WO2021008687A1

WO2021008687A1 - Device and method for processing ethernet-based traffic

Info

Publication number: WO2021008687A1
Application number: PCT/EP2019/069084
Authority: WO
Inventors: Ali Ramadan ALI; Sandip GANGAKHEDKAR; Karthikeyan Ganesan; Hanwen Cao; Josef Eichinger; Mohamed GHARBA
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2019-07-16
Filing date: 2019-07-16
Publication date: 2021-01-21

Abstract

A device for a wireless communication network is disclosed. The wireless communication network comprises a core network device, a base station, one or more user equipment, and an Ethernet topology comprising a master node and one or more slave nodes. The device is configured to receive, from the master node, an Ethernet frame comprising a header and a payload, wherein the payload comprises data of the one or more slave nodes, to segment the Ethernet frame into a header unit and multiple data units, based on context information, wherein each data unit comprises data of a respective slave node; and to transmit each data unit with the header unit to a further device of the wireless communication network to be forwarded to the respective slave node.

Description

DEVICE AND METHOD FOR PROCESSING ETHERNET-RASED TRAFFIC

TECHNICAL FIELD

The present disclosure relates to a data processing method, and in particular, to a context- based data segmentation, association and prioritization of Ethernet-based traffic. A device and user equipment (UE) both for supporting Ethernet protocols in wireless communication networks is disclosed.

BACKGROUND

5G new radio (5G NR) system will extend its application to cover communication for automation in industries, in which industrial Ethernet needs to be integrated with or even replaced by wireless communication. Most of the industrial Ethernet protocols require strict communication requirements that include cyclic and deterministic data transmission with very low latency and low jitter between different parts of the automation system.

Seamless integration of 5G system with industrial communication faces many challenges. For example, it is very challenging to fulfill the strict industrial Ethernet protocol requirements with respect to cycle time and jitter without efficient mapping of the industrial Ethernet data/frames into 5G NR protocol stack.

The cyclic periodic traveling frame (summation frame) structure is associated with a ring, star and line topology of some of the industrial Ethernet protocols such as Ethernet for control automation technology (EtherCAT) and serial real-time communication system (SERCOS). Such a frame structure cannot be supported directly by a 5G system due to the unique on-the-fly processing, which in turn affects the resource efficiency and strict latency in 5G NR. Since the frame structure contains data of all nodes, those data need to travel to all the nodes in the given topology. The UE or the network needs to unnecessarily decode and forward the entire frame structure. This results in a high bandwidth usage, high processing power, and high latencies. As shown in FIG. 1, EtherCAT uses the concept of a summation frame. In particular, data of all nodes are structured in a single frame traveling through all nodes. There are one common Ethernet header, and n subheaders for n nodes in the given EtherCAT frame. Each node adjusts the timing (synchronization) based on the previous node and only accesses its own data in a certain time slot. To realize such a topology with 5G NR, device to device (D2D) communication is required in order to receive the frame from one node and forward it to the next node. This requires each UE to receive, decode, encode and transmit the entire frame to the next UE. Consequently, a high power consumption and high bandwidth is required.

The need for extending Ethernet protocol, in particular industrial Ethernet protocol, with wireless communications has been already studied during the last decade. Most of the current solutions are based on introducing a gateway between e.g. EtherCAT master node and slave nodes. Such a gateway is used as an adaptation layer to convert between EtherCAT and e.g. wireless Zigbee. However, there are no available solutions for replacing the wired communication between nodes with LTE or 5G systems at present.

SUMMARY Embodiments of the present invention aim to provide a solution for extending Ethernet protocols with wireless communication systems, for example with LTE or 5G systems, in particular, for replacing the wired communication between nodes with a wireless communication. An objective is to reduce a latency and also increase an efficiency of a communication process.

The objective is achieved by the embodiment provided in the enclosed independent claims. Advantageous implementations of the embodiments of the present invention are further defined in the dependent claims. A first aspect of the invention provides a device for a wireless communication network, the wireless communication network comprising a core network device, a base station, one or more UEs, and an Ethernet topology comprising a master node and one or more slave nodes, wherein the device is configured to: receive, from the master node, an Ethernet frame comprising a header and a payload, wherein the payload comprises data of the one or more slave nodes; segment the Ethernet frame into a header unit and multiple data units, based on context information , wherein each data unit comprises data of a respective slave node; transmit each data unit with the header unit to a further device of the wireless communication network to be forwarded to the respective slave node.

The Ethernet topology may be the star topology or the ring topology as shown in FIG. 1. A device of the wireless communication network, receives an Ethernet frame from the master node of the Ethernet topology. In a typical industrial Ethernet Frame structure, e.g. EtherCAT frame, there are one common Ethernet header, n subheaders for n nodes, and n node specific datagrams, as depicted in FIG. 1. The Ethernet frame containing data of all slave nodes of the Ethernet topology, is segmented into a number of datagrams. In this way, the slave node is allowed to only receive the relevant data. Thus, a bandwidth usage, processing power, and latency are reduced.

In an implementation form of the first aspect, the context information comprises one or more of the following information: topology information of the master node and the one or more slave nodes; an order number of the one or more slave nodes; and Ethernet protocol information regarding common header locations, subheaders of the data of the respective slave node, information elements and a payload size of the data of the respective slave node.

The context information is received by the 5G core network (5GC), e.g. application function (AF). The context information is further processed by the 5GC into radio access network (RAN) relevant information, to provide a basis for the segmentation.

In an implementation form of the first aspect, the device is configured to: associate each data unit with an indicator; and assign a priority for each data unit, wherein the indicator and the priority are determined based on the context information.

Priority for the traffic is assigned during protocol data unit (PDU) session establishment and mapped to a 5G quality of server (QoS) indicator (5QI).The 5QI is assigned per QoS flow and is used by the RAN for traffic prioritization and scheduling. In an implementation form of the first aspect, the device is configured to: map each data unit to a time-frequency resource allocated to the UE connected with the respective slave node, based on a mapping table.

Media access control (MAC) layer of the RAN maps the corresponding segments, i.e. data units after the segmentation, to the physical resources assigned to each UE. In particular, each UE may be connected with one or more slave nodes.

In an implementation form of the first aspect, the context information further comprises the mapping table between logical address of the respective slave node and an identifier of the UE.

In particular, each UE may be connected to one or more slaves with distinct logical address. The mapping table, that translates the logical address of the slaves (configured logical address or MAC address) to that of UE identifiers, may be shared with the RAN as part of context information.

In an implementation form of the first aspect, the device is the base station and the further device is one of the UE connected to the respective slave node.

This invention proposes a RAN-based segmentation. That means, at radio link control layer (RLC) layer of the RAN, the frame is segmented based on the context information into node specific PDUs. Accordingly, data belongs to a certain node is sent to the corresponding UE connected to the node.

In an implementation form of the first aspect, the device is configured to: obtain the context information from the core network device.

The procedure of supporting Ethernet protocol starts with information sharing between Ethernet applications and 5GC. The 5GC further exchanges the context information with RAN, e.g. via a 5GC/BS interface (N2).

In an implementation form of the first aspect, the device is configured to: multicast the header unit to all UE connected with the one or more slave nodes. The common Ethernet headers may be mapped to a multicast channel (MCCH), since they are common for all slave nodes.

In an implementation form of the first aspect, the device is configured to: unicast each data unit to a UE connected with the respective slave node.

Node specific data may be mapped to different dedicated traffic channels (DTCHs).

In an implementation of the first aspect, the device is the core network device and the further device is the base station adapted to forward the header unit and each data unit to a UE connected to the respective slave node.

Alternatively, this invention also proposes a user plane function (UPF) based segmentation. Namely, the segmentation may also be done at the 5GC, e.g. at UPF layer. Particularly, 5GC has the context information required for segmenting the Ethernet frame. The segments can be sent to the RAN, where the RAN further forwards the segments to the UEs connected with the respective slave nodes.

In an implementation of the first aspect, the context information further comprises a QoS requirement of the data.

Based on the shared context information from 5GC, the data/traffic can be categorized into different types based on the different QoS requirements. The segmentation separates the data based on the types.

A second aspect of the invention provides a UE for a wireless communication network comprising a core network device, a base station, one or more UE, and an Ethernet topology comprising a master node and one or more slave nodes, wherein the UE is configured to: receive, from the base station, a header unit and one or more data units, wherein each data unit comprises data of a respective slave node connected with the UE; construct an Ethernet frame for each slave node, from the received header unit and one or more data unit of the respective slave node, based on context information and timing information, wherein the Ethernet frame comprises a header and a payload, wherein the payload comprises data of the respective slave node; transmit the Ethernet frame to the respective slave node.

In order to support Ethernet protocols in wireless communications, UE receives data units from the RAN. Particularly, the UE only receives the data units that relevant to slave nodes connected with the UE. Further, an Ethernet frame reconstruction procedure is performed at the UE side, based on the context information and timing information.

In an implementation of the second aspect, the context information comprises one or more of the following information: topology information of the master node and the one or more slave nodes; an order number of the one or more slave nodes; and Ethernet protocol information regarding common header locations, subheaders of the data of the respective slave node, information elements and a payload size of the data of the respective slave node.

In an implementation of the first aspect, the UE is configured to: concatenate the header unit, one or more data unit of the respective slave node, and blank bits, to obtain the Ethernet frame, wherein the header unit is inserted in the header, the one or more data unit of the respective slave node is inserted in time slots allocated to the respective slave node in the payload, and blank bits are filled in the rest of time slots in the payload.

At the UE side, the Ethernet frame, e.g. EtherCAT frame, is reconstructed back. The UE receives its own data on the corresponding resources, maps the decoded data to a summation frame, and keeps the slots that correspond to other nodes empty, then send the entire frame to the slave device connected with the UE.

In an implementation of the first aspect, the UE is configured to: obtain the context information and timing information from the base station.

The RAN may share the context information and timing information with the UE.

In an implementation of the first aspect, the header unit and the one or more data units are forwarded by the base station from the core network device. In case that the segmentation is performed in 5GC, the base station may forward the segmented data to the UE.

A third aspect of the invention provides a method for a wireless communication network comprising a core network device, a base station, one or more UE, and an Ethernet topology comprising a master node and one or more slave nodes, the method comprising: receiving, from the master node, an Ethernet frame comprising a header and a payload, wherein the payload comprises data of the one or more slave nodes; segmenting the Ethernet frame into a header unit and multiple data units, based on context information, wherein each data unit comprises data of a respective slave node; transmitting each data unit with the header unit to a further device of the wireless communication network to be forwarded to the respective slave node.

The method of the third aspect may have implementation forms that correspond to the implementation forms of the device of the first aspect. The method of the third aspect and its implementation forms provide the same advantages and effects as described above for the device of the first aspect and its respective implementation forms.

A fourth aspect of the invention provides a method for a wireless communication network comprising a core network device, a base station, one or more UE, and an Ethernet topology comprising a master node and one or more slave nodes, the method comprising: receiving, from the base station, a header unit and one or more data units, wherein each data unit comprises data of a respective slave node connected with the UE; constructing an Ethernet frame for each slave node from the received header unit and one or more data unit of the respective slave node, based on context information and timing information, wherein the Ethernet frame comprises a header and a payload, wherein the payload comprises data of the respective slave node; transmitting the Ethernet frame to the respective slave node.

The method of the fourth aspect may have implementation forms that correspond to the implementation forms of the UE of the second aspect. The method of the fourth aspect and its implementation forms provide the same advantages and effects as described above for the UE of the second aspect and its respective implementation forms. To summarize, an adaptation layer to the 5G system for supporting industrial Ethernet protocols is provide by embodiments of the invention. The adaptation layer can be introduced at 5G core network, or at the 5G RAN / next generation RAN (NG RAN), particularly at the RLC of the RAN. This invention proposes to segment or concatenate traditional RLC service data units (SDUs) received from the upper layer (e.g., packet data convergence protocol (PDCP)) to RLC PDUs, according to the layer transport block size (TBS) determined by the MAC layer, and send the PDUs to MAC. The procedure of supporting Ethernet protocols starts with information sharing between Ethernet applications (master node) and 5GC. In addition, these information is also shared with RAN.

It has to be noted that all devices, elements, units and means described in the present application could be implemented in the software or hardware elements or any kind of combination thereof. All steps which are performed by the various entities described in the present application as well as the functionalities described to be performed by the various entities are intended to mean that the respective entity is adapted to or configured to perform the respective steps and functionalities. Even if, in the following description of specific embodiments, a specific functionality or step to be performed by external entities is not reflected in the description of a specific detailed element of that entity which performs that specific step or functionality, it should be clear for a skilled person that these methods and functionalities can be implemented in respective software or hardware elements, or any kind of combination thereof.

BRIEF DESCRIPTION OF DRAWINGS

The above described aspects and implementation forms of the present invention will be explained in the following description of specific embodiments in relation to the enclosed drawings, in which

FIG. 1 shows a summation frame structure (top) in industrial networks within a star topology (left) and a ring topology (right).

FIG. 2 shows a device according to an embodiment of the invention. FIG. 3 shows a context information sharing between 5GC and RAN according to an embodiment of the invention.

FIG. 4 shows a context-based segmentation of Ethernet frame at the RLC according to an embodiment of the invention.

FIG. 5 shows a data association and prioritization for segmented PDUs according to an embodiment of the invention. FIG. 6 shows a frame mapping at MAC according to an embodiment of the invention.

FIG. 7 shows a mapping table of UEs and slave nodes according to embodiments of the invention.

FIG. 8 shows a segmentation done at 5G-C (UPF) according to an embodiment of the invention.

FIG. 9 shows supporting different types of traffic according to an embodiment of the invention.

FIG. 10 shows a UE according to an embodiment of the invention.

FIG. 11 shows an Ethernet frame reconstruction at UE side according to an embodiment of the invention.

FIG. 12 shows a signaling chart of Ethernet frame segmentation information sharing according to an embodiment of the invention. FIG. 13 shows a schematic block flowchart of a method according to an embodiment of the invention.

FIG. 14 shows a schematic block flowchart of another method according to an embodiment of the invention. DETAILED DESCRIPTION OF EMBODIMENTS

FIG. 2 shows a device 200 for supporting Ethernet protocols in a wireless communication network according to an embodiment of the invention. The device 200 may comprise processing circuitry (not shown) configured to perform, conduct or initiate the various operations of the device 200 described herein. The processing circuitry may comprise hardware and software. The hardware may comprise analog circuitry or digital circuitry, or both analog and digital circuitry. The digital circuitry may comprise components such as application-specific integrated circuits (ASICs), field-programmable arrays (FPGAs), digital signal processors (DSPs), or multi-purpose processors. In one embodiment, the processing circuitry comprises one or more processors and a non-transitory memory connected to the one or more processors. The non-transitory memory may carry executable program code which, when executed by the one or more processors, causes the device 200 to perform, conduct or initiate the operations or methods described herein.

In particular, the device 200 is in a wireless communication network 300 (not shown in FIG. 2, see FIG. 7). In particular, the wireless communication network 300 comprises a core network device 301, a base station 302, and one or more UEs 303. The device 200, according to an embodiment of the invention, may be one of the core network device 301 and the base station 302. The device 200, according to an embodiment of the invention, is connected to an Ethernet topology 100 comprising a master node 101 and one or more slave nodes 102. The Ethernet topology 100 may be the star topology, or the ring topology as shown in FIG. 1. In a conventional Ethernet topology, a frame that contains data of all nodes, may be sent in a ring (as the left topology of FIG. 1). Each node decodes and forwards the entire frame.

The device 200 is configured to receive, from the master node 101, an Ethernet frame 201 comprising a header and a payload, wherein the payload comprises data of the one or more slave nodes 102. The device 200 is further configured to segment the Ethernet frame 201 into a header unit 202 and multiple data units 203, based on context information, wherein each data unit 203 comprises data of a respective slave node 102. The device 200 is further configured to transmit each data unit 203 with the header unit 202 to a further device 304 of the wireless communication network 300 to be forwarded to the respective slave node 102.

The Ethernet frame 201 may be the EtherCAT frame as shown on the top of FIG. 1. In particular, the Ethernet frame 201 may comprise Ethernet common headers (e.g. including Ethernet header and EtherCAT header), process data object (PDO) headers for each node (e.g. HDR1, HDR2... HDR5), and node specific datagrams (e.g. N1, N2... N5), as depicted in FIG. 1. Notably, data in each sub-datagram is intended for a specific node and independent of other sub-datagrams.

This invention proposes to segment a received common Ethernet-based frame into multiple node specific PDUs according to the destination of the PDUs. Accordingly, segmented PDUs should be sent to different nodes depending on the destination. The further device 304 is enabled to forward segmented PDUs to the respective slave node 102 of the Ethernet topology 100. Particularly, the further device 304 may be one of UE 303 (not shown in FIG. 2, see FIG. 7 and FIG. 10). In other scenario, the further device 304 may be the base station 302, and may forward segmented PDUs to the respective UE 303, which connected with the respective slave nodes 102.

In some embodiments of this invention, the device 200 may be the base station 302. In such case, a RAN-base segmentation is performed. Accordingly, the further device 304 according to these embodiments of the invention may be one of the UE 303 connected with the respective slave node 102 (see FIG. 7). Notably, same elements in the figures are labeled with the same reference signs and function likewise.

Optionally, the device 200, i.e. the base station 302, may be configured to obtain the context information from the core network device 301. Sharing of the context information between 5GC and RAN allows the RAN, i.e. the base station 302, to perform the context based segmentation and scheduling. The context information may be received by the core network device 301, for instance from an Ethernet application controller (maser node). The procedure of supporting Ethernet protocols may start with information sharing between Ethernet applications and 5GC. The 5GC further processes the context information into RAN-relevant information, such as RLC segment offsets, segment lengths, bearer IDs/QoS Flow IDs, and priorities. Such information provide a basis for the segmentation and scheduling.

As shown in FIG. 3, 5G core network and BS interface exchange the context information with RAN. In particular, according to an embodiment of the invention, the core network device 301 and the base station 302 exchange topology information including how the nodes are connected and the order of the nodes, number of connected nodes, industrial Ethernet protocol information regarding common header locations, subheader, information elements and payload sizes. It should be noted that, FIG. 3 - FIG. 6 may show the same core network device 301, and the same base station 302.

According to an embodiment of the invention, the context information may comprise one or more of the following information: topology information of the master node 101 and the one or more slave nodes 102; an order number of the one or more slave nodes 102; and Ethernet protocol information regarding common header locations, subheaders of the data of the respective slave node 102, information elements and a payload size of the data of the respective slave node 102.

At RLC layer of the base station 302, the Ethernet frame 201 is segmented based on the context information (number of the nodes, the topology, etc.) into node specific PDUs as described in FIG. 4. In particular, based on the type of the individual data, the segmented PDUs are mapped to different logical channels. For example, the common Ethernet header will be mapped to a multicast channel as shown in FIG. 4, since it is common for all UEs or all nodes. Node specific data will be mapped to different unicast data channels, e.g. different DTCHs as depicted in FIG. 4.

Further, after the segmentation, the device 200 according to an embodiment of the invention, may be configured to associate each data unit 203 with an indicator; and assign a priority for each data unit 203, wherein the indicator and the priority are determined based on the context information.

As shown in FIG. 5, according to an embodiment of the invention, at MAC layer of the base station 302, segmented PDUs are associated with a common SDU (Ethernet frame) with a data association indicator (DAI). In addition, relative priorities for segmented PDUs are assigned based on the context information. In particular, the context information may comprise topology information and timing requirements. RLC services may provide association information of PDUs across the one or more UEs. And priorities of RLC PDUs within an association group may also be provided by the RLC services.

PIG. 6 further shows a frame mapping at MAC, according to an embodiment of the invention. Priorities and association of RLC PDUs may be considered for node scheduling and frame mapping. Preferably, prioritization of Ethernet sub-datagrams, e.g. Nl, N2... 5 as shown in the Ethernet frame 201 of PIG. 6, are performed based on traffic classes of the sub-datagrams. Data association may be performed based on whether the PDUs belong to the same Ethernet frame.

It can be seen that, a common header may be multicast via a physical downlink shared channel (PDCCH), and mapped for example into a common downlink control indicator (DCI) frame. The common Ethernet header, particularly the header unit 202, may be multicast via a physical multicast channel (PMCH), as depicted in FIG. 6. Thus, optionally, the device 200 according to an embodiment of the invention, may be configured to multicast the header unit 202 to all UEs 303 connected with the one or more slave nodes 102.

Further, the device 200, according to an embodiment of the invention, may be configured to unicast each data unit 203 to a UE 303 connected with the respective slave node 102. That means, data units 203 of the respective slave node 102, are mapped accordingly, for instance, based on the destination of the data units 203. Possibly, the data units 203 which belong to the same slave node 102, are mapped into continuous subframes, as shown in FIG. 6.

Accordingly, the device 200 according to an embodiment of the invention, may be further configured to map each data unit 203 to a time-frequency resource allocated to the UE 303 connected with the respective slave node 102, based on a mapping table.

The mapping table that translates the logical address of the slave nodes (configured logical address or MAC address) to that of UE identifiers, is shared with the RAN as part of the context information. According to an embodiment of the invention, each UE 303 may be connected to one or more slave nodes 102 with distinct logical address, as depicted in the table shown in FIG. 7. Change in order of node specific packet arrival in the travelling frame structure of the industrial protocol could be detected and can be associated with the corresponding UE identifiers.

Optionally, the context information further comprises the mapping table between logical address of the respective slave node 102 and an identifier of the UE 303. Particularly, the mapping table is the table shown in FIG. 7. According to a network structure shown in FIG. 7, the one or more UEs 303, i.e. UE1, UE2 and/or UE3, belong to a wireless communication network 300. 5G as shown in FIG. 7, represents for example a 5GC and/or RAN, which communicates with a Master, i.e. the master node 101 in an Ethernet topology 100. In particular, UE1 is connected with one slave node, i.e. Slave 1; UE2 is connected with Slave 2, Slave 3 and Slave 4; and UE3 is connected with Slave 5, as shown in the network structure of FIG. 7.

Further, in other embodiments of the invention, alternatively the device 200 can be the core network device 301. In such case, a UPF-base segmentation is performed as shown in FIG. 8. Accordingly, the further device 304 according to these embodiments of the invention may be the base station 302.

The UPF is a fundamental component of a 5G core infrastructure system architecture. As shown in FIG. 8, an incoming Ethernet frame is received by the core network device 301. An Ethernet packet filter set may be extended to include node specific segmentation information. Mapping of segmented traffic to corresponding PDU identifier (PDU ID) / dedicated radio bearer (DRB) ID, may be done based on a DAI in the UPF. It should be noted that, the segmentation, data association, prioritization, and bearer/frame mapping procedures are similar as performed at the RLC-based segmentation embodiments of the invention. These procedures can be performed at a core network device, and also a RAN device.

Optionally, the context information may further comprise a QoS requirement of the data.

As shown in FIG. 9, based on the shared context information from 5GC, the data can be categorized into different types based on the QoS requirements, e.g. non- real time (NRT), real time (RT), and isochronous real time (IRT) data traffic. RLC segmentation separates the data based on type, and the MAC layer applies optimal scheduling in terms of physical numerologies availability.

FIG. 10 shows a UE 303 according to an embodiment of the invention. The UE 303 may be one of the UE 303 as shown in FIG. 7. In particular, a wireless communication network 300 comprises a core network device 301, a base station 302, and one or more UE 303. The core network device 301, may be the same core network device 301 as shown in FIG. 3 - FIG. 6. The base station 302 shown in FIG. 10 may be the same base station 302 as shown in FIG. 3 - FIG. 6. An Ethernet topology 100 comprises a master node 101 and one or more slave nodes 102, wherein the UE 303 according to an embodiment of the invention is connected with one or more slave nodes 102. In particular, the Ethernet topology 100 may be one of the topologies as shown in FIG. 1. The slave node 102 as shown in FIG. 10 may be one of the slave node shown in FIG. 1, or FIG. 7.

The UE 303 may be configured to: receive, from the base station 302, a header unit 202 and one or more data units 203. In particular, each data unit 203 comprises data of a respective slave node 102 connected with the UE 303. For instance, if the UE 303 is the UE2 as shown in FIG. 7, three slave nodes are connected with this UE 303. Thus, data units 203 received by the UE 303 may comprise data units of Slave 2, Slave 3 and Slave 4 in this embodiment. In another example, if the UE 303 is the UE3 as shown in FIG. 7, possibly only data units of Slave 5 are received by this UE 303.

Further, the UE 303, according to an embodiment of the invention, may be configured to construct an Ethernet frame 201 for each slave node 102, from the received header unit 202 and one or more data unit 203 of the respective slave node 102, particularly based on context information and timing information. The Ethernet frame 201 comprises a header and a payload, wherein the payload comprises data of the respective slave node 102. The UE 303 may be further configured to transmit the Ethernet frame 201 to the respective slave node 102. Notably, the Ethernet frame 201 shown in FIG. 10 may have a similar structure as the Ethernet frame 201 as shown in FIG. 1 - FIG. 6, and FIG. 8. However, the Ethernet frame 201 shown in FIG. 10 comprises only data units relevant to one slave node. According to an embodiment of the invention, the context information may comprise one or more of the following information: topology information of the master node 101 and the one or more slave nodes 102; an order number of the one or more slave nodes 102; and Ethernet protocol information regarding common header locations, subheaders of the data of the respective slave node 102, information elements and a payload size of the data of the respective slave node 102.

Optionally, the RAN may share the context information with the UE side. Thus, the UE 303 according to an embodiment of the invention, may be configured to obtain the context information and timing information from the base station 302.

Based on the obtained context information, the UE 303 may be configured to concatenate the header unit 202, one or more data unit 203 of the respective slave node 201, and blank bits, to obtain the Ethernet frame 201. In particular, the header unit 202 may be inserted in the header of the Ethernet frame 201, the one or more data unit 203 of the respective slave node 102 is inserted in time slots allocated to the respective slave node 102 in the payload of the Ethernet frame 201. In addition, blank bits are filled in the rest of time slots in the payload. As shown in FIG. 11, according to an embodiment of the invention, the Ethernet frame 201 for slave node N1 comprises the common Ethernet header and data units of slave node Nl. It can be seen that, the rest time slots in the payload, i.e. allocated for other slave nodes, are empty.

It should be understood that, a service data adaptation protocol (SDAP) layer or a RLC layer at the UE side reconstructs the Ethernet frame 201 by concatenating the common header with node specific data. In addition, since the slave node expects its data at a certain location, blank (filler bits) are inserted into the reconstructed Ethernet frame representing data of other slaves.

In some embodiments, the UE 303 shown in FIG. 10 may the further device 304 as shown in FIG. 2. In such case, the context-based segmentation is done at RAN. That means, the base station 302 segments an Ethernet frame received from a master node.

In other alternative embodiments, the header unit 202 and the one or more data units 203 received by the UE 303, are forwarded by the base station 302 from the core network device 301. Namely, the context-based segmentation is done at 5GC. The RAN acts as a forwarding node in such scenario.

FIG. 12 shows a signaling for Ethernet frame segmentation information sharing according to an embodiment of the invention. In particular, the UE 303 shown in FIG. 12 is the UE 303 as shown in FIG. 10. The base station 302 shown in FIG. 12 is the device 200 as shown in FIG. 2 and/or the base station 302 as shown in FIG. 3 - FIG. 6. The core network device 301 shown in FIG. 12 is the core network device 301 as shown in FIG. 3 6

In order to support Ethernet protocols in wireless communication network, a RAN-based segmentation is performed. The new functionality added in the RLC layer of RAN, e.g. gNB, reads context information from 5GC about the frame structure, offsets, traffic types, etc. These information is stored in RAN, and may be further shared with the UE side. After a PDU session is established, the RAN converts RLC SDU to node specific RLC PDUs, particularly based on the context information. Specifically, these PDUs are sub-Ethernet packets which are transparently segmented (namely, a programmable logic controller (PLC) master is not aware of the segmentation) and mapped into logical data channels (e.g. DTCHs) containing different radio bearers, while the common headers are mapped to MCCH logical channel which could be multicast to all nodes. In particular, the data mapped to different radio bearers are scheduled with unicast transmission while common headers are multicast. Logical address of the node is associated with that of DRB ID and UE ID in RAN. Further, indication of order priority of RLC PDUs for orderly scheduling is provided to lower layers, for instance, on how the nodes are connected to each other which is can be used by the scheduler. Services such as associating RLC PDUs across UEs, and priorities of RLC PDUs within an association group, are also provided to lower layers.

The UE side, i.e. the UE 303, performs an Ethernet frame reconstruction as discussed in the embodiment shown in FIG. 11. In this way, data from master node to slave nodes and back, is sent in independent frames (unicast). Each UE decodes only its own data. Consequently, a latency reduction is obtained with efficient context-based segmentation procedure. According to embodiments of the invention, a spectral efficiency is also obtained with each UE does not unnecessarily need to decode and forward entire Ethernet frame to other UEs. It should be noted that, for the RAN-based segmentation, the uplink data from all UEs need to be concatenated at RLC layer to build the original EtherCAT frame. Then the reconstructed EtherCAT frame can be forwarded to the application (master) via the core network.

FIG. 13 shows a method 1300 for a wireless communication network 300 comprising a core network device 301, a base station 302, one or more UE 303, and an Ethernet topology 100 comprising a master node 101 and one or more slave nodes 102, according to an embodiment of the present invention. In particular, the method 1300 is performed by a device 200 in the wireless communication network 300 as shown in FIG. 2. The method 1300 comprises a step 1301 of receiving, from the master node 101, an Ethernet frame 201 comprising a header and a payload, wherein the payload comprises data of the one or more slave nodes 102; a step 1302 of segmenting the Ethernet frame 201 into a header unit 202 and multiple data units 203, based on context information, wherein each data unit 203 comprises data of a respective slave node 102; and a step 1303 of transmitting each data unit 203 with the header unit 202 to a further device 304 of the wireless communication network 300 to be forwarded to the respective slave node 102.

FIG. 14 shows a method 1400 for a wireless communication network 300 comprising a core network device 301, abase station 302, one or more UE 303, and an Ethernet topology 100 comprising a master node 101 and one or more slave nodes 102, according to an embodiment of the present invention. In particular, the method 1300 is performed by a UE 303 in the wireless communication network 300 as shown in FIG. 10. The method 1400 comprises: a step 1401 of receiving, from the base station 302, a header unit 202 and one or more data units 203, wherein each data unit 203 comprises data of a respective slave node 102 connected with the UE 303; a step 1402 of constructing an Ethernet frame 201 for each slave node from the received header unit 202 and one or more data unit 203 of the respective slave node 102, based on context information and timing information, wherein the Ethernet frame 201 comprises a header and a payload, wherein the payload comprises data of the respective slave node 102; and a step 1403 of transmitting the Ethernet frame 201 to the respective slave node 102. The present invention has been described in conjunction with various embodiments as examples as well as implementations. However, other variations can be understood and effected by those persons skilled in the art and practicing the claimed invention, from the studies of the drawings, this disclosure and the independent claims. In the claims as well as in the description the word“comprising” does not exclude other elements or steps and the indefinite article“a” or“an” does not exclude a plurality. A single element or other unit may fulfill the functions of several entities or items recited in the claims. The mere fact that certain measures are recited in the mutual different dependent claims does not indicate that a combination of these measures cannot be used in an advantageous implementation.

Claims

1. Device (200) for a wireless communication network (300), the wireless communication network (300) comprising a core network device (301), a base station (302), one or more user equipment (303), and an Ethernet topology (100) comprising a master node (101) and one or more slave nodes (102), wherein the device (200) is configured to:

receive, from the master node (101), an Ethernet frame (201) comprising a header and a payload, wherein the payload comprises data of the one or more slave nodes (102); segment the Ethernet frame (201) into a header unit (202) and multiple data units (203), based on context information, wherein each data unit (203) comprises data of a respective slave node (102); and

transmit each data unit (203) with the header unit (202) to a further device (304) of the wireless communication network (300) to be forwarded to the respective slave node (102).

2. The device (200) according to claim 1, wherein

the context information comprises one or more of the following information: topology information of the master node (101) and the one or more slave nodes

(102);

an order number of the one or more slave nodes (102); and

Ethernet protocol information regarding common header locations, subheaders of the data of the respective slave node (102), information elements and a payload size of the data of the respective slave node (102).

3. The device (200) according to claim 1 or 2, configured to:

associate each data unit (203) with an indicator; and

assign a priority for each data unit (203),

wherein the indicator and the priority are determined based on the context information.

4. The device (200) according to claim 3, configured to:

map each data unit (203) to a time-frequency resource allocated to the user equipment (303) connected with the respective slave node (102), based on a mapping table.

5. The device (200) according to claim 4, wherein:

the context information further comprises the mapping table between logical address of the respective slave node (102) and an identifier of the user equipment (303).

6. The device (200) according to one of the claims 1 to 5, wherein

the device (200) is the base station (302) and the further device (304) is one of the user equipment (303) connected to the respective slave node (102).

7. The device (200) according to claim 6, configured to:

obtain the context information from the core network device (301).

8. The device (200) according to claim 6 or 7, configured to:

multicast the header unit (202) to all user equipment (303) connected with the one or more slave nodes (102).

9. The device (200) according to one of the claims 6 to 8, configured to:

unicast each data unit (203) to a user equipment (303) connected with the respective slave node (102).

10. The device (200) according to one of the claims 1 to 5, wherein

the device is the core network device (301) and the further device (304) is the base station (302) adapted to forward the header unit (202) and each data unit (203) to a user equipment (303) connected to the respective slave node (102).

11. The device (200) according to one of the claims 1 to 10, wherein

the context information further comprises a quality of service requirement of the data.

12. User equipment (303) for a wireless communication network (300) comprising a core network device (301), a base station (302), one or more user equipment (303), and an Ethernet topology (100) comprising a master node (101) and one or more slave nodes (102), wherein the user equipment (303) is configured to:

receive, from the base station (302), a header unit (202) and one or more data units (203), wherein each data unit (203) comprises data of a respective slave node (102) connected with the user equipment (303);

construct an Ethernet frame (201) for each slave node (102), from the received header unit (202) and one or more data unit (203) of the respective slave node (102), based on context information and timing information, wherein the Ethernet frame (201) comprises a header and a payload, wherein the payload comprises data of the respective slave node (102); and

transmit the Ethernet frame (201) to the respective slave node (102).

13. The user equipment (303) according to claim 12, wherein

(102);

an order number of the one or more slave nodes (102); and

14. The user equipment (303) according to claim 12 or 13, configured to:

concatenate the header unit (202), one or more data unit (203) of the respective slave node (201), and blank bits, to obtain the Ethernet frame (201),

wherein the header unit (202) is inserted in the header, the one or more data unit (203) of the respective slave node (102) is inserted in time slots allocated to the respective slave node (102) in the payload, and blank bits are filled in the rest of time slots in the payload.

15. The user equipment (303) according to one of the claims 12 to 14, configured to: obtain the context information and timing information from the base station (302).

16. The user equipment (303) according to one of the claims 12 to 15, wherein the header unit (202) and the one or more data units (203) are forwarded by the base station (302) from the core network device (301).

17. Method (1300) for a wireless communication network (300) comprising a core network device (301), a base station (302), one or more user equipment (303), and an Ethernet topology (100) comprising a master node (101) and one or more slave nodes (102), the method (1300) comprising:

receiving (1301), from the master node (101), an Ethernet frame (201) comprising a header and a payload, wherein the payload comprises data of the one or more slave nodes (102);

segmenting (1302) the Ethernet frame (201) into a header unit (202) and multiple data units (203), based on context information, wherein each data unit (203) comprises data of a respective slave node (102); and

transmitting (1303) each data unit (203) with the header unit (202) to a further device (304) of the wireless communication network (300) to be forwarded to the respective slave node (102).

18. The method (1400) for a wireless communication network (300) comprising a core network device (301), a base station (302), one or more user equipment (303), and an Ethernet topology (100) comprising a master node (101) and one or more slave nodes (102), the method (1400) comprising:

receiving (1401), from the base station (302), a header unit (202) and one or more data units (203), wherein each data unit (203) comprises data of a respective slave node (102) connected with the user equipment (303);

constructing (1402) an Ethernet frame (201) for each slave node from the received header unit (202) and one or more data unit (203) of the respective slave node (102), based on context information and timing information, wherein the Ethernet frame (201) comprises a header and a payload, wherein the payload comprises data of the respective slave node (102); and

transmitting (1403) the Ethernet frame (201) to the respective slave node (102).