Method and system for enhanced reliability and throughput of end-to-end traffic over cellular relay devices

Abstract

This invention relates to enhanced reliability and throughput when using relay devices such as cellular relay devices such as sidelink relay communication in the cellular network, or other relay devices such as an access device or satellite.

Description

[0001] METHOD AND SYSTEM FOR ENHANCED RELIABILITY AND THROUGHPUT OF END-TO-

[0002] END TRAFFIC OVER CELLULAR RELAY DEVICES

[0003] FIELD OF THE INVENTION

[0004] This invention relates to a communication device, base station device and method of end- to-end packet duplication and / or data split / aggregation for enhanced reliability and throughput when using relay devices such as cellular relay devices such as sidelink relay communication in a cellular network, or other relay devices such as an access device or satellite.

[0005] BACKGROUND

[0006] In the 3GPP specifications 23.304 and 24.501 for 5G networks, so-called proximity service (ProSe) functions are defined to enable - amongst others - connectivity for cellular communication devices (e.g., UEs) that are temporarily not in coverage of an access device (gNB). This particular function is called ProSe UE-to-Network relay, or Relay UE. The Relay UE is a communication device that helps another UE to communicate to the gNB (i.e., access device) by relaying application and network data traffic in two directions between the other UE and the gNB. The local communication between the Relay UE and the other UE is called D2D communication or sidelink communication or PC5 communication. The abbreviation “PC5” designates an interface for sidelink communication as defined by ProSe. Furthermore, the abbreviation “UL” is used for the uplink direction from the communication device (e.g., UE) to the access device (e.g., gNB), the abbreviation “DL” for the downlink direction from the access device (e.g., gNB) to the communication device (e.g., UE), and the abbreviation “SL” for sidelink communication between two or more communication devices (e.g., UEs). Once the relaying relation is established, a UE can be connected via the Relay UE and act in a role of “Remote UE”. This situation means that the Remote UE has an indirect network connection to the CN as opposed to a direct network connection that is the normal case (cf. 3GPP specification TS 22.261 vl6.10.0).

[0007] Furthermore, 3GPP specifications TR 23.733 vl5.1.0 and TR 36.746 vl5.1.1 provide studies on architectural enhancements e.g. to enable an loT device (in a role of Remote UE) to operate on very low power by using a Relay UE to connect to the wider network. Because the Relay UE is physically very close, it can be reached using very low power transmissions. This work also includes security, speed and stability improvements to ProSe. These extensions of ProSe are called enhanced ProSe (“eProSe”). One proposed improvement in eProSe is an enhanced relaying architecture that operates in the second protocol layer (i.e., L2) intended to offer end-to-end Internet Protocol (IP) packet and Packet Data Convergence Protocol (PDCP) packet transmissions to remote communication devices for application and / or user data. A benefit of this architecture is that the remote communication devices become directly visible as a registered entity in the CN, which is relevant for monitoring and billing purposes and for improved control by the access device over the communication device.

[0008] There are still some challenges and limitations in the current 3GPP sidelink relay solutions, especially for the multi-path relaying scenario. For example, the current solutions do not address how to efficiently split or aggregate data packets at the source UE, the relay UE, and the base station to optimize the end-to-end performance. Moreover, the current solutions do not consider how to handle packet duplication or retransmission in the multi-path relaying scenario, which may cause unnecessary overhead or interference. Furthermore, the current solutions do not provide a flexible and scalable framework to support different types of relay devices, such as cellular relay devices, access devices, or satellites, which may have different capabilities and requirements. Therefore, there is a need for an improved method and system for end-to-end packet duplication and aggregation data split / aggregation in the multipath relaying scenario, as well as a general and extensible mechanism to support various relay devices and technologies.

[0009] In Release 17 (R17), 3GPP standardized sidelink relay function for 5G NR, see RP- 212819, which supports L2 UE-to-Network (U2N) relay for a remote UE (User Equipment) out-of-coverage of the base station to connect to the cellular network via a relay UE like a regular in-network coverage UE, or for a remote UE at the edge of the base station with a poor connection to connect to the cellular network via a relay UE which has a better connection to the base station so that the connection of the remote UE to the base station can be improved. The major benefit of R17 sidelink relay is for network coverage extension and power efficiency improvement for UE out-of-coverage or at the edge of a cell.

[0010] In R18, 3GPP is further enhancing sidelink relay function, see RP-223501, which supports multi-path relaying for a remote UE in the coverage of the base station to connect to the network via direct path (Uu) and indirect path (U2N relay) simultaneously to improve reliability and robustness as well as throughput. In addition, UE-to-UE (U2U) relay which was studied in R17 is also standardized for sidelink coverage extension.

[0011] In the use case of ultra-reliability and low latency communications (URLLC) with sidelink relay, remote UEs, such as industrial Internet of Things (loT) devices, XR immersive communication devices, haptic communication devices, need to have extra reliability and very low latency to transmit the data to the base station (in the case of U2N relay), or to the target remote UE (in the case of U2U relay), via relay UE(s).

[0012] In another use case of high data rate video transmission with sidelink relay, remote UE, e.g., extended reality(XR) immersive communication device (i.e., for use in combinations of real and virtual environments using computer technology, including Augmented Reality (AR), Virtual Reality (VR), and Mixed Reality (MR)), Vehicle-to-Everything (V2X) device (i.e., for communication between a vehicle and any entity that may affect, or may be affected by, the vehicle) for high data rate local sensor data sharing, needs to transmit large amount of data to the base station in a very short period of time (in the case of U2N relay), or to the target remote UE (in the case of U2U relay), via relay UE(s).

[0013] In another use case, two UEs may be connected through one or more satellite links that enable direct communication between both UEs. In this use case, it is beneficial to ensure enhanced reliability and throughput.

[0014] If a remote UE is in the coverage of the cell / base station, R18 sidelink relay multi-path relaying may partly solve the above two problems. Because R18 sidelink relay multi-path relaying can be modelled similar to dual connectivity (DC), which allows remote UE to have two simultaneous connections with the cell / base station, i.e. direct path and indirect path. Ongoing standardization work in 3 GPP RAN2 has agreed on the following design principles:

[0015] Duplicated signaling radio bearers (SRBs) can be configured on both paths for the reliability of control plane signaling.

[0016] For data radio bearers (DRBs), either duplicated DRBs can be configured on both paths for reliability and robustness of user plane data, or split bearers can be configured to aggregate user plane data over two paths.

[0017] However, the remote UE needs to be in the direct coverage of the cell / base station in order to use sidelink relay multi-path relaying to improve reliability, robustness and / or throughput. For remote UEs out-of-coverage of the cell / base station in U2N relay, and remote UEs in U2U relay, there is no technology to allow the enhancement of end-to-end reliability, robustness, and low latency for the URLLC communications between remote UE and base station in U2N relay, or between source remote UE and target remote UE in U2U relay. Additionally, there is no technology to allow the end-to-end user traffic split and aggregation for high throughput eMBB (enhanced Mobile Broad Band) communications between remote UE and base station in U2N relay, or between source remote UE and target remote UE in U2U relay.

[0018] SUMMARY OF THE INVENTION

[0019] It is the object of this invention to provide a method and system for enhanced reliability and throughput of end-to-end traffic over cellular relay devices, e.g., end-to-end packet duplication and data split / aggregation in 4G, 5G, and future 6G cellular network supporting relays, such as sidelink or satellite relays between the source node and the target node over one or multiple relay nodes in the transmission path in order to optimize the end-to-end Quality of Service (QoS, such as reliability, robustness, latency, jitter, data rate, throughput, etc.) of the data traffic.

[0020] It is clear from the description of the problem above, that there is no end-to-end packet duplication or data split / aggregation scheme to duplicate or split the data stream of the packets or (IP) traffic between the source node and the target node in a transmission path of one or multiple hops. It is an object of the invention to overcome the end-to-end packet duplication and data split / aggregation problem, so that the packets of a data stream can be transmitted on multiple paths over every hop of a transmission path between the source node and the target node in a wireless network with improved reliability.

[0021] This object is solved by a first communication device as claimed in claim 1, a base station device as claimed in claim 6, a method as claimed in claim 8, and a computer program product as claimed in claim 9.

[0022] According to a first aspect, the invention relates to a first communication device for a wireless network, wherein the device supports end-to-end packet duplication and / or data split / aggregation over multiple hops, the first communication device being adapted to: establish one or more communication paths between the first and a second communication device; and receive configuration information from another communication device in the wireless network, wherein the configuration information comprises at least one parameter about the end-to-end packet duplication and / or the data split / aggregation over the one or more communication paths between the first communication device and the second communication device, and over one or more communication paths between the first communication device and at least one third communication device and / or between the at least one third communication device and the second communication; and perform at least one of the following based on the configuration information: establish one or more communication paths between the first communication device and the at least one third communication device based on the configuration information; or transmit configuration information to the second communication device comprising at least one parameter about the end-to-end packet duplication and / or the data split / aggregation over the one or more communication paths between the at least one third communication device and the second communication device; or transmit / receive data over the one or more communication paths between the first communication device and the at least one third communication device and / or between the at least one third communication device and the second communication device, by duplicating and / or splitting the data on one or more communication paths between the first communication device and the at least one third communication device and / or between the at least one third communication device and the second communication device depending on the configuration information.

[0023] In an alternative embodiment of the first communication device, the one or more communication paths between the first communication device and the second communication device may be one or more direct wireless connections or Radio Link Control (RLC) channels between the first communication device and the second communication device and / or one or more indirect wireless connections or relayed RLC channels between the first communication device and the second communication device via at the least one third communication device.

[0024] In an alternative embodiment of the first communication device, the second communication device may not be a destination endpoint of transmitted duplicated / split data and may not be an originating source of received duplicated / split data.

[0025] In an alternative embodiment of the first communication device, the at least one parameter about the end-to-end packet duplication over the one or more communication paths may comprise a QoS policy and / or a duplication threshold.

[0026] In an alternative embodiment of the first communication device, the at least one parameter about the data split / aggregation over the one or more communication paths may comprise a QoS policy and / or a data split threshold.

[0027] In a second aspect the present invention relates to a base station device in a wireless network, wherein the base station device supports end-to-end packet duplication and / or data split / aggregation over a wireless link to one more communication devices, the base station device being adapted to: connect to a first communication device directly if the base station device has a direct communication path with the first communication device; and connect to the first communication device indirectly if the base station device has an indirect communication path with the first communication device via one or more second communication devices; and establish one or more communication paths between the first communication device and the base station device; and configure the first communication device and the one or more second communication devices with at least one parameter about the end-to-end packet duplication and / or the data split / aggregation over the one or more communication paths between the first communication device and the base station device, and / or between the first communication device or the base station device and one or more second communication devices.

[0028] In an alternative embodiment of the second aspect, the base station device may further be adapted to perform at least one of the following based on the configuration information: establish one or more communication paths between the first communication device and the one or more second communication devices based on the configuration information; or transmit / receive data over the one or more communication paths between the first communication device, the base station device and the one or more second communication devices, by duplicating and / or splitting the data on one or more communication paths between the first communication device, the base station device and the one or more second communication devices depending on the configuration information. In a third aspect the present invention relates to a method of end-to-end packet duplication and / or data split / aggregation in a wireless network, the method comprising: establishing one or more communication paths between a first communication device and a second communication device; receiving configuration information from another communication device in the wireless network, wherein the configuration information comprises at least one parameter about the end-to-end packet duplication and / or the data split / aggregation over the one or more communication paths between the first communication device and the second communication device, and over one or more communication paths between the first communication device and at least one third communication device and / or between the at least one third communication device and the second communication device; and performing at least one of the following based on the configuration information: establishing one or more communication paths between the first communication device and the at least one third communication device based on the configuration information; or transmitting configuration information to the second communication device comprising at least one parameter about the end-to-end packet duplication and / or the data split / aggregation over the one or more communication paths between the at least one third communication device and the second communication device; or transmitting / receiving data over the one or more communication paths between the first communication device and the at least one third communication device and / or between the at least one third communication device and the second communication device, by duplicating and / or splitting the data on one or more communication paths between the first communication device and the at least one third communication device and / or between the at least one third communication device and the second communication device depending on the configuration information.

[0029] In a fourth aspect, the present invention relates to a computer program product comprising code means for producing the steps of the method of the third aspect when run on a computer device.

[0030] It shall be understood that a preferred embodiment of the invention can also be any combination of the dependent claims or above embodiments with the respective independent claim.

[0031] These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.

[0032] BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Fig. 1 schematically shows a side link relay UE-to-Network relay.

[0034] Fig. 2 schematically shows a 3GPP 5G NR R18 sidelink relay UE-to-Network relay multi-path relaying.

[0035] Fig. 3 schematically shows a 3GPP 5G NR R18 sidelink relay UE-to-UE relay. Fig. 4 schematically shows a 3GPP 5G NR R15 / R16 PDCP duplication with carrier aggregation on the Uu interface.

[0036] Fig. 5 schematically shows a 3GPP 5G NR R15 / R16 PDCP duplication with dual connectivity on the Uu interface.

[0037] Fig. 6 schematically shows a 3GPP 5G NR R15 / R16 PDCP duplication with dual connectivity and carrier aggregation on the Uu interface.

[0038] Fig. 7A schematically shows an end-to-end packet duplication scheme for a sidelink relay U2N relay, according to a first embodiment.

[0039] Fig. 7B schematically shows an end-to-end data split and aggregation scheme for a sidelink relay U2N relay, according to a second embodiment.

[0040] Fig. 8 A schematically shows an end-to-end packet duplication scheme for a sidelink relay U2U relay, according to a third embodiment.

[0041] Fig. 8B schematically shows an end-to-end data split / aggregation scheme for the sidelink relay U2U relay, according to a fourth embodiment.

[0042] Fig. 9 schematically shows QoS flows and radio bearer mappings during the end-to-end packet duplication and / or data split / aggregation scheme for the sidelink relay U2N relay of the first and / or second embodiment.

[0043] Fig. 10 schematically shows a protocol stack for the end-to-end packet duplication and / or data split / aggregation for the sidelink relay U2N relay, according to the first and / or second embodiment.

[0044] Fig. 11 schematically shows QoS flows and radio bearers mappings during the end-to-end packet duplication and / or data split / aggregation scheme for the sidelink relay U2U relay, according to the third and / or fourth embodiment.

[0045] Fig. 12 schematically shows a protocol stack for the end-to-end packet duplication and / or data split / aggregation for the sidelink relay U2U relay, according to the third and / or fourth embodiment.

[0046] Fig. 13 schematically shows an end-to-end packet duplication and / or data split / aggregation scheme for a sidelink relay multi-hop relaying U2N relay, according to a fifth embodiment.

[0047] Fig. 14 schematically shows an an end-to-end packet duplication and / or data split / aggregation scheme for a sidelink relay multi-hop relaying U2U relay, according to a sixth embodiment.

[0048] Fig. 15 schematically shows an end-to-end packet duplication and / or data split / aggregation channel between a source node and a target node, according to a seventh embodiment.

[0049] Fig. 16 schematically shows a deployment scenario of embodiments with two relay devices,

[0050] Fig. 17 schematically shows a protocol stack for traffic splitting / duplication.

[0051] DESCRIPTION OF EMBODIMENTS Embodiments of the present invention are described below based on a (e.g., 3GPP-based) cellular network environment.

[0052] Throughout the present disclosure, the abbreviation “gNB” (5G terminology) is intended to mean access device such as a cellular base station or a Wi-Fi access point. The gNB is part of the radio access network (RAN), which provides an interface to functions in the core network (CN). The RAN is part of a wireless communication network. It implements a radio access technology (RAT). Conceptually, it resides between a communication device such as a mobile phone, a computer, or any remotely controlled machine and provides connection with its CN. The CN is the communication network’s core part, which offers numerous services to customers who are interconnected via the RAN. More specifically, it directs communication streams over the communication network and possibly other networks. For example in case of a 5G cellular core network, an access and mobility management function (AMF) may terminate the control plane of different access networks onto the 5G CN (5GC) and control which UEs can access the 5GC to exchange traffic. It may also manage the mobility of UEs when they roam from one gNB to another for session / service continuity, whenever possible. Additionally, an Information Element (IE) designates (a group of) information which may be included within a signaling message or data flow which is sent across an interface (examples may include QoS (Quality of Service) definitions, setup parameters, user identifiers etc.). Furthermore, the abbreviation “UPF” shall designate a user plane function the is configured and responsible for connecting actual data coming over the RAN to the Internet. Further, a gateway mobile location center (GMLC) is used for active mobile positioning, meaning that it triggers specific activities on the network to retrieve a subscriber's location in real-time. For improved positioning precision, a GMLC can connect with additional precise location components in the network. The GMLC may contain functionality required to support LCS (LoCation Services). In one PLMN (Public Land Mobile Network), there may be more than one GMLC. The GMLC is the first node an external LCS client accesses in the network.

[0053] The medium access control (MAC) layer (as defined in 3GPP TS 38.321) is one of two sublayers that make up the data link layer. It plays a crucial role in managing radio resources and ensuring efficient communication within 5G networks. It serves to move data from a network interface card of a network to a shared channel. The MAC layer along with data link control is responsible for the complete physical addressing of the data link layer.

[0054] CARRIER AGGREGATION (CA)

[0055] Carrier aggregation is a technology to facilitate efficient use of fragmented spectra, where multiple component carriers are aggregated and jointly used for transmission to / from single device.

[0056] Carrier aggregation was firstly introduced in RIO of 4G LTE, and up to five component carriers (CCs), possibly each of different bandwidth, can be aggregated, allowing for transmission bandwidths up to 100 MHz. A different number of component carriers can be aggregated for the downlink and uplink. CCs do not have to be contiguous in the frequency and allow adjacent (intra-band contiguous) or non-adjacent (intra-band non-contiguous) CCs in the same frequency band, and CCs in different frequency bands (inter-band). R11 provided additional flexibility for aggregation of TDD (Time Division Duplexing) carriers with different downlink-uplink allocations. R12 defined aggregations between FDD (Frequency Division Duplexing) and TDD carriers. R13 increased the number of component carriers possible to aggregate from 5 to 32, resulting in a maximum bandwidth of 640 MHz.

[0057] 5G New Radio (NR) RAT supports carrier aggregation from the first release, R15. Up to 16 carriers, possibly of different bandwidths and different duplex schemes, can be aggregated allowing for overall transmission bandwidth of up to 16*400 MHz = 6.4 GHz.

[0058] In the specifications, carrier aggregation is described using the term cell, that is, a carrier aggregation capable device can receive and transmit from / to multiple cells. One of these cells is referred to as the primary cell (PCell). PCell is the cell which the device initially finds and connects to, after which one or more secondary cells (SCells) can be configured once the device is in connected mode. SCells can be rapidly activated or deactivated to meet the variations in traffic pattern.

[0059] Carrier aggregation may imply a very tight coordination with all the cells belonging to the same gNB. Scheduling decisions are taken jointly for all the cells the device is connected to by one joint scheduler in one MAC entity. Carrier aggregation supports self-scheduling and cross-carrier scheduling.

[0060] SIDELINK CARRIER AGGREGATION

[0061] 4G LTE defined side link multi -carrier operation / carrier aggregation in R15. When operating in CA, a given sidelink MAC protocol data unit (PDU) is transmitted, and if necessary re-transmitted, on a single sidelink carrier, and multiple MAC PDUs can be transmitted in parallel on different carriers. This provides a throughput gain in a similar way as for Uu CA, see TR 37.985 V17.1.1. LTE sidelink CA supports resource allocation modes 3 and 4.

[0062] In 5G NR R18, 3GPP is further enhancing sidelink to support carrier aggregation, which is expected to support similar LTE sidelink CA features for NR, see RP-230077.

[0063] DUAL CONNECTIVITY (DC)

[0064] Dual connectivity is a feature firstly introduced in 4G LTE R12 to allow a UE simultaneously connected to two cells at different sites / base stations and transmit / receive packets via both base stations. Either duplicated bearers (SRBs, DRBs) or split bearers can be configured in two cell groups (i.e., MCG and SCG) to enhance reliability or throughput respectively.

[0065] DC allows for a much looser coordination between the cells. The cells can belong to different base stations, and they may even belong to different radio access technologies as is the case for NR-LTE dual connectivity in case of non-standard alone (NSA) operation, which was defined for early introduction of NR in R15 where mobility and initial access related control plane functionality is through LTE and user plane data transmission is through NR.

[0066] CA and DC can also be combined. Terms as Master Cell Group (MCG) and Secondary Cell Group (SCG) are defined for DC, and within each of the cell groups, CA can be used. A UE supporting DC has different MAC entities for MCG and SCG respectively.

[0067] SIDELINK RELAY

[0068] Sidelink relay is introduced to support 5G ProSe UE-to-Network Relay (U2N Relay) function to provide connectivity to the network for U2N remote UE(s) either in the coverage or out of the coverage of the network in R17, see WID RP-212819. A single unicast PC5 link is established between one U2N relay UE and one U2N remote UE.

[0069] Sidelink relay in R18 is further enhanced to support multi-path relaying for a U2N remote UE in the coverage of the base station to establish simultaneously direct path and indirect path via a U2N relay UE to the same base station. Multi-path relaying can be modeled similar to DC in the layer 2 (which includes MAC, Radio Link Control (RLC) and Packet Data Conversion Protocol (PDCP)) except the multi-path UE is assumed to have single MAC entity when using resource allocation mode 1 for resource scheduling on the PC5 sidelink of the indirect path in the intra-DU case.

[0070] It is noted that throughout the present disclosure only those blocks, components and / or devices that are relevant for the proposed embodiments are shown in the accompanying drawings. Other blocks have been omitted for reasons of brevity. Furthermore, blocks designated by the same reference numbers are intended to have the same or at least a similar function, so that their function is not described again later.

[0071] Fig. 1 depicts a 3GPP 5G NR R17 sidelink relay U2N relay function, where a remote UE 10 out-of-coverage, in-coverage, partial-coverage may connect to the base station 20 via a relay UE 12 indirectly. The end-to-end SRBs and DRBs between remote UE 10 and the base station 20 are transmitted over two hops, namely a PC5 hop between remote UE and relay UE 12 and Uu hop between relay UE 12 and the base station 20.

[0072] Fig. 2 depicts a 3GPP 5G NR R18 sidelink relay U2N relay multi-path relaying function, where a remote UE 10 in-coverage connects to the base station 20 via a direct path (DP) and an indirect path (IP) simultaneously. The direct path is on the Uu interface between remote UE 10 and the base station 20, while the indirect path is the R17 sidelink relay U2N relay path via relay UE 12.

[0073] Fig. 3 depicts a 3GPP 5G NR R18 sidelink relay U2U relay function, where source remote UE 10-S connects to the target remote UE 10-T indirectly via a relay UE 12 when direct link between source remote UE 10-S and target remote UE 10-T is poor or not possible at all.

[0074] PDCP DUPLICATION 5G NR PDCP duplication was defined in R15 and enhanced in R16 to support URLLC communication for Industrial loT (IIoT) UEs. When duplication is configured for a radio bearer by RRC, at least one secondary RLC entity is added to the radio bearer to handle the duplicated PDCP PDUs, see TS 38.300 V17.4.0, clause 16.1.3, Fig. 16.1.3-1. All RLC entities have the same RLC mode. Duplication at PDCP therefore consists of submitting the same PDCP PDUs multiple times: once to each activated RLC entity for the radio bearer. With multiple independent transmission paths, packet duplication therefore increases reliability and reduces latency.

[0075] When duplication is configured for an SRB the state is always active and cannot be dynamically controlled.

[0076] When configuring duplication for a DRB, RRC also sets the state of PDCP duplication (either activated or deactivated) at the time of (re-)configuration. After the configuration, the PDCP duplication state can then be dynamically controlled by means of a MAC control element (CE).

[0077] When duplication is activated, the original PDCP PDU and the corresponding dupli- cate(s) shall not be transmitted on the same carrier. The logical channels of a radio bearer configured with duplication can either belong to the same MAC entity (referred to as CA duplication) or to different ones (referred to as DC duplication). CA duplication can also be configured in either or both of the MAC entities together with DC duplication when duplication over more than two RLC entities is configured for the radio bearer. In CA duplication, logical channel mapping restrictions are used in a MAC entity to ensure that the different logical channels of a radio bearer in the MAC entity are not sent on the same carrier. When CA duplication is configured for an SRB, one of the logical channels associated to the SRB is mapped to SpCell.

[0078] Fig. 4 depicts a 3GPP 5G NR R15 PDCP duplication scheme with carrier aggregation, where the same PDCP data packet may be transmitted by a PDCP entity 30 over multiple RLC channels with different sequence numbers (SN=1,2,3 . . . ) via a primary RLC entity (P-RLC) 42 and a plurality of secondary RLC entities (S-RLC) 44 to a MAC entity 50, wherein each RLC channel / logical channel can map to different component carriers (CC1 to CCn) at the transmitter side, and at the receiver side, the PDCP data packet may be received over the multiple RLC channels mapped to the different component carriers and the duplicated PDCP data packet can be dropped by the receiver and only one copy of a PDCP service data unit (SDU) may be sent to the upper layer.

[0079] Fig. 5 depicts a 3GPP 5G NR R15 PDCP duplication scheme with dual connectivity, which is different from carrier aggregation based PDCP duplication in the sense that two cell groups are involved in the dual connectivity and Xn application protocol (XnAP) messages are defined to exchange via an Xn interface (Xn-IF) the PDCP data packet between an MCG and an SCG. At the transmitter side, a PDCP entity 30 in the MCG may use an XnAP message to send a copy of the PDCP data packet to the SCG, and both MCG and SCG may have its own RLC entity (a primary RLC entity 42 at the MCG and a secondary RLC entity 44 at the SCG) to transmit the PDCP data packet using own resources; at the receiver side, the same copies of the PDCP data packet may be received at the MCG and the SCG respectively, the SCG may forward the received PDCP data packet to the MCG using an XnAP message, then the MCG may detect the PDCP data duplicates and discard the duplicates, and may send only one copy of an PDCP SDU to the upper layer (i.e., MAC entity 50) using respective carriers Cl, C2 in different cell groups, i.e. MCG and SCG respectively.

[0080] Fig. 6 depicts a PDCP duplication scheme where both carrier aggregation and dual connectivity are applied. In either MCG or SCG, a PDCP data packet may be duplicated over multiple component carriers CCmi to CCm_n or CCS_i to CCS_n, respectively, while between the MCG and the SCG, the PDCP data packet may be duplicates in each cell group.

[0081] SPLIT BEARER

[0082] In dual connectivity (DC), UEs can be configured to utilize radio resources from two different gNBs, i.e., a Master gNB (MgNB), which maintains the control plane, and a Secondary gNB (SgNB).

[0083] A split bearer is a bearer whose radio protocols are located in both the MgNB and the SgNB to use both MgNB and SgNB resources.

[0084] A non-split bearer is a bearer whose radio protocols are located in either the MgNB or the SgNB to use MgNB or SgNB resource, respectively.

[0085] According to TS 38.323 V17.5.0, each radio bearer (RB) (except for SRBO for Uu interface) is associated with one PDCP entity. Each PDCP entity is associated with one, two, three, four, six, or eight RLC entities depending on the RB characteristic (e.g., uni-directional / bi-directional or split / non- split) or RLC mode:

[0086] - For split bearers, each PDCP entity is associated with two un-acknowledged mode (UM) RLC entities (for same direction), four UM RLC entities (two for each direction), or two acknowledged mode (AM) RLC entities;

[0087] - For RBs configured with PDCP duplication, each PDCP entity is associated with N UM RLC entities (for same direction), 2 * N UM RLC entities (N for each direction), or N AM RLC entities, where 2 <= N <= 4;

[0088] - For DAPS bearers, each PDCP entity is associated with two UM RLC entities (for same direction, one for source and one for target cell), four UM RLC entities (two for each direction on source cell and target cell), or two AM RLC entities (one for source cell and one for target cell);

[0089] - For UM Multicast / Broadcast Service (MBS) RBs (MRBs), each PDCP entity is associated with one UM RLC entity (for MBS traffic channel (MTCH) or for downlink Dedicated Traffic Channel (DTCH)), two UM RLC entities (one for MTCH and one for downlink DTCH, or one for downlink DTCH and one for uplink DTCH), or three UM RLC entities (one for MTCH, one for downlink DTCH, and one for uplink DTCH); - For AM MRBs, each PDCP entity is associated with one AM RLC entity (for downlink DTCH and uplink DTCH), or one UM RLC entity (for MTCH) and one AM RLC entity (for downlink DTCH and uplink DTCH);

[0090] - Otherwise, each PDCP entity is associated with one UM RLC entity, two UM RLC entities (one for each direction), or one AM RLC entity.

[0091] SIDELINK PDCP DUPLICATION

[0092] 4G LTE supported sidelink carrier aggregation and sidelink PDCP duplication in R15, where the same PDCP packet is transmitted in parallel on multiple sidelink carriers, to increase reliability. 4G LTE R15 supports sidelink PDCP duplication over two different sidelink carriers, see TS 36.323 V17.2.0 (2022-12), clause 5.1.3 and clause 5.1.4 on the details.

[0093] In 5G NR R18, 3GPP is further enhancing sidelink to support carrier aggregation, which is expected to support similar LTE sidelink PDCP duplication feature for NR, see RP-230077.

[0094] PACKET DUPLICATION / AGGREGATION FOR SIDELINK RELAY

[0095] As mentioned above, for sidelink relay (both U2N relay and U2U relay), although there are existing mechanisms such as carrier aggregation, dual connectivity and PDCP duplication / aggregation for the wireless link on each hop of the transmission path, such as in U2N relay, sidelink CA with PDCP duplication / aggregation on PC5 link, and Uu CA with PDCP duplication / aggregation on Uu link, and in U2U relay, sidelink CA with PDCP duplication / aggregation on the first PC5 link between source remote UE and relay UE, and the second PC5 link between relay UE and target remote UE, there is no packet duplication / aggregation scheme covering all the wireless links on all hops of the transmission path end-to- end between the source node and the target node.

[0096] In multipath communication, a UE capable of Access Traffic Steering Switching & Splitting (ATSSS-capable UE), that can steer, switch and split the Multi-Access PDU Session traffic across 3GPP access and non-3GPP access, is called a "steering functionality" (TS 23.501). An ATSSS-capable UE may support one or more of the following types of steering functionalities: (1) High-layer steering functionalities, which operate above the IP layer and may be based on multi-path TCP or multi-path QUIC; (2) Low-layer steering functionalities, which operate below the IP layer. For instance, Fig. 5.32.6.2.2-1 of TS 23.501 describes the user plane protocol stack when the Multipath Quick User Datagram Protocol (UDP) Internet Connection (QUIC) functionality is applied between UE and UPF.

[0097] The above Fig. 2 to Fig. 6 schematically show respectively different multi-path schemes already known and / or supported in 3GPP 5G / NR. However, there is no end-to-end SRBs / DRBs packet duplication and / or data split / aggregation scheme existing over every hop of the transmission path between the source node and the target node. END-TO-END PACKET DUPLICATION

[0098] Fig. 7A schematically show an end-to-end packet duplication scheme between remote UE and the base station for L2 U2N sidelink relay, where two hops exist (i.e., PC5 and Uu) according to a first embodiment. On each hop, at least one packet duplication scheme may be used. For example, the PC5 hop between remote UE 10 and relay UE 12 may use the sidelink carrier aggregation (SL-C) to transmit the packet (e.g., PDCP data packet) over multiple relay RLC channels on different sidelink component carriers; the Uu hop between relay UE 12 and the base station 20 may use either carrier aggregation or dual connectivity or both to transmit the duplicated packet (e.g., PDCP data packet) over multiple relay RLC channels on different Uu component carriers or RLC channels in the cell groups or both. At the transmitter side, the user traffic may duplicate at the PDCP layer, the PDCP data packet may duplica- tively transmit on multiple relay RLC channels over every hop of the transmission path; at the receiver side, the PDCP entity at the receiver may detect / discard duplicates and only deliver one copy of the PDCP SDU to the upper layer.

[0099] Since each hop may have a different packet duplication scheme employed, and the number of relay RLC channels on every hop may be different from hop to hop, there is a need for each node in the transmission path to maintain a table to map the end-to-end SRBs / DRBs to the relay RLC channels on each hop of the transmission path.

[0100] In one embodiment, the source node may have an RLC bearer mapping table of multiple entries, where each entry may have the mapping information of one end-to-end SRB / DRB to the corresponding relay RLC channels for the first hop of the transmission path. Furthermore, the source node may have a parameter to determine whether packet duplication scheme may be applied to the multiple relay RLC channels or not.

[0101] SL-L2Remote UE-Config-rl 9 ::= SEQ UENCE { sl-SRAP-ConfigRemote-r!9 SL-SRAP-Config-rl9 OPTIONAL, —NeedM pdcp-Duplication BOOLEAN OPTIONAL — Need R sl-UEIdentityRemote-r!9 RNTI-Value OPTIONAL, — Cond FirstRRCReconfig

[0102] }

[0103] SL-SRAP-Config-rl 9 ::= SEQ UENCE { sl-LocalIdentity-r!9 INTEGER (0..255) OPTIONAL, - Need M sl-MappingToAddModList-r!9 SEQUENCE (SIZE (L.maxLC-ID)) OF SL- MappingToAddMod-rl9 OPTIONAL, - NeedN sl-MappingToReleaseList-rl9 SEQUENCE (SIZE (l..maxLC-ID)) OF SL-RemoteUE-RB- Identity-rl 7 OPTIONAL, - Need N

[0104] }

[0105] SL-MappingToAddMod-rl 9 ::= SEQ UENCE { sl-Remote UE-RB-Identity-rl 7 SL-Remote UE-RB-Identity-rl 7, sl-EgressRLC-Channel-r!9 SEQUENCE (SIZE (l..maxLC-ID)) OF SL-RelayRLC- ChannellD-rl 9 OPTIONAL, - Need N

[0106] }

[0107] SL-Remote UE-RB-Identity-rl 7 ::= CHOICE { srb-Identity-rl 7 INTEGER (0..3), drb-Identity-rl 7 DRB-Identity,

[0108] }

[0109] SL-RelayRLC-ChannelID-rl9 :: = INTEGER (L.maxLC-ID)

[0110] In the above Abstract Syntax Notation One (ASN. 1) information element (IE) definition, sl-SRAP-ConfigRemote may include the Sidelink Relay Adaptation Protocol (SRAP) configuration of the source node (Remote UE 10) as defined in TS 38.351. sl-Localldentity may indicate the local UE ID of the remote UE. pdcp-Duplication indicates whether PDCP duplication may be applied or not. sl-Re- moteUE-RB-Identity may indicate the end-to-end SRB / DRB identity of the data stream. sl-EgressRLC- Chcmnel may indicate a list of relay RLC channels for the corresponding end-to-end SRB / DRB on the first hop at the source node of the transmission path.

[0111] In a variant of the first embodiment, the relay node 12 may have an RLC bearer mapping table of multiple entries, where each entry may have the mapping information of one end-to-end SRB / DRB to the corresponding relay RLC channels for the two hops that the relay node bridges, at the relay node of the transmission path. Furthermore, the relay node 12 may have a parameter to determine whether packet duplication scheme may be applied to the multiple relay RLC channels or not on either hop of the relay node bridges.

[0112] SL-L2RelayUE-Config-rl9 : : = SEQUENCE { sl-SRAP-ConfigRelay-rl 9 SL-SRAP-Config-rl 9 OPTIONAL, -NeedM pdcp-DuplicationHopl BOOLEAN OPTIONAL — NeedR pdcp-DuplicationHop2 BOOLEAN OPTIONAL - NeedR

[0113] }

[0114] SL-SRAP-Config-rl 9 ::= SEQ UENCE { sl-LocalIdentity-r!9 INTEGER (0..255) OPTIONAL, - Need M sl-MappingToAddModList-r!9 SEQUENCE (SIZE (L.maxLC-ID)) OF SL-

[0115] MappingToAddMod-rl9 OPTIONAL, - NeedN sl-MappingToReleaseList-r!9 SEQUENCE (SIZE (L.maxLC-ID)) OF SL-RemoteUE-RB- Identity-rl 7 OPTIONAL, - Need N

[0116] SL-MappingToAddMod-rl 9 ::= SEQ UENCE { sl-Remote UE-RB-Identity-rl 7 SL-Remote UE-RB-Identity-rl 7, sl-EgressRLC-ChannelHopl-r!9 SEQUENCE (SIZE (L.maxLC-ID)) OF SL-RelayRLC-

[0117] ChannelID-rl9 OPTIONAL, - Cond L2RelayUE sl-EgressRLC-ChannelHop2-rl9 SEQUENCE (SIZE (L.maxLC-ID)) OF SL-RelayRLC-

[0118] ChannellD-rl 9 OPTIONAL, - Need N

[0119] }

[0120] SL-Remote UE-RB-Identity-rl 7 ::= CHOICE { srb-Identity-rl 7 INTEGER (0..3), drb-Identity-rl 7 DRB-Identity,

[0121] }

[0122] SL-RelayRLC-ChannelID-rl9 :: = INTEGER (L.maxLC-ID)

[0123] In the above ASN.l IE definition, sl-Localldentity may indicate the local UE ID of remote UE, as defined in the SRAP protocol TS 38.351. sl-RemoteUE-RB-Identity may indicate the end-to- end SRB / DRB identity of the data stream. pdcp-DuplicationHopl and pdcp-DuplicationHop2 indicate whether PDCP duplication may be applied or not on respective hop the relay node bridges. sl-EgressRLC- ChannelHopl and sl-EgressRLC-ChannelHop2 may indicate a list of relay RLC channels for the corresponding end-to-end SRB / DRB on respective hop the relay node bridges at the relay UE 12 of the transmission path.

[0124] In a variant of the first embodiment, the target node (RAN node such as gNB, gNB- DU / CU in the case of U2N relay, another remote UE in the case of U2U relay) may have an RLC bearer mapping table of multiple entries, where each entry may have the mapping information of one end-to-end SRB / DRB to the corresponding relay RLC channels for the last hop of the transmission path. Furthermore, the target node may have a parameter to determine whether packet duplication scheme may be applied to the multiple relay RLC channels or not.

[0125] SL-L2TargetNode-Config-rl 9 ::= SEQ UENCE { sl-SRAP-ConfigTarget-r!9 SL-SRAP-Config-rl9 OPTIONAE —NeedM pdcp-Duplication BOOLEAN OPTIONAL — Need R

[0126] SL-SRAP-Config-rl 9 ::= SEQ UENCE { sl-LocalIdentity-r!9 INTEGER (0..255) OPTIONAL, - Need M sl-MappingToAddModList-r!9 SEQUENCE (SIZE (L.maxLC-ID)) OF SL-

[0127] MappingToAddMod-rl9 OPTIONAL, - NeedN sl-MappingToReleaseList-r!9 SEQUENCE (SIZE (L.maxLC-ID)) OF SL-RemoteUE-RB- Identity-rl 7 OPTIONAL, - Need N

[0128] SL-MappingToAddMod-rl 9 ::= SEQ UENCE { sl-Remote UE-RB-Identity-rl 7 SL-Remote UE-RB-Identity-rl 7, sl-EgressRLC-Channel-r!9 SEQUENCE (SIZE (L.maxLC-ID)) OF SL-RelayRLC-

[0129] ChannellD-rl 9 OPTIONAL, - Need N

[0130] SL-Remote UE-RB-Identity-rl 7 :: = CHOICE { srb-Identity-rl 7 INTEGER (0..3), drb-Identity-rl 7 DRB-Identity,

[0131] }

[0132] SL-RelayRLC-ChannelID-rl9 :: = INTEGER (E.maxLC-ID)

[0133] In the above ASN.l IE definition, sl-SRAP-ConfigRemote may include the SRAP configuration of the target node (base station, gNB-DU / CU in L2 U2N Relay, target Remote UE in L2 U2U Relay) as defined in TS 38.351. sl-Localldentity may indicate the local UE ID of remote UE. sl-RemoteUE- RB-Identity may indicate the end-to-end SRB / DRB identity of the data stream. pdcp-Duplication indicates whether PDCP duplication may be applied or not. sl-EgressRLC-Channel may indicate a list of relay RLC channels for the corresponding end-to-end SRB / DRB on the last hop at the target node of the transmission path.

[0134] In a variant of the first embodiment, the relay RLC channel may be a PC5 Relay RLC channel mapped to a sidelink component carrier.

[0135] In a variant of the first embodiment, the relay RLC channel may be bi-directional.

[0136] In a variant of the first embodiment, the target node may be a base station, gNB-DU / CU. In a variant of the first embodiment, the target node may be another Remote UE.

[0137] In a variant of the first embodiment, the relay RLC channel may be a Uu Relay RLC channel mapped to a Uu component carrier of the MCG.

[0138] In a variant of the first embodiment, the relay RLC channel may be a Uu Relay RLC channel mapped to a Uu component carrier of the SCG.

[0139] In a variant of the first embodiment, the configuration information above may include the number of transmission paths (e.g., relay RLC channels) on each hop of the end-to-end transmission path.

[0140] In a variant of the first embodiment, the configuration information may have a default number of transmission paths (e.g., relay RLC channels) on each hop of the end-to-end transmission path either specified in the standards specification, or network pre-configuration / SIB / RRC signaling.

[0141] In a variant of the first embodiment, the gNB and / or gNB-DU / CU may configure the configuration information related to end-to-end packet duplication and / or data split / aggregation (or a subset thereof) to one or more (potential) nodes (e.g., source device, target device, intermediate / relay device) when such node is in the coverage of the base station.

[0142] In a variant of the first embodiment, the configuration information related to end-to-end packet duplication and / or data split / aggregation (or a subset thereof) may be preconfigured into a node (e.g., through a set of policies provided by the network or installed on the device). In a variant of the first embodiment, the configuration information related to end-to-end packet duplication and / or data split / aggregation (or a subset thereof) may be configured via RRC signaling, MAC Control Elements, and / or SIB broadcasting and / or on-demand SIB request.

[0143] In a variant of the first embodiment, the configuration information related to end-to-end packet duplication and / or data split / aggregation (or subset thereof) may be configured in a node by receiving the configuration information (or subset thereof) from another node in the network (e.g., another node that is part of the transmission path), for example by receiving a PC5-RRC or other message containing such configuration information over the sidelink from a node has a direct link with the node.

[0144] In a variant of the first embodiment, the gNB and / or gNB-DU / CU may not necessarily need to signal the configuration to itself, as it may be some information stored in the memory or storage of the device.

[0145] In the first embodiment, the user data may be duplicated according to the throughput and / or capacity of different relay RLC channels. A duplication threshold (e.g., minimum / maximum amount of data, data rate, capacity, delay,jitter, reliability, transmission / reception error rate, or amount of frames lost) may be configured / used to determine whether the user traffic may be duplicated on two and more RLC channels. The determination and / or applying the threshold may further include measuring the current performance (e.g., current data rate, signal strength, transmission / reception error rate, delay incurred, or amount of frames lost) for the various connections and / or RLC channels.

[0146] In another variant of the first embodiment, the user traffic may be duplicated according to the desired data rate or desired reliability or desired error rate or the delay budget configured by a QoS policy on the user traffic, where such QoS policy may be applied by the upper layer at an Service Data Adaption Protocol (SDAP) entity which is responsible for mapping between a QoS flow from the 5G CN and a DRB, as well as marking the QoS flow identifier (QFI) in uplink and downlink packets.

[0147] In another variant of the first embodiment, a node in the transmission path may apply the QoS policy to other nodes of the transmission path.

[0148] In a third embodiment, Fig. 8 A schematically shows an end-to-end packet duplication scheme between source remote UE 10-S and target remote UE 10-T for an L2 U2U sidelink relay 12, where two hops exist (i.e., PC5 and PC5). On each hop, at least one packet duplication scheme may be used. For example, the first PC5 hop between the source remote UE 10-S and the relay UE 12 may use the sidelink carrier aggregation to transmit the packet (e.g., PDCP data packet) over multiple RLC channels on different sidelink component carriers; similarly, the second PC5 hop between the relay UE 12 and the target remote UE 10-T may use sidelink carrier aggregation as well to transmit the packet (e.g., PDCP data packet) over multiple RLC channels on different sidelink component carriers. At the transmitter side, the user traffic may duplicate at the PDCP entity, the PDCP data packet may duplicatively transmit on multiple relay RLC channels over every hop of the transmission path; at the receiver side, the PDCP entity at the receiver may detect / discard duplicates and only deliver one copy of the PDCP SDU to the upper layer.

[0149] Since each hop may have different packet duplication scheme employed, and the number of alternative communication paths on every hop may be different from hop to hop, there may be a need for each node in the transmission path to maintain a table to map the end-to-end SRBs / DRBs to the relay RLC channels on each hop of the transmission path.

[0150] In the third embodiment, the source node (e.g., source remote UE 10-S) may have an RLC bearer mapping table of multiple entries, where each entry may have the mapping information of one end-to-end SRB / DRB to the corresponding relay RLC channels for the first hop of the transmission path, furthermore, the source node (e.g., source remote UE 10-S) may have a parameter to determine whether packet duplication scheme may be applied to the multiple relay RLC channels or not.

[0151] In a variant of the third embodiment, the relay node 12 may have an RLC bearer mapping table of multiple entries, where each entry may have the mapping information of one end-to-end SRB / DRB to the corresponding relay RLC channels for the two hops that the relay node bridges, at the relay node of the transmission path. Furthermore, the relay node 12 may have a parameter to determine whether packet duplication scheme may be applied to the multiple relay RLC channels or not on either hop of the relay node bridges.

[0152] In a variant of the third embodiment, the target node (e.g., target remote UE 10-T) may have an RLC bearer mapping table of multiple entries, where each entry may have the mapping information of one end-to-end SRB / DRB to the corresponding relay RLC channels for the last hop of the transmission path. Furthermore, the target node (e.g., target remote UE 10-T) may have a parameter to determine whether packet duplication scheme may be applied to the multiple relay RLC channels or not.

[0153] END-TO-END DATA SPLIT AND AGGREGATION

[0154] Fig. 7B depicts an end-to-end data split and aggregation scheme between the remote UE 10 and the base station 20 for L2 U2N sidelink relay, according to a second embodiment, where two hops exist (i.e., PC5 and Uu). On each hop, at least one data split and aggregation scheme may be used. For example, the PC5 hop between remote UE 10 and relay UE 12 may use the sidelink carrier aggregation to transmit the packet (e.g., PDCP data packet) over multiple relay RLC channels on different sidelink component carriers, and each relay RLC channel may transmit part of the packets according to the QoS policy configured on the end-to-end user traffic, such as minimum / maximum amount of data, data rate, capacity, delay, jitter, reliability, transmission / reception error rate, or amount of frames lost etc.; the Uu hop between relay UE 12 and the base station 20 may use either carrier aggregation or dual connectivity or both to transmit the split data packets (e.g., PDCP data packet) over multiple relay RLC channels mapped to different Uu component carriers or carriers in the cell groups or both. At the transmitter side, the user traffic may split at PDCP layer, PDCP data packet may transmit on multiple relay RLC channels at every hop of the transmission path; at the receiver side, the PDCP entity at the receiver may assemble the received PDCP data packet from multiple relay RLC channels in sequence and then deliver the in-order PDCP SDU to the upper layer.

[0155] In the second embodiment, the user traffic may be split according to the throughput and / or capacity of different relay RLC channels. A data split threshold (e.g., minimum / maximum amount of data, data rate, capacity, delay, jitter, reliability, transmission / reception error rate, or amount of frames lost) may be configured / used to determine whether the user traffic may be transmitted on one relay RLC channel or two and more relay RLC channels.

[0156] In the second embodiment, the user traffic may only be transmitted on one relay RLC channel if the amount of data to transmit is below a threshold.

[0157] In the second embodiment, the user traffic may transmit on more than one relay RLC channels if the amount of data to transmit is above the threshold.

[0158] In a variant of the second embodiment, the user traffic may be split according to the delay budget configured by the QoS policy on the user traffic. The high latency relay RLC channel may transmit a smaller portion of the user traffic while the low latency relay RCL channel may transmit a larger portion of the user traffic.

[0159] In a variant of the second embodiment, the user traffic may be split according to a round robin rule that each relay RLC channel may transmit the same amount of data.

[0160] In a variant of the second embodiment, the PDCP entity at the transmitter side may only randomly select one relay RLC channel to transmit PDCP data packet carrying the user traffic.

[0161] Since each hop may have different data split / aggregation scheme employed, and the number of relay RLC channels on every hop may be different from hop to hop, there may be a need for each node in the transmission path to maintain a table to map the end-to-end SRBs / DRBs to the relay RLC channels on each hop of the transmission path.

[0162] In the second embodiment, the source node may have an RLC bearer mapping table of multiple entries, where each entry may have the mapping information of one end-to-end SRB / DRB to the corresponding relay RLC channels for the first hop of the transmission path. Furthermore, the source node may have a threshold parameter to determine whether data split may be applied to multiple relay RLC channels or not.

[0163] SL-L2Remote UE-Config-rl 9 ::= SEQ UENCE { sl-SRAP-ConfigRemote-r!9 SL-SRAP-Config-rl9 OPTIONAL, —NeedM ul-DataSplitThreshold UL-DataSplitThreshold OPTIONAL, — Cond SplitBearer si- UEIdentityRemote-rl 9 RNTI-Value OPTIONAL, — Cond FirstRRCReconfig }

[0164] UL-DataSplitThre shold :: = ENUMERATED {

[0165] 5 bO, blOO, b200, b400, b800, b!600, b3200, b6400, b!2800, b25600, b51200, b 102400, b 204800, b409600, b819200, bl 228800, bl 638400, b2457600, b 3276800, b4096000, b4915200, b 5734400, b6553600, infinity, spare8, spare7, spare6, spare5, spare4, spare3, spare2, spare 1} 10

[0166] SL-SRAP-Config-rl 9 ::= SEQ UENCE { sl-Local!dentity-rl9 INTEGER (0..255) OPTIONAL, - Need M sl-MappingToAddModList-rl9 SEQUENCE (SIZE (L.maxLC-ID)) OF SLA MappingToAddMod-rl9 OPTIONAL, — NeedN sl-MappingToReleaseList-rl9 SEQUENCE (SIZE (L.maxLC-ID)) OF SL-RemoteUE-RB-

[0167] Identity-rl 7 OPTIONAL, - Need N

[0168] }

[0169] 20

[0170] SL-MappingToAddMod-rl 9 ::= SEQ UENCE { sl-Remote UE-RB-Identity-rl 7 SL-Remote UE-RB-Identity-rl 7, sl-EgressRLC-Channel-rl9 SEQUENCE (SIZE (L.maxLC-ID)) OF SL-RelayRLC- ChannellD-rl 9 OPTIONAL, - Need N

[0171] 25

[0172] }

[0173] SL-Remote UE-RB-Identity-rl 7 ::= CHOICE { srb-Identity-rl 7 INTEGER (0..3), 30 drb-Identity-rl 7 DRB-Identity,

[0174] }

[0175] SL-RelayRLC-ChannelID-rl9 :: = INTEGER (L.maxLC-ID) In the above ASN.l IE definition, sl-SRAP-ConfigRemote may include the SRAP configuration of the source node (Remote UE) as defined in TS 38.351. sl-Localldentity may indicate the local UE ID of remote UE. sl-RemoteUE-RB-Identity may indicate the end-to-end SRB / DRB identity of the data stream. sl-EgressRLC-Channel may indicate a list of relay RLC channels for the corresponding end- to-end SRB / DRB on the first hop at the source node of the transmission path. ul-DataSplitThreashold may indicate the threshold used to determine whether data split may be applied to split the user traffic over multiple relay RLC channels or not.

[0176] In a variant of the second embodiment, the relay node 12 may have an RLC bearer mapping table of multiple entries, where each entry may have the mapping information of one end-to-end SRB / DRB to the corresponding relay RLC channels for the two adjacent hops, which the relay node 12 is bridged / interconnected, at the relay node 12 of the transmission path. Furthermore, the relay node 12 may have a threshold parameter for each hop of the two hops which relay node bridges to determine whether data split may be applied to multiple relay RLC channels or not.

[0177] SL-L2RelayUE-Config-rl9 : : = SEQUENCE { sl-SRAP-ConfigRelay-rl 9 SL-SRAP-Config-rl 9 OPTIONAL, -NeedM ul-DataSplitThresholdHopl UL-DataSplitThreshold OPTIONAL, — Cond Split-

[0178] Bearer ul-DataSplitThresholdHop2 UL-DataSplitThreshold OPTIONAL, — Cond Split-

[0179] Bearer

[0180] }

[0181] UL-DataSplitThre shold :: = ENUMERATED { bO, blOO, b200, b400, b800, b!600, b3200, b6400, b!2800, b25600, b51200, b 102400, b 204800, b409600, b819200, bl 228800, bl 638400, b2457600, b 3276800, b4096000, b4915200, b 5734400, b6553600, infinity, spare8, spare7, spare6, spare5, spare4, spare3, spare2, spare 1}

[0182] SL-SRAP-Config-rl 9 ::= SEQ UENCE { sl-LocalIdentity-r!9 INTEGER (0..255) OPTIONAL, - Need M sl-MappingToAddModList-r!9 SEQUENCE (SIZE (L.maxLC-ID)) OF SL-

[0183] MappingToAddMod-rl9 OPTIONAL, - NeedN sl-MappingToReleaseList-rl9 SEQUENCE (SIZE (l..maxLC-ID)) OF SL-RemoteUE-RB- Identity-rl 7 OPTIONAL, - Need N }

[0184] SL-MappingToAddMod-rl 9 ::= SEQ UENCE { sl-Remote UE-RB-Identity-rl 7 SL-Remote UE-RB-Identity-rl 7, sl-EgressRLC-ChannelHopl-rl9 SEQUENCE (SIZE (l..maxLC-ID)) OF SL-RelayRLC- ChannelID-rl9 OPTIONAL, - Cond L2RelayUE sl-EgressRLC-ChannelHop2-rl9 SEQUENCE (SIZE (l..maxLC-ID)) OF SL-RelayRLC- ChannellD-rl 9 OPTIONAL, - Need N

[0185] }

[0186] SL-Remote UE-RB-Identity-rl 7 ::= CHOICE { srb-Identity-rl 7 INTEGER (0..3), drb-Identity-rl 7 DRB-Identity,

[0187] }

[0188] SL-RelayRLC-ChannelID-rl9 :: = INTEGER (L.maxLC-ID)

[0189] In the above ASN.l IE definition, sl-Localldentity may indicate the local UE ID of the remote UE 10, defined in the SRAP protocol TS 38.351. sl-RemoteUE-RB-Identity may indicate the end- to-end SRB / DRB identity of the data stream. sl-EgressRLC-ChcmnelHopl and sl-EgressRLC-Chcm- nelHop2 may indicate a list of relay RLC channels for the corresponding end-to-end SRB / DRB on each hop of the two adjacent hops of relay UE 12 in the transmission path. ul-DataSplitThreasholdHopl and ul-DataSplitThreasholdHop2 may indicate the threshold used to determine whether data split may be applied to split the user traffic over multiple relay RLC channels or not for the respective hop of the two hops which relay node bridges.

[0190] In a variant of the second embodiment, the target node may have an RLC bearer mapping table of multiple entries, where each entry may have the mapping information of one end-to-end SRB / DRB to the corresponding relay RLC channels for the last hop of the transmission path. Furthermore, the target node may have a threshold parameter to determine whether data split may be applied to multiple relay RLC channels or not. SL-L2TargetNode-Config-rl 9 ::= SEQ UENCE { sl-SRAP-ConfigTarget-rl9 SL-SRAP-Config-rl9 OPTIONAL, —NeedM ul-DataSplitThre shold UL-DataSplitThre shold OPTIONAL, — Cond SplitBearer

[0191] }

[0192] UL-DataSplitThre shold :: = ENUMERATED { bO, blOO, b200, b400, b800, b!600, b3200, b6400, b!2800, b25600, b51200, b 102400, b 204800, b409600, b819200, bl 228800, bl 638400, b2457600, b 3276800, b4096000, b4915200, b 5734400, b6553600, infinity, spare8, spare7, spare6, spare5, spare4, spare3, spare2, spare 1}

[0193] SL-SRAP-Config-rl 9 ::= SEQ UENCE { sl-LocalIdentity-r!9 INTEGER (0..255) OPTIONAL, - Need M sl-MappingToAddModList-rl9 SEQUENCE (SIZE (L.maxLC-ID)) OF SL-

[0194] MappingToAddMod-rl9 OPTIONAL, - NeedN sl-MappingToReleaseList-r!9 SEQUENCE (SIZE (L.maxLC-ID)) OF SL-RemoteUE-RB- Identity-rl 7 OPTIONAL, - Need N

[0195] SL-MappingToAddMod-rl 9 ::= SEQ UENCE { sl-Remote UE-RB-Identity-rl 7 SL-Remote UE-RB-Identity-rl 7, sl-EgressRLC-Channel-r!9 SEQUENCE (SIZE (L.maxLC-ID)) OF SL-RelayRLC-

[0196] ChannellD-rl 9 OPTIONAL, - Need N

[0197] SL-Remote UE-RB-Identity-rl 7 :: = CHOICE { srb-Identity-rl 7 INTEGER (0..3), drb-Identity-rl 7 DRB-Identity, SL-RelayRLC-ChannelID-rl9 :: = INTEGER (L.maxLC-ID)

[0198] In the above ASN.l IE definition, sl-SRAP-ConfigRemote may include the SRAP configuration of the target node (base station in L2 U2N Relay, target Remote UE in L2 U2U Relay) as defined in TS 38.351. sl-Localldentity may indicate the local UE ID of remote UE. sl-RemoteUE-RB-Identity may indicate the end-to-end SRB / DRB identity of the data stream. sl-EgressRLC-Channel may indicate a list of relay RLC channels for the corresponding end-to-end SRB / DRB on the last hop at the target node of the transmission path. ul-DataSplitThreashold may indicate the threshold user to determine whether data split may be applied to split the user traffic over multiple relay RLC channels or not.

[0199] In a variant of the second embodiment, the relay RLC channel may be a PC5 Relay RLC channel transmitting on a sidelink component carrier.

[0200] In a variant of the second embodiment, the relay RLC channel may be bi-directional.

[0201] In a variant of the second embodiment, the target node may be a base station.

[0202] In a variant of the second embodiment, the target node may be a Remote UE.

[0203] In a variant of the second embodiment, the relay RLC channel may be a Uu Relay RLC channel transmitting on a Uu component carrier of the MCG.

[0204] In a variant of the second embodiment, the relay RLC channel may be a Uu Relay RLC channel transmitting on a Uu component carrier of the SCG.

[0205] In a variant of the second embodiment, the gNB and / or gNB-DU / CU may configure the configuration information related to end-to-end packet duplication and / or data split / aggregation (or a subset thereof) to one or more (potential) nodes (e.g. source device, target device, intermediate / relay device) when such node is in the coverage of the base station.

[0206] In a variant of the second embodiment, the configuration information related to end-to- end packet duplication and / or data split / aggregation (or a subset thereof) may be preconfigured into a node (e.g. through a set of policies provided by the network or installed on the device).

[0207] In a variant of the second embodiment, the configuration information related to end-to- end packet duplication and / or data split / aggregation (or a subset thereof) may be configured via RRC signaling, MAC Control Elements, and / or SIB broadcasting and / or on-demand SIB request.

[0208] In a variant of the second embodiment, the configuration information related to end-to- end packet duplication and / or data split / aggregation (or subset thereof) may be configured in a node by receiving the configuration information (or subset thereof) from another node in the network (e.g. another node that is part of the transmission path), for example by receiving a PC5-RRC or other message containing such configuration information over the sidelink from a node has a direct link with the node. 1

[0209] In a variant of the second embodiment, the gNB and / or gNB-DU / CU may not necessarily need to signal the configuration to itself, as it may be some information stored in the memory or storage of the device.

[0210] In the second embodiment, the user data may be split according to the throughput and / or capacity of different relay RLC channels. A data split threshold (e.g., minimum / maximum amount of data, data rate, capacity, delay, jitter, reliability, transmission / reception error rate, or amount of frames lost) may be configured / used to determine whether the user traffic may be split on two and more RLC channels. The determination and / or applying the threshold may further include measuring the current performance (e.g., current data rate, signal strength, transmission / reception error rate, delay incurred, or amount of frames lost) for the various connections and / or RLC channels.

[0211] In another variant of the second embodiment, the user traffic may be split according to the desired data rate or desired reliability or desired error rate or the delay budget configured by a QoS policy on the user traffic, where such QoS policy may be applied by the upper layer at the SDAP entity.

[0212] In another variant of the second embodiment, a node in the transmission path may apply the QoS policy to other nodes of the transmission path.

[0213] In a fourth embodiment, Fig. 8B depicts an end-to-end data split and aggregation scheme between a source remote UE 10-S and a target remote UE 10-T for L2 U2U sidelink relay 12, where two hops exist (i.e., PC5 and PC5). On each hop, some data split and aggregation scheme may be used. For example, the first PC5 hop between the source remote UE 10-S and the relay UE 12 may use the side link carrier aggregation to transmit the split data (e.g., PDCP data packet) over multiple RLC channels on different sidelink component carriers; similarly, the second PC5 hop between the relay UE 12 and the target remote UE 10-T may use sidelink carrier aggregation as well to transmit the split data (e.g., PDCP data packet) over multiple RLC channels on different sidelink component carriers. At the transmitter side, the split PDCP data packet may transmit on multiple relay RLC channels on every hop of the transmission path; at the receiver side, the PDCP entity at the receiver may assemble the received PDCP data packet in sequence and only deliver the in-order PDCP SDU to the upper layer.

[0214] In the fourth embodiment, the user traffic may be split according to the throughput and / or capacity of different relay RLC channels. A threshold (also called a data split threshold) may be config - ured / used to determine whether the user traffic may be transmitted on one relay RLC channel or two and more relay RLC channels. The determination and / or applying the threshold may further include measuring the current performance (e.g., current data rate, signal strength, transmission / reception error rate, delay incurred, or amount of frames lost) for the various connections and / or RLC channels.

[0215] In a variant of the fourth embodiment, the user traffic may be split according to the delay budget configured by the QoS policy on the user traffic. The high latency relay RLC channel may transmit a smaller portion of the user traffic while the low latency relay RCL channel may transmit a larger portion of the user traffic. In a variant of the fourth embodiment, the user traffic may be split according to a round robin rule that each relay RLC channel may transmit the same amount of data.

[0216] In a variant of the fourth embodiment, the PDCP entity at the transmitter side may only randomly select one relay RLC channel to transmit PDCP data packet carrying the user traffic.

[0217] Since each hop may have different data split and aggregation scheme employed, and the number of alternative relay RLC channels on every hop may be different from hop to hop, there may be a need for each node in the transmission path to maintain a table to map the end-to-end SRBs / DRBs to the relay RLC channels on each hop of the transmission path.

[0218] In the fourth embodiment, the source node (e.g., the source remote UE 10-S) may have an RLC bearer mapping table of multiple entries, where each entry may have the mapping information of one end-to-end SRB / DRB to the corresponding relay RLC channels for the first hop of the transmission path. Furthermore, the source node (e.g., the source remote UE 10-S) may have a threshold parameter to determine whether data split may be applied to multiple relay RLC channels or not.

[0219] In a variant of the fourth embodiment, the relay node 12 may have an RLC bearer mapping table of multiple entries, where each entry may have the mapping information of one end-to-end SRB / DRB to the corresponding relay RLC channels for the two hops relay node bridges, at the relay node 12 of the transmission path. Furthermore, the relay node 12 may have a threshold parameter to determine whether data split may be applied to multiple relay RLC channels or not.

[0220] In a variant of the fourth embodiment, the target node (e.g., the target remote UE 10-T) may have an RLC bearer mapping table of multiple entries, where each entry may have the mapping information of one end-to-end SRB / DRB to the corresponding relay RLC channels for the last hop of the transmission path. Furthermore, the target node (e.g., the target remote UE 10-T) may have a threshold parameter to determine whether data split may be applied to multiple relay RLC channels or not.

[0221] END-TO-END PACKET TRANSMISSION BY ENFORCING QOS POLICY TO TRAFFIC FLOWS

[0222] In the first and / or second embodiment, Fig. 9 schematically shows a transmission of the packets from source node 10 (e.g., a U2N remote UE) to target node 20 (e.g., a gNB) by enforcing a QoS policy to the traffic flow in the case of an U2N relay 12, such as either applying packet duplication and / or data split and aggregation on each hop. The configuration may be configured by the pdcp-Duplication parameter to turn on and / or off the PDCP duplication on the hop and corresponding relay RLC channels, or ul-DataSplitThreshold parameter to split data traffic to multiple relay RLC channels at the transmitter side and assemble the PDCP data packet at the receiver side.

[0223] At the source node 10, QoS flows are mapped to IP packets (IP-P) and then radio bearers (RBs) are mapped to QoS flows. Then, PC5 Relay RLC channels are created and forwarded to the U2N relay 12 via PC5 sidelink radio bearers (PC5-SL-RBs). At the U2N relay 12, PC5 Relay RLC channels are mapped to Uu Relay RLC channels (Uu-RLC) and forwarded to the target node 20 via Uu radio bearers (Uu-RBs). At the target node 20, QoS flows are mapped to radio bearers and the QoS flows are supplied to an UPF which maps IP packets to the QoS flows.

[0224] In the third and / or fourth embodiment, Fig. 11 depicts the transmission of the packets from source node (e.g., source remote UE 10-S) to target node (e.g., target remote UE 10-T) by enforcing a QoS policy to the traffic flow in the case of an U2U relay 12, such as either applying packet duplication and / or data split and aggregation on each hop. The configuration may be configured by the pdcp-Duplica- tion parameter to turn on and / or off the PDCP duplication on the hop and corresponding relay RLC channels, or ul-DataSplitThreshold parameter to split data traffic to multiple relay RLC channels at the transmitter side and assemble the PDCP data packet at the receiver side.

[0225] At the source node 10-S, QoS flows are mapped to IP packets (IP-P) and then radio bearers (RBs) are mapped to QoS flows. Then, PC5 Relay RLC channels are created and forwarded to the U2U relay 12 via PC5 sidelink radio bearers (PC5-SL-RBs). At the U2U relay 12, PC5 Relay RLC input channels are mapped to PC5 Relay RLC output channels (Uu-RLC) and forwarded to the target node 10- T via PC5 sidelink radio bearers (PC5-SL-RBs). At the target node 10-T, QoS flows are mapped to radio bearers and IP packets are then mapped to the QoS flows.

[0226] In various embodiments, in a wireless network, a device (e.g., UE, either in-network coverage or out of coverage, also named as source node) may communicate with another device (e.g., base station, or another UE, also named as target node) via one or more relay nodes (e.g., relay UE), the transmission path between source node and target node may consist of one or more hops, a method of communication between source node and target node may include; a transmission path establishment step, where source node may initiate the discovery procedure to discover and select one or more relay node(s) to establish a transmission path to the target node, a configuration step, where an end-to-end packet duplication and / or data split and aggregation may be configured on each hop of the transmission path, and each hop may have multiple relay RLC channels, a transmission step between source node and target node, where in the case of packet duplication the same PDCP data packet may transmit on multiple relay RLC channels, and in the case of data split and aggregation the split PDCP data packet may transmit on multiple relay RLC channels respectively.

[0227] In an embodiment variant, the end-to-end transmission path may be established by each node in the transmission path to trigger its next immediately connected node to establish the connection and configure the packet duplication and / or data split and aggregation on scheme on the hop.

[0228] In an embodiment variant, the above packet duplication and / or data split and aggregation method may be activated / deactivated by RRC signaling. In an embodiment variant, the above packet duplication and / or data split and aggregation method may be activated according to the QoS flow indication of the data traffic from the application layer.

[0229] In an embodiment variant, the relay node discovery, selection and reselection criterion may include a parameter whether the relay node supports packet duplication and / or data split and aggregation mechanism on the hops where relay node is bridged / interconnected.

[0230] In an embodiment variant, the relay node discovery message may include a parameter indicating the support of end-to-end packet duplication and / or data split and aggregation, wherein this parameter may directly or indirectly indicate this end-to-end support. The relay service code may serve as such (indirect) indication.

[0231] In an embodiment variant, the network may broadcast the support of the proposed packet duplication and data split / aggregation scheme via SIB messages.

[0232] In an embodiment variant, the remote UE and the relay UE may indicate the capability of supporting the proposed packet duplication and data split / aggregation scheme in the UE Capability Information message sent to the network in the initial network attach procedure.

[0233] In an embodiment variant, the packet duplication mechanism in one hop of transmission path may be Uu carrier aggregation with PDCP duplication.

[0234] In an embodiment variant, the packet duplication mechanism in one hop of transmission path may be PC5 sidelink carrier aggregation with PDCP duplication.

[0235] In an embodiment variant, the packet aggregation mechanism in one hop of transmission path may be Uu carrier aggregation with split bearers.

[0236] In an embodiment variant, the packet aggregation mechanism in one hop of transmission path may be PC5 sidelink carrier aggregation with split bearers.

[0237] In an embodiment variant, the packet aggregation mechanism in one hop of transmission path may be Uu dual connectivity.

[0238] In an embodiment variant, the packet aggregation mechanism in one hop of transmission path may be non-3GPP UE-UE link.

[0239] Fig. 10 describes the protocol stack for the end-to-end packet duplication and / or data split / aggregation for sidelink relay U2N relay of the first and / or second embodiment. As can be gathered from Fig. 10, the Uu-RRC, Uu-SDAP and Uu-PDCP entities of the remote UE 10 and the base station 20 directly communicate with each other, while the PC5 entities of the remote UE 10 communicate with the higher layer Uu entities of the base station 20 via the relay UE 12 using PC5-RLC interface and Uu-RLC interface, respectively.

[0240] Fig. 12 describes the protocol stack for the end-to-end packet duplication and / or data split / aggregation for sidelink relay U2U relay of the third and / or fourth embodiment. As can be gathered from Fig. 12, the RRC, SDAP and PDCP entities of the source remote UE 10-S and the target remote UE 10-T directly communicate with each other, while the PC5 entities of the source remote UE 10-S communicate with the PC5 entities of the target remote UE 10-T via the relay UE 12 using respective PC5- RLC interfaces.

[0241] Fig. 13 schematically shows an end-to-end packet duplication and / or data split / aggrega- tion scheme for sidelink relay multi-hop relaying U2N relay, according to a fifth embodiment, where three successive relay UEs 12 are used between the remote UE 10 and the base station 20. Here, the same principles apply as discussed above in connection with the first and second embodiments.

[0242] Fig. 14 schematically shows an end-to-end packet duplication and data split / aggregation scheme for sidelink relay multi-hop relaying U2U relay, according to a sixth embodiment, where three successive relay UEs 12 are used between the source remote UE 10-S and the target remote UE 10-T. Here, the same principles apply as discussed above in connection with the third and fourth embodiments.

[0243] In further embodiments, the configuration of the packet duplication and data split / aggregation may configure one or more hops in the transmission path to use packet duplication (as described in connection with the first and third embodiments), and the rest of the hops in the transmission path to use data split / aggregation (as described in connection with the second and fourth embodiments).

[0244] Fig. 15 describes the protocol stack for an end-to-end packet duplication and / or data split / aggregation channel between a source remote UE 10-S and a target remote UE 10-T via two relay UEs 20, according to a seventh embodiment. As can be gathered from Fig. 15, PDCP entities of the source remote UE 10-S and the target remote UE 10-T directly communicate with each other, while their RLC entities are connected via RLC entities of the two successive relay UEs 20.

[0245] In Fig. 16, a potential deployment scenario for various of the above embodiments is described, wherein a first relay device 1601 and a second relay device 1602 (such as two satellite relays or the like) are used for relaying a communication path between a source UE 1603 and a target UE 1604. Two respective communication links 1607 and 1608 are provided between the first relay device 1601 and the source UE 1603 and the target UE 1604. Two further respective communication links 1609 and 1610 are provided between the second relay device 1602 and the source UE 1603 and the target UE 1604. Furthermore, the scenario comprises an access device (e.g., base station or satellite gateway) 1605 of a radio access network and a core network 1606.

[0246] In the deployment scenario of Fig. 16, the traffic exchanged between the source UE 1603 and the target UE 1604 can be split and / or duplicated through multipath connections as described in connection with the above embodiments.

[0247] Fig. 17 shows a protocol stack for enabling traffic splitting / duplication in at least some of the above embodiments by using multipath-TCP and / or multipath QUIC between a source UE 1701 and a target UE 1703 over at least one relay device 1702 that may be a UE-to-UE relay or another type of relay.

[0248] Here, the source UE 1701, the relay device 1702 and the target UE 1703 are connected via a 5G access network (5G-AN) protocol layers (for 3GPP access and non-3GPP access) to thereby enable communication between the source UE 1701 and the target UE 1703 on higher protocol layers, such as Internet Protocol (IP), User Datagram Protocol (UDP), Multipath-QUIC (MPQUIC) Transport Layer Security (TLS), Hypertext Transfer Protocol version 3 (HTTP / 3) and PDU.

[0249] In an embodiment variant related to UE-to-UE communication embodiments, the source and target UE may establish a first path over a first relay, the source and target UE negotiate the addition of a second path over a second relay (instead of doing a standard path switching), the source and target UE establish the second path, and the source and target UE establish a multipath link over the first and second relay.

[0250] In a related embodiment variant, the source and target UEs may be connected through two IP address pairs when an IP address pair corresponds to the first path and the second IP address pair corresponds to the second path, and the IP address pairs are used in combination with multipath QUIC or multipath TCP.

[0251] In a related embodiment variant, the multipath QUIC connection between source and target UEs may encapsulate UDP packets that are exchanged between source and target UE.

[0252] To summarize, methods and systems have been presented for enhanced reliability and throughput when using relay devices such as cellular relay devices such as sidelink relay communication in the cellular network, or other relay devices such as an access device or satellite.

[0253] Although the embodiments were described in the context of a 5G network, their applications are not limited to such a type of network. They may be applied to any type of wireless or cellular network which provides suitable options for end-to-end packet duplication and / or data split / aggregation over multiple hops.

[0254] Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claims, from a study of the drawings, the disclosure and the appended claims. In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. A single processor or other unit may fulfil the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. The foregoing description details certain embodiments. It will be appreciated, however, that no matter how detailed the foregoing appears in the text, these embodiments may be practiced in many ways and is therefore not limited to the embodiments disclosed. It should be noted that the use of particular terminology when describing certain features or aspects should not be taken to imply that the terminology is being re-defined herein to be restricted to include any specific characteristics of the features or aspects with which that terminology is associated. Additionally, the expression “at least one of A, B, and C” is to be understood as disjunctive, i.e., as “A and / or B and / or C”. A single unit or device may fulfil the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

[0255] The described operations like those indicated in the above embodiments may be imple- mented as program code means of a computer program and / or as dedicated hardware of the related network device or function, respectively. The computer program may be stored and / or distributed on a suitable medium, such as an optical storage medium or a solid-state medium, supplied together with or as part of other hardware, but may also be distributed in other forms, such as via the Internet or other wired or wireless telecommunication systems.

Claims

CLAIMS:

1. A first communication device for a wireless network, wherein the first communication device supports end-to-end packet duplication and / or data split / aggregation over multiple hops, the first communication device being adapted to: establish one or more communication paths between the first and a second communication device; and receive configuration information from another communication device in the wireless network, wherein the configuration information comprises at least one parameter about the end-to-end packet duplication and / or the data split / aggregation over the one or more communication paths between the first communication device and the second communication device, and over one or more communication paths between the first communication device and at least one third communication device and / or between the at least one third communication device and the second communication device; and perform at least one of the following based on the configuration information: establish one or more communication paths between the first communication device and the at least one third communication device based on the configuration information; or transmit configuration information to the second communication device comprising at least one parameter about the end-to-end packet duplication and / or the data split / aggregation over the one or more communication paths between the at least one third communication device and the second communication device; or transmit / receive data over the one or more communication paths between the first communication device and the at least one third communication device and / or between the at least one third communication device and the second communication device, by duplicating and / or splitting the data on one or more communication paths between the first communication device and the at least one third communication device and / or between the at least a third communication device and the second communication device and depending on the configuration information.

2. The first communication device of claim 1, wherein the one or more communication paths between the first communication device and the second communication device are one or more direct wireless connections or radio link control, RLC, channels between the first communication device and the second communication device and / or one or more indirect wireless connections or relayed RLC channels between the first communication device and the second communication device via the at least one third communication device.

3. The first communication device of any preceding claim, wherein the second communication device is not a destination endpoint of transmitted duplicated / split data and is not an originating source of received duplicated / split data.4 The first communication device of any preceding claim, wherein the at least one parameter about the end-to-end packet duplication over the one or more communication paths comprises a quality of service, QoS, policy and / or a duplication threshold.

5. The first communication device of any preceding claim, wherein the at least one parameter about the data split / aggregation over the one or more communication paths comprises a QoS policy and / or a data split threshold.

6. A base station device in a wireless network, wherein the base station device supports end- to-end packet duplication and / or data split / aggregation over a wireless link to one more communication devices, the base station device being adapted to: connect to a first communication device directly if the base station device has a direct communication path with the first communication device; and connect to the first communication device indirectly if the base station device has an indirect communication path with the first communication device via one or more second communication devices; and establish one or more communication paths between the first communication device and the base station device; and configure the first communication device and the one or more second communication devices with at least one parameter about the end-to-end packet duplication and / or the data split / aggregation over the one or more communication paths between the first communication device and the base station device, and / or between the first communication device or the base station device and the one or more second communication devices.

7. The base station device of claim 5, further adapted to perform at least one of the following based on the configuration information: establish one or more communication paths between the first or the one or more second communication devices based on the configuration information; or transmit / receive data over the one or more communication paths between the first communication device, the base station device and the one or more second communication devices, by duplicating and / or splitting the data on one or more communication paths between the first communicationdevice, the base station device and the one or more second communication devices depending on the configuration information.

8. A method of end-to-end packet duplication and / or data split / aggregation in a wireless network, the method comprising: establishing one or more communication paths between a first communication device and a second communication device; receiving configuration information from another communication device in the wireless network, wherein the configuration information includes at least one parameter about the end-to-end packet duplication and / or the data split / aggregation over the one or more communication paths between the first communication device and the second communication device, and over one or more communication paths between the first communication device and at least one third communication device and / or between the at least one third communication device and the second communication device; and performing at least one of the following based on the configuration information: establishing one or more communication paths between the first communication device and the at least one third communication device based on the configuration information; or transmitting configuration information to the second communication device comprising at least one parameter about the end-to-end packet duplication and / or the data split / aggregation over the one or more communication paths between the at least one third communication device and the second communication device; or transmitting / receiving data over the one or more communication paths between the first communication device and the at least one third communication device and / or between the at least one third communication device and the second communication device, by duplicating and / or splitting the data on one or more communication paths between the first communication device and the at least one third communication device and / or between the at least one third communication device and the second communication device depending on the configuration information.

9. A computer program product comprising code means for producing the steps of claim 8 when run on a computer device.

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