WO2023280978A2

WO2023280978A2 - Packet duplication technique

Info

Publication number: WO2023280978A2
Application number: PCT/EP2022/068907
Authority: WO
Inventors: Min Wang; Antonino ORSINO
Original assignee: Telefonaktiebolaget Lm Ericsson (Publ)
Priority date: 2021-07-08
Filing date: 2022-07-07
Publication date: 2023-01-12
Also published as: WO2023280978A3

Abstract

A technique for transmitting duplicated packets on a dual connectivity, DC (1500), of a wireless device (100) is described. As to a method aspect of the technique, at least one packet of the duplicated packets is transmitted over a first path (1510) of the DC (1500), wherein the first path (1510) of the DC (1500) is wirelessly connected from the wireless device (100; 1900; 2191; 2192; 2230) towards a first peer wireless device (210) using a first sidelink, SL (1512), between the wireless device (100; 1900; 2191; 2192; 2230) and the first peer wireless device (210). At least one packet of the duplicated packets is transmitted over at least one secondary path (1520) of the DC (1500), wherein each of the at least one packet over the at least one secondary path (1520) is a duplication of each of the at least one packet over the first path (1510), wherein the at least one secondary path (1520) of the DC (1500) is wirelessly connected from the wireless device (100; 1900; 2191; 2192; 2230) towards at least one station (220) other than the first peer wireless device (210).

Description

Packet Duplication Technique

Technical Field

The present disclosure relates to a technique for packet duplication on a dual connectivity of a wireless device. More specifically, and without limitation, methods and devices are provided for transmitting and receiving duplicated packets on a dual connectivity of a wireless device.

Background

The Third Generation Partnership Project (3GPP) defined sidelinks (SLs) in Release 12 as an adaptation of the Long Term Evolution (LTE) wireless (e.g., radio) access technology for direct communication between two wireless device (e.g., radio devices), also referred to as user equipment (UE), without going through a network node (e.g., a base station). Such device-to-device (D2D) communications through SLs are also referred to as proximity service (ProSe) and can be used for Public Safety communications. While conventional public safety communications use different standards in different geographical regions and countries, 3GPP SL communications enable interworking of different public safety groups. 3GPP has enriched SLs in Release 13 for public safety and commercial communication use-cases and, in Release 14, for vehicle-to-everything (V2X) scenarios.

A SL relay is standardized by 3GPP for NR Release 17, which enables a remote UE to be able to connect to a network node (e.g., a gNB) via a relay UE. The remote UE may be in coverage (1C) or out of coverage (OOC).

For 3GPP Release 18, using SL in order to improve reliability and latency of the Uu connectivity, i.e., the wireless connection between wireless UE and gNB has been proposed. A possible solution to do it is to integrate sidelink with the dual connectivity features that has been standardized for NR during Release 15, but that is restricted only to the presence of two legs, one towards the master cell group (MCG) and another one towards the secondary cell group (SCG).

Given the SCG will most likely be deployed on high frequencies, the chance of incurring in radio link failure is high and using sidelink may mitigate such phenomena and provide also a valid alternative to recover the failed connectivity.

Summary

Accordingly, there is a need for a technique that improves at least one of reliability and latency for a wireless device using a SL in DC.

As to a first method aspect, a method of transmitting duplicated packets on a dual connectivity (DC) of a wireless device is provided. The method comprises or initiates a step of transmitting at least one packet of the duplicated packets over a first path of the DC. The first path of the DC is wirelessly connected from the wireless device towards a first peer wireless device using a first sidelink (SL) between the wireless device and the first peer wireless device. The method further comprises or initiates a step of transmitting at least one packet of the duplicated packets over at least one secondary path of the DC. Each of the at least one packet over the at least one secondary path is a duplication of each of the at least one packet over the first path. The at least one secondary path of the DC is wirelessly connected from the wireless device towards at least one station other than the first peer wireless device.

The method may be performed by the wireless device.

As to a second method aspect, a method of receiving duplicated packets on a dual connectivity (DC) of a wireless device is provided. The method comprises or initiates a step of receiving at least one packet of the duplicated packets over a first path of the DC. The first path of the DC is wirelessly connected from the wireless device towards a first peer wireless device using a first sidelink (SL) between the wireless device and the first peer wireless device. Alternatively or in addition, the method comprises or initiates a step of receiving at least one packet of the duplicated packets over at least one secondary path of the DC. The at least one secondary path of the DC is wirelessly connected from the wireless device towards at least one station other than the first peer wireless device. The method further comprises or initiates a step of discarding at least one of the received duplicated packets. The method (e.g., according to the second method aspect) may be performed by an intermediate node of the first path or the at least one secondary path. Alternatively or in addition, the method may be performed by the destination node of the transmission or of the first path or of the at least one secondary path.

The second method aspect may further comprise any feature and/or any step disclosed in the context of the first method aspect, or a feature and/or step corresponding thereto, e.g., a receiver counterpart to a transmitter feature or step.

The second method aspect may be implemented alone or in combination with any one of the detailed embodiments.

As to another aspect, a computer program product is provided. The computer program product comprises program code portions for performing any one of the steps of the first and/or second method aspect disclosed herein when the computer program product is executed by one or more computing devices. The computer program product may be stored on a computer-readable recording medium. The computer program product may also be provided for download, e.g., via the radio network, the RAN, the Internet and/or the host computer. Alternatively, or in addition, the method may be encoded in a Field-Programmable Gate Array (FPGA) and/or an Application-Specific Integrated Circuit (ASIC), or the functionality may be provided for download by means of a hardware description language.

As to a first device aspect, a wireless device transmitting duplicated packets on a dual connectivity (DC) of the wireless device is provided. The wireless device comprises memory operable to store instructions and processing circuitry operable to execute the instructions, such that the wireless device is operable to transmit at least one packet of the duplicated packets over a first path of the DC. The first path of the DC is wirelessly connected from the wireless device towards a first peer wireless device using a first sidelink (SL) between the wireless device and the first peer wireless device. The wireless device is further operable to transmit at least one packet of the duplicated packets over at least one secondary path of the DC. Each of the at least one packet over the at least one secondary path is a duplication of each of the at least one packet over the first path. The secondary path of the DC is wirelessly connected from the wireless device towards at least one station other than the first peer wireless device.

The wireless device (e.g., according to the first device aspect) may be further operable to perform any one of the steps of the first method aspect.

Alternatively or in addition, a wireless device configured to perform the first method aspect is provided.

As to a second device aspect, a node for receiving duplicated packets on a dual connectivity (DC) of a wireless device is provided. The node comprising memory operable to store instructions and processing circuitry operable to execute the instructions, such that the node is operable to receive at least one packet of the duplicated packets over a first path of the DC. The first path of the DC is wirelessly connected from the wireless device towards a first peer wireless device using a first sidelink (SL) between the wireless device and the first peer wireless device. Alternatively or in addition, the node is operable to receive at least one packet of the duplicated packets over at least one secondary path of the DC. The secondary path of the DC is wirelessly connected from the wireless device towards at least one station other than the first peer wireless device. The node is further operable to discard at least one of the received duplicated packets.

The node may be an intermediate node or a destination node. Alternatively or in addition, the node may be a node of the first path or a node of the at least one secondary path. The node may be a network or a further wireless device (e.g., the peer wireless device). Alternatively or in addition, the node may be a destination node or an intermediate node of the transmission on the first path or the at least one secondary path.

The node (e.g., according to the second device aspect) may further comprise any feature, or may be operable to perform any step, of the second method aspect.

Alternatively or in addition, a node configured to perform the second method aspect is provided.

The device aspects may be implemented alone or in combination with any one of the claims and/or any one of the detailed embodiments. As to a still further aspect a communication system including a host computer is provided. The host computer comprises a processing circuitry configured to provide user data, e.g., included in or related to the duplicated packets. The host computer further comprises a communication interface configured to forward the data to a cellular network (e.g., the RAN and/or the base station) for transmission to a UE. A processing circuitry of the cellular network is configured to execute any one of the steps of the first and/or second method aspects. The UE comprises a radio interface and processing circuitry, which is configured to execute any one of the steps of the first and/or second method aspects.

The communication system may further include the UE. Alternatively, or in addition, the cellular network may further include one or more base stations configured for radio communication with the UE and/or to provide a data link between the UE and the host computer using the first and/or second method aspects.

The processing circuitry of the host computer may be configured to execute a host application, thereby providing the data and/or any host computer functionality described herein. Alternatively, or in addition, the processing circuitry of the UE may be configured to execute a client application associated with the host application.

Any one of the devices (e.g., the wireless devices or UEs), the network node (e.g., a base station), the communication system or any node or station for embodying the technique may further include any feature disclosed in the context of the method aspect, and vice versa. Particularly, any one of the units and modules disclosed herein may be configured to perform or initiate one or more of the steps of the method aspect.

Brief Description of the Drawings

Further details of embodiments of the technique are described with reference to the enclosed drawings, wherein:

Fig. 1 shows a schematic block diagram of an embodiment of a device for transmitting duplicated packets on a dual connectivity; Fig. 2 shows a schematic block diagram of an embodiment of a device for receiving duplicated packets on a dual connectivity; Fig. 3 shows a flowchart for an embodiment of a method of transmitting duplicated packets on a dual connectivity, which method may be implementable by the device of Fig. 1;

Fig. 4 shows a flowchart for an embodiment of a method of receiving duplicated packets on a dual connectivity, which method may be implementable by the device of Fig. 2;

Fig. 5 schematically illustrates a first example of a wireless network comprising embodiments of the devices of Figs. 1 and 2 for performing the methods of Figs. 3 and 4, respectively;

Fig. 6 schematically illustrates options for dual connectivity;

Fig. 7 schematically illustrates embodiments of the devices of Figs. 1 and 2 using dual connectivity;

Fig. 8 schematically illustrates first examples of radio bearers usable by embodiments of the devices of Figs. 1 and 2 for dual connectivity; Fig. 9 schematically illustrates second examples of radio bearers usable by embodiments of the devices of Figs. 1 and 2 for dual connectivity;

Fig. 10 schematically illustrates embodiments of the devices of Figs. 1 and 2 using dual connectivity;

Fig. 11 schematically illustrates an example of a sidelink relay;

Fig. 12 schematically illustrates an example of a sidelink relay; Fig. 13 schematically illustrates an example of a sidelink relay; Fig. 14 schematically illustrates embodiments of the devices of Figs. 1 and 2 using dual connectivity;

Fig. 15 schematically illustrates embodiments of the devices of Figs. 1 and 2 using dual connectivity;

Fig. 16 schematically illustrates embodiments of the devices of Figs. 1 and 2 using dual connectivity;

Fig. 17 schematically illustrates embodiments of the devices of Figs. 1 and 2 using dual connectivity;

Fig. 18 schematically illustrates embodiments of the devices of Figs. 1 and 2 using dual connectivity;

Fig. 19 shows a schematic block diagram of a wireless device embodying the device of Fig. 1;

Fig. 20 shows a schematic block diagram of a network node embodying the device of Fig. 2;

Fig. 21 schematically illustrates an example telecommunication network connected via an intermediate network to a host computer;

Fig. 22 shows a generalized block diagram of a host computer communicating via a base station or radio device functioning as a gateway with a user equipment over a partially wireless connection; and

Figs. 23 and 24 show flowcharts for methods implemented in a communication system including a host computer, a base station or radio device functioning as a gateway and a user equipment.

Detailed Description

In the following description, for purposes of explanation and not limitation, specific details are set forth, such as a specific network environment in order to provide a thorough understanding of the technique disclosed herein. It will be apparent to one skilled in the art that the technique may be practiced in other embodiments that depart from these specific details. Moreover, while the following embodiments are primarily described for a New Radio (NR) or 5G implementation, it is readily apparent that the technique described herein may also be implemented for any other radio communication technique, including a Wireless Local Area Network (WLAN) implementation according to the standard family IEEE 802.11, 3GPP LTE (e.g., LTE-Advanced or a related radio access technique such as MulteFire), for Bluetooth according to the Bluetooth Special Interest Group (SIG), particularly Bluetooth Low Energy, Bluetooth Mesh Networking and Bluetooth broadcasting, for Z-Wave according to the Z-Wave Alliance or for ZigBee based on IEEE 802.15.4.

Moreover, those skilled in the art will appreciate that the functions, steps, units and modules explained herein may be implemented using software functioning in conjunction with a programmed microprocessor, an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), a Digital Signal Processor (DSP) or a general purpose computer, e.g., including an Advanced RISC Machine (ARM). It will also be appreciated that, while the following embodiments are primarily described in context with methods and devices, the invention may also be embodied in a computer program product as well as in a system comprising at least one computer processor and memory coupled to the at least one processor, wherein the memory is encoded with one or more programs that may perform the functions and steps or implement the units and modules disclosed herein.

Fig. 1 schematically illustrates a block diagram of an embodiment of a device for transmitting duplicated packets on a dual connectivity (DC). The device is generically referred to by reference sign 100.

The device 100 comprises the modules 102 and 104 indicated in Fig. 1 that perform the respective steps of the first method, e.g. according to Fig. 3.

Any of the modules of the device 100 may be implemented by units configured to provide the corresponding functionality.

The device 100 may also be referred to as, or may be embodied by, the wireless device 100 (or briefly: UE 100). The UE 100 and the at least one station may be in direct radio communication. The at least one station may be embodied by the device 220.

Fig. 2 schematically illustrates a block diagram of an embodiment of a device for receiving duplicated packets on a DC. The device is generically referred to by reference sign 220.

The device 220 comprises the modules 202 and 204 indicated in Fig. 2 that perform the respective steps of the second method, e.g. according to Fig. 4.

Any of the modules of the device 220 may be implemented by units configured to provide the corresponding functionality.

The device 220 may also be referred to as, or may be embodied by, a node, e.g., the at least one station and/or the first peer wireless device (also referred to by reference sign 210). The node 220 (e.g., a network node or a further wireless device) and the wireless device 100 may be in direct radio communication or SL radio communication or relayed radio communication. The wireless device may be embodied by the device 100.

Fig. 3 shows an example flowchart for a method 300 of performing the first method aspect, i.e., a method of transmitting duplicated packets on a dual connectivity (DC) of a wireless device.

The method 300 comprises the steps 302 and 304, e.g., as indicated in Fig. 3.

For example, in a step 302 of the method 300, at least one packet of the duplicated packets is transmitted over a first path of the DC. The first path of the DC is wirelessly connected from the wireless device towards a first peer wireless device using a first sidelink (SL) between the wireless device and the first peer wireless device.

The method 300 further comprises a step 304 of transmitting at least one packet of the duplicated packets over at least one secondary path of the DC. Each of the at least one packet over the at least one secondary path is a duplication of each of the at least one packet over the first path. The at least one secondary path of the DC is wirelessly connected from the wireless device towards at least one station other than the first peer wireless device.

The method 300 may be performed by the device 100. For example, the modules 102 and 104 may perform the steps 302 and 304, respectively.

Fig. 4 shows an example flowchart for a method 400 of performing the second method aspect, i.e., a method of receiving duplicated packets on a dual connectivity (DC) of a wireless device.

The method 400 comprises the steps 402 (e.g., including at least one of the sub steps 402-1 and 402-2) and 404, e.g., as indicated in Fig. 4.

For example, the method comprises a step 402-1 of receiving at least one packet of the duplicated packets over a first path of the DC. The first path of the DC is wirelessly connected from the wireless device towards a first peer wireless device using a first sidelink (SL) between the wireless device and the first peer wireless device. Alternatively or in addition, the method comprises a step 402-2 of receiving at least one packet of the duplicated packets over at least one secondary path of the DC. The at least one secondary path of the DC is wirelessly connected from the wireless device towards at least one station other than the first peer wireless device.

The method further comprises a step 404 of discarding at least one of the received duplicated packets.

The method 400 may be performed by the device 220. For example, the modules 202 and 204 may perform the steps 402 and 404, respectively.

In any aspect, the at least one packet over the first and the at least one packet over the at least one secondary path may be collectively referred to as duplicated packets (or briefly: packets) or duplicates.

The transmitting of the at least one packet over the at least one secondary path of the DC may comprise transmitting at least one packet over each of the at least one secondary path of the DC, optionally wherein each packet over the at least one secondary path is a duplication of each of the at least one packet over the first path. The duplicated packets may comprise a sequence of two or more than two duplicated packets, e.g., the packet over the first path and at least one packet over the at least one secondary path, or a sequence of two or more packets over the first path and/or a sequence of two or more packets over the at least one secondary path.

Transmitting the duplicated packets may also be referred to as duplication active or activated duplication.

The duplication of packets may mean that a payload and/or a service data unit (SDU) of the respective packet is identical in each of the duplicated packets.

The method 300 may further comprise or initiate at least one of the steps of: establishing the first path; generating the at least one packet to be transmitted on the first path; establishing the at least one secondary path; and generating the at least one packet to be transmitted on the at least one secondary path.

The DC may comprise the first path and the at least one secondary path that is different from the first path. The first path and the at least one secondary path may be disjoint, e.g., except for its ends including the wireless device.

The first path of the DC may be wirelessly connected directly towards the first peer wireless device using the first SL. That is, the first path of the DC may be directly connected towards the first peer wireless device using the wireless first SL.

The at least one secondary path of the DC may be wirelessly connected directly towards the at least one station. That is, the at least one secondary path of the DC may be directly connected towards the at least one station using a wireless interface other than the first SL, e.g. a wireless second SL or an uplink or a downlink or a Uu interface.

Herein, wirelessly connected may refer to a propagation of electromagnetic waves, e.g., including at least one of reflection, refraction, diffraction, and attenuation. Directly connected may refer to the propagation of electromagnetic waves without intermediate retransmission, relaying, or amplification. Herein, the words "at least one" may refer to the alternative "one" or the alternative "more than one". E.g., the at least one station may be one station.

The wireless connection of the first path (e.g., the first SL) may comprise a radio connection (or communication, e.g., a radio link) or a free-space optical connection (or communication, e.g., an optical link). Alternatively or in addition, the wireless connection of the at least one secondary path (e.g., between the wireless device and the at least one station) may comprise a radio connection (or communication, e.g., a radio link) or a free-space optical connection (or communication, e.g., an optical link).

The first SL may comprise a PC5 interface between the wireless device and the first peer wireless device.

The one or each of the at least one station may be the destination node (or briefly: destination) of the respective one of the at least one secondary path. Alternatively or in addition, the wireless device may be the destination of the first path.

A master node may terminate the first path. A secondary node may terminate the at least one secondary path. Alternatively or in addition, a master node may terminate the at least one secondary path. A secondary node may terminate the first path.

The wireless device may have the first path and the at least one secondary path as two or more active links at the same time, e.g., one over the Uu interface and another one over the PC5 interface.

Herein, the wireless device may also be referred to as a source node. The wireless device may be part of a communication chain, in which case the wireless device may also act as a receiving node that forwards a received message using the DC.

Herein, the paths may also be referred to as connections. The established paths of the DC may be collectively referred to as the DC connection.

Multi-connectivity may be an example of the DC. Herein, node or station may be an umbrella term for a wireless device (e.g., a user equipment) and a network node (e.g., a base station).

The wireless device may be a radio device, e.g., a user equipment (UE).

The at least one station and/or the at least one further station may be a network node, e.g., a base station, e.g., a next generation node B (gNodeB or gNB).

The wireless access network may be a radio access network (RAN).

The at least one or each of the duplicated packets (e.g., according to the first method aspect) may comprise or may be indicative of at least one of:

- an indication that the respective packet is a duplicated packet or that the duplication is activated;

- an indication of whether or not the respective packet is a duplicated packet or whether or not the duplication is activated;

- a total number of the duplicated packets generated or transmitted for the respective packet;

- a packet identifier (ID) of the respective packet;

- a packet sequence number (SN) of the respective packet;

- whether the respective packet is the first packet transmitted or to be transmitted among the duplicated packets;

- whether the respective packet is the last packet transmitted or to be transmitted among the duplicated packets;

- a packet time stamp indicative of a time when the respective packet has been transmitted by the wireless device;

- a packet time stamp indicative of a time when the respective packet has been generated, optionally by the wireless device;

- a traffic ID of a type of traffic to which the respective packet or the duplicated packets belong;

- a service ID of a service using the packets;

- a QoS ID of a quality of service (QoS) associated with the packets;

- a source node ID of a source node of the respective packet;

- a source node ID of the wireless device; and

- a destination node ID of a destination node of the respective packet.

The QoS ID may be a QoS Class ID (QCI). The source node of the respective packet may be a wireless device or a node upstream to the duplication, e.g., a source node of a packet triggering or underlying the duplicated packets.

The destination node may be one of the at least one station or the first peer wireless device.

The method (e.g., according to the first method aspect) may be performed by the wireless device.

The transmitting of the at least one packet over the first path (e.g., according to the first method aspect) may be prior to or may start earlier than the transmitting of the at least one packet over the at least one secondary path. Alternatively, the transmitting of the at least one packet over the at least one secondary path may be prior to or may start earlier than the transmitting of the at least one packet over the first path. Alternatively or in addition, the duplicated packets may be sequentially transmitted on the first and secondary paths.

The at least one packet over the at least one secondary path (e.g., according to the first method aspect) may be transmitted responsive to an absent or outstanding acknowledgment of the at least one packet transmitted over the first path. Alternatively or in addition, the at least one packet over the first path may be transmitted responsive to an absent or outstanding acknowledgment of the at least one packet transmitted over the at least one secondary path.

Herein, the acknowledgment may be absent or outstanding if no positive acknowledgment (ACK) is received (e.g., within a predefined time period after transmission) or if a negative acknowledgment (NACK) is received.

The at least one secondary path (e.g., according to the first method aspect) may comprise a first secondary path and a second secondary path. The transmitting of the at least one packet over the at least one secondary path of the DC may comprise transmitting at least one packet of the duplicated packets over the first secondary path. Each of the at least one packet over the first secondary path may be a duplication of each of the at least one packet over the first path; and responsive to an absent or outstanding acknowledgment of the at least one packet transmitted over the first secondary path, transmitting at least one packet of the duplicated packets over the second secondary path. Each of the at least one packet over the second secondary path may be a duplication of each of the at least one packet over the first path.

The wireless device (e.g., according to the first method aspect) may stop transmitting on all the first and secondary paths and/or may release all the first and secondary paths, if no acknowledgement of the transmitted at least one packet is received via any of the first and secondary paths.

Stopping the transmitting may refer to stopping the transmitting of the at least one packets of the duplicated packets.

The wireless device (e.g., according to the first method aspect) may stop transmitting on a subset of the first and secondary paths and/or may release a subset of the first and secondary paths. The subset may comprise those paths via which no acknowledgement of the transmitted at least one packet is received.

The at least one packet over the first path (e.g., according to the first method aspect) may be transmitted simultaneously with the transmitting of the at least one packet over the at least one secondary path.

The method (e.g., according to the first method aspect) may further comprise or initiate the steps of starting a timer upon the transmitting of the at least one packet of the duplicated packets over the first path and/or the at least one secondary path.

The wireless device (e.g., according to the first method aspect) may stop transmitting on all the first and secondary paths and/or may release all the first and secondary paths, if no acknowledgement of the transmitted packet is received via any of the first and secondary paths upon expiry of the timer.

Starting the timer may comprise setting the timer to a predefined time period, wherein the started timer is counting down and expires upon arriving at zero. Alternatively or in addition, starting the timer may comprise setting the timer to zero, wherein the started timer is counting up and expires upon arriving at a predefined time period. The wireless device (e.g., according to the first method aspect) may stop transmitting on a subset of the first and secondary paths and/or may release a subset of the first and secondary paths. The subset may comprise those paths via which no acknowledgement of the transmitted at least one packet is received upon expiry of the timer.

The wireless device (e.g., according to the first method aspect) may keep transmitting on a subset of the first and secondary paths after expiry of the timer. The subset may comprise those paths via which an acknowledgement of the transmitted at least one packet has been received upon expiry of the timer.

To keep transmitting (e.g., to further transmit) on the subset of the first and secondary paths may comprise transmitting the same data as, or data other than, the data included in the duplicated packets until expiry of the time or when starting the timer. For example, the same data may be transmitted in a sequence of duplicated packets.

The transmission of the duplicated packets (e.g., according to the first method aspect) may comprise transmitting the duplicated packets on all the first and secondary paths at a periodic interval and/or may be triggered by a duplication condition, optionally as long as the timer is not expired.

The sequence of duplication packets may comprise the duplicated packets transmitted at the periodic interval and/or triggered by the duplication condition.

The wireless device (e.g., according to the first method aspect) may perform the transmission of the duplicated packets if or as long as a duplication conditions is fulfilled.

Performing the transmission of the duplicated packets, i.e. performing the steps 302 and/or 304 of transmitting the duplicated packets, or performing the method 300, may also be referred to as activating the duplication or operating the wireless device with activated duplication.

The method 300 (e.g., according to the first method aspect) may further comprise or initiate, responsive to a first acknowledgement of the transmitted at least one packet received via one of the first and secondary paths, at least one of the steps of stopping the transmission of the duplicated packets over all of the first and secondary paths; and releasing each of the first and secondary paths except for the path via which the first acknowledgement of the transmitted at least one packet has been received.

Herein, the first and secondary paths may encompass the first path and the at least one secondary path.

The step 302 of transmitting the at least one packet of the duplicated packets over the first path (e.g., according to the first method aspect) may comprise transmitting a sequence of the duplicated packets over the first path. The step of transmitting 304 the at least one packet of the duplicated packets over the at least one secondary path (e.g., according to the first method aspect) may comprise transmitting a sequence of the duplicated packets over the at least one secondary path.

Each of the packets in the sequence may be a duplication of any other packet in the sequence. The packet ID may be the same for all packets in the sequence. The packet SN may be different for different packets in the sequence.

The at least one station (e.g., according to the first method aspect) may be or may comprise one or more network nodes or one or more cell groups, and/or wherein a wireless access network may comprise the at least one station.

The at least one station (e.g., according to the first method aspect) may be or may comprise at least one of a master node of the DC, a master cell group (MCG) of the DC, a secondary node of the DC, and a secondary cell group (SCG) of the DC.

The at least one secondary path of the DC (e.g., according to the first method aspect) may be wirelessly connected towards the at least one station using at least one of an uplink, a downlink, and a Uu interface between the wireless device and the at least one station.

The first peer wireless device (e.g., according to the first method aspect) may be a relay wireless device relaying the first path of the DC from the wireless device to the at least one station and/or to the wireless access network comprising the at least one station.

The at least one secondary path (e.g according to the first method aspect) may be wirelessly connected towards one station, and the first path of the DC may be relayed to the one station. The one station may be or may comprise both a master node and a secondary node of the DC of the wireless device.

The at least one station (e.g., according to the first method aspect) may be at least one network node of a wireless access network. The first peer wireless device may be a relay wireless device relaying the first path of the DC from the wireless device to at least one further network node of the wireless access network comprising the at least one network node.

The at least one further network node (e.g according to the first method aspect) may be or may comprise a master node of the DC of the wireless device. The at least one a station may be or may comprise at least one secondary node of the DC of the wireless device.

The at least one further network node (e.g., according to the first method aspect) may be or may comprise at least one secondary node of the DC of the wireless device. The at least one a station may be or may comprise a master node of the DC of the wireless device.

The at least one station (e.g., according to the first method aspect) may be or may comprise a second peer wireless device.

The at least one secondary path of the DC (e.g., according to the first method aspect) may be wirelessly connected towards the second peer wireless device using at least one of a second SL and a PC5 interface between the wireless device and the second peer wireless device.

The first peer wireless device (e.g according to the first method aspect) may be a relay wireless device relaying the first path of the DC from the wireless device to the second peer wireless device. The second peer wireless device may be or may comprise both a master node and a secondary node of the DC of the wireless device. The first peer wireless device (e.g., according to the first method aspect) may be a relay wireless device relaying the first path of the DC from the wireless device to at least one further wireless device other than the second peer wireless device.

The at least one further wireless device (e.g., according to the first method aspect) may be or may comprise a master node of the DC of the wireless device. The second peer wireless device may be or may comprise at least one secondary node of the DC of the wireless device.

The at least one further wireless device (e.g., according to the first method aspect) may be or may comprise a secondary node of the DC of the wireless device. The second peer wireless device may be or may comprise at least one master node of the DC of the wireless device.

The method (e.g., according to the first method aspect) wherein a wireless ad hoc network may comprise at least one of the wireless device, the first peer wireless device and the at least one station.

The wireless connection of the first path from the wireless device towards the first peer wireless device using the first SL between the wireless device and the first peer wireless device (e.g., according to the first method aspect) may be a master link of the DC of the wireless device. The wireless connection of the at least one secondary path from the wireless device towards the at least one station may be a secondary link of the DC of the wireless device.

The wireless connection of the first path from the wireless device towards the first peer wireless device using the first SL between the wireless device and the first peer wireless device (e.g., according to the first method aspect) may be a secondary link of the DC of the wireless device. The wireless connection of the at least one secondary path from the wireless device towards the at least one station may be a master link of the DC of the wireless device.

Both the first path and the at least one secondary path (e.g., according to the first method aspect) may carry a radio bearer (RB) that is anchored at an entity of an anchoring layer, optionally an anchoring layer of the master node or the secondary node. The anchoring layer (e.g according to the first method aspect) may comprise at least one of a medium access control (MAC) layer; a radio link control (RLC) layer; a packet data convergence protocol (PDCP) layer; a radio resource control (RRC) layer; and a service data adaptation protocol (SDAP) layer.

The bearer (e.g according to the first method aspect) may be at least one of split and duplicated at a split layer below the anchoring layer.

The split layer (e.g according to the first method aspect) may comprise at least one of a physical (PHY) layer; a medium access control (MAC) layer; a radio link control (RLC) layer; a packet data convergence protocol (PDCP) layer; and a radio resource control (RRC) layer.

The bearer (e.g according to the first method aspect) may be a split bearer anchored at a PDCP entity associated with one or two Unacknowledged Mode (UM) RLC entities for the first path and associated with one or two UM RLC entities for the at least one secondary path.

The bearer (e.g according to the first method aspect) may be a split bearer anchored at a PDCP entity associated with one Acknowledged Mode (AM) RLC entities for the first path and associated with one AM RLC entities for the at least one secondary path.

The bearer (e.g according to the first method aspect) may be configured for the duplication at a PDCP entity associated with N or IN UM RLC entities for the first path and associated with N or IN UM RLC entities for the at least one secondary path.

The bearer (e.g according to the first method aspect) may be configured for the duplication at a PDCP entity associated with N AM RLC entities for the first path and associated with N AM RLC entities for the at least one secondary path.

The first path (e.g according to the first method aspect) may carry a first non-split RB. Alternatively or in addition, the at least one secondary path may carry a second non-split RB. A first non-split RB (e.g., according to the first method aspect) mapped to the first path may be associated with a first PDCP entity and one or two first UM RLC entities or one first AM RLC entity, and/or wherein a second non-split RB mapped to the at least one secondary path may be associated with a second PDCP entity and one or two second UM RLC entities or one second AM RLC entity.

The at least one packet (e.g., according to the first method aspect) may be transmitted from the wireless device to the first peer wireless device in the first path of the DC.

The at least one packet (e.g., according to the first method aspect) may be transmitted from the wireless device to the at least one station in the at least one secondary path of the DC.

The DC (e.g., according to the first method aspect) may be a multi-connectivity comprising more than two paths.

Herein, the DC may be a multi-connectivity. For example, the at least one secondary path may comprise two or more secondary paths.

The at least one or each of the steps of transmitting (e.g., according to the first method aspect) may be performed according to at least one of the following duplication conditions:

- according to a duplication condition that depends on, or is controlled, by at least one of a service using the DC, an application using the DC, and a traffic transmitted using the DC;

- in predefined or configured geographical location;

- when a level of a QoS of data pending for the transmission at the wireless device is greater than a predefined or configured threshold value;

- when a signal strength of one or each of the at least one network node at the Uu interface is less than a predefined or configured threshold value;

- upon an indication and/or configuration from the at least one network node or the wireless access network;

- upon an indication and/or configuration from the peer wireless device;

- upon an indication from an upper layer of a communication protocol stack at the wireless device; and - upon an indication received from a host computer of an application and/or service used at the wireless device.

The wireless device (e.g., according to the first method aspect) may select whether to activate the duplication on one, a portion, or all of the paths, optionally every time that a packet for transmission becomes available at the wireless device.

Each of the at least one packet received over the at least one secondary path (e.g., according to the second method aspect) may be a duplication of each of the at least one packet received over the first path.

All except one of the received at least one packet of the duplicated packets may be discarded.

The method (e.g., according to the second method aspect) may further comprise or initiate the step of incrementing a counter for each of the received at least one packet if the respective packet is indicative that the respective packet is a duplicated packet or that the duplication is activated.

The counter may be a counter at the intermediate node or destination node (i.e., target node or receiving node) performing the method. Alternatively or in addition, the counter may be initialized to zero.

The method (e.g., according to the second method aspect), wherein such a counter may be maintained for each of service or service ID, and/or for each traffic or traffic ID, and/or for each QoS or QoS ID, and/or for each packet ID, and/or for each source node or source node ID, and/or for each destination node or destination node ID.

The step of discarding (e.g., according to the second method aspect) may comprise checking if two or more packets have been received, which are indicative of, or which belong to, the same service or service ID, and/or the same traffic or traffic ID, and/or the same QoS or QoS ID, and/or the same packet ID, and/or the same source node or source node ID, and/or the same destination node or destination node ID.

The checking may use the respective counter. The step of discarding (e.g., according to the second method aspect) may comprise discarding all except one of the two or more packets per service or service ID, and/or per traffic or traffic ID, and/or per QoS or QoS ID, and/or per packet ID, and/or per source node or source node ID, and/or per destination node or destination node ID.

The step of discarding (e.g., according to the second method aspect) may comprise upon receiving of each of the at least one packet, discarding the respective packet if another packet has been previously received which is indicative of or which belongs to the same service or service ID, and/or the same traffic or traffic ID, and/or the same QoS or QoS ID, and/or the same packet ID, and/or the same source node or source node ID, and/or the same destination node or destination node ID.

Upon receiving multiple packets at the same time, the step of discarding 404 (e.g., according to the second method aspect) may comprise at least one of: keeping only the first received packet and discarding the other received packets among the multiple packets; keeping only the last received packet and discarding the other received packets among the multiple packets; keeping only the packet transmitted or generated first among the multiple packets, optionally according to a packet time stamp of the respective one of the multiple packets, and discarding the other received packets among the multiple packets; keeping only the packet transmitted or generated last among the multiple packets, optionally according to a packet time stamp of the respective one of the multiple packets, and discarding the other received packets among the multiple packets; keeping only the packet indicative of a packet SN equal to 0 or 1, and discarding the other received packets among the multiple packets; keeping only the packet indicative of being the first packet transmitted by the source node among the multiple packets, and discarding the other received packets among the multiple packets; and keeping only the packet indicative of being the last packet transmitted by the source node among the multiple packets, and discarding the other received packets among the multiple packets.

The multiple packets may be received at the destination node. The method 400 (e.g., according to the second method aspect) may be performed by the at least one station or the first peer wireless device.

The method 400 (e.g., according to the second method aspect) may be performed by an intermediate node of the first path or the at least one secondary path. Alternatively or in addition, the method may be performed by the destination node of the transmission or of the first path or of the at least one secondary path.

The method 400 may further comprise the features of any steps of the method 300, or any feature or step corresponding thereto.

The node 200, 210, and/or 220 may be an intermediate node or a destination node. Alternatively or in addition, the node 200, 210, and/or 220 may be a node of the first path or a node of the at least one secondary path.

The node 200, 210, and/or 220 may further comprise any feature, or may be operable to perform any step, of the method 400.

In any aspect, the technique may use an uplink (UL) and/or downlink (DL) in the at least one secondary path and/or direct communications between radio devices, e.g., device-to-device (D2D) communications or sidelink (SL) communications in the first path.

Each of the wireless device 100 and network node 220 may be a radio device and a base station, respectively. Herein, any wireless device (e.g., radio device) may be a mobile or portable station and/or any radio device wirelessly connectable to a base station or RAN, or to another radio device. For example, the radio device may be a user equipment (UE), a device for machine-type communication (MTC) or a device for (e.g., narrowband) Internet of Things (loT). Two or more radio devices may be configured to wirelessly connect to each other, e.g., in an ad hoc radio network or via a 3GPP SL connection. Furthermore, any base station may be a station providing radio access, may be part of a radio access network (RAN) and/or may be a node connected to the RAN for controlling the radio access. For example, the base station may be an access point, for example a Wi-Fi access point.

Embodiments of the technique may use packet duplication (or briefly: duplication, i.e., duplication of the same packet), e.g., on high frequencies. Same or further embodiments can discard multiple duplicates of the same packet by a certain node. The technique may be not limited to discarding only two duplicates, e.g., as in existing systems it is only possible for a UE to have only two connections active at the same time.

At least some embodiments enable discarding even if a packet data convergence protocol (PDCP) entity is not able to communicate with all the radio link control (RLC) entities for which the duplication has been activated, which may be the case e.g., when the duplication is applied by using both Uu and PC5 since in this case there could be different PDCP entities hosted in different nodes.

At least some embodiments may be applied where an existing mechanism of PDCP duplication in DC using the Uu interface cannot be directly applied for the DC (e.g., multi-connectivity or MC) when at least one path, i.e. the first path, involves a SL. As a first example, the first path may comprise at least 2 hops, meaning that a network node (e.g., the at least one station and/or a gNB) or the wireless device (e.g., a UE) cannot send existing control signaling (such as a MAC CE) to control when to activate or deactivate the duplication. As a second example, the first SL path may comprise at least 2 hops, meaning that there may be redundant packet duplicates remain in an intermediate node in the first path SL so that a network node (e.g., the at least one station and/or a gNB) or the wireless device (e.g., a UE) cannot use existing control signaling to contact the at least one intermediate node (e.g., directly) for discarding (e.g., clearing) the redundant packet duplicates.

Embodiments of the technique can enable multi-path links (i.e., the paths) in case of DC (e.g., multi-connectivity) scenarios. Same or further embodiments may comprise use at least one sidelink (e.g., a wireless device-to-device, or D2D, communication) for dual connectivity, e.g., for a wireless transmission on multiple paths and/or over multiple hops. Same or further embodiments may use a radio access technology for the paths according to 3GPP New Radio (NR) and/or 3GPP Long Term Evolution (LTE).

The technique may be applied in the context of 3GPP NR. Alternatively or in addition, the technique may be implemented in accordance with, or by extending, a 3GPP specification, e.g., for 3GPP release 16 or 17, e.g., the 3GPP document TS 38.331, version 16.5.0; and/or the 3GPP document TS 38.323, version 16.4; and/or the 3GPP document TS 38.300, version 16.6.0. Alternatively or in addition, the technique may be implemented for 3GPP LTE or 3GPP NR according to a modification of the 3GPP document TS 23.303, version 16.0.0 or for 3GPP NR according to a modification of the 3GPP document TS 33.303, version 16.0.0.

In any radio access technology (RAT), the technique may implement DC using a relay over the SL. The SL may be implemented using proximity services (ProSe), e.g. according to a 3GPP specification.

Any wireless device may be a radio device, e.g., a user equipment (UE), e.g., according to a 3GPP specification. The relay wireless device may also be referred to as a relay UE (or briefly: relay). Alternatively or in addition, a remote wireless device or remote radio device may also be referred to as a remote UE.

The wireless device, the first peer wireless device, the second peer wireless device, the at least one network node, the at least on further network node, and/or the wireless access network (e.g., RAN) may form, or may be part of, a wireless (e.g., radio) network, e.g., according to the Third Generation Partnership Project (3GPP) or according to the standard family IEEE 802.11 (Wi-Fi). The first method aspect, the second method aspect may be performed by one or more embodiments of the wireless device and the RAN (e.g., a serving network node or a base station of the wireless device), respectively.

The RAN may comprise one or more network node (e.g., base stations), e.g., performing the second method aspect. Alternatively or in addition, the radio network may be a vehicular, ad hoc and/or mesh network comprising two or more wireless device (e.g., radio devices), e.g., acting the wireless device and/or the first peer wireless device and/or the second peer wireless device and/or a further wireless device.

Any of the wireless devices (e.g., radio devices) may be a 3GPP user equipment (UE) or a Wi-Fi station (STA). Any wireless device may be a mobile or portable station, a device for machine-type communication (MTC), a device for narrowband Internet of Things (NB-loT) or a combination thereof. Examples for the UE and the mobile station include a mobile phone, a tablet computer and a self-driving vehicle. Examples for the portable station include a laptop computer and a television set. Examples for the MTC device or the NB-loT device include robots, sensors and/or actuators, e.g., in manufacturing, automotive communication and home automation. The MTC device or the NB-loT device may be implemented in a manufacturing plant, household appliances and consumer electronics.

Whenever referring to the RAN, the RAN may be implemented by one or more network node (e.g., base stations).

The wireless device may be wirelessly connected or connectable (e.g., according to a radio resource control, RRC, state or active mode) with the relay wireless device and/or at least one base station of the RAN. The relay radio device may be wirelessly connected or connectable (e.g., according to a radio resource control, RRC, state or active mode) with at least one base station of the RAN and/or the further remote radio device. Furthermore, the relay radio device may be wirelessly connected or connectable (e.g., according to 3GPP ProSe) with the remote radio device.

Any network node (e.g., base station) may encompass a station that is configured to provide wireless (e.g., radio access) to any of the wireless device (e.g., radio devices). Any of the network nodes may also be referred to or implemented by a base station, cell, a transmission and reception point (TRP), a radio access node or access point (AP). The base station and/or the relay radio device may provide a data link to a host computer providing the user data to the remote radio device or gathering user data from the remote radio device.

Examples for the network nodes (e.g., base stations) may include a 3G base station or Node B, 4G base station or eNodeB, a 5G base station or gNodeB, a Wi-Fi AP and a network controller (e.g., according to Bluetooth, ZigBee or Z-Wave).

The RAN may be implemented according to the Global System for Mobile Communications (GSM), the Universal Mobile Telecommunications System (UMTS), 3GPP Long Term Evolution (LTE) and/or 3GPP New Radio (NR).

Any aspect of the technique may be implemented on a Physical Layer (PHY), a Medium Access Control (MAC) layer, a Radio Link Control (RLC) layer, a packet data convergence protocol (PDCP) layer, and/or a Radio Resource Control (RRC) layer of a protocol stack for the radio communication. Herein, referring to a protocol of a layer may also refer to the corresponding layer in the protocol stack. Vice versa, referring to a layer of the protocol stack may also refer to the corresponding protocol of the layer. Any protocol may be implemented by a corresponding method.

Herein, whenever referring to noise or a signal-to-noise ratio (SNR), a corresponding step, feature or effect is also disclosed for noise and/or interference or a signal-to-interference-and-noise ratio (SINR).

Alternatively or in addition to any embodiment disclosed herein, the technique may enable a node (i.e., network node, or a UE) to discard duplicated packets, when such duplicated packets are more than two. In order to do this, at least (or a combination) or one of the following features and/or steps may be applied:

The node (e.g., the device 100) that decides to apply duplication for a certain traffic/service it includes in each duplicate packets to be transmitted additional information as follows: o An indication on whether this packet is transmitted with duplication active (or not) o The total number of the duplicates generated for a given packet o The packet ID o The packet sequence number (SN) o Whether this is the first packet to be transmitted (out of all the duplicates) o Whether this is the last packet transmitted (out of all the duplicates) o Time stamp on when the packet has been sent by the source node o Traffic ID and/or service ID and/or QoS ID o Source node ID o Destination node ID

Alternatively or in addition, the node (e.g., the device 100) that decides to apply duplication for a certain traffic/service may perform the following actions: o sends a packet over a first duplicated path and if no acknowledgment is received that the packets has been received, the node decide to send a duplicate of the same packet over another available path (different from the previous one), and so on until an acknowledgement is received that the packets has been received. If no acknowledgement is received on any of the available path (i.e., thus for any of the duplicated packets), the node stops transmissions and releases all the paths o Sends a duplicated packet on each of the available paths at the same time and then starts a timer. If no acknowledgment is received by the expiring of the timer from any of the available paths, the node stops transmissions and releases all the paths. Alternatively, if by expiring of the timer the node receives an acknowledgment on some of the paths, the node may keep sending (duplicate) packets on those paths and releases all the path for which an acknowledgement was not received o Sends duplicate packets on each of the available path at the same time and then start a timer. The UE will continue sending duplicate packets at periodic interval or based on some triggering conditions over all the available path until the timer does not expire. In such a case, the sending of the duplicate packets will continue until the timer expires regardless of whether an acknowledgment is received on not on one or more paths. o Sends duplicate packets on each of the available path at the same time. After the first acknowledgment is received on one of the available path, the UE stops sending duplicates over the other path and use only the path on which the first acknowledgement has been received (with no duplication of packets).

Further, the receiving node (e.g., the node 210 or 220, particularly a network node or a UE) that receive duplicates packets according to the method 400 (which may be in an intermediate node or the node that is the destination of the traffic and/or service) may perform at least one of the following actions: - After receiving the first packet, the receiving node checks whether this packet is using duplication and if it does, it increments an internal counter (that is initialized by default to zero). Every time that there are other packets belonging to the same service/traffic/QoS that are received and that use duplication, the receiving node discard them is the counter is greater than 1. This of course imply that the UE needs to keep a different counter for each service/traffic/QoS.

- After receiving a packet, the UE checks if other packets with the same source and destination ID for a given type of traffic has been received. If duplication has been used, the receiving node discards this packet if another one has been previously received.

- If multiple duplicated packets are received at the same time by the receiving node, the receiving node may keep one packets and discard the other ones according to the following criteria: o The receiving UE keeps only the first received packet and discards the others. o The receiving UE keeps only the last received packet and discards the others. o The receiving UE keeps only the first packet generated by the source UE (according to the packet time stamps) and discards the others. o The receiving UE keeps only the last packet generated by the source UE (according to the packet time stamps) and discards the others. o The receiving UE keeps only the packet with sequence number (SN) equal to 1 (or 0, depending on which is the initial value) and discards the others. o The receiving UE keeps only the packet marked as "first packet transmitted" by the source node and discards the others. o The receiving UE keeps only the packet marked as "last packet transmitted" by the source node and discards the others.

Fig. 5 schematically illustrates a wireless access network or an ad hoc network comprising an embodiments of the first peer wireless device 210 in coverage or out of coverage of a cell 502 of an embodiment of a network node 220.

Any of the embodiments may implement 3GPP Dual Connectivity (DC) according to any one of the options describe below. There are different ways to deploy 5G network 500 with or without interworking with LTE (also referred to as E-UTRA) and evolved packet core (EPC), e.g., as depicted in Fig. 6.

In principle, NR and LTE can be deployed without any interworking, denoted by NR stand-alone (SA) operation, that is gNB in NR can be connected to 5G core network (5GC) and eNB can be connected to EPC with no interconnection between the two (Option 1 and Option 2 in the figure). On the other hand, the first supported version of NR is the so-called EN-DC (E-UTRAN-NR Dual Connectivity), illustrated by Option 3. In such a deployment, dual connectivity between NR and LTE is applied with LTE as the master and NR as the secondary node. The RAN node (gNB) supporting NR, may not have a control plane connection to core network (EPC), instead it relies on the LTE as master node (MeNB). This is also called as "Non-standalone NR". Notice that in this case the functionality of an NR cell is limited and would be used for connected mode UEs as a booster and/or diversity leg, but an RRCJDLE UE cannot camp on these NR cells.

With introduction of 5GC, other options may be also valid. As mentioned above, Option 2 supports stand-alone NR deployment where gNB is connected to 5GC. Similarly, LTE can also be connected to 5GC using Option 5 (also known as eLTE, E-UTRA/5GC, or LTE/5GC and the node can be referred to as an ng-eNB). In these cases, both NR and LTE are seen as part of the NG-RAN (and both the ng-eNB and the gNB can be referred to as NG-RAN nodes). It is worth noting that, Option 4 and Option 7 are other variants of dual connectivity between LTE and NR which will be standardized as part of NG-RAN connected to 5GC, denoted by MR-DC (Multi-Radio Dual Connectivity).

Under the MR-DC umbrella, the technique may implement at least one of:

EN-DC (Option 3): LTE is the master node and NR is the secondary (EPC CN employed).

NE-DC (Option 4): NR is the master node and LTE is the secondary (5GCN employed).

NGEN-DC (Option 7): LTE is the master node and NR is the secondary (5GCN employed). NR-DC (variant of Option 2): Dual connectivity where both the master and secondary are NR (5GCN employed).

Fig. 6 schematically illustrates LTE and NR interworking options, which may be implemented by the technique.

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

LTE DC and multi-RAT DC (MR-DC) are designed differently when it comes to which nodes control what. Basically, there are two options:

1. Centralized solution, e.g., LTE-DC),

2. Decentralized solution, e.g., MR-DC, i.e. (NG)EN-DC, NE-DC and NR-DC).

Fig. 7 shows a schematic control plane architecture, e.g., for LTE DC and EN-DC. Note that the EN-DC architecture also applies to other MR-DC options. The main difference here is that in EN-DC, a secondary node (SN) has a separate RRC entity (NR RRC). This means that the SN can control the UE also; sometimes without the knowledge of the MN but often the SN need to coordinate with the MN. In LTE- DC, the RRC decisions are always coming from the MN (MN to UE). Note however, the SN still decides the configuration of the SN, since it is only the SN itself that has knowledge of what kind of resources, capabilities etc. it has.

It is noted that it is clear from the context when SN refers to the secondary node and when SN refers to a packet sequence number.

Any embodiment may implement the Control Plane architecture for Dual Connectivity 1500 in LTE DC and EN-DC according to Fig. 7. EN-DC may differ, e.g., compared to LTE DC, by the introduction of split bearer 800 from the SN (known as SCG split bearer), the introduction of split bearer 800 for RRC, and/or the introduction of a direct RRC from the SN (also referred to as SCG SRB).

Figs. 8 and 9 show the UP and Control Plane (CP) architectures for EN-DC.

In Fig. 8, the network side protocol termination options for MCG, SCG and split bearers in MR-DC with EPC (EN-DC) are schematically illustrated.

In Fig. 9, network architecture for control plane in EN-DC are schematically illustrated.

The SN is sometimes referred to as SgNB (where gNB is an NR base station), and the MN as MeNB in case the LTE is the master node and NR is the secondary node. In the other case where NR is the master and LTE is the secondary node, the corresponding terms are SeNB and MgNB.

Split RRC messages are mainly used for creating diversity, and the sender can decide to either choose one of the links for scheduling the RRC messages, or it can duplicate the message over both links. In the downlink, the path switching between the MCG or SCG legs or duplication on both is left to network implementation. On the other hand, for the UL, the network configures the UE to use the MCG, SCG or both legs. The terms "leg", "path" and "RLC bearer" are used interchangeably throughout this document.

Any of the embodiments may implement the SL (i.e., wireless device-to-device, D2D, communication) according to 3GPP.

3GPP specified the LTE D2D technology, also known as Proximity Services (ProSe) in the Releases 12 and 13 of LTE. Later in Releases 14 and 15, LTE V2X-related enhancements targeting the specific characteristics of vehicular communications were specified. 3GPP has started a new work item (Wl) in August 2018 within the scope of Release 16 to develop a new radio (NR) version of V2X communications. The NR V2X mainly targets advanced V2X services, which can be categorized into four use case groups: vehicles platooning, extended sensors, advanced driving and remote driving. The advanced V2X services would require enhanced NR system and new NR sidelink framework to meet the stringent requirements in terms of latency and reliability. NR V2X system also expects to have higher system capacity and better coverage and to allow for an easy extension to support the future development of further advanced V2X services and other services.

Given the targeted services by NR V2X, it is commonly recognized that groupcast/multicast and unicast transmissions are desired, in which the intended receiver of a message consists of only a subset of the vehicles in proximity to the transmitter (groupcast) or of a single vehicle (unicast). For example, in the platooning service there are certain messages that are only of interest of the members of the platoon, making the members of the platoon a natural groupcast. In another example, the see-through use case most likely involves only a pair of vehicles, for which unicast transmissions naturally fit. Therefore, NR sidelink can support broadcast (as in LTE), groupcast and unicast transmissions. Furthermore, NR sidelink is designed in such a way that its operation is possible with and without network coverage and with varying degrees of interaction between the UEs and the network (NW), including support for standalone, network-less operation.

National Security and Public Safety (NSPS) is considered to be one of the use cases of the technique, e.g., in the context of In 3GPP Release 17, which can benefit from the already developed NR SL. For example, 3GPP may specify enhancements related to NSPS use case taking NR Release 16 sidelink as a baseline.

Any embodiment may serve National Security and Public Safety (NSPS) use case and/or requirements.

In the traditional specific NSPS communication systems such as Terrestrial Trunked Radio (TETRA), the data rates were in the order of a few kbit/s at most, which do not provide support for the foreseen NSPS use case scenarios. Moreover, the NSPS use case requires an enhanced coverage and high reliability for its communications. Therefore, NSPS is a particularly interesting case for NR since it can provide the required robustness in the communications and the capability to communicate even in the cases where a fixed infrastructure is not installed. Fig. 10 schematically illustrates a scenario for NSPS including in and out-of- coverage users.

Some of the scenarios where NSPS communication has potentially no support from the infrastructure are such as tunnels, inside some buildings or in emergency situations where the infrastructure is destroyed or non-operative. Even though in some of these cases, cellular coverage can be provided using some sort of mobile stations, i.e., trucks with a portable base station installed as shown in Fig. 10, the implementation of sidelink communications can be beneficial in NSPS. Among the requirements for NSPS, one main topic is the group communication for NSPS in cases such as, a group of workers in a building. The scenarios which are considered for NSPS include in-coverage scenarios where network (eNB/gNB) is available and out-of-coverage scenarios where there is no infrastructure. For the out-of-coverage scenario the addition of sidelink for synchronization and communication among the users is foreseen, however, the inclusion of multi-hop sidelink has not been realized in legacy communication systems.

Any embodiment may use PDCP for packet duplication, e.g., in a NR system.

PDCP layer can provide routing and packet duplication. There is one PDCP entity per radio bearer configured for a device. Moreover, dual connectivity is another feature that is enabled in NR systems due to the PDCP layer.

Packet duplication in PDCP can be used for additional diversity. Packets can be duplicated and transmitted on multiple cells, increasing the likelihood of at least one copy being correctly received. This can be useful for services requiring very high reliability. At the receiving end, the PDCP layer duplicate removal functionality removes any duplicates. This results in path selection diversity.

Dual connectivity is another area where the PDCP layer plays an important role. In dual connectivity, a device is connected to two cells, or in general, two cell groups, the Master Cell Group (MCG) and the Secondary Cell Group (SCG). The two cell groups can be handled by different gNBs. A radio bearer is typically handled by one of the cell groups, but there is also the possibility for split bearers, in which case one radio bearer is handled by both cell groups. In this case the PDCP is in charge of distributing the data between the MCG and the SCG.

The step 404 of discarding may be implemented according to, or as an extension of duplicate PDU discard, e.g., as described below.

For the PDCP entity configured with PDCP duplication, the transmitting PDCP entity may at least one of:

- If the successful delivery of a PDCP Data PDU is confirmed by one of the associated AM RLC entities, indicate to the other AM RLC entities to discard the duplicated PDCP Data PDU.

- If the deactivation of PDCP duplication is indicated for the DRB, indicate to the RLC entities other than the primary RLC entity to discard all duplicated PDCP Data PDUs.

- If the deactivation of PDCP duplication is indicated for at least one associated RLC entities, indicate to the RLC entities deactivated for PDCP duplication to discard all duplicated PDCP Data PDUs.

The step 404 of discarding may use at least one of the parameters (e.g., variables, counters, and/or timers) and/or actions (e.g., modifying the parameters) described below.

The actions may use, e.g., when a PDCP Data PDU is received from lower layers In this clause, at least one of the following definitions:

- HFN(State Variable): the HFN part (i.e. the number of most significant bits equal to HFN length) of the State Variable;

- SN(State Variable): the SN part (i.e. the number of least significant bits equal to PDCP SN length) of the State Variable;

- RCVD_SN: the PDCP SN of the received PDCP Data PDU, included in the PDU header;

- RCVD_HFN: the HFN of the received PDCP Data PDU, calculated by the receiving PDCP entity;

- RCVD_COUNT: the COUNT of the received PDCP Data PDU = [RCVD_HFN, RCVD_SN] At reception of a PDCP Data PDU from lower layers, the receiving PDCP entity may determine the COUNT value of the received PDCP Data PDU, i.e. RCVD_COUNT, as follows:

- if RCVD_SN < SN(RX_DELIV) - Window_Size: - RCVD_HFN = HFN(RX_DELIV) + 1.

- else if RCVD_SN >= SN(RX_DELIV) + Window_Size:

- RCVD_HFN = HFN(RX_DELIV) - 1.

- else:

- RCVD_HFN = HFN(RX_DELIV); - RCVD_COUNT = [RCVD_HFN, RCVD_SN].

After determining the COUNT value of the received PDCP Data PDU = RCVD_COUNT, the receiving PDCP entity may at least one of:

- perform deciphering and integrity verification of the PDCP Data PDU using COUNT = RCVD_COUNT; - if integrity verification fails:

- indicate the integrity verification failure to upper layer;

- discard the PDCP Data PDU and consider it as not received;

- if RCVD_COUNT < RX_DELIV; or

- if the PDCP Data PDU with COUNT = RCVD_COUNT has been received before: - discard the PDCP Data PDU;

If the received PDCP Data PDU with COUNT value = RCVD_COUNT is not discarded above, the receiving PDCP entity may at least one of:

- store the resulting PDCP SDU in the reception buffer;

- if RCVD_COU NT >= RX_N EXT: - update RX_N EXT to RCVD_COUNT + 1.

- if outOfOrderDelivery is configured:

- deliver the resulting PDCP SDU to upper layers after performing header decompression using EHC.

- if RCVD COUNT = RX DELIV: deliver to upper layers in ascending order of the associated COUNT value after performing header decompression, if not decompressed before;

- all stored PDCP SDU(s) with consecutively associated COUNT value(s) starting from COUNT = RX_DELIV;

- update RX_DELIV to the COUNT value of the first PDCP SDU which has not been delivered to upper layers, with COUNT value > RX_DELIV;

- if t-Reordering is running, and if RX_DELIV >= RX_REORD:

- stop and reset t-Reordering.

- if t-Reordering is not running (includes the case when t-Reordering is stopped due to actions above), and RX_DELIV < RX_NEXT:

- update RX_REORD to RX_NEXT;

- start t-Reordering.

Any embodiment may implement a Radio-Link Control, e.g., in a NR system.

Radio-Link Control (RLC) is responsible for segmentation and retransmission handling. The RLC provides services to the PDCP in the form of RLC channels. There is one RLC entity per RLC channel (and hence per radio bearer) configured for a device. Compared to LTE, the NR RLC does not support in-sequence delivery of data to higher protocol layers, a change motivated by the reduced delays. The RLC protocol is responsible for segmentation of RLC SDUs from the PDCP into suitably sized RLC PDUs. It also handles retransmission of erroneously received PDUs, as well as removal of duplicate PDUs.

Depending on the type of service, the RLC can be configured in one of three modes— transparent mode, unacknowledged mode, and acknowledged mode — to perform some or all these functions. Transparent mode adds no headers to the transmissions. Unacknowledged mode supports segmentation and duplicate detection, while acknowledged mode in addition to the latter supports retransmission of erroneous packets.

One major difference compared to LTE is that the RLC does not ensure in sequence delivery of SDUs to upper layers. Removing in-sequence delivery from the RLC reduces the overall latency as later packets do not have to wait for retransmission of an earlier missing packet before being delivered to higher layers but can be forwarded immediately. Another difference is the removal of concatenation from the RLC protocol to allow RLC PDUs to be assembled in advance, prior to receiving the uplink scheduling grant. This also helps reduce the overall latency.

Any embodiment using a relay at the first peer wireless device 210 may implement a Layer 2 (L2) UE-to-Network relay.

In the TR 23.752 clause 6.7, the layer-2 based UE-to-Network relay is described. The protocol architecture supporting a L2 UE-to-Network Relay UE is provided. The L2 UE-to-Network Relay UE provides forwarding functionality that can relay any type of traffic over the PC5 link.

The L2 UE-to-Network Relay UE provides the functionality to support connectivity to the 5GS for Remote UEs. A UE is considered to be a Remote UE if it has successfully established a PC5 link to the L2 UE-to-Network Relay UE. A Remote UE can be located within NG-RAN coverage or outside of NG-RAN coverage.

Fig. 11 illustrates the protocol stack for the user plane transport, related to a PDU Session, including a Layer 2 UE-to-Network Relay UE. The PDU layer corresponds to the PDU carried between the Remote UE and the Data Network (DN) over the PDU session. The PDU layer corresponds to the PDU carried between the Remote UE and the Data Network (DN) over the PDU session. It is important to note that the two endpoints of the PDCP link are the Remote UE and the gNB. The relay function is performed below PDCP. This means that data security is ensured between the Remote UE and the gNB without exposing raw data at the UE-to- Network Relay UE.

Fig. 11 schematically illustrates a User Plane Stack for L2 UE-to-Network Relay UE in TR 23.752.

The adaptation rely layer within the UE-to-Network Relay UE can differentiate between signaling radio bearers (SRBs) and data radio bearers (DRBs) for a particular Remote UE. The adaption relay layer is also responsible for mapping PC5 traffic to one or more DRBs of the Uu. The definition of the adaptation relay layer is under the responsibility of RAN WG2. Fig. 12 schematically illustrates the protocol stack of the NAS connection for the Remote UE to the NAS-MM and NAS-SM components. The NAS messages are transparently transferred between the Remote UE and 5G-AN over the Layer 2 UE-to-Network Relay UE using at least one of:

- PDCP end-to-end connection where the role of the UE-to-Network Relay UE is to relay the PDUs over the signaling radio bear without any modifications.

- N2 connection between the 5G-AN and AMF over N2.

- Nil connection AMF and SMF over Nil.

The role of the UE-to-Network Relay UE is to relay the PDUs from the signaling radio bearer without any modifications.

Fig. 12 schematically illustrates a Control Plane for L2 UE-to-Network Relay UE in TR 23.752

Alternatively or in addition, any embodiment using a relay at the first peer wireless device 210 may implement Layer 3 (L3) UE-to-Network relay.

E.g., in the 3GPP document TR 23.752, clause 6.6, the layer-3 based UE-to- Network relay is described.

The ProSe 5G UE-to-Network Relay entity provides the functionality to support connectivity to the network for Remote UEs (see Fig. 13). It can be used for both public safety services and commercial services (e.g. interactive service).

A UE is considered to be a Remote UE for a certain ProSe UE-to-Network relay if it has successfully established a PC5 link to this ProSe 5G UE-to-Network Relay. A Remote UE can be located within NG-RAN coverage or outside of NG-RAN coverage.

Fig. 13 schematically illustrates an architecture model using a ProSe 5G UE-to- Network Relay according to the 3GPP document TR 23.752.

The ProSe 5G UE-to-Network Relay shall relay unicast traffic (UL and DL) between the Remote UE and the network. The ProSe UE-to-Network Relay shall provide generic function that can relay any IP traffic. One-to-one Direct Communication is used between Remote UEs and ProSe 5G UE-to-Network Relays for unicast traffic as specified in solutions for Key Issue #2 in the TR 23.752.

The protocol stack for Layer-3 UE-to-Network Relays is shown in Figure 5.

Fig. 14 schematically illustrates a protocol stack for ProSe 5G UE-to-Network Relay according to the 3GPP document TR 23.752.

Hop-by-hop security is supported in the PC5 link and Uu link. If there are requirements beyond hop-by-hop security for protection of Remote UE's traffic, security over IP layer needs to be applied.

The technique may enable dual connectivity (e.g., multi connectivity in some cases) between sidelink and Uu link, and also between only sidelink links.

Alternatively or in addition to the embodiments in the list of embodiments, the UE (as the wireless device 100) may have at least one of the following features.

A UE with sidelink capabilities (e.g., transmitting on a standalone sidelink and/or having access to a sidelink relay or acting as a sidelink relay) establishes a dual connectivity connection with one path of the dual connectivity connected towards the network (via Uu) directly and the other path of the dual connectivity connected towards a peer UE (via PC5).

In such a case, the connection with the peer UE may be standalone sidelink (e.g., if the peer UE is the destination of the traffic) or may be sidelink relay (e.g., if the destination of the traffic is the gNB or another UE that is reachable via the peer UE).

A UE with sidelink capabilities (i.e., standalone sidelink and/or sidelink relay) establishes a dual connectivity connection with one path (i.e., the at least one secondary path) of the dual connectivity connected towards a UE (e.g., a second peer UE and/or via PC5 link, e.g. labeled "1") and the other path (i.e., the first path) of the dual connectivity connected towards a peer UE (e.g., the first peer UE and/or via a PC5 link, e.g. labeled "2").

In such a case, the connection with the peer UEs may be standalone sidelink (e.g., if the peer UE is the destination of the traffic) or may be sidelink relay (e.g., if the destination of the traffic is the gNB or another UE that is reachable via the peer UE).

A UE with also sidelink capabilities (i.e., standalone sidelink and/or sidelink relay) establishes as many multiple connections as it supports (based on its capabilities). These multiple connections can be established towards one, or more peer UEs and one, or more, cell groups (e.g., MCG, SCG).

In any embodiment, the establishing steps 302 and 304 may be triggered upon an indication and/or configuration, e.g., from a peer UE 210.

In this disclosure, the term node is used which can be a network node or a UE.

Examples of network nodes are NodeB, base station (BS), multi-standard radio (MSR) radio node such as MSR BS, eNodeB, gNodeB. MeNB, SeNB, integrated access backhaul (IAB) node, network controller, radio network controller (RNC), base station controller (BSC), relay, donor node controlling relay, base transceiver station (BTS), Central Unit (e.g. in a gNB), Distributed Unit (e.g. in a gNB), Baseband Unit, Centralized Baseband, C-RAN, access point (AP), transmission points, transmission nodes, RRU, RRH, nodes in distributed antenna system (DAS), core network node (e.g. MSC, MME etc.), O&M, OSS, SON, positioning node (e.g. E-SMLC), etc.

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

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

The term radio access technology (RAT) may refer to any RAT, e.g. UTRA, E-UTRA, narrow band internet of things (NB-loT), Wi-Fi, Bluetooth, next generation RAT, New Radio (NR), 4G, 5G, etc. Any of the equipment denoted by the terminology node, network node or radio network node may be capable of supporting a single or multiple RATs.

Further, in the following we use the term "standalone sidelink" to describe a sidelink connection that is just between a UE (e.g., UE1) and a peer UE (i.e., UE2) and where the peer UE (i.e., UE2) is the destination of the traffic. On the contrary, we use the term "sidelink relay" to describe a sidelink connection between a source UE (i.e., the remote UE - RM UE) and a destination UE/gNB and which communication happens via an intermediate UE (i.e., the relay UE - RL UE).

Finally, in the following the term DC for dual connectivity may relate to a scenario where the UE 100 has at least two active links at the same time. According to this, the dual connectivity may happen e.g. on the PDCP entity, or on the RLC entity. If the dual connectivity happens at the RLC entity, then the term "dual connectivity" can be exchanged without loss of meaning with "carrier aggregation". In the following, we use the term "dual connectivity" to describe both the "dual connectivity" at the PDCP entity and the "carrier aggregation" at the RLC entity.

Optionally, the term "direct path" may refer to a direct connection from a remote UE to a gNB (e.g., via NR air interface) or a destination UE (e.g., via NR SL air interface) and we use the term "indirect path" to stand for an indirect connection between a remote UE and a gNB or another destination UE via an intermediate node also known as relay UE or relay gNB.

Alternatively or in addition to the list of embodiments, the wireless device 100 (described as the UE 100 herein) and/or any other node (e.g., the network node 220) may comprise the features of any one of the following detailed embodiments and/or other detailed embodiments.

In a first detailed embodiment, the node (e.g., the wireless device 100) that decides to apply duplication for a certain traffic and/or service, when duplicating the packets and sending (i.e., transmitting according to the step 302 and/or 304) them over the available paths 1510 and/or 1520 (e.g., links and/or connections), performs at least one (e.g., a combination) of the following options:

Option 1. Transmit 302 or 304 a packet over a first path (e.g., the path 1510 or 1520) and if no acknowledgment is received that the packets has been received, the node decide to transmit a duplicate of the packet over another available path (different from the previous one), optionally and so on until an acknowledgement is received that the packets has been received.

If no acknowledgement is received on any of the available path (i.e., thus for any of the duplicated packets), the node stops transmissions and releases all the paths.

Option 2. Transmit 302 and 304 a duplicated packet on each of the available paths 1510 and 1520 at the same time and then start a timer.

If no acknowledgment is received by the expiring of the timer from any of the available paths, the node stops transmissions and releases all the paths.

Alternatively or in addition, if by expiring of the timer, the node 100 receives an acknowledgment on some of the paths, the node 100 may keep sending (duplicate) packets on those paths 1510 and/or 1520 and releases all the path 1510 and/or 1520 for which an acknowledgement was not received.

Option 3. Transmit duplicate packets on each of the available paths 1510 and 1520 at the same time and then start a timer. The UE 100 will continue sending duplicate packets at periodic interval or based on some triggering conditions over all the available paths. In such a case, the transmitting 302 and/or 304 of the duplicate packets will continue until the timer expires, e.g., regardless of whether an acknowledgment is received on not on one or more paths 1510 and/or 1520.

Option 4. Transmit 302 and 304 duplicate packets on each of the available paths 1510 and 1520 at the same time. After the first acknowledgment is received on one of the available paths, the UE 100 stops sending duplicates over the other paths and use only the path on which the first acknowledgement has been received (e.g., with no duplication of packets).

As an additional embodiment or variant of any embodiment, the UE 100 determines to release a path 1510 and/or 1520, which is used for transmission of duplicated packets if at least one of the following releasing conditions is fulfilled.

A first releasing condition is a configured maximum number of duplicated transmissions for one or multiple source packets has been transmitted on the respective path (e.g., the first path 1510 or the at least one secondary path 1520). Alternatively or in addition, there is not any acknowledgement received by the UE on the respective path.

A second releasing condition is a configured time period for transmitting duplicates of for one or multiple source packets is expired. Alternatively or in addition, there is not any acknowledgement received by the wireless device 100 on the respective path.

In a second detailed embodiment, when the source UE decides to use packet duplication in a multi-connectivity scenario, the source UE includes in each packet that is duplicated and transmitted at least (or a combination) of one of the following information:

- An indication on whether this packet is transmitted with duplication active (or not).

- The total number of the duplicates generated for a given packet

- The packet ID

- The packet sequence number (SN)

- Whether this is the first packet to be transmitted (out of all the duplicates)

- Whether this is the last packet transmitted (out of all the duplicates) - Time stamp on when the packet has been sent by the source node.

- Time stamp on when the packet has been generated by the source node.

- Traffic ID and/or service ID and/or QoS ID

- Source node ID

- Destination node ID.

In a third detailed embodiment, the receiving node (e.g., a network node 220 or 222 or a UE 210) that receives duplicates packets according to the method 400 (e.g., an intermediate node or the node that is the destination of the traffic and/or service) discards the duplicated packets according to the step 404, optionally according to at least one (e.g., a combination) of the following options:

Option 1. After receiving the first packet, the receiving node checks whether this packet is using duplication and if it does, it increments an internal counter (that is initialized by default to zero). Every time that there are other duplicates belonging to the same source packet, the receiving node discard them if the counter is greater than 1. This of course imply that the UE needs to keep a different counter for each source packet. Each source packet may be identified by the sequence number, packet ID or any other ID which can be used to uniquely locate the packet.

Option 2. If multiple duplicated packets are received at the same time by the receiving node, the receiving node may keep one packets and discard the other ones of the same source packet according to the following criteria: a. The receiving UE keeps only the first received packet and discards the others. b. The receiving UE keeps only the last received packet and discards the others. c. The receiving UE keeps only the first packet generated by the source UE (according to the packet time stamps) and discards the others. d. The receiving UE keeps only the last packet generated by the source UE (according to the packet time stamps) and discards the others. e. The receiving UE keeps only the packet with sequence number (SN) equal to 1 (or 0, depending on which is the initial value) and discards the others. f. The receiving UE keeps only the packet marked as "first packet transmitted" by the source node and discards the others. g. The receiving UE keeps only the packet marked as "last packet transmitted" by the source node and discards the others.

In a fourth detailed embodiment, when the method 300 and/or 400 is performed (e.g., if duplication is applied in a dual (or multi) connectivity connection 1500), the duplication (e.g., according to the step 302 and/or 304) and/or the discarding 404 of packets may happen in different entities of the protocol stuck.

For example, the duplication 302 and/or 304 and/or the discarding 404 may be implemented at least in one of the following layers of the UE protocol stack: an SDAP layer, a PDCP layer, an RLC layer, and an adaptation layer (which may be introduced for managing duplication function).

For any one of the above options, a protocol entity may be responsible of duplicate packet in the steps 302 and 304 or the step 402 and/or only of the discarding 404 of the duplicated packets. The discarding 404 of the duplicated packets may be implemented at a destination node and/or at one or any intermediate node, e.g., depending on how the duplication and the DC (e.g., multi-connectivity) scenarios are configured.

Furthermore, every time that the protocol entity of the receiving node (e.g., 220 or 210) discards one or more duplicate packets, it may inform the protocol entity of the source node (e.g., 100) that one or more duplicate packets has been received and discarded. This indication may be generic for all the duplicated packets, or for each one of them.

For instance, the duplication of the radio bearers may be implemented at least in one of the following layers of a protocol stack of the wireless device 100 (e.g., a UE):

The layer may be the RRC layer (e.g., for signaling radio bearers or SRBs) or the SDAP layer (e.g., for data radio bearers or DRBs). In this case, there is a RRC or SDAP end-to-end radio bearer between a source (e.g., the UE) and a destination (e.g., the network) of the traffic. The UE will establish one PDCP entity for each radio bearer that is duplicated. For instance, if the UE wants to have four duplicate radio bearers, the UE will establish 4 PDCP entities one for each radio bearer that is used. Also, the PDCP entity is also responsible to receive all the duplicated packets of a certain service/traffic and make sure to discard all the packets that are duplicated. We note that in case of signaling radio bearers (SRBs) the duplication happens on the RRC layer whereas in case of data radio bearers (DRBs) the duplication happens on the SDAP layer.

Alternatively or in addition, the layer may be the PDCP layer (e.g., when Adaptation layer is present). In this case, there is a PDCP end-to-end radio bearer between a source (e.g., the UE) and a destination (e.g., the network) of the traffic. The PDCP is the layer when the duplication happens. For instance, if the UE wants to have four duplicate radio bearers, the UE will establish 4 Adaptation layer entities one for each radio bearer. Also, the PDCP entity is also responsible to receive all the duplicated packets of a certain service/traffic and make sure to discard all the packets that are duplicated.

Alternatively or in addition, the layer may PDCP layer (when Adaptation layer is not present). In this case, there is a PDCP end-to-end radio bearer between a source (e.g., the UE) and a destination (e.g., the network) of the traffic. The PDCP is the layer when the duplication happens. For instance, if the UE wants to have four duplicate radio bearers, the UE will establish 4 RLC entities one for each radio bearer. Also, the PDCP entity is also responsible to receive all the duplicated packets of a certain service/traffic and make sure to discard all the packets that are duplicated.

Alternatively or in addition, the layer may be an adaptation layer. In this case, there is an adaptation layer end-to-end radio bearer between a source (e.g., the UE) and a destination (e.g., the network) of the traffic. The adaptation layer is the layer when the duplication happens. For instance, if the UE wants to have four duplicate radio bearers, the UE will establish 4 RLC entities one for each radio bearer. Also, the adaptation layer entity is also responsible to receive all the duplicated packets of a certain service/traffic and make sure to discard all the packets that are duplicated.

Alternatively or in addition, the layer may be the RLC layer. In this case, there is an RLC end-to-end radio bearer between a source (e.g., the UE) and a destination (e.g., the network) of the traffic. The RLC layer is the layer when the duplication happens. For instance, if the UE wants to have four duplicate radio bearers, the UE will establish 4 MAC entities one for each of the radio bearers. Also, the RLC entity is also responsible to receive all the duplicated packets of a certain service/traffic and make sure to discard all the packets that are duplicated.

In a fifth detailed embodiment, upon setting up dual or multi connectivity, the UE 100 may decide to apply duplication on all the available path or to use only a single (or some of the) path at a given time.

E.g., as schematically illustrated in Fig. 17 or 18, this may mean that even if the UE 100 had established four paths, it uses only one, a portion, or all of them at a given time.

If the UE 100 decides (or is configured) to use only one or a portion of all the available paths, the decision on which path to use may be according on at least one or a combination of the following criteria:

- The UE selects the path (or paths) that have the strongest signal strength. The signal strength may be measured e.g., based on the RSRP, RSRQ, SINR, or RSSI.

- The UE selects the path (or paths) that is closer to the destination of the traffic/service. This imply that each node that the UE is able to reach inform the UE on whether is able to reach the destination and, if so, e.g., with how many hops. Alternatively, each node that the UE is able to reach informs the UE about its geographical location.

- The UE selects the path (or paths) based on a list of priorities. These priorities for each path may be configured by the gNB, by another UE, pre configured, or hard-coded in the specification.

- The UE selects the path (or paths) based on the throughput that can be achieved until the destination. This means that each node that the UE is able to reach inform the UE about the expected throughput to reach the destination of the traffic/service.

- The UE selects one, a portion, or all of the available paths based on the data volume that the UE needs to transmit.

In a sixth detailed embodiment, whenever a packet with duplication is received 402 successfully by the receiving node (e.g., 210 or 220), the receiving node may transmit signaling to other intermediate nodes which join the forwarding of the packet. The signaling may comprise at least one of the following information:

- The packet ID - The packet sequence number (SN)

- The time when the packet is received

- Whether this is the last packet transmitted (out of all the duplicates)

- Traffic ID and/or service ID and/or QoS ID

- Source node ID

- Destination node ID

- Maximum hops that the signaling can be forwarded

- Time to live of the signaling, e.g., if the time to live is expired, the signaling cannot be further forwarded or the signaling would be invalid.

Upon reception of the signaling, those intermediate nodes discard the duplicates according to the received information.

As an additional embodiment, the receiving node may send the signaling in a unicast, groupcast or broadcast fashion.

As an additional embodiment, upon reception of the signaling, any intermediate node may further forward the signaling to other neighbor nodes.

As an additional embodiment, the signaling is transmitted by the source node to the intermediate nodes/neighbor nodes when the source code has received acknowledgement from the receiving node indicating the packet has been successfully received.

As an additional embodiment, upon reception of the signaling, any intermediate node may further forward the signaling to other neighbor nodes using a signaling option which is different from the signaling option upon which the signaling has been received.

In a seventh detailed embodiment, the solutions and methods described in all the previous embodiments the UE should use is decided by the gNB and communicated to the UE via dedicated RRC signaling of via system information. As another alternative, which option the UE should use is decided by TX/RX UE or is pre-configured (hard-coded in the technical specification). In an eight embodiment, for any of the all above embodiments, the signaling alternatives described will include at least one of the below.

For example, for signaling between UE and the gNB:

- RRC signaling

- MAC CE

- LI signaling on channels such as PRACH, PUCCH, PDCCH

- Control PDU of a protocol layer such as SDAP, PDCP, RLC or an adaptation layer which is introduced for responsible of duplication function

Alternatively or in addition, for signaling between UEs:

- RRC signaling (e.g., PC5-RRC)

- PC5-S signaling

- Discovery signaling

- MAC CE

- LI signaling on channels such as PSSCH, PSCCH, or PSFCH.

- Control PDU of a protocol layer such as SDAP, PDCP, RLC or an adaptation layer which is introduced for responsible of duplication function.

In another first detailed embodiment, a UE with sidelink capabilities (i.e., standalone sidelink and/or sidelink relay capabilities) e.g., UE1, establishes a dual connectivity connection in order to reach either a destination UE or a gNB. When establishing a dual connectivity, the UE setups two active links/paths at the same time according to the following options:

Option 1. UE1 establishes a dual connectivity connection with one path of the dual connectivity connected towards the network (via Uu) directly, i.e., direct path and the other path of the dual connectivity connected towards a peer UE (via PC5). In such a case, the destination of the dual connectivity path is a gNB. Further, in such a case, the connection with the peer UE (e.g., UE2) may be standalone sidelink (if the UE2 is also the destination of the traffic) or may be sidelink relay (e.g., if the destination of the traffic is the gNB), i.e., indirect path.

Fig. 15 schematically illustrates dual connectivity (DC) with PC5 and Uu. The option 1 may be implemented according to two sub-options, e.g., depending on whether the destination gNBs of both paths 1510 and 1520 are the same or different.

Option la: UE1 connects to the same gNB (e.g., gNBl) via both one direct path and one indirect path (e.g., via UE2).

In this option, gNBl serves both Master Node (MN) and Secondary Node (SN) for UE1.

Option lb: UE1 connects to the different gNBs via both paths. UE1 connects to gNBl via one direct path.

The UE1 connects to gNB2 via one indirect path (e.g., via UE2).

For UE1, one direction is the direct path, the other direction is the indirect path. In both directions/links, one link is the master link, the other link is the secondary link.

In an example, the direct path 1520 is the master link, while the indirect path 1510 is the secondary link. Correspondingly, gNBl is the MN, while gNB2 is the SN.

In an example, the indirect path is the master link while the direct path is the secondary link. Correspondingly, gNB2 is the MN, while gNBl is the SN.

Regardless of Option la or Option lb, each radio bearer (RB) (e.g., except for SRB0 for the Uu interface) is associated with one PDCP entity.

For split bearers, each PDCP entity is associated with two UM RLC entities (for same direction), four UM RLC entities (two for each direction), or two AM RLC entities; In case of Option la, all RLC entities are configured to the same gNB, e.g., gNBl.

For RBs configured with PDCP duplication, each PDCP entity is associated with N UM RLC entities (for same direction), 2 x /V UM RLC entities ( N for each direction), or N AM RLC entities, wherein 2 <= N <= 4; In case of Option la, all RLC entities are configured to the same gNB, e.g., gNBl.

For a non-split bearer, each PDCP entity is associated with one UM RLC entity, two UM RLC entities (one for each direction), or one AM RLC entity.

UE1 may have one non-split bearer mapped onto the direct path the UE1 may also have one non-split bearer mapped onto the indirect path.

Option 2. UE1 establishes a dual connectivity connection with one path 1520 of the dual connectivity 1500 connected towards a UE3 220 (e.g., the second peer UE and/or via "PC5 link 1") and the other path (i.e., the first path) of the dual connectivity connected towards a peer UE (via PC5 link 2). In such a case, the destination of the dual connectivity path is a destination UE. Further, in such a case, the connection with the first peer UE (e.g., UE2) may be standalone sidelink (e.g., if the UE2 is also the destination of the traffic) or may be sidelink relay (e.g., if the destination of the traffic is another UE, e.g., UE3 reachable by UE2).

Fig. 16 schematically illustrates a dual connectivity using SL (e.g., with PC5) only.

This option can be implemented according to two sub-options depending on whether the destination UEs of both paths 1510 and 1520 are the same or different.

Option 2a: UE1 connects to the same UE (e.g., UE3) via both one direct path and one indirect path (e.g., via UE2).

In this option, UE3 serves both Master Node (MN) and Secondary Node (SN) for UE1.

Option 2b: UE1 connects to the different UEs via both paths. UE1 connects to UE3 via one direct path. Meanwhile, UE1 connects to UE4 via one indirect path (e.g., via UE2). A UE3 connects to UE4 via one direct connection.

For UE1, one direction is the direct path, the other direction is the indirect path. In both directions/links, one link is the master link, the other link is the secondary link. In an example, the direct path 1520 is the master link, while the indirect path 1510 is the secondary link.

In an example, the indirect path 1510 is the master link while the direct path 1520 is the secondary link.

Regardless of Option 2a or Option 2b, each RB (except for SRB0 for Uu interface) is associated with one PDCP entity.

For split bearers 800, each PDCP entity is associated with two UM RLC entities (for same direction), four UM RLC entities (two for each direction), or two AM RLC entities; In case of Option 2a, all RLC entities are configured to the same UE, e.g., UE3.

For RBs configured with PDCP duplication, each PDCP entity is associated with N UM RLC entities (for same direction), 2 x N UM RLC entities (N for each direction), or N AM RLC entities, where 2 <= N <= 4; In case of Option 2a, all RLC entities are configured to the same UE, e.g., UE3.

UE1 may have one non-split bearer mapped onto the direct path. The UE1 may also have one non-split bearer mapped onto the indirect path.

According to an Option 3, the UE 100 establishes as many multiple connections as it supports (based on its capabilities) and based on those that are available to be established. These multiple connections can be established towards one, or more peer UEs and one, or more, cell groups (e.g., MCG, SCG). Also, in this case the multi connection over PC5 may involve standalone sidelink and/or sidelink relay.

Multipath and multi-connectivity with PC5 and/or Uu when destination of the traffic is the network, e.g., as illustrated in Fig. 17 or, e.g., as illustrated in a UE according Fig. 18. In another second detailed embodiment, the UE 100 may decide to establish the paths or connection of the dual connectivity 1500 (e.g., using PC5 and Uu for the first and at least one secondary paths, respectively, or using only PC5 for the first and at least one secondary paths) according to at least one of the following triggering conditions:

A first condition is according to a certain service and/or application and/or traffic.

A second condition is a certain (e.g., predefined or configured) geographical location of the UE 100.

A third condition is when a data volume of the UE 100 (e.g., available or pending for transmission) is greater than a predefined or configured threshold. This condition may be triggered per service and/or application and/or traffic type and/or logical channel (LCH) and/or logical channel group (LCG). Alternatively or in addition, this condition may be triggered per a group of services and/or applications and/or traffic types. Alternatively or in addition, this condition may be triggered per UE 100.

A fourth condition is when the data volution of the UE 100 is greater than a configured first threshold and less than a configured second threshold. This condition may be triggered per service and/or application and/or traffic type and/or LCH and/or LCG. Alternatively, this condition may be triggered per a group of services and/or applications and/or traffic types. Alternatively, this condition may be triggered per UE.

A fifth condition is when a signal strength (e.g., a Uu signal strength or signal to noise ratio or a signal to interference and noise ratio) is less than a predefined or configured threshold. This condition may be applicable only for DC (e.g., multi connectivity) using PC5 and Uu.

A sixth condition is when the Uu signal strength is above a configured first threshold and below a configured second threshold (this is only applicable for dual/multi connectivity with PC5 and Uu).

A seventh condition is upon an indication and/or configuration from the network. An eighth condition is upon an indication and/or configuration from the network node 220 and/or a peer UE 210.

A ninth condition is upon an indication from an upper layer (e.g., of the wireless device 100).

In another third embodiment, which may be combined with the first and/or second another detailed embodiment, the UE 100 has a DC 150 (e.g., multi connectivity) connection, i.e., has established at least the first and the at least one secondary paths, means that the wireless device 100 has establish according to the steps 302 and 304 multiple radio bearer that are anchored and/or terminated at one entity of a protocol stack of the wireless device 100. This entity of the protocol stack may be the MAC, RLC, PDCP, RRC, or SDAP layer.

In another fourth detailed embodiment, which may be combined with the first, second and/or third another detailed embodiment, whether to apply DC 1500 (e.g., multi-connectivity) is decided hop-by-hop, e.g., by each receiving node functioning as an embodiment of the wireless device 100. For example, the source UE 100 decides whether to apply DC 1500 (e.g., multi-connectivity) only for those nodes (e.g., either gNB/eNB 220 or 222, or UEs 100) that are directly reachable by the source UE 100.

Once these nodes (e.g., gNB and/or eNB, or UEs) directly reachable by the source UE 100 receive source UE packets (i.e., data packets from the wireless device 100), they in turn decided to apply (or not) the DC 1500 (e.g., multi-connectivity) with the nodes (e.g., either gNB/eNB, or UEs) that are able to reach in a direct way.

In another fifth detailed embodiment, which may be combined with any one of the first to fourth another detailed embodiments, upon setting up dual or multi connectivity, the UE may decide to apply duplication on all the available path or to use only a single (or some of the) path at a given time. E.g. as schematically illustrated in Fig. 17 or 18, this means that even if the UE 100 had established three or four paths, it uses only one, a portion, or all of them at a given time.

In another sixth detailed embodiment, which may be combined with any one of the first to fifth another detailed embodiments, the selection of one, a portion, or all of the available (e.g., established) paths 1510 or 1520 (e.g., according to one or more of the criteria described in the second another detailed embodiment) is done by a semi-static or dynamic approach. In the (e.g., same) static approach when the UE 100 has the first data packets, it selects to use one, a portion, or all of the available paths and the decision does not change over time (even if the traffic is not periodic but aperiodic).

With the dynamic approach the UE 100 selects dynamically whether to use one, a portion, or all of the available (e.g., established) paths 1510 or 1520, e.g., every time that new data packets come. This can be done for example by using multiple thresholds (one for each number of path to be activated) and the UE can compare e.g., a certain criteria (e.g., data volume, signal strength, expected throughput) with each of these thresholds e.g., if a criteria is above/below first threshold two paths activated, if criteria is above or below second threshold three paths activated, and so on. Further, is the dynamic approach is used, the UE may choose to "activate" or "deactivate" a certain path by use LI signaling (e.g., downlink control information, DCI or SL control information, SCI), MAC control element (MAC CE), or a control protocol data unit (control PDU) of an adaptation layer, or an RRC signaling (over Uu or PC5).

In another seventh detailed embodiment, which may be combined with any one of the first to sixth another detailed embodiments, any one of the above embodiments is also applicable to a UE 100 with multi-connectivity (e.g., more than 2 connections, i.e., paths), wherein at least one connectivity 1510 (i.e., the first path) is based on a SL 1512.

In any embodiment, the destination nodes may comprise gNBs or UEs, which may be the same node or different nodes. The connections (i.e., the paths) may be grouped.

In another eighth detailed embodiment, which may be combined with any one of the first to seventh another detailed embodiments, the technique (i.e., devices, nodes and methods and/or as described in any of the previous embodiments) the wireless device 100 should use is decided by the network node (e.g., gNB), e.g., serving the wireless device 100) and/or is communicated to the wireless device 100, e.g., via a dedicated RRC signaling and/or via system information (SI). As another alternative, which option the wireless device 100 (e.g., among the alternative indicated in any of the embodiments) should use may be decided by the wireless device 100 and/or is pre-configured (.g., hard-coded according to a technical specification).

In another ninth detailed embodiment, which may be combined with any one of the first to seventh another detailed embodiments, for any of all above embodiments, the signaling alternatives described will include at least one of the below.

For signaling between UE and the gNB:

RRC signaling MAC CE

LI signaling on channels such as PRACH, PUCCH, PDCCH

For signaling between UEs:

RRC signaling (e.g., PC5-RRC)

PC5-S signaling Discovery signaling MAC CE

LI signaling on channels such as PSSCH, PSCCH, or PSFCH.

Herein, LI may refer to the PHY layer.

Fig. 19 shows a schematic block diagram for an embodiment of the device 100. The device 100 comprises processing circuitry, e.g., one or more processors 1904 for performing the method 300 and memory 1906 coupled to the processors 1904.

For example, the memory 1906 may be encoded with instructions that implement at least one of the modules 102 and 104.

The one or more processors 1904 may be a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, microcode and/or encoded logic operable to provide, either alone or in conjunction with other components of the device 100, such as the memory 1906, wireless device and/or transmitter functionality. For example, the one or more processors 1904 may execute instructions stored in the memory 1906. Such functionality may include providing various features and steps discussed herein, including any of the benefits disclosed herein. The expression "the device being operative to perform an action" may denote the device 100 being configured to perform the action.

As schematically illustrated in Fig. 19, the device 100 may be embodied by a wireless device 1900, e.g., functioning as a UE. The wireless device 1900 comprises a radio interface 1902 coupled to the device 100 for radio communication with one or more UEs and/or network nodes.

Fig. 20 shows a schematic block diagram for an embodiment of the device 210 or 220. The device 210 or 220 comprises processing circuitry, e.g., one or more processors 2004 for performing the method 400 and memory 2006 coupled to the processors 2004. For example, the memory 2006 may be encoded with instructions that implement at least one of the modules 202 and 204.

The one or more processors 2004 may be a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, microcode and/or encoded logic operable to provide, either alone or in conjunction with other components of the device 200, such as the memory 2006, wireless device or network node and/or receiver functionality. For example, the one or more processors 2004 may execute instructions stored in the memory 2006. Such functionality may include providing various features and steps discussed herein, including any of the benefits disclosed herein. The expression "the device being operative to perform an action" may denote the device 200 being configured to perform the action.

As schematically illustrated in Fig. 20, the device 210 or 220 may be embodied by a network node 2000, e.g., functioning as a base station. The network node 2000 comprises a radio interface 2002 coupled to the device 210 or 220 for radio communication with one or more UEs.

With reference to Fig. 21, in accordance with an embodiment, a communication system 2100 includes a telecommunication network 2110, such as a 3GPP-type cellular network, which comprises an access network 2111, such as a radio access network, and a core network 2114. The access network 2111 comprises a plurality of base stations 2112a, 2112b, 2112c, such as NBs, eNBs, gNBs or other types of wireless access points, each defining a corresponding coverage area 2113a, 2113b, 2113c. Each base station 2112a, 2112b, 2112c is connectable to the core network 2114 over a wired or wireless connection 2115. A first user equipment (UE) 2191 located in coverage area 2113c is configured to wirelessly connect to, or be paged by, the corresponding base station 2112c. A second UE 2192 in coverage area 2113a is wirelessly connectable to the corresponding base station 2112a. While a plurality of UEs 2191, 2192 are illustrated in this example, the disclosed embodiments are equally applicable to a situation where a sole UE is in the coverage area or where a sole UE is connecting to the corresponding base station 2112.

Any of the base stations 2112 and the UEs 2191, 2192 may embody the device 100.

The telecommunication network 2110 is itself connected to a host computer 2130, which may be embodied in the hardware and/or software of a standalone server, a cloud-implemented server, a distributed server or as processing resources in a server farm. The host computer 2130 may be under the ownership or control of a service provider, or may be operated by the service provider or on behalf of the service provider. The connections 2121, 2122 between the telecommunication network 2110 and the host computer 2130 may extend directly from the core network 2114 to the host computer 2130 or may go via an optional intermediate network 2120. The intermediate network 2120 may be one of, or a combination of more than one of, a public, private or hosted network; the intermediate network 2120, if any, may be a backbone network or the Internet; in particular, the intermediate network 2120 may comprise two or more sub-networks (not shown).

The communication system 2100 of Fig. 21 as a whole enables connectivity between one of the connected UEs 2191, 2192 and the host computer 2130. The connectivity may be described as an over-the-top (OTT) connection 2150. The host computer 2130 and the connected UEs 2191, 2192 are configured to communicate data and/or signaling via the OTT connection 2150, using the access network 2111, the core network 2114, any intermediate network 2120 and possible further infrastructure (not shown) as intermediaries. The OTT connection 2150 may be transparent in the sense that the participating communication devices through which the OTT connection 2150 passes are unaware of routing of uplink and downlink communications. For example, a base station 2112 need not be informed about the past routing of an incoming downlink communication with data originating from a host computer 2130 to be forwarded (e.g., handed over) to a connected UE 2191. Similarly, the base station 2112 need not be aware of the future routing of an outgoing uplink communication originating from the UE 2191 towards the host computer 2130.

By virtue of the method 300 being performed by any one of the UEs 2191 or 2192 and/or the method 400 being performed by any one of the network node (e.g., base stations) 2112, the performance or range of the OTT connection 2150 can be improved, e.g., in terms of increased throughput and/or reduced latency. More specifically, the host computer 2130 may indicate to wireless device 100, network node 220, the first peer wireless device 210 and/or the RAN (e.g., on an application layer) any one of the triggering conditions (e.g., of the second detailed embodiment), e.g., a QoS of the traffic.

Example implementations, in accordance with an embodiment of the UE, base station and host computer discussed in the preceding paragraphs, will now be described with reference to Fig. 22. In a communication system 2200, a host computer 2210 comprises hardware 2215 including a communication interface 2216 configured to set up and maintain a wired or wireless connection with an interface of a different communication device of the communication system 2200. The host computer 2210 further comprises processing circuitry 2218, which may have storage and/or processing capabilities. In particular, the processing circuitry 2218 may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The host computer 2210 further comprises software 2211, which is stored in or accessible by the host computer 2210 and executable by the processing circuitry 2218. The software 2211 includes a host application 2212. The host application 2212 may be operable to provide a service to a remote user, such as a UE 2230 connecting via an OTT connection 2250 terminating at the UE 2230 and the host computer 2210. In providing the service to the remote user, the host application 2212 may provide user data, which is transmitted using the OTT connection 2250. The user data may depend on the location of the UE 2230. The user data may comprise auxiliary information or precision advertisements (also: ads) delivered to the UE 2230. The location may be reported by the UE 2230 to the host computer, e.g., using the OTT connection 2250, and/or by the base station 2220, e.g., using a connection 2260.

The communication system 2200 further includes a base station 2220 provided in a telecommunication system and comprising hardware 2225 enabling it to communicate with the host computer 2210 and with the UE 2230. The hardware 2225 may include a communication interface 2226 for setting up and maintaining a wired or wireless connection with an interface of a different communication device of the communication system 2200, as well as a radio interface 2227 for setting up and maintaining at least a wireless connection 2270 with a UE 2230 located in a coverage area (not shown in Fig. 22) served by the base station 2220. The communication interface 2226 may be configured to facilitate a connection 2260 to the host computer 2210. The connection 2260 may be direct, or it may pass through a core network (not shown in Fig. 22) of the telecommunication system and/or through one or more intermediate networks outside the telecommunication system. In the embodiment shown, the hardware 2225 of the base station 2220 further includes processing circuitry 2228, which may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The base station 2220 further has software 2221 stored internally or accessible via an external connection.

The communication system 2200 further includes the UE 2230 already referred to. Its hardware 2235 may include a radio interface 2237 configured to set up and maintain a wireless connection 2270 with a base station serving a coverage area in which the UE 2230 is currently located. The hardware 2235 of the UE 2230 further includes processing circuitry 2238, which may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The UE 2230 further comprises software 2231, which is stored in or accessible by the UE 2230 and executable by the processing circuitry 2238. The software 2231 includes a client application 2232. The client application 2232 may be operable to provide a service to a human or non-human user via the UE 2230, with the support of the host computer 2210. In the host computer 2210, an executing host application 2212 may communicate with the executing client application 2232 via the OTT connection 2250 terminating at the UE 2230 and the host computer 2210. In providing the service to the user, the client application 2232 may receive request data from the host application 2212 and provide user data in response to the request data. The OTT connection 2250 may transfer both the request data and the user data. The client application 2232 may interact with the user to generate the user data that it provides.

It is noted that the host computer 2210, base station 2220 and UE 2230 illustrated in Fig. 22 may be identical to the host computer 2130, one of the base stations 2112a, 2112b, 2112c and one of the UEs 2191, 2192 of Fig. 21, respectively. This is to say, the inner workings of these entities may be as shown in Fig. 22, and, independently, the surrounding network topology may be that of Fig. 21.

In Fig. 22, the OTT connection 2250 has been drawn abstractly to illustrate the communication between the host computer 2210 and the UE 2230 via the base station 2220, without explicit reference to any intermediary devices and the precise routing of messages via these devices. Network infrastructure may determine the routing, which it may be configured to hide from the UE 2230 or from the service provider operating the host computer 2210, or both. While the OTT connection 2250 is active, the network infrastructure may further take decisions by which it dynamically changes the routing (e.g., on the basis of load balancing consideration or reconfiguration of the network).

The wireless connection 2270 between the UE 2230 and the base station 2220 is in accordance with the teachings of the embodiments described throughout this disclosure. One or more of the various embodiments improve the performance of OTT services provided to the UE 2230 using the OTT connection 2250, in which the wireless connection 2270 forms the last segment. More precisely, the teachings of these embodiments may reduce the latency and improve the data rate and thereby provide benefits such as better responsiveness and improved QoS.

A measurement procedure may be provided for the purpose of monitoring data rate, latency, QoS and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring the OTT connection 2250 between the host computer 2210 and UE 2230, in response to variations in the measurement results. The measurement procedure and/or the network functionality for reconfiguring the OTT connection 2250 may be implemented in the software 2211 of the host computer 2210 or in the software 2231 of the UE 2230, or both. In embodiments, sensors (not shown) may be deployed in or in association with communication devices through which the OTT connection 2250 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or supplying values of other physical quantities from which software 2211, 2231 may compute or estimate the monitored quantities. The reconfiguring of the OTT connection 2250 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not affect the base station 2220, and it may be unknown or imperceptible to the base station 2220. Such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signaling facilitating the host computer's 2210 measurements of throughput, propagation times, latency and the like. The measurements may be implemented in that the software 2211, 2231 causes messages to be transmitted, in particular empty or "dummy" messages, using the OTT connection 2250 while it monitors propagation times, errors etc.

Fig. 23 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a UE which may be those described with reference to Figs. 21 and 22. For simplicity of the present disclosure, only drawing references to Fig. 23 will be included in this paragraph. In a first step 2310 of the method, the host computer provides user data. In an optional substep 2311 of the first step 2310, the host computer provides the user data by executing a host application. In a second step 2320, the host computer initiates a transmission carrying the user data to the UE. In an optional third step 2330, the base station transmits to the UE the user data which was carried in the transmission that the host computer initiated, in accordance with the teachings of the embodiments described throughout this disclosure. In an optional fourth step 2340, the UE executes a client application associated with the host application executed by the host computer.

Fig. 24 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a UE which may be those described with reference to Figs. 21 and 22. For simplicity of the present disclosure, only drawing references to Fig. 24 will be included in this paragraph. In a first step 2410 of the method, the host computer provides user data. In an optional substep (not shown) the host computer provides the user data by executing a host application. In a second step 2420, the host computer initiates a transmission carrying the user data to the UE. The transmission may pass via the base station, in accordance with the teachings of the embodiments described throughout this disclosure. In an optional third step 2430, the UE receives the user data carried in the transmission.

As has become apparent from above description, at least some embodiments of the technique allow a node (e.g., the first peer wireless device 210, and/or the at least one station 220) to discard multiple duplicates received, in a scenario where DC (e.g., multi-connectivity) and packet duplication is used (e.g., by the wireless device 100). This can increase the UE power saving, e.g., since not all the duplicated packets need to be processed. Alternatively or in addition, this can improve the latency, e.g., since only one packet is kept out of all the ones that are duplicated. Alternatively or in addition, this can reduce a signaling overhead and/or improve resource efficiency.

Same or further embodiments work for in-coverage, out-of-coverage and partial coverage scenarios enhancing the reliability of the transmissions in all of them, and additionally, increasing the network coverage (potentially) for the latter scenario.

Many advantages of the present invention will be fully understood from the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of the units and devices without departing from the scope of the invention and/or without sacrificing all of its advantages. Since the invention can be varied in many ways, it will be recognized that the invention should be limited only by the scope of the following claims.

Claims

1. A method (300) of transmitting duplicated packets on a dual connectivity,

DC (1500), of a wireless device (100), the method (300) comprising or initiating the steps of: transmitting (302) at least one packet of the duplicated packets over a first path (1510) of the DC (1500), wherein the first path (1510) of the DC (1500) is wirelessly connected from the wireless device (100; 1900; 2191; 2192; 2230) towards a first peer wireless device (210) using a first sidelink, SL (1512), between the wireless device (100; 1900; 2191; 2192; 2230) and the first peer wireless device (210); and transmitting (304) at least one packet of the duplicated packets over at least one secondary path (1520) of the DC (1500), wherein each of the at least one packet over the at least one secondary path (1520) is a duplication of each of the at least one packet over the first path (1510), wherein the at least one secondary path (1520) of the DC (1500) is wirelessly connected from the wireless device (100; 1900; 2191; 2192; 2230) towards at least one station (220) other than the first peer wireless device (210).

2. The method (300) of claim 1, wherein at least one or each of the duplicated packets comprises or is indicative of at least one of: an indication that the respective packet is a duplicated packet or that the duplication is activated; an indication of whether or not the respective packet is a duplicated packet or whether or not the duplication is activated; a total number of the duplicated packets generated or transmitted for the respective packet; a packet identifier, ID, of the respective packet; a packet sequence number, SN, of the respective packet; whether the respective packet is the first packet transmitted or to be transmitted among the duplicated packets; whether the respective packet is the last packet transmitted or to be transmitted among the duplicated packets; a packet time stamp indicative of a time when the respective packet has been transmitted (302; 304) by the wireless device (100); a packet time stamp indicative of a time when the respective packet has been generated, optionally by the wireless device (100); a traffic ID of a type of traffic to which the respective packet or the duplicated packets belong; a service ID of a service using the packets; a QoS ID of a quality of service, QoS, associated with the packets; a source node ID of a source node of the respective packet; a source node ID of the wireless device (100); and a destination node ID of a destination node of the respective packet.

3. The method (300) of claim 1 or 2, wherein the method (300) is performed by the wireless device (100).

4. The method (300) of any one of claims 1 to 3, wherein both the first path (1510) and the at least one secondary path (1520) carry a radio bearer, RB, that is anchored at an entity of an anchoring layer, optionally an anchoring layer of the master node or the secondary node.

5. The method (300) of claim 4, wherein the anchoring layer comprises at least one of a medium access control, MAC, layer; a radio link control, RLC, layer; a packet data convergence protocol, PDCP, layer; a radio resource control, RRC, layer; and a service data adaptation protocol, SDAP, layer.

6. The method (300) of claim 4 or 5, wherein the bearer is at least one of split and duplicated at a split layer below the anchoring layer.

7. The method (300) of claim 6, wherein the split layer comprises at least one of a physical, PHY, layer; a medium access control, MAC, layer; a radio link control, RLC, layer; a packet data convergence protocol, PDCP, layer; and a radio resource control, RRC, layer.

8. The method (300) of any one of claims 4 to 7, wherein the bearer is a split bearer (800) anchored at a PDCP entity associated with one or two Unacknowledged Mode, UM, RLC entities for the first path (1510) and associated with one or two UM RLC entities for the at least one secondary path (1520). 9. The method (300) of any one of claims 4 to 7 , wherein the bearer is a split bearer (800) anchored at a PDCP entity associated with one Acknowledged Mode, AM, RLC entities for the first path (1510) and associated with one AM RLC entities for the at least one secondary path (1520).

10. The method (300) of any one of claims 4 to 7, wherein the bearer is configured for the duplication at a PDCP entity associated with N or IN UM RLC entities for the first path (1510) and associated with N or IN UM RLC entities for the at least one secondary path (1520).

11. The method (300) of any one of claims 4 to 7, wherein the bearer is configured for the duplication at a PDCP entity associated with N AM RLC entities for the first path (1510) and associated with N AM RLC entities for the at least one secondary path (1520).

12. The method (300) of any one of claims 1 to 11, wherein the first path (1510) carries a first non-split RB, and/or the at least one secondary path (1520) carries a second non-split RB.

13. The method (300) of any one of claims 1 to 12, wherein a first non-split RB mapped to the first path (1510) is associated with a first PDCP entity and one or two first UM RLC entities or one first AM RLC entity, and/or wherein a second non-split RB mapped to the at least one secondary path (1510) is associated with a second PDCP entity and one or two second UM RLC entities or one second AM RLC entity.

14. The method (300) of any one of claims 1 to 13, wherein the transmitting (302) of the at least one packet over the first path (1510) is prior to or starts earlier than the transmitting (304) of the at least one packet over the at least one secondary path (1520), or wherein the transmitting (304) of the at least one packet over the at least one secondary path (1520) is prior to or starts earlier than the transmitting (302) of the at least one packet over the first path (1520), or wherein the duplicated packets are sequentially transmitted (302, 304) on the first and secondary paths (1510, 1520).

15. The method (300) of any one of claims 1 to 14, wherein the at least one packet over the at least one secondary path (1520) is transmitted (304) responsive to an absent or outstanding acknowledgment of the at least one packet transmitted (302) over the first path (1510), or wherein the at least one packet over the first path (1510) is transmitted (302) responsive to an absent or outstanding acknowledgment of the at least one packet transmitted (304) over the at least one secondary path (1520).

16. The method (300) of any one of claims 1 to 15, wherein the at least one secondary path (1520) comprises a first secondary path (1520) and a second secondary path (1520), and wherein the transmitting (304) of the at least one packet over the at least one secondary path (1520) of the DC (1500) comprises: transmitting at least one packet of the duplicated packets over the first secondary path (1520), wherein each of the at least one packet over the first secondary path (1520) is a duplication of each of the at least one packet over the first path (1510); and responsive to an absent or outstanding acknowledgment of the at least one packet transmitted over the first secondary path (1520), transmitting at least one packet of the duplicated packets over the second secondary path (1520), wherein each of the at least one packet over the second secondary path (1520) is a duplication of each of the at least one packet over the first path (1510).

17. The method (300) of any one of claims 1 to 16, wherein the wireless device (100) stops transmitting (302, 304) on all the first and secondary paths (1510,

1520) and/or releases all the first and secondary paths (1510, 1520), if no acknowledgement of the transmitted (302, 304) at least one packet is received via any of the first and secondary paths (1510, 1520).

18. The method (300) of any one of claims 1 to 17, wherein the wireless device (100) stops transmitting (304) on a subset of the first and secondary paths (1510, 1520) and/or releases a subset of the first and secondary paths (1510, 1520), wherein the subset comprises those paths (1510, 1520) via which no acknowledgement of the transmitted (302, 304) at least one packet is received.

19. The method (300) of any one of claims 1 to 18, wherein the at least one packet over the first path (1510) is transmitted (302) simultaneously with the transmitting (304) of the at least one packet over the at least one secondary path (1520). 20. The method (300) of any one of claims 1 to 19, further comprising or initiating the steps of: starting a timer upon the transmitting (302, 304) of the at least one packet of the duplicated packets over the first path and/or the at least one secondary path.

21. The method (300) of claims 19 and 20, wherein the wireless device (100) stops transmitting (302, 304) on all the first and secondary paths (1510, 1520) and/or releases all the first and secondary paths (1510, 1520), if no acknowledgement of the transmitted (302, 304) packet is received via any of the first and secondary paths (1510, 1520) upon expiry of the timer.

22. The method (300) of claims 19 and 20, wherein the wireless device (100) stops transmitting (302, 304) on a subset of the first and secondary paths (1510, 1520) and/or releases a subset of the first and secondary paths (1510, 1520), wherein the subset comprises those paths (1510, 1520) via which no acknowledgement of the transmitted (302, 304) at least one packet is received upon expiry of the timer.

23. The method (300) of claim 22 or claims 19 and 20, wherein the wireless device (100) keeps transmitting (302, 304) on a subset of the first and secondary paths (1510, 1520) after expiry of the timer, wherein the subset comprises those paths (1510, 1520) via which an acknowledgement of the transmitted (302, 304) at least one packet has been received upon expiry of the timer.

24. The method (300) of any one of claims 19 to 23, wherein the transmission (302, 304) of the duplicated packets comprises transmitting the duplicated packets on all the first and secondary paths (1510, 1520) at a periodic interval and/or triggered by a duplication condition, optionally as long as the timer is not expired.

25. The method (300) of any one of claims 1 to 24, wherein the wireless device (100) performs the transmission (302, 304) of the duplicated packets if or as long as a duplication conditions is fulfilled.

26. The method (300) of claim 24 or 25, further comprising or initiating, responsive to a first acknowledgement of the transmitted (302, 304) at least one packet received via one of the first and secondary paths (1510, 1520), at least one of the steps of: stopping the transmission (302, 304) of the duplicated packets over all of the first and secondary paths (1510, 1520); and releasing each of the first and secondary paths (1510, 1520) except for the path (1510; 1520) via which the first acknowledgement of the transmitted (302, 304) at least one packet has been received.

27. The method (300) of any one of claims 1 to 26, wherein the step (302) of transmitting the at least one packet of the duplicated packets over the first path (1510) comprises transmitting a sequence of the duplicated packets over the first path (1510), and/or wherein the step (302) of transmitting the at least one packet of the duplicated packets over the at least one secondary path (1520) comprises transmitting a sequence of the duplicated packets over the at least one secondary path (1520).

28. The method (300) of any one of claims 1 to 27, wherein the at least one station (220) is or comprises one or more network nodes or one or more cell groups, and/or wherein a wireless access network (500) comprises the at least one station (220).

29. The method (300) of claim 28, wherein the at least one station (220) is or comprises at least one of a master node of the DC (1500), a master cell group, MCG, of the DC (1500), a secondary node of the DC (1500), and a secondary cell group, SCG, of the DC (1500).

30. The method (300) of any one of claims 1 to 29, wherein the at least one secondary path (1520) of the DC (1500) is wirelessly connected towards the at least one station (220) using at least one of an uplink, a downlink, and a Uu interface (1522) between the wireless device (100; 1900; 2191; 2192; 2230) and the at least one station (220).

31. The method (300) of any one of claims 1 to 30, wherein the first peer wireless device (210) is a relay wireless device relaying the first path (1510) of the DC (1500) from the wireless device (100; 1900; 2191; 2192; 2230) to the at least one station (220) and/or to the wireless access network (500) comprising the at least one station (220).

32. The method (300) of claim 31, wherein the at least one secondary path (1520) is wirelessly connected towards one station (220), and the first path (1510) of the DC (1500) is relayed to the one station (220), optionally wherein the one station (220) is or comprises both a master node and a secondary node of the DC (1500) of the wireless device (100; 1900; 2191; 2192; 2230).

33. The method (300) of any one of claims 1 to 32, wherein the at least one station (220) is at least one network node of a wireless access network (500), and wherein the first peer wireless device (210) is a relay wireless device relaying the first path (1510) of the DC (1500) from the wireless device (100; 1900; 2191; 2192; 2230) to at least one further network node (222) of the wireless access network (500) comprising the at least one network node (220).

34. The method (300) of claim 33, wherein the at least one further network node (222) is or comprises a master node of the DC (1500) of the wireless device (100; 1900; 2191; 2192; 2230), and/or wherein the at least one a station (220) is or comprises at least one secondary node of the DC (1500) of the wireless device (100; 1900; 2191; 2192; 2230).

35. The method (300) of claim 33, wherein the at least one further network node (222) is or comprises at least one secondary node of the DC (1500) of the wireless device (100; 1900; 2191; 2192; 2230), and/or wherein the at least one a station (220) is or comprises a master node of the DC (1500) of the wireless device (100; 1900; 2191; 2192; 2230).

36. The method (300) of any one of claims 1 to 35, wherein the at least one station (220) is or comprises a second peer wireless device.

37. The method (300) of claim 36, wherein the at least one secondary path (1520) of the DC is wirelessly connected towards the second peer wireless device (220) using at least one of a second SL (1622) and a PC5 interface (1622) between the wireless device (100; 1900; 2191; 2192; 2230) and the second peer wireless device (220). 38. The method (300) of claim 36 or 37, wherein the first peer wireless device (210) is a relay wireless device relaying the first path (1510) of the DC (1500) from the wireless device (100; 1900; 2191; 2192; 2230) to the second peer wireless device (220), optionally wherein the second peer wireless device (220) is or comprises both a master node and a secondary node of the DC (1500) of the wireless device (100; 1900; 2191; 2192; 2230).

39. The method (300) of claim 37, wherein the first peer wireless device (210) is a relay wireless device relaying the first path (1510) of the DC (1500) from the wireless device (100; 1900; 2191; 2192; 2230) to at least one further wireless device other than the second peer wireless device (220).

40. The method (300) of claim 39, wherein the at least one further wireless device is or comprises a master node of the DC (1500) of the wireless device (100; 1900; 2191; 2192; 2230), and/or wherein the second peer wireless device (220) is or comprises at least one secondary node of the DC (1500) of the wireless device (100; 1900; 2191; 2192; 2230).

41. The method (300) of claim 39, wherein the at least one further wireless device is or comprises a secondary node of the DC (1500) of the wireless device (100; 1900; 2191; 2192; 2230), and/or wherein the second peer wireless device (220) is or comprises at least one master node of the DC (1500) of the wireless device (100; 1900; 2191; 2192; 2230).

42. The method (300) of any one of claims 1 to 41, wherein a wireless ad hoc network (1600) comprises at least one of the wireless device (100; 1900; 2191; 2192; 2230), the first peer wireless device (210) and the at least one station (220).

43. The method (300) of any one of claims 1 to 42, wherein the wireless connection of the first path (1510) from the wireless device (100; 1900; 2191;

2192; 2230) towards the first peer wireless device (210) using the first SL (1512) between the wireless device (100; 1900; 2191; 2192; 2230) and the first peer wireless device (210) is a master link of the DC (1500) of the wireless device (100; 1900; 2191; 2192; 2230), and/or wherein the wireless connection of the at least one secondary path (1520) from the wireless device (100; 1900; 2191; 2192; 2230) towards the at least one station (220) is a secondary link of the DC (1500) of the wireless device (100; 1900; 2191; 2192; 2230).

44. The method (300) of any one of claims 1 to 43, wherein the wireless connection of the first path (1510) from the wireless device (100; 1900; 2191;

2192; 2230) towards the first peer wireless device (210) using the first SL (1512) between the wireless device (100; 1900; 2191; 2192; 2230) and the first peer wireless device (210) is a secondary link of the DC (1500) of the wireless device (100; 1900; 2191; 2192; 2230), and/or wherein the wireless connection of the at least one secondary path (1520) from the wireless device (100; 1900; 2191; 2192; 2230) towards the at least one station (220) is a master link of the DC (1500) of the wireless device (100; 1900; 2191; 2192; 2230).

45. The method (300) of any one of claims 1 to 44, wherein the at least one packet is transmitted (302) from the wireless device (100; 1900; 2191; 2192; 2230) to the first peer wireless device (210) in the first path (1510) of the DC (1500).

46. The method (300) of any one of claims 1 to 45, wherein the at least one packet is transmitted (304) from the wireless device (100; 1900; 2191; 2192; 2230) to the at least one station (220) in the at least one secondary path (1520) of the DC (1500).

47. The method (300) of any one of claims 1 to 46, wherein the DC (1500) is a multi-connectivity comprising more than two paths (1510, 1520),

48. The method (300) of any one of claims 1 to 47, wherein at least one or each of the steps (302, 304) of transmitting is performed according to at least one of the following duplication conditions: according to a duplication condition that depends on, or is controlled, by at least one of a service using the DC (1500), an application using the DC (1500), and a traffic transmitted using the DC (1500); in predefined or configured geographical location; when a level of a QoS of data pending for the transmission (302, 304) at the wireless device (100; 1900; 2191; 2192; 2230) is greater than a predefined or configured threshold value; when a signal strength of one or each of the at least one network node (220) at the Uu interface (1522) is less than a predefined or configured threshold value; upon an indication and/or configuration from the at least one network node (220) or the wireless access network (500); upon an indication and/or configuration from the peer wireless device

(210); upon an indication from an upper layer of a communication protocol stack at the wireless device (100; 1900; 2191; 2192; 2230); and upon an indication received from a host computer of an application and/or service used at the wireless device (100; 1900; 2191; 2192; 2230).

49. The method (300) of any one of claims 1 to 48, wherein the wireless device (100; 1900; 2191; 2192; 2230) selects whether to activate the duplication on one, a portion, or all of the paths (1510; 1520), optionally every time that a packet for transmission (302, 304) becomes available at the wireless device (100; 1900; 2191; 2192; 2230).

50. A method (400) of receiving duplicated packets on a dual connectivity, DC (1500), of a wireless device (100), wherein the method (400) comprises or initiates at least one of the steps of: receiving (402-1) at least one packet of the duplicated packets over a first path (1510) of the DC (1500), wherein the first path (1510) of the DC (1500) is wirelessly connected from the wireless device (100; 1900; 2191; 2192; 2230) towards a first peer wireless device (210) using a first sidelink, SL (1512), between the wireless device (100; 1900; 2191; 2192; 2230) and the first peer wireless device (210); and receiving (402-2) at least one packet of the duplicated packets over at least one secondary path (1520) of the DC (1500), wherein the at least one secondary path (1520) of the DC (1500) is wirelessly connected from the wireless device (100; 1900; 2191; 2192; 2230) towards at least one station (220) other than the first peer wireless device (210), and wherein the method (400) further comprises or initiates the step of discarding (404) at least one of the received (402-1; 402-2) duplicated packets. 51. The method (400) of claim 50, wherein each of the at least one packet received (402-2) over the at least one secondary path (1520) is a duplication of each of the at least one packet received (402-1) over the first path (1510).

52. The method (400) of claim 50 or 51, wherein all except one of the received (402-1; 402-2) at least one packet of the duplicated packets are discarded (404).

53. The method (400) of any one of claims 50 to 52, further comprising or initiating the step of: incrementing a counter for each of the received at least one packet if the respective packet is indicative that the respective packet is a duplicated packet or that the duplication is activated.

54. The method (400) of claim 53, wherein such a counter is maintained for each of service or service ID, and/or for each traffic or traffic ID, and/or for each QoS or QoS ID, and/or for each packet ID, and/or for each source node or source node ID, and/or for each destination node or destination node ID.

55. The method (400) of any one of claims 50 to 54, wherein the step (404) of discarding comprises checking if two or more packets have been received (402-1; 402-1) which are indicative of or which belong to the same service or service ID, and/or the same traffic or traffic ID, and/or the same QoS or QoS ID, and/or the same packet ID, and/or the same source node or source node ID, and/or the same destination node or destination node ID.

56. The method (400) of claim 55, wherein the step (404) of discarding comprises discarding all except one of the two or more packets per service or service ID, and/or per traffic or traffic ID, and/or per QoS or QoS ID, and/or per packet ID, and/or per source node or source node ID, and/or per destination node or destination node ID. 57. The method (400) of any one of claims 50 to 56, wherein the step (404) of discarding comprises: upon receiving (402-1; 402-1) of each of the at least one packet, discarding the respective packet if another packet has been previously received which is indicative of or which belongs to the same service or service ID, and/or the same traffic or traffic ID, and/or the same QoS or QoS ID, and/or the same packet ID, and/or the same source node or source node ID, and/or the same destination node or destination node ID.

58. The method (400) of any one of claims 50 to 57, wherein upon receiving (402-1; 402-2) multiple packets at the same time, the step (404) of discarding comprises at least one of: keeping only the first received packet and discarding the other received packets among the multiple packets; keeping only the last received packet and discarding the other received packets among the multiple packets; keeping only the packet transmitted or generated first among the multiple packets, optionally according to a packet time stamp of the respective one of the multiple packets, and discarding the other received packets among the multiple packets; keeping only the packet transmitted or generated last among the multiple packets, optionally according to a packet time stamp of the respective one of the multiple packets, and discarding the other received packets among the multiple packets; keeping only the packet indicative of a packet SN equal to 0 or 1, and discarding the other received packets among the multiple packets; keeping only the packet indicative of being the first packet transmitted by the source node among the multiple packets, and discarding the other received packets among the multiple packets; and keeping only the packet indicative of being the last packet transmitted by the source node among the multiple packets, and discarding the other received packets among the multiple packets.

59. The method (400) of any one of claims 50 to 58, wherein the method (400) is performed by the at least one station (220) or the first peer wireless device (210). 60. The method (400) of any one of claims 50 to 59, further comprising the features of steps of any one of claims 2 to 49, or any feature or step corresponding thereto.

61. A computer program product comprising program code portions for performing the steps of any one of the claims 1 to 49 or 50 to 60 when the computer program product is executed on one or more computing devices (1904; 1204), optionally stored on a computer-readable recording medium (1106; 1206).

62. A wireless device (100; 1900; 2191; 2192; 2230) transmitting duplicated packets on a dual connectivity, DC (1500), of the wireless device (100; 1900; 2191; 2192; 2230), the wireless device (100; 1900; 2191; 2192; 2230) comprising memory operable to store instructions and processing circuitry operable to execute the instructions, such that the wireless device (100; 1900; 2191; 2192; 2230) is operable to: transmit at least one packet of the duplicated packets over a first path (1510) of the DC (1500), wherein the first path (1510) of the DC (1500) is wirelessly connected from the wireless device (100; 1900; 2191; 2192; 2230) towards a first peer wireless device (210) using a first sidelink, SL (1512), between the wireless device (100; 1900; 2191; 2192; 2230) and the first peer wireless device (210); and transmit at least one packet of the duplicated packets over at least one secondary path (1520) of the DC (1500), wherein each of the at least one packet over the at least one secondary path (1520) is a duplication of each of the at least one packet over the first path (1510), wherein the secondary path (1520) of the DC (1500) is wirelessly connected from the wireless device (100; 1900; 2191; 2192; 2230) towards at least one station (220) other than the first peer wireless device (210).

63. The wireless device (100; 1900; 2191; 2192; 2230) of claim 62, further operable to perform the steps of any one of claims 2 to 49.

64. A node (220) for receiving duplicated packets on a dual connectivity, DC (1500), of a wireless device (100; 1900; 2191; 2192; 2230), the node (220) comprising memory operable to store instructions and processing circuitry operable to execute the instructions, such that the node (220) is operable to at least one of: receive at least one packet of the duplicated packets over a first path (1510) of the DC (1500), wherein the first path (1510) of the DC (1500) is wirelessly connected from the wireless device (100; 1900; 2191; 2192; 2230) towards a first peer wireless device (210) using a first sidelink, SL (1512), between the wireless device (100; 1900; 2191; 2192; 2230) and the first peer wireless device (210); and receive at least one packet of the duplicated packets over at least one secondary path (1520) of the DC (1500), wherein the secondary path (1520) of the DC (1500) is wirelessly connected from the wireless device (100; 1900; 2191; 2192; 2230) towards at least one station (220) other than the first peer wireless device (210), and such that the node (220) is further operable to discard at least one of the received (402-1; 402-2) duplicated packets.

65. The node (220) of claim 64, further comprising any feature or being operable to perform any step of any one of the claims 50 to 60.

66. A communication system (2100; 2200) including a host computer (2130; 2210) comprising: processing circuitry (2218) configured to provide user data; and a communication interface (2216) configured to forward user data to a cellular or ad hoc radio network (500; 1310) for transmission to a user equipment, UE, (100; 1900; 2191; 2192; 2230) wherein the UE (100; 1900; 2191; 2192; 2230) comprises a radio interface (1902; 2237) and processing circuitry (1904; 2238), the processing circuitry (1904; 2238) of the UE (100; 1900; 2191; 2192; 2230) being configured to execute the steps of any one of claims 1 to 49.

67. The communication system (2100; 2200) of claim 66, further including the UE (100; 1900; 2191; 2192; 2230).

68. The communication system (2100; 2200) of claim 66 or 67, wherein the radio network (1310) further comprises a base station (220; 2000; 2112; 2220), or a radio device (100; 210; 1900; 2191; 2192; 2230) functioning as a gateway, which is configured to communicate with the UE (100; 1900; 2191; 2192; 2230). 69. The communication system (2100; 2200) of claim 68, wherein the base station (220; 2000; 2112; 2220), or the radio device (100; 210; 1900; 2191; 2192; 2230) functioning as a gateway, comprises processing circuitry (1904; 2228), which is configured to execute the steps of any one of claims 50 to 60.

70. The communication system (2100; 2200) of any one of claims 66 to 69, wherein: the processing circuitry (2218) of the host computer (2130; 2210) is configured to execute a host application (2212), thereby providing the user data; and the processing circuitry (1904; 2238) of the UE (100; 1900; 2191; 2192; 2230) is configured to execute a client application (2232) associated with the host application (2212).