating a packet data convergence protocol, PDCP, data recovery procedure.

11. The method of any previous claim, wherein releasing the RLC entity associated with the SCG is performed in response to a network configuration.

12. A method of operating a user equipment, comprising: deactivating (1602) an active secondary cell group, SCG; and taking no action (1604) on a radio link control, RLC, entity associated with the SCG upon deactivating the active SCG; activating (1606) the deactivated SCG; and upon activating the deactivated SCG, re-establishing (1608) the RLC entity associated with the SCG.

13. The method of Claim 12, wherein re-establishing the RLC entity comprises stopping and resetting a timer associated with the RLC entity.

14. The method of Claim 13, wherein the timer is stopped and reset without initiating any action associated with the timer.

15. The method of any of Claims 12 to 14, wherein re-establishing the RLC entity comprises discarding RLC service data units, SDUs, SDU segments, and/or protocol data units, PDUs, of the RLC entity.

16. The method of any of Claims 12 to 15, wherein re-establishing the RLC entity comprises resetting state variables associated with the RLC entity to initial values.

17. The method of any previous Claim, further comprising:

47 receiving a packet data convergence protocol, PDCP, protocol data unit, PDU, after deactivation of the SCG; and submitting the PDCP PDU to an RLC entity that is not associated with the deactivated SCG.

18. The method of any previous Claim, further comprising: indicating to a medium access control, MAC, entity associated with the deactivated SCG that a PDCP volume associated with the deactivated SCG is zero.

19. A user equipment, comprising: processing circuitry configured to perform any of the steps of any of Claims 1 to 18; and power supply circuitry configured to supply power to the processing circuitry.

20. A user equipment (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 Claims 1 to 18; 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.

21. A computer program comprising program code to be executed by processing circuitry (303, 1902, 2212) of a communication device (600, 1812A, 1812B, 1812C, 1812D, 1900, 2204, 2208 A, 2208B, 2306), whereby execution of the program code causes the communication device to perform operations according to any of Claims 1 to 18.

22. A computer program product comprising a non-transitory storage medium including program code to be executed by processing circuitry (603, 1902, 2212) of a communication device (600, 1812A, 1812B, 1812C, 1812D, 1900, 2204, 2208 A, 2208B, 2306), whereby execution of the program code causes the communication device to perform operations according to any of Claims 1 to 18.

48