US-12621074-B2 - Technique for transporting a time protocol message for time-sensitive networking

Abstract

A technique of transporting a time protocol message for time-sensitive networking, TSN, from a first station ( 910 ) to a second station ( 920 ) through a wireless network ( 900 ) including at least one radio device wirelessly connected to at least one base station ( 400 ) of the wireless network ( 900 ) is provided. As to a method aspect, a method performed by at least one or each of the at least one radio device comprises a step of transmitting to the wireless network ( 900 ) a radio device request message requesting establishment of a packet data unit, PDU, session between the radio device and the wireless network ( 900 ), the radio device request message being indicative of a time protocol of the time protocol message. The method further comprises at least one of the steps of receiving from and transmitting to the at least one base station ( 400 ) of the wireless network ( 900 ) the time protocol message according to a Quality of Service, QoS, flow for transporting the time protocol message in the wireless network ( 900 ). The QoS flow is unambiguously or uniquely associated with at least one of the PDU session and the time protocol.

Inventors

• John Walter Diachina
• Kun Wang
• Paul Schliwa-Bertling
• Dhruvin Patel

Assignees

• TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)

Dates

Publication Date

20260505

Application Date

20210610

Claims (20)

1. 1 . A method of transporting a time protocol message for Time-Sensitive Networking (TSN) from a first station to a second station through a wireless network including at least one radio device wirelessly connected to at least one base station of the wireless network, the method performed by at least one radio device and comprising: determining that the at least one radio device or the wireless network is arranged as a TSN bridge between the first station and the second station; transmitting to the wireless network a radio device request message requesting establishment of a Packet Data Unit (PDU) session between the radio device and the wireless network, the radio device request message being indicative of a time protocol of the time protocol message, wherein the radio device request message is transmitted responsive to the determination; and receiving from or transmitting to the at least one base station of the wireless network the time protocol message according to a Quality of Service (QOS) flow for transporting the time protocol message in the wireless network, wherein the QoS flow is uniquely associated with at least one of the PDU session and the time protocol.
2. 2 . The method of claim 1 , wherein the indication of the time protocol triggers the wireless network to include an ingress timestamp in the time protocol message upon ingress of the time protocol message at the wireless network.
3. 3 . The method of claim 1 , wherein the indication of the time protocol triggers the wireless network to perform one or more of including an egress timestamp, performing an egress timestamp, and modifying the time protocol message to indicate the difference between the ingress and egress timestamps upon egress of the time protocol message at the wireless network.
4. 4 . The method of claim 1 , the method further comprising or initiating the steps: receiving, from the first station, the time protocol message; and transmitting, to the wireless network, the time protocol message including an ingress timestamp according to the time protocol in the PDU session.
5. 5 . The method of claim 1 , the method further comprising: receiving, from the wireless network, the time protocol message in the PDU session; and sending, to the second station, the time protocol message including an egress timestamp or an indication of the difference between the ingress timestamp and the egress timestamp according to the time protocol.
6. 6 . The method of claim 1 , wherein the radio device request message comprises a flag that is indicative of the time protocol of the time protocol message.
7. 7 . The method of claim 1 , wherein the determination comprises determining that the at least one radio device supports connectivity with at least one Device-Side TSN Translator (DS-TT).
8. 8 . The method of claim 7 , wherein the time protocol message is received from the first station using an ingress DS-TT; or wherein the time protocol message is sent to the second station using an egress DS-TT; wherein the ingress DS-TT is connected or connectable to the first station; or wherein the egress DS-TT is connected or connectable to the second station.
9. 9 . A method of transporting a time protocol message for Time-Sensitive Networking (TSN) from a first station to a second station through a wireless network including at least one radio device wirelessly connected to a base station of the wireless network, the method performed by a Core Network (CN) of the wireless network and comprising: receiving, from the at least one radio device, a radio device request message requesting establishment of a Packet Data Unit (PDU) session between the radio device and the wireless network, the radio device request message being indicative of a time protocol of the time protocol message, wherein the radio device request message is received responsive to determining, by the at least one radio device, that the at least one radio device or the wireless network is arranged as a TSN bridge between the first station and the second station; and responsive to the indication of the time protocol in the radio device request message, sending, to the base station of the wireless network, a CN request message requesting the establishment of the PDU session between the at least one radio device and the wireless network, the CN request message being indicative of a Quality of Service (QOS) flow for transporting the time protocol message in the wireless network.
10. 10 . The method of claim 9 , wherein the wireless network comprises at least one Network-Side TSN Translator (NW-TT) connected to a User Plane Function (UPF) of the wireless network, and wherein the indication of the time protocol and/or the indication of the QoS flow triggers the UPF or the NW-TT to include in the time protocol message at least one of: an ingress timestamp, an egress timestamp, and a difference between the ingress and egress timestamps.
11. 11 . The method of claim 9 , wherein the wireless network comprises at least one Device-Side TSN Translator (DS-TT) connected to the at least one radio device of the wireless network, and wherein the indication of the time protocol or the indication of the QoS flow triggers the radio device or the DS-TT to include in the time protocol message least one of: an ingress timestamp, an egress timestamp, and a difference between the ingress and egress timestamps.
12. 12 . The method of claim 9 , wherein the QoS flow is used exclusively for transporting messages according to the time protocol.
13. 13 . The method of claim 9 , wherein at least one of the PDU session and the QoS flow is indicated by means of a QoS Flow Identifier (QFI) or a QoS indicator.
14. 14 . The method of claim 13 , wherein a predefined or configured table comprises an entry for the QoS flow used for the transporting of the time protocol message in the wireless network, optionally the QFI or QoS indicator being an index of the table.
15. 15 . The method of claim 9 , wherein the core network comprises an Access and Mobility management Function (AMF) and a Session Management Function (SMF), the method being performed by the SMF, wherein the SMF triggers the AMF to send the CN request message to the base station.
16. 16 . A method of transporting a time protocol message for Time-Sensitive Networking (TSN) from a first station to a second station through a wireless network including at least one radio device wirelessly connected to the wireless network, the method performed by a User Plane Function (UPF) of the wireless network and comprising: storing a criterion for a Packet Data Unit (PDU) comprising a time protocol message from the first station, wherein a radio device request message indicative of the time protocol of the time protocol message is received by a Core Network (CN) responsive to determining, by the at least one radio device, that the at least one radio device or the wireless network is arranged as a TSN bridge between the first station and the second station; and relaying a PDU to the at least one radio device connected to the second station, if the PDU fulfills the criterion.
17. 17 . The method of claim 16 , wherein the step of storing the criterion comprises: receiving, from a CN of the wireless network, a CN control message that is indicative of the criterion for the PDU comprising the time protocol message according to the time protocol of the TSN.
18. 18 . The method of claim 17 , wherein the criterion comprises at least one of: a link layer criterion for at least one link layer field in the PDU; a Medium Access Control (MAC) address in the PDU; and an Ethertype field value in the PDU.
19. 19 . The method of claim 17 , wherein the wireless network comprises an ingress Network-Side TSN Translator (NW-TT) connected to the UPF, the method further comprising or initiating the steps performed by the UPF: forwarding the criterion to the ingress NW-TT; and receiving the PDU fulfilling the criterion from the ingress NW-TT.
20. 20 . The method of claim 17 , wherein fulfilment of the criterion triggers at least one of an ingress Network-Side TSN Translator (NW-TT) and the UPF to include an ingress timestamp in the time protocol message upon ingress of the time protocol message at the wireless network.

Description

TECHNICAL FIELD The present disclosure relates to a technique for transporting a time protocol message for time-sensitive networking. More specifically, and without limitation, methods and devices are provided for transporting a time protocol message for time-sensitive networking from a first station to a second station through a wireless network including at least one radio device wirelessly connected to the wireless network. BACKGROUND Packet-switched networks per se, especially without a centralized scheduler such as Ethernet, have no constraints on end-to-end delay or synchronization precision. The Time-Sensitive Networking (TSN) task group of the IEEE 802.1 working group defines extensions for Ethernet to control the time of transport of messages. Fifth Generation New Radio (5G NR) according to the Third Generation Partnership Project (3GPP) is to support TSN. That is, a Fifth Generation System (5G System or 5GS) can be integrated as a time-aware system or TSN bridge within a TSN network, e.g. an Ethernet-based TSN network. Use cases for such a system include factory automation networking or any synchronized coordination. While an existing 5GS can be connected with a TSN network through a TSN translator, the existing 5GS serves a diversity of applications which do not provide essential functions for TSN such as distributing a grandmaster clock to TSN end stations. SUMMARY Accordingly, there is a need for technique that allows establishing a time base throughout a system that comprises a wireless network. Alternatively or more specifically, there is a need for a technique that allows distributing a clock for TSN in a system comprising a wireless network. According to first aspect, a method of transporting a time protocol message for time-sensitive networking (TSN) from a first station to a second station through a wireless network including at least one radio device wirelessly connected to at least one base station of the wireless network is provided. The method may be performed by at least one or each of the at least one radio device. The method comprises or initiates a step of transmitting to the wireless network a radio device request message requesting establishment of a packet data unit (PDU) session between the radio device and the wireless network. The radio device request message is indicative of a time protocol of the time protocol message. The method may further comprise or initiate a step of receiving from and/or transmitting to the at least one base station of the wireless network the time protocol message according to a Quality of Service (QoS) flow for transporting the time protocol message in the wireless network. The QoS flow may be unambiguously or uniquely associated with the PDU session and/or with the time protocol. Embodiments of the technique can, based on (e.g., responsive to) the indication of the time protocol in the radio device request message, allocate resources of the wireless network and/or trigger processes in the wireless network. The allocated resources may have an upper limit on a delay of the transport. Alternatively or in addition, the triggered processes may include timestamps in the time protocol message (e.g., at ingress and/or egress to the wireless network) and/or may evaluate and/or correct in timestamps the time protocol message. For example, the wireless network can, based on the time protocol indicated in the radio device request message, allocate resources specifically for the time protocol message and/or trigger processes specifically for the time protocol message by allocating a specific PDU session in response to the radio device request. The specific PDU session may be associated with a specific Quality of Service flow. Based on the specific PDU session and/or the specific Quality of Service flow, components (e.g., nodes or entities) of the wireless network may be triggered to perform the processes specifically for the time protocol message. For example, the wireless network can, based on the time protocol indicated in the radio device request message, distribute a clock from the first station to the second station through the wireless network by means of the time protocol message. The first method aspect may be performed by the radio device (e.g., a UE) operating within the context of the wireless network (e.g., a 5GS) serving as a time-aware bridge and/or supporting the first and second stations (e.g., end stations) requiring the use of one or more TSN grandmaster (GM) clocks. Embodiments of the technique can ensure support for distribution of these TSN GM clocks using 5GS signaling resources. The technique can be implemented for or applied to any one of at least two basic use cases. In a first use case, the first station (e.g., a TSN GM clock source) is located at an end station reachable through a network-side TSN translator (NW-TT). In a second use case, the first station (e.g., a TSN GM clock source) is located at an end station reachable through a