Integrated TSN and 5g system

Abstract

To provide a method of transmitting data between a time-sensitive networking (TSN) system and a 5G network.SOLUTION: A method comprises receiving, from a TSN system, data comprising a plurality of frames, defining k disjoint paths when k≥2, and for each frame of the data, performing at least one of the processes (a) and (b). In the process (a), the method includes transmitting k copies of the frame to a transmission destination via the disjoint paths, determining, based on a redundancy policy indicating a protocol for deleting redundant copies, whether one or more of the k copies received at the transmission destination are redundant and eliminating the copies determined to be redundant. In the process (b), the method includes generating, based on a redundancy policy of a 5G network indicating a protocol for replicating frames, copies of the frame, and transmitting the copies to a transmission destination via a respective one of the disjoint paths.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] TECHNICAL FIELD The embodiments described herein relate generally to communications, more particularly to wireless communications, and even more generally to communications in integrated TSN and 5G systems. [Background technology]

[0002] Time Sensitive Networking (TSN) is a technology backed by a set of standards within the IEEE 802.1 working group that aims to improve the real-time capabilities of standard Ethernet. TSN provides guaranteed data delivery with deterministic and bounded latency and extremely low data loss. TSN supports both time-critical and best-effort traffic over a single standard Ethernet network.

[0003] TSN will likely coexist with powerful wireless technologies such as 5G, and therefore the integration of TSN with 5G is desirable in the envisaged digital transformation of industrial systems.

[0004] One approach proposed in 3GPP Release 16 is a bridge model where the 5G system appears as a virtual TSN bridge or black box to the TSN system. The 5G system handles the TSN service requirements through its internal protocols and procedures. The 5G system provides (logical) ingress and egress ports to the TSN system. The 5G system may provide virtual bridge functionality to multiple TSN domains.

[0005] One of the standards in the IEEE 802.1 family is the 802.1CB standard, which provides fault tolerance to TSN systems through a frame replication and elimination for reliability (FRER) solution. FRER replicates each frame at the source over multiple paths and provides an elimination mechanism for redundant frames at the destination. An example protocol stack for FRER is shown in Figure 1.

[0006] Hereinafter, embodiments will be described with reference to the drawings. [Brief description of the drawings]

[0007] [Figure 1] A diagram showing a typical example of a FRER protocol stack. [Diagram 2] Diagram showing a typical example of a 5G core network architecture. [Diagram 3] A diagram showing the control plane protocol stack and user plane protocol stack in a 5G network. [Figure 4] FIG. 1 illustrates an example of an integrated communications network. [Diagram 5] FIG. 2 illustrates a further example of an integrated communications network. [Figure 6] FIG. 1 illustrates an example of a protocol data unit (PDU) session in a 5G network. [Figure 7] FIG. 1 shows an overall overview of three embodiments. [Figure 8] FIG. 2 illustrates a method according to a first embodiment. [Figure 9] FIG. 9 illustrates an example implementation of the method of FIG. 8. [Figure 10] FIG. 4 illustrates a method according to a second embodiment. [Figure 11] FIG. 11 illustrates an example implementation of the method of FIG. [Figure 12] FIG. 11 illustrates a method according to a third embodiment. [Figure 13]FIG. 13 illustrates an example implementation of the method of FIG. 12. [Figure 14] FIG. 13 illustrates a first variant of an exemplary implementation of the method of FIG. [Figure 15] FIG. 13 illustrates a second variant of an exemplary implementation of the method of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] According to one embodiment, there is provided a method of transmitting data between a Time Sensitive Networking (TSN) system and a 5G network, the method comprising: receiving data comprising a plurality of frames from the Time Sensitive Networking (TSN) system; defining k disjoint paths for transmitting the data across the 5G network, where k≧2; and for each frame of data, performing at least one of operations (a) and (b) by the 5G network, wherein in (a), transmitting k copies of the frame to a destination via respective ones of the disjoint paths; determining whether one or more of the transmitted k copies received at the destination are redundant based on a redundancy policy of the 5G network indicating a protocol for removing redundant copies of frames of TSN traffic and removing the copies determined to be redundant; while in (b), generating k copies of the frame based on a redundancy policy of the 5G network indicating a protocol for replicating frames of TSN traffic and transmitting the copies of the frame to the destination via respective ones of the disjoint paths.

[0009] In one embodiment, the method further comprises receiving, by the 5G network, scheduling information indicating time slots for reception of data in the 5G network.

[0010] In one embodiment, the 5G network comprises a first user equipment (UE) and a data network (DN), and defining the k disjoint multiple paths comprises establishing a connection between the first user equipment (UE) and the data network (DN).

[0011] In one embodiment, establishing the connection comprises establishing at least one protocol data unit (PDU) session for the first user equipment (UE).

[0012] In one embodiment, the 5G network further comprises a second user equipment (UE), and establishing the connection comprises establishing a first protocol data unit (PDU) session with the first user equipment (UE) and establishing a second protocol data unit (PDU) session with the second user equipment (UE).

[0013] In one embodiment, establishing the first protocol data unit (PDU) session comprises selecting a first user plane function (UPF) for the first protocol data unit (PDU) session, and establishing the second protocol data unit (PDU) session comprises selecting a second user plane function (UPF) for the second protocol data unit (PDU) session.

[0014] In one embodiment, at least one of (i) erasing copies determined to be redundant and (ii) generating k copies of the frame based on a redundancy policy of the 5G network indicating a protocol for replicating frames of TSN traffic is performed by a Data Network (DN) of the 5G network.

[0015] In one embodiment, establishing the connection comprises establishing a first protocol data unit (PDU) session with a first user equipment (UE) and establishing a second protocol data unit (PDU) session with the first user equipment (UE).

[0016] In one embodiment, a first protocol data unit (PDU) session is established via a first data network name (DNN) of the 5G network, and a second protocol data unit (PDU) session is established via a second data network name (DNN) of the 5G network.

[0017] In one embodiment, at least one of (i) clearing copies determined to be redundant and (ii) generating k copies of the frame based on a redundancy policy of the 5G network indicating a protocol for replicating frames of TSN traffic is performed by an Internet Protocol (IP) layer of the 5G network, by a User Plane Function (UPF) of the 5G network, or by a first user equipment (UE).

[0018] In one embodiment, establishing the connection comprises establishing, by a User Plane Function (UPF) of the 5G network, a first N3 tunnel and a second N3 tunnel for transmitting data over the 5G network.

[0019] In one embodiment, a first N3 tunnel connects a user plane function (UPF) and a master base station (MgNB), and a second N3 tunnel connects a user plane function (UPF) and a secondary base station (SgNB).

[0020] In one embodiment, at least one of (i) erasing copies determined to be redundant and (ii) generating k copies of the frame based on a redundancy policy of the 5G network indicating a protocol for duplicating frames of TSN traffic is performed by a GPRS Tunneling Protocol (GTP) layer of the 5G network.

[0021] In one embodiment, at least one of (i) erasing copies determined to be redundant and (ii) generating k copies of the frame based on a redundancy policy of the 5G network indicating a protocol for replicating frames of TSN traffic is performed by a layer of the 5G network's air interface protocol stack.

[0022] In one embodiment, the steps of (i) erasing copies determined to be redundant and (ii) generating k copies of the frame based on a redundancy policy of the 5G network indicating a protocol for replicating frames of TSN traffic are performed by a Service Data Adaptation Protocol (SDAP) layer of the 5G network.

[0023] In one embodiment, the steps of (i) erasing copies determined to be redundant and (ii) generating k copies of the frame based on a redundancy policy of the 5G network indicating a protocol for duplicating frames of TSN traffic are performed by a Packet Data Convergence Protocol (PDCP) layer of the 5G network.

[0024] According to one embodiment, a method is provided for transmitting data comprising a plurality of frames between a Time Sensitive Networking (TSN) system and a 5G network, the method comprising: for each frame of data, performing at least one of the following processes (c) and (d) by the Time Sensitive Networking (TSN) system, where (c) is obtaining k copies of the frame based on a redundancy policy of the 5G network indicating a protocol for duplicating frames of TSN traffic and a protocol for removing redundant copies of frames of TSN traffic, and sending the copies to a layer of the 5G network configured to erase the redundant copies of the frame based on the redundancy policy; and (d) is receiving the k copies of the frame from the 5G network, determining whether one or more of the received copies are redundant based on a redundancy policy of the 5G network indicating a protocol for removing redundant copies of frames of TSN traffic, and erasing the copies determined to be redundant.

[0025] In one embodiment, transmitting the copy comprises passing the received copy through with probability 1 / Θ, where Θ is the average number of paths available in the 5G network for TSN traffic.

[0026] In one embodiment, obtaining the k copies of the frame comprises replicating the received frame of data with probability 1 / Θ, where Θ is the average number of paths available in the 5G network for TSN traffic.

[0027] According to an embodiment, one or more non-transitory storage media are provided that include computer instructions executable by a processor, which, when executed by the processor, cause the processor to perform the above-mentioned method. The integration of TSN and 5G systems creates many challenges. The integrated operation of a heterogeneous network including TSN and 5G nodes is particularly difficult because the two technologies differ in functionality and internal protocols. Extending 802.1CB functionality to the integrated TSN and 5G system is particularly important when separate paths are not always available for end-to-end fault tolerance, in particular.

[0028] According to one embodiment, there is provided a device comprising a controller and a memory storing instructions executable by the controller, the instructions being configured, when executed, to cause the controller to perform any of the methods described above.

[0029] Figure 1 shows a typical example of a FRER protocol stack. The FRER protocol comprises two main mechanisms: (i) duplication of streams (via different paths) at the TSN talker (source node) and (ii) elimination of duplicates per stream at the relay node / TSN listener (destination node). The sequence generation function generates a sequence number for each frame of the stream. The stream splitting function generates M copies of each frame of the stream that are forwarded via M (distinct) separate paths. The sequence encoding function assigns the generated sequence number to each frame using the redundant tag (R-TAG) field of the Ethernet frame. The sequence decoding function extracts the sequence number from the received frame. The sequence recovery stage either accepts or discards the received frame. The sequence recovery function operates at the level of the composite stream, i.e., frames are received from all paths. The individual recovery function operates at the level of the member streams, i.e., frames are received from a single path. The stream identification function identifies the stream to which the frame belongs. Streams can be identified through source or destination MAC addresses or VLAN IDs in the Ethernet frame. Not all of the above features are included in all FRER protocol stacks.

[0030] Figure 2 shows a typical example of a 5G core network architecture. The network includes a user equipment (UE), a radio access network (RAN), a user protocol function (UPF), a data network (DN), a network exposure function (NEF), a network slice selection function (NSSF), a non-3GPP interworking function (N3IWF), an access and mobility management function (AMF), a unified data management function (UDM), a policy control function (PCF), a session management function (SMF), and an application function (AF). The radio access network (RAN) communicates with the user protocol function (UPF) via an N3 interface, and the user protocol function (UPF) communicates with the data network (DN) via an N6 interface. The access and mobility management function AMF communicates with the user equipment (UE) via an N1 interface and with the radio access network (RAN) via an N2 interface.

[0031] Figure 3 shows the control plane protocol stack and the user plane protocol stack in a 5G network. The control plane protocol stack includes a non-access stratum (NAS), a radio resource control layer (RRC), a packet data convergence protocol layer (PDCP), a radio link control layer (RLC), a medium access control layer (MAC), and a physical layer (PHY). The user plane protocol stack includes a service data adaptation protocol layer (SDAP), a packet data convergence protocol layer (PDCP), a radio link control layer (RLC), a medium access control (MAC), and a physical layer (PHY).

[0032] FIG. 4 shows an example of a converged communication network. The network comprises a plurality of TSN systems, each of which has an end station (ES). The end station (ES) may be a talker or a listener. The TSN system implements a FRER function. The network further includes a 5G system comprising at least one user equipment (UE), a radio access network (RAN) comprising one or more base stations (gNBs), and a core network. The 5G system communicates with each of the TSN systems via a virtual TSN bridge.

[0033] The converged network is managed by a centralized network configuration entity (CNC) that communicates with each of the multiple TSN systems and the 5G network.

[0034] 5 illustrates a further example of a converged communications network comprising two TSN systems A and B in communication with a 5G network and a number of further TSN systems 1...k in communication with TSN system A. Traffic from TSN system A may be transmitted to TSN system B via the 5G network. TSN systems A and B may provide FRER functionality and the 5G network may be configured to provide multipath transmission.

[0035] FIG. 6 shows an example of a protocol data unit (PDU) session in a 5G network. A PDU session serves to connect a user equipment (UE) to a particular data network. The PDU session may be an IP or Ethernet PDU session, and the establishment of the PDU session may be triggered by either the user equipment (UE) or another node of the 5G network. In the PDU session, two data radio bearers DRB1, DRB2 are established (in a variant of this example, one or more data radio bearers DRB are established in the PDU session). The 5G network further defines multiple quality of service data flows (QoS), each flow having a different QoS flow identifier QFI (QFI X, QFI Y, QFI Z) and mapped to one of the data radio bearers DRB1 and DRB2. Each of the QoS data flows is transmitted between a radio access network (RAN) and a user plane function (UPF) via the N3 interface of the 5G network.

[0036] 7 shows an overall overview of three embodiments (1) to (3). In each of the embodiments, a 5G network comprising at least one user equipment (UE) and at least one base station gNB is configured to receive and transmit TSN traffic. In the 5G network, the TSN traffic is received and transmitted via at least one protocol data unit session PDU and at least one user plane function (UPF).

[0037] In a first embodiment (1), a 5G network includes two user equipments UE1 and UE2, and is configured to establish a first PDU session (PDU session 1) connecting UE1 and a base station gNB, and a second PDU session (PDU session 2) connecting UE2 and a base station gNB. A first UPF (UPF1) is established for the first PDU session, and a second UPF (UPF2) is established for the second PDU session. That is, two separate paths are established for transmitting TSN traffic in the 5G network.

[0038] In a second embodiment (2), a 5G network includes a single user equipment (UE) and is configured to establish multiple redundant PDU sessions (PDU session 1, PDU session 2) connecting the UE and a base station gNB. A single UPF is established for both PDU sessions. The two PDU sessions are established via two different data network names, thus providing two separate paths for transmitting TSN traffic in the 5G network. In a variation of this embodiment, three or more redundant PDU sessions may be established by the 5G network.

[0039] In a third embodiment (3), the 5G network comprises a single user equipment (UE) and is configured to establish a single PDU session connecting the UE and a base station gNB. A single UPF is established for the PDU session. In this embodiment, separate paths for transmitting TSN traffic in the 5G network can be provided by dual connectivity techniques, i.e., by establishing multiple N3 interfaces between the user plane function UPF and multiple base stations gNBs, and / or by establishing separate paths between the RAN and the UE.

[0040] Each of the embodiments (1) to (3) can be implemented in an integration network as shown in FIG. 4 or FIG.

[0041] 8 illustrates a method according to a first embodiment. The CNC of the converged network sends system-level schedule information of the 5G network to an application function (AF) of the 5G network. The AF then informs a policy control function (PCF) of the 5G network of a redundancy policy of the 5G network. The system-level schedule information informs the 5G network of a time window in which TSN traffic is expected to arrive at the 5G network. The redundancy policy indicates the type of TSN traffic handling mechanism supported by the 5G network, which comprises a protocol for duplicating frames of the TSN traffic and a protocol for removing redundant copies of frames of the TSN traffic.

[0042] The 5G network comprises a number of UEs that process TSN traffic. These UEs may be identified through an International Mobile Subscriber Identity (IMSI) or any other unique identifier. In response to the AF informing the PCF of the redundancy policy, the first UE sends a first PDU session establishment request to an Access and Mobility Management Function (AMF) of the 5G network. The first PDU session establishment request may be triggered by the first UE or by the 5G network. In response, the AMF selects a Session Management Function (SMF) for the first PDU session, and the core network of the 5G network performs authentication (authorization) of the first PDU session. In response to the authentication of the first session of the PDU, the selected SMF selects a first User Plane Function (UPF) for the authenticated first PDU session.

[0043] The second UE then sends a second PDU session establishment request to an Access and Mobility Management Function (AMF) of the 5G network. The second PDU session establishment request is triggered by the 5G network. In response, the AMF selects a Session Management Function (SMF) for the second PDU session, and the core network of the 5G network performs authentication (authorization) of the second PDU session. In response to the authentication of the second PDU session, the selected SMF selects a second user plane function UPF, which is different from the first user plane function UPF, for the authenticated second PDU session. In this way, two PDU sessions with different endpoints (first UE and first UPF, second UE and second UPF) are established in the 5G network to handle TSN traffic, thus providing two separate paths for transmitting TSN traffic through the 5G network. In the embodiment of Figure 8, duplication of frames of TSN traffic and / or elimination of redundant copies of frames of TSN traffic are performed at the IP layer of the data network (DN). The transmission of TSN traffic over a 5G network is further described with reference to Figure 9.

[0044] FIG. 9 illustrates an exemplary implementation of the method of FIG. 8. The 5G network is connected to the TSN system through a virtual TSN bridge. The TSN traffic comprising a plurality of data frames may enter the 5G network from the UE side or from the network side. The frames of the TSN traffic received by the 5G network are replicated by the data network DN (e.g., by the IP layer of the data network or by the layer 2 of the data network where the PDU session is an Ethernet PDU session) according to the redundancy policy of the 5G network. For example, k copies of each frame are generated, where k is the number of multiple separate paths for transmitting the TSN traffic in the 5G network. Each of the k copies is then transmitted to the destination via a respective one of the multiple separate paths. At the destination, e.g., a node of the TSN system, it is determined whether one or more of the copies of the received frame are redundant based on the redundancy policy of the 5G network, and the copies determined to be redundant are erased by the TSN node. (For example, the received copies may be erased to leave only a single copy of each frame.)

[0045] Alternatively, a frame of the TSN traffic transmitted through the 5G network may be replicated by a node of the TSN network based on a redundancy policy of the 5G network before being transmitted through the k separate paths of the 5G network. At the destination, e.g., a node of the data network, it is determined whether one or more of the copies of the received frame are redundant based on the redundancy policy of the 5G network, and the copies determined to be redundant are erased by the data network. In a variation of this embodiment, both the erasure and the replication steps may be performed by the data network (DN) (e.g., by the IP layer / layer 2 of the data network).

[0046] The method according to the first embodiment may be implemented in the integration network shown in FIG. 4 or FIG.

[0047] FIG. 10 illustrates a method according to a second embodiment.

[0048] The CNC of the integrated network sends system-level schedule information of the 5G network to an application function (AF) of the 5G network. In response to the AF informing the PCF of the redundancy policy, the UE sends a first PDU session establishment request to an access and mobility management function (AMF) of the 5G network. The first PDU session establishment request may be triggered by the UE or by the 5G network. The first PDU session is established via a first data network name (DNN). In response, the AMF selects a session management function (SMF) of the first PDU session, and the core network of the 5G network performs authentication (authorization) of the first PDU session. In response to the authentication of the first session of the PDU, the selected SMF selects a user plane function UPF for the authenticated first PDU session.

[0049] The UE then sends a second PDU session establishment request to an Access and Mobility Management Function (AMF) of the 5G network to establish a redundant PDU session with the same UE. The second PDU session establishment request is triggered by the 5G network. The second PDU session is established via a second data network name (DNN) different from the first data network name (DNN). In response, the AMF selects a session management function (SMF) for the second PDU session, and the core network of the 5G network performs authentication (authorization) of the second PDU session. In response to the authentication of the second PDU session, the selected SMF selects a user plane function UPF for the authenticated second PDU session. In this way, two PDU sessions with different data network names are established in the 5G network to handle TSN traffic, thus providing separate multiple paths for transmitting TSN traffic through the 5G network. In a variation of this embodiment, three or more redundant PDU sessions may be established by the 5G network to handle TSN traffic. In the embodiment of FIG. 10, duplication of frames of the TSN traffic and / or elimination of redundant copies of frames of the TSN traffic is performed at the IP layer of the data network DN.

[0050] The transmission of TSN traffic over a 5G network is further described with reference to FIG. 11.

[0051] The 5G network is connected to the TSN system via a virtual TSN bridge. TSN traffic comprising multiple data frames can enter the 5G network from the UE side or from the network side.

[0052] Frames of TSN traffic received by the 5G network are replicated by the 5G network (e.g., at the IP layer / Layer 2 of the Ethernet protocol stack, at the UPF, or at the UE) according to a redundancy policy of the 5G network. For example, k copies of each frame are generated, where k is the number of separate paths for transmitting TSN traffic in the 5G network. Each of the k copies is then transmitted to a destination via a respective one of the separate paths. At the destination, e.g., the IP layer / Layer 2 of the Ethernet protocol stack, the UPF, or the UE, it is determined whether one or more of the copies of the received frame are redundant based on the redundancy policy of the 5G network, and the received copies determined to be redundant are erased by the IP layer / Layer 2 of the Ethernet protocol stack, the UPF, or the UE. (For example, the received copies may be erased to leave only a single copy of each frame.)

[0053] The method of FIG. 10 may be implemented in the integration network shown in FIG. 4 or FIG.

[0054] 12 illustrates a method according to a third embodiment. The CNC of the converged network initiates a PDU establishment procedure by sending system-level schedule information of the 5G network to an application function (AF) of the 5G network. The AF then informs a policy control function (PCF) of the 5G network of a redundancy policy of the 5G network. The system-level schedule information informs the 5G network of a time window during which TSN traffic is expected to arrive at the 5G network. The redundancy policy indicates the type of TSN traffic handling mechanism supported by the 5G network, which comprises a protocol for duplicating frames of the TSN traffic and a protocol for removing redundant copies of frames of the TSN traffic.

[0055] In response to the AF informing the PCF of the redundancy policy, the UE sends a PDU session establishment request to an Access and Mobility Management Function (AMF) of the 5G network. The PDU session establishment request may be triggered by the UE or by the 5G network. In response, the AMF selects a Session Management Function (SMF) for the PDU session, and the core network of the 5G network performs authentication (authorization) of the PDU session. In response to the authentication of the first session of the PDU, the selected SMF selects a User Plane Function (UPF) for the authenticated PDU session.

[0056] Once the PDU session establishment procedure is complete, frame duplication and erasure may be handled via a number of different protocols. The transmission of TSN traffic over 5G networks is further described with reference to FIG.

[0057] According to the first protocol ("embodiment A"), frame / packet duplication and erasure is performed between the UPF and the RAN of the 5G network at the GPRS Tunneling Protocol (GTP) layer. The GTP layer duplicates received frames of TSN data according to the redundancy policy of the 5G network. For example, k copies of each frame are generated, where k is the number of separate paths for transmitting TSN traffic in the 5G network. Each of the k copies is then transmitted to a destination via a respective one of the separate paths. At the destination, e.g., the GTP layer, it is determined whether one or more of the copies of the received frame are redundant based on the redundancy policy of the 5G network, and the received copies determined to be redundant are erased by the GTP layer. (For example, the received copies may be erased to leave only a single copy of each frame.)

[0058] The UPF establishes two different N3 interfaces (tunnels) to transmit the TSN traffic. On the RAN side, the two N3 interfaces enable separate endpoints by means of a dual connectivity technique where two different base station gNBs are used, namely a master gNB (MgNB) and a secondary gNB (SgNB). Thus, two separate multiple paths are provided for transmitting the TSN traffic through the 5G network. The two base stations gNBs are connected via an Xn interface.

[0059] According to a second protocol ("embodiment B"), the duplication and elimination of frames / packets takes place between the UE and the RAN at different layers of the air interface. For example, as shown in Figure 14, duplication and elimination takes place at the Service Data Adaptation Protocol (SDAP) layer, which handles the mapping of QoS flows to data radio bearers. The SDAP layer duplicates the SDAP PDUs and adds another PDCP entity so that the original and duplicated PDUs are sent over two different Data Radio Bearers (DRBs).

[0060] Alternatively, as shown in Figure 15, frame duplication and erasure may occur at the Packet Data Convergence Protocol (PDCP) layer of the 5G network. The PDCP layer duplicates the PDCP PDU. The PDCP layer adds another Radio Link Control (RLC) entity and performs a bearer splitting operation such that the original and duplicated PDUs are transmitted over two separate paths, one via the master gNB MgNB and the other via the secondary gNB SgNB.

[0061] In an embodiment, both the first protocol and the second protocol may be implemented.

[0062] The method of FIG. 12 may be implemented in the integration network shown in FIG. 4 or FIG.

[0063] The above-mentioned duplication and elimination techniques may be combined in one embodiment. For example, while the duplication / elimination techniques are implemented within a single PDU session, multiple PDU sessions may be used, thereby providing additional isolated paths for data transmission and improving the reliability of data transmission within the network.

[0064] In a variation of the above embodiment, a FRER-compliant TSN node transmitting traffic towards a 5G network dynamically flushes duplicate frames received from multiple paths (i.e., frames duplicated by the FRER protocol of the TSN system) based on the level of redundant paths available in the 5G network. A TSN node transmitting traffic towards a 5G network may admit (forward) duplicate frames received from "k" paths with probability 1 / Θ, where Θ is the average number of paths available in the 5G network for TSN traffic. The average number of paths in the 5G network may be calculated as follows: [Paths_UE-RAN+Paths_RAN-Core] / 2 Here, Paths_UE-RAN indicates the total number of paths available for redundant traffic between the UE and the RAN of the 5G network, and Paths_RAN-Core indicates the total number of paths available for redundant traffic between the RAN and the core network of the 5G network. For example, for two independent PDU sessions (with either a single UE or multiple UEs), the average number of paths is 2, for a single PDU session with duplication / erasure in the air interface or N3 interface, the average number of paths is 1.5, and if multipath transmission is not supported by the 5G network, the average number of paths is 1.

[0065] In a variation of the above embodiment, a TSN node receiving traffic from a 5G network replicates received frames (over the “k” available paths) with probability 1 / Θ, where Θ is the average number of paths available in the 5G system for TSN traffic.

[0066] Information regarding the average number of paths in the 5G network may be shared with TSN nodes via the CNC.

[0067] Although specific embodiments have been described, these embodiments are presented as examples only and are not intended to limit the scope of the present invention. Indeed, the novel devices and methods described herein may be embodied in other various forms, and further, various omissions, substitutions, and changes in the form of the devices, methods, and products described herein may be made without departing from the spirit of the present invention. The appended claims and their equivalents are intended to cover such forms or modifications as fall within the scope and spirit of the present invention.

Claims

1. 1. A method for transmitting data between a time sensitive networking (TSN) system and a 5G network, the method comprising: receiving data comprising a plurality of frames from the time sensitive networking (TSN) system; defining k disjoint paths for transmitting the data across the 5G network, where k≧2; performing, by the 5G network, at least one of a process (a) and a process (b) for each frame of the data; wherein: (a) transmitting k copies of each of the frames to a destination via respective ones of a plurality of separate paths; determining whether one or more of the k transmitted copies received at the destination are redundant based on a redundancy policy of the 5G network indicating a protocol for eliminating redundant copies of frames of TSN traffic; and eliminating the copies determined to be redundant. (b) generating k copies of each of the frames based on a redundancy policy of the 5G network indicating a protocol for replicating multiple frames of TSN traffic; and transmitting the multiple copies of each of the frames to a destination via respective ones of the separated multiple paths.

2. 2. The method of claim 1, wherein the 5G network comprises a first user equipment (UE) and a data network (DN), and defining the k disjoint multiple paths comprises establishing a connection between the first user equipment (UE) and the data network (DN).

3. 3. The method of claim 2, wherein establishing the connection comprises establishing at least one protocol data unit (PDU) session for the first user equipment (UE).

4. 4. The method of claim 3, wherein the 5G network further comprises a second user equipment (UE), and wherein establishing the connection comprises establishing a first protocol data unit (PDU) session with the first user equipment (UE) and establishing a second protocol data unit (PDU) session with the second user equipment (UE).

5. 5. The method of claim 4, wherein establishing the first protocol data unit (PDU) session comprises selecting a first user plane function (UPF) for the first protocol data unit (PDU) session, and establishing the second protocol data unit (PDU) session comprises selecting a second user plane function (UPF) for the second protocol data unit (PDU) session.

6. 5. The method of claim 4, wherein at least one of (i) eliminating the multiple copies determined to be redundant and (ii) generating k copies of each frame based on a redundancy policy of the 5G network indicating a protocol for duplicating multiple frames of TSN traffic is performed by the data network (DN) of the 5G network.

7. 4. The method of claim 3, wherein establishing the connection comprises establishing a first protocol data unit (PDU) session with the first user equipment (UE) and establishing a second protocol data unit (PDU) session with the first user equipment (UE).

8. 8. The method of claim 7, wherein the first protocol data unit (PDU) session is established via a first data network name (DNN) of the 5G network and the second protocol data unit (PDU) session is established via a second data network name (DNN) of the 5G network.

9. 8. The method of claim 7, wherein at least one of (i) eliminating the multiple copies determined to be redundant and (ii) generating the k copies of each frame based on a redundancy policy of the 5G network indicating a protocol for duplicating multiple frames of TSN traffic is performed by an IP layer of the 5G network, by a User Plane Function (UPF) of the 5G network, or by the first user equipment (UE).

10. 4. The method of claim 3, wherein establishing the connection comprises establishing, by a User Plane Function (UPF) of the 5G network, a first N3 tunnel and a second N3 tunnel for transmitting the data across the 5G network.

11. The method according to claim 10, wherein the first N3 tunnel connects the user plane function (UPF) and a master base station (MgNB), and the second N3 tunnel connects the user plane function (UPF) and a secondary base station (SgNB).

12. 11. The method of claim 10, wherein at least one of (i) eliminating the multiple copies determined to be redundant and (ii) generating the k copies of each frame based on a redundancy policy of the 5G network indicating a protocol for duplicating multiple frames of TSN traffic is performed by a GPRS Tunneling Protocol (GTP) layer of the 5G network.

13. 11. The method of claim 10, wherein at least one of (i) eliminating the multiple copies determined to be redundant and (ii) generating the k copies of each frame based on a redundancy policy of the 5G network indicating a protocol for replicating multiple frames of TSN traffic is performed by a layer of an air interface protocol stack of the 5G network.

14. 14. The method of claim 13, wherein (i) eliminating copies determined to be redundant and (ii) generating the k copies of each frame based on a redundancy policy of the 5G network indicating a protocol for duplicating multiple frames of TSN traffic are performed by a Service Data Adaptation Protocol (SDAP) layer of the 5G network.

15. 14. The method of claim 13, wherein (i) eliminating copies determined to be redundant and (ii) generating the k copies of each frame based on a redundancy policy of the 5G network indicating a protocol for duplicating multiple frames of TSN traffic is performed by a Packet Data Convergence Protocol (PDCP) layer of the 5G network.

16. 1. A method for transmitting data comprising a plurality of frames between a time sensitive networking (TSN) system and a 5G network, the method comprising: performing, for each frame of data, by the time sensitive networking (TSN) system, one of operations (c) and (d). wherein: and (c) obtaining k copies of each of the frames based on a redundancy policy of the 5G network indicating a protocol for duplicating multiple frames of TSN traffic and a protocol for eliminating multiple redundant copies of the multiple frames of TSN traffic, and transmitting the copies to a layer of the 5G network configured to eliminate multiple redundant copies of each of the frames based on the redundancy policy. (d) receiving k copies of each frame from the 5G network, determining whether one or more of the received copies are redundant based on a redundancy policy of the 5G network indicating a protocol for removing redundant copies of frames of TSN traffic, and erasing the copies determined to be redundant.

17. 17. The method of claim 16, wherein transmitting the multiple copies comprises passing the received multiple copies with probability 1 / Θ, where Θ is an average number of multiple paths available in the 5G network for TSN traffic.

18. 17. The method of claim 16, wherein obtaining the k copies of each frame comprises duplicating a plurality of received frames of data with probability 1 / Θ, where Θ is an average number of paths available in the 5G network for TSN traffic.

19. 13. One or more non-transitory storage media comprising a plurality of computer instructions executable by a processor, the plurality of computer instructions, when executed by the processor, causing the processor to perform the method of claim 1.

20. 17. One or more non-transitory storage media comprising a plurality of computer instructions executable by a processor, the plurality of computer instructions, when executed by the processor, causing the processor to perform the method of claim 16.

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