Patent Description:
In regard to time synchronization in Fifth Generation (<NUM>) to support Time Sensitive Networking (TSN), Third Generation Partnership Project (3GPP) Release <NUM> work is ongoing and different options are being discussed to address the needs for time synchronization as required by TSN and industrial applications. The support of multiple time domains in <NUM> is especially an open topic.

In 3GPP Technical Report (TR) <NUM>, Solution#<NUM> Option <NUM> provides a solution to support TSN synchronization. The solution is further merged with Solution #<NUM> of TR 3GPP <NUM> [<NUM>].

<FIG> illustrates an example procedure of supporting multiple TSN domains using a "<NUM> time-aware system", as described in TR <NUM> [<NUM>].

Patent Cooperation Treat (PCT) application <CIT>, published as <CIT> and is referred to herein as Prior Application #<NUM>, addressed the delivery of synchronization messages (g)PTP using <NUM> Radio Access Network (RAN) signaling (System Information Block (SIB) / Radio Resource Control (RRC) signaling).

PCT application <CIT>, published as <CIT> and is referred to herein as Prior Application #<NUM>, addressed conveying synchronization messages (g)PTP using a user plane PDU session. This prior provisional patent application proposed methods for filtering different "domainNumbers" from gPTP messages so that transmission of the (g)PTP can be specifically according to only the "domain" desired by the UE.

Document <NPL>, discloses delivering timing information from a TSN working domain via UEs to respective end stations. The end station can then select proper TSN timing information.

The invention is defined by the independent claims <NUM>, <NUM>, <NUM>, <NUM> and <NUM>. According to the present disclosure, methods, a node and a network node according to the independent claims are provided. Developments are set forth in the dependent claims. Systems and methods related to conveying Time Sensitive Networking (TSN) synchronization information within a cellular communication system (e.g., a Fifth Generation System (5GS)) are disclosed. In one embodiment, a method performed by a User Equipment (UE) in a cellular communications system or a TSN Translator (TT) associated with the UE comprises receiving, from a TSN end station, a Precision Time Protocol (PTP) or generalized PTP (gPTP) announce message comprising information that identifies one or more clock domains for which the TSN end station desires to receive PTP or gPTP messages. The method further comprises sending, to a core network node in the cellular communications system, either: (a) the information that identifies the one or more clock domains extracted from the PTP or gPTP announce message or (b) the PTP or gPTP announce message. Using this information, UE specific PTP or gPTP message filtering may be applied to thereby ensure clock domain information from the TSN network within the context of PTP or gPTP messages is only relayed to any given UE/TT if that UE/TT supports a TSN end station that has an interest in the corresponding clock domain. This can result is substantial savings in the amount of radio interface bandwidth used in support of transmitting PTP or gPTP messages to UEs.

According to the invention, the information that identifies a plurality of clock domains comprises one or more wanted domain numbers that identify the plurality clock domains for which the TSN end station desires to receive PTP or gPTP messages.

In one embodiment, sending either (a) or (b) comprises sending either (a) or (b) via either control plane signaling or a user plane message(s).

In one embodiment, the method further comprises extracting the information that identifies the one or more clock domains from the PTP or gPTP announce message. The step of sending either (a) or (b) comprises sending the information that identifies the one or more clock domains extracted from the PTP or gPTP message. In one embodiment, the UE or TT terminates the PTP or gPTP announce message. In one embodiment, sending the information that identifies the one or more clock domains extracted from the PTP or gPTP message comprises sending the information that identifies the one or more clock domains extracted from the PTP or gPTP message via control plane signaling in a new information element. In another embodiment, sending the information that identifies the one or more clock domains extracted from the PTP or gPTP message comprises sending the information that identifies the one or more clock domains extracted from the PTP or gPTP message in a payload of a user plane message. In another embodiment, sending the information that identifies the one or more clock domains extracted from the PTP or gPTP message comprises sending the information that identifies the one or more clock domains extracted from the PTP or gPTP message in a header of a user plane message.

In one embodiment, sending either (a) or (b) comprises sending the PTP or gPTP announce message via control plane signaling.

In one embodiment, sending either (a) or (b) comprises encapsulating the PTP or gPTP announce message into a user plane Protocol Data Unit (PDU) payload of a user plane message and sending the user plane message.

Corresponding embodiments of a node for a cellular communications system that operates as a virtual TSN bridge node being either a UE or a TT at the UE are also disclosed. In one embodiment, the node is adapted to receive, from a TSN end station, a PTP or gPTP announce message comprising information that identifies one or more clock domains for which the TSN end station desires to receive PTP or gPTP messages. The node is further adapted to send, to a core network node in the cellular communications system, either: (a) the information that identifies the one or more clock domains extracted from the PTP or gPTP announce message or (b) the PTP or gPTP announce message.

In one embodiment, a node for a cellular communications system that operates as a virtual TSN bridge node being either a UE or a TT at the UE is provided, where the node comprises processing circuitry adapted to cause the node to receive, from a TSN end station, a PTP or gPTP announce message comprising information that identifies one or more clock domains for which the TSN end station desires to receive PTP or gPTP messages. The processing circuitry is further adapted to cause the node to send, to a core network node in the cellular communications system, either: (a) the information that identifies the one or more clock domains extracted from the PTP or gPTP announce message or (b) the PTP or gPTP announce message.

Embodiments of a method performed by a network node of a cellular communications system that operates to provide support for one or more virtual TSN nodes are also provided. In one embodiment, the method comprises obtaining information that identifies one or more clock domains for which a TSN end station desires to receive PTP or gPTP messages via a UE or TT associated with the UE. The method further comprises performing one or more actions using the obtained information.

In one embodiment, performing the one or more actions comprises providing the information to another network node.

In one embodiment, performing the one or more actions comprises performing clock domain filtering of incoming PTP or gPTP messages from the TSN network such that only PTP or gPGP messages of the one or more clock domains desired by a TSN end station are delivered to the UE or TT associated with the TSN end station.

In one embodiment, the network node is a Session Management Function (SMF) or a Policy Control Function (PCF), and performing the one or more actions comprises modifying a corresponding Protocol Data Unit (PDU) session such that a corresponding User Plane Function (UPF) only routes PTP or gPTP messages of the one or more clock domains to the UE or TT associated with the TSN end station.

In one embodiment, the network node is a SMF or PCF, and performing the one or more actions comprises sending the information to a corresponding UPF.

In one embodiment, the network node is a SMF, and performing the one or more actions comprises instructing a corresponding UPF to forward PTP or gPTP messages to a corresponding base station using a dedicated tunnel between the base station and the UPF. In one embodiment, the PTP or gPTP messages that the corresponding base station is to support comprises PTP or gPTP messages of the one or more clock domains.

In one embodiment, the network node is a base station, and performing the one or more actions comprises performing clock domain filtering of PTP or gPTP messages at the base station.

In one embodiment, the network node is a UPF, and performing the one or more actions comprises performing clock domain filtering of PTP or gPTP messages at the UPF.

In one embodiment, the network node is a UPF, and performing the one or more actions comprises sending the information to another network node.

In one embodiment, obtaining the information comprises obtaining the information from a Centralized Network Configuration (CNC) of an associated TSN network via an Application Function (AF).

In one embodiment, obtaining the information comprises receiving either: a control plane signaling message comprising the information or a user plane message comprising the information.

In one embodiment, obtaining the information comprises receiving a control plane signaling message comprising a PTP or gPTP announce message, wherein the PTP or gPTP announce message comprises the information that identifies the one or more clock domains for which the TSN end station desires to receive PTP or gPTP messages.

In one embodiment, obtaining the information comprises receiving a user plane message comprising the information in a payload of the user plane message.

In one embodiment, obtaining the information comprises receiving a user plane message comprising the information in a header of the user plane message.

Corresponding embodiments of a network node are also disclosed. In one embodiment, a network node of a cellular communications system that operates to provide support for one or more virtual TSN nodes is provided, wherein the network node is adapted to obtain information that identifies one or more clock domains for which a TSN end station desires to receive PTP or gPTP messages via a UE or TT associated with the UE and perform one or more actions using the obtained information.

In one embodiment, a network node of a cellular communications system that operates to provide support for one or more virtual TSN nodes is provided, wherein the network node comprises processing circuitry configured to cause the network node to obtain information that identifies one or more clock domains for which a TSN end station desires to receive PTP or gPTP messages via a UE or TT associated with the UE and perform one or more actions using the obtained information.

Radio Access Node: As used herein, a "radio access node" or "radio network node" is any node in a Radio Access Network (RAN) of a cellular communications network that operates to wirelessly transmit and/or receive signals. Some examples of a radio access node include, but are not limited to, a base station (e.g., a New Radio (NR) base station (gNB) in a Third Generation Partnership Project (3GPP) Fifth Generation (<NUM>) NR network or an enhanced or evolved Node B (eNB) in a 3GPP Long Term Evolution (LTE) network), a high-power or macro base station, a lowpower base station (e.g., a micro base station, a pico base station, a home eNB, or the like), and a relay node.

Core Network Node: As used herein, a "core network node" is any type of node in a core network or any node that implements a core network function. Some examples of a core network node include, e.g., a Mobility Management Entity (MME), a Packet Data Network Gateway (P-GW), a Service Capability Exposure Function (SCEF), a Home Subscriber Server (HSS), or the like. Some other examples of a core network node include a node implementing a Access and Mobility Function (AMF), a User Plane Function (UPF), a Session Management Function (SMF), an Authentication Server Function (AUSF), a Network Slice Selection Function (NSSF), a Network Exposure Function (NEF), a Network Repository Function (NRF), a Policy Control Function (PCF), a Unified Data Management (UDM), or the like.

Some examples of a wireless device include, but are not limited to, a User Equipment (UE) in a 3GPP network and a Machine Type Communication (MTC) device.

There currently exist certain challenge(s) related to time synchronization in <NUM> to support Time Sensitive Networking (TSN). Depending upon how Precision Time Protocol (PTP) or generalized Precision Time Protocol (gPTP) frames or messages are transported in the <NUM> system (5GS) and especially what transmission type (broadcast, multicast, unicast) is chosen at the RAN, RAN knowledge about what time or clock domain is needed by each UE may be very important, but is not supported today. For multicast and unicast based transmission methods in particular, the volume of TSN time domain related information sent over the radio interface could be significantly reduced if the RAN was provided with this knowledge.

The following problems are addressed herein:.

Certain aspects of the present disclosure and their embodiments may provide solutions to the aforementioned or other challenges. In some embodiments, a method is described that is not limited to only conveying UE or end station specific "domainNumber" information.

Certain embodiments may provide one or more of the following technical advantage(s). For example, in some embodiments, UE specific gPTP message filtering may be applied at the UPF to thereby ensure clock domain information received by the UPF/TSN Translator (TT) (from the TSN network) within the context of gPTP messages is only relayed to any given UE if it has an interest in the corresponding clock domain indicated by the DomainNumber field of gPTP messages. This can result in a substantial savings in the amount of radio interface bandwidth used in support of transmitting gPTP messages to UEs.

As another example, in some embodiments, gPTP message filtering may be applied at the gNB to thereby ensure clock domain information received by the gNB from the UPF/TT within the context of gPTP messages is only relayed over the radio interface if there is at least one UE that has an interest in the corresponding clock domain indicated by the DomainNumber field of gPTP messages. This can result in a substantial savings in the amount of radio interface bandwidth used in support of transmitting gPTP messages to UEs.

As another example, supporting a mobility case, embodiments of the present disclosure allow a mobile UE or mobile end station to freely move among different cells. Embodiments described herein dynamically support the efficient redistribution of domain numbers to the UE / mobile end station regardless of the UE / mobile end station location.

As another example, embodiments of the present disclosure support the mobility case, where UE or mobile end station needs to merge time domains. An application may need an end station to change domain numbers (e.g., merged working domain case described in 3GPP Technical Specification (TS) <NUM>). Embodiments of the present disclosure allow a UE / end station to dynamically get a corresponding domain number that an application may need in an efficient manner.

Embodiments described herein relate to using the 5GS as a virtual TSN node(s). Thus, before describing embodiments of the present disclosure in more detail, a brief discussion of a 5GS is beneficial. In this regard, <FIG> illustrates one example of a cellular communications network <NUM> according to some embodiments of the present disclosure. In the embodiments described herein, the cellular communications network <NUM> is a <NUM> NR network. In this example, the cellular communications network <NUM> includes base stations <NUM>-<NUM> and <NUM>-<NUM>, which in <NUM> NR are referred to as gNBs, controlling corresponding macro cells <NUM>-<NUM> and <NUM>-<NUM>. The base stations <NUM>-<NUM> and <NUM>-<NUM> are generally referred to herein collectively as base stations <NUM> and individually as base station <NUM>. Likewise, the macro cells <NUM>-<NUM> and <NUM>-<NUM> are generally referred to herein collectively as macro cells <NUM> and individually as macro cell <NUM>. The cellular communications network <NUM> may also include a number of low power nodes <NUM>-<NUM> through <NUM>-<NUM> controlling corresponding small cells <NUM>-<NUM> through <NUM>-<NUM>. The low power nodes <NUM>-<NUM> through <NUM>-<NUM> can be small base stations (such as pico or femto base stations) or Remote Radio Heads (RRHs), or the like. Notably, while not illustrated, one or more of the small cells <NUM>-<NUM> through <NUM>-<NUM> may alternatively be provided by the base stations <NUM>. The low power nodes <NUM>-<NUM> through <NUM>-<NUM> are generally referred to herein collectively as low power nodes <NUM> and individually as low power node <NUM>. Likewise, the small cells <NUM>-<NUM> through <NUM>-<NUM> are generally referred to herein collectively as small cells <NUM> and individually as small cell <NUM>. The base stations <NUM> (and optionally the low power nodes <NUM>) are connected to a core network <NUM>.

<FIG> illustrates a wireless communication system represented as a <NUM> network architecture composed of core Network Functions (NFs), where interaction between any two NFs is represented by a point-to-point reference point/interface. <FIG> can be viewed as one particular implementation of the system <NUM> of <FIG>.

Seen from the access side the <NUM> network architecture shown in <FIG> comprises a plurality of UEs <NUM> connected to either a RAN <NUM> or an Access Network (AN) as well as an Access and Mobility Function (AMF) <NUM>. Typically, the R(AN) <NUM> comprises base stations, e.g. such as eNBs or gNBs or similar. Seen from the core network side, the <NUM> Core (5GC) NFs shown in <FIG> include a NSSF <NUM>, an Authentication Server Function (AUSF) <NUM>, a UDM <NUM>, the AMF <NUM>, a Session Management Function (SMF) <NUM>, a PCF <NUM>, and an Application Function (AF) <NUM>.

Reference point representations of the <NUM> network architecture are used to develop detailed call flows in the normative standardization. The N1 reference point is defined to carry signaling between the UE <NUM> and AMF <NUM>. The reference points for connecting between the AN <NUM> and AMF <NUM> and between the AN <NUM> and UPF <NUM> are defined as N2 and N3, respectively. There is a reference point, N11, between the AMF <NUM> and SMF <NUM>, which implies that the SMF <NUM> is at least partly controlled by the AMF <NUM>. N4 is used by the SMF <NUM> and UPF <NUM> so that the UPF <NUM> can be set using the control signal generated by the SMF <NUM>, and the UPF <NUM> can report its state to the SMF <NUM>. N9 is the reference point for the connection between different UPFs <NUM>, and N14 is the reference point connecting between different AMFs <NUM>, respectively. N15 and N7 are defined since the PCF <NUM> applies policy to the AMF <NUM> and SMF <NUM>, respectively. N12 is required for the AMF <NUM> to perform authentication of the UE <NUM>. N8 and N10 are defined because the subscription data of the UE <NUM> is required for the AMF <NUM> and SMF <NUM>.

The 5GC network aims at separating user plane and control plane. The user plane carries user traffic while the control plane carries signaling in the network. In <FIG>, the UPF <NUM> is in the user plane and all other NFs, i.e., the AMF <NUM>, SMF <NUM>, PCF <NUM>, AF <NUM>, NSSF <NUM>, AUSF <NUM>, and UDM <NUM>, are in the control plane. Separating the user and control planes guarantees each plane resource to be scaled independently. It also allows UPFs to be deployed separately from control plane functions in a distributed fashion. In this architecture, UPFs may be deployed very close to UEs to shorten the Round Trip Time (RTT) between UEs and data network for some applications requiring low latency.

The core <NUM> network architecture is composed of modularized functions. For example, the AMF <NUM> and SMF <NUM> are independent functions in the control plane. Separated AMF <NUM> and SMF <NUM> allow independent evolution and scaling. Other control plane functions like the PCF <NUM> and AUSF <NUM> can be separated as shown in <FIG>. Modularized function design enables the 5GC network to support various services flexibly.

<FIG> illustrates a <NUM> network architecture using service-based interfaces between the NFs in the control plane, instead of the point-to-point reference points/interfaces used in the <NUM> network architecture of <FIG>. However, the NFs described above with reference to <FIG> correspond to the NFs shown in <FIG>. The service(s) etc. that a NF provides to other authorized NFs can be exposed to the authorized NFs through the service-based interface. In <FIG> the service based interfaces are indicated by the letter "N" followed by the name of the NF, e.g. Namf for the service based interface of the AMF <NUM> and Nsmf for the service based interface of the SMF <NUM>, etc. The NEF <NUM> and the NRF <NUM> in <FIG> are not shown in <FIG> discussed above. However, it should be clarified that all NFs depicted in <FIG> can interact with the NEF <NUM> and the NRF <NUM> of <FIG> as necessary, though not explicitly indicated in <FIG>.

Some properties of the NFs shown in <FIG> and <FIG> may be described in the following manner. The AMF <NUM> provides UE-based authentication, authorization, mobility management, etc. A UE <NUM> even using multiple access technologies is basically connected to a single AMF <NUM> because the AMF <NUM> is independent of the access technologies. The SMF <NUM> is responsible for session management and allocates Internet Protocol (IP) addresses to UEs. It also selects and controls the UPF <NUM> for data transfer. If a UE <NUM> has multiple sessions, different SMFs <NUM> may be allocated to each session to manage them individually and possibly provide different functionalities per session. The AF <NUM> provides information on the packet flow to the PCF <NUM> responsible for policy control in order to support Quality of Service (QoS). Based on the information, the PCF <NUM> determines policies about mobility and session management to make the AMF <NUM> and SMF <NUM> operate properly. The AUSF <NUM> supports authentication function for UEs or similar and thus stores data for authentication of UEs or similar while the UDM <NUM> stores subscription data of the UE <NUM>. The Data Network (DN), not part of the 5GC network, provides Internet access or operator services and similar.

Embodiments of the present disclosure more specifically relate to the 5GS appearing as a TSN bridge for integration with a TSN. In this regard, <FIG>, which is a reproduction of Figure <NUM>. <NUM>-<NUM> of Change Request (CR) S2-<NUM> for 3GPP TS <NUM>, shows one example of an architecture in which a 5GS appears as a TSN bridge <NUM>. The architecture includes a TSN AF <NUM>, a device side TT (DS-TT) <NUM>, and a network side TT (NW-TT) <NUM>. In this example, the TT at the UE side, which is denoted in <FIG> as the DS-TT <NUM> and also referred to herein as a UE side TT or UE/TT, is shown outside of the UE <NUM>, and the TT at the UPF side, which is denoted in <FIG> as the NW-TT <NUM> and also referred to herein as a UPF side TT or UPF/TT, is shown inside of the UPF <NUM>. However, in other embodiments, the DS-TT <NUM> at the UE side is alternatively implemented within the UE <NUM> and/or the NW-TT <NUM> at the UPF side is alternatively implemented outside of the UPF <NUM>.

Now, turning to some example embodiments of the present disclosure. Here, example embodiments are described for addressing Problems <NUM>-<NUM> described above. Note that while these embodiments are described separately for each problem, these solutions may be used independently or in any desired combination.

When the UE/TT <NUM> receives the "wanted domainNumber(s)" from the TSN end station(s) via (g)PTP announce messages, there can be different ways to deliver UE or end station (denoted herein as UE/end station) specific "wanted domainNumber(s)" inside the 5GS. The "wanted domainNumber(s)" is the indication(s) of the clock domain(s) in which the TSN end station(s) is(are) interested.

In some embodiments, a control plane way of delivering information about the clock domain(s) of interest (i.e. "wanted domainNumber(s)") for a given UE <NUM> (Announce message termination at the UE/TT <NUM>) is provided.

The UE/TT <NUM> or UE <NUM> can terminate the gPTP Announce messages, extract the "clock domain info" provided by the domainNumber(s) therein, and then deliver the extracted clock domain info using 5GS control plane signaling. Note that additional information provided by the Announce messages is also used to perform the Best Master Clock Algorithm (BMCA). BMCA is part of the (g)PTP standard (see, e.g., IEEE <NUM>, clause <NUM>. This is not further addressed by the present disclosure.

More specifically, <FIG> illustrates one example of a control plane way to convey "wanted domainNumber(s)" in 5GS in accordance with some embodiments of the present disclosure. Looking at <FIG>, the procedure for conveying "wanted domainNumber(s)" in 5GS in accordance with some embodiments of the present disclosure can be described as follows:.

In some embodiments, the UE/TT <NUM> or the UE <NUM> forwards (g)PTP announce messages to the RAN and the UPF <NUM> via user plane, e.g. in the Packet Data Convergence Protocol (PDCP) and General Packet Radio Service Tunneling Protocol (GTP) User Data (GTP-U) payload associated with a default PDU session. Processing of the BMCA related information is out of the scope of the present disclosure.

<FIG> illustrates one example of a user plane way to convey "wanted domainNumber(s)" in the 5GS in accordance with some embodiments of the present disclosure. Looking at <FIG>, the procedure for conveying "wanted domainNumber(s)" via the user plane in 5GS in accordance with some embodiments of the present disclosure can be described as follows:.

In some embodiments, the SMF <NUM> may know how many "wanted domainNumbers" are needed for a given gNB (i.e., based on the SMF <NUM> knowing the set of UEs managed by a given gNB and their respective "wanted domainNumber(s)"), and therefore may send this information directly to the gNB. The gNB may then apply domain filtering based on this information. The domain filter at a gNB may differ from that at the other gNB(s).

<FIG> illustrates one example of domain filtering at a gNB <NUM>. From right side of the <FIG>, all TSN clocks for all domains are sent using gPTP messages from the UPF <NUM> to the RAN (i.e., to the gNB <NUM>). The UPF <NUM> forwards the (g)PTP messages, including messages from different time domains, over a user plane GTP-U tunnel which already exists between the gNB <NUM> and the UPF <NUM>. Normal handling in the UPF <NUM> applies (i.e., the GTP-U tunnel is associated with a PDU session that has already been established for the target UE <NUM> and deemed appropriate for conveying gPTP messages as user plane information).

The gNB <NUM> sniffs the gPTP messages extracted from the GTP-U PDUs and discards all of them that do not indicate a DomainNumber that the SMF <NUM> has indicated to be of interest to at least one UE/end station.

Instead of using (g)PTP announce message to carry the "wanted domainNumber(s)", there are other ways to deliver the "wanted domainNumber(s)".

The signaling methods described here are not limited only for "wanted domainNumber(s)". The methods should apply for delivering other TSN related parameters inside the 5GS or between the 5GS and TSN network.

The 5GS signaling methods that are used to deliver "wanted domainNumber(s)" to relevant nodes are described herein. The signaling methods differ from case to case, i.e. when different nodes are to get the "wanted domainNumber(s)" information to perform the Domain filtering function. The signaling methods described here are not limited only for "wanted domainNumber(s)", the methods could apply for delivering other TSN related parameters inside the 5GS or between the 5GS and TSN network.

A way of delivering a time difference between the TSN clock and the <NUM> clock (T_diff_upf) from the UPF/TT to the gNB is as follows. The UPF/TT receives a gPTP message used for providing TSN clock information. The UPF/TT uses the precise Origintimestamp and correction values included in the TSN clock information to produce/recover the TSN clock value. The UPF/TT takes an ingress timestamp based on the <NUM> clock for the same incoming gPTP message. The UPF/TT then calculates the time difference (offset) between the ingress timestamp based on the <NUM> clock and the recovered TSN clock value to provide T_diff_upf. This T_diff_upf value is communicated to the gNB. The delivery of this information inside the 5GS can use this same signaling method. For example, using a control plane based method, the T_diff_upf can be reported from the UPF <NUM> to the SMF <NUM> or PCF <NUM> via N4 session management procedure, then the SMF <NUM> can relay it to the AMF <NUM> and RAN (i.e., gNB <NUM>) via NGAP. See, e.g., <FIG>.

Looking at <FIG>, the procedure is as follows:.

<FIG> is a schematic block diagram of a network node <NUM> according to some embodiments of the present disclosure. Optional components are represented here with dashed lines. The network node <NUM> may be, for example, radio access node (e.g., a base station <NUM> or <NUM> such as the gNB <NUM>) or a core network node (e.g., a node implementing a core network function such as, e.g., the UPF, a TT (e.g., UPF/TT), AMF, SMF, PCF, or AF). As illustrated, the network node <NUM> includes a control system <NUM> that includes one or more processors <NUM> (e.g., Central Processing Units (CPUs), Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs), and/or the like), memory <NUM>, and a network interface <NUM>. The one or more processors <NUM> are also referred to herein as processing circuitry. In addition, if the network node <NUM> is a radio access node, the network node <NUM> also includes one or more radio units <NUM> that each includes one or more transmitters <NUM> and one or more receivers <NUM> coupled to one or more antennas <NUM>. The radio units <NUM> may be referred to or be part of radio interface circuitry. In some embodiments, the radio unit(s) <NUM> is external to the control system <NUM> and connected to the control system <NUM> via, e.g., a wired connection (e.g., an optical cable). However, in some other embodiments, the radio unit(s) <NUM> and potentially the antenna(s) <NUM> are integrated together with the control system <NUM>. The one or more processors <NUM> operate to provide one or more functions of a network node <NUM> (e.g., a node implementing a core network function such as, e.g., the UPF, a TT (e.g., UPF/TT), AMF, SMF, PCF, or AF) as described herein. In some embodiments, the function(s) are implemented in software that is stored, e.g., in the memory <NUM> and executed by the one or more processors <NUM>.

<FIG> is a schematic block diagram that illustrates a virtualized embodiment of the network node <NUM> according to some embodiments of the present disclosure. Optional components are represented here with dashed lines. As used herein, a "virtualized" radio access node is an implementation of the network node <NUM> in which at least a portion of the functionality of the network node <NUM> is implemented as a virtual component(s) (e.g., via a virtual machine(s) executing on a physical processing node(s) in a network(s)). As illustrated, in this example, the network node <NUM> includes one or more processing nodes <NUM> coupled to or included as part of a network(s) <NUM> via the network interface <NUM>. Each processing node <NUM> includes one or more processors <NUM> (e.g., CPUs, ASICs, FPGAs, and/or the like), memory <NUM>, and a network interface <NUM>. Optionally, the network node <NUM> includes the control system <NUM> that includes the one or more processors <NUM> (e.g., CPUs, ASICs, FPGAs, and/or the like), the memory <NUM>, and the network interface <NUM> and, if it is a radio access node, the one or more radio units <NUM> that each includes the one or more transmitters <NUM> and the one or more receivers <NUM> coupled to the one or more antennas <NUM>, as described above. The control system <NUM> is connected to the radio unit(s) <NUM> via, for example, an optical cable or the like. If present, the control system <NUM> is connected to the one or more processing nodes <NUM>.

In this example, functions <NUM> of the network node <NUM> described herein (e.g., one or more functions of a node implementing a core network function such as, e.g., the UPF, a TT (e.g., UPF/TT), AMF, SMF, PCF, or AF) are implemented at the one or more processing nodes <NUM> or distributed across the control system <NUM> and the one or more processing nodes <NUM> in any desired manner. In some particular embodiments, some or all of the functions <NUM> of the network node <NUM> described herein are implemented as virtual components executed by one or more virtual machines implemented in a virtual environment(s) hosted by the processing node(s) <NUM>. As will be appreciated by one of ordinary skill in the art, additional signaling or communication between the processing node(s) <NUM> and the control system <NUM> is used in order to carry out at least some of the desired functions <NUM>. Notably, in some embodiments, the control system <NUM> may not be included, in which case the radio unit(s) <NUM> communicate directly with the processing node(s) <NUM> via an appropriate network interface(s).

In some embodiments, a computer program including instructions which, when executed by at least one processor, causes the at least one processor to carry out the functionality of network node <NUM> or a node (e.g., a processing node <NUM>) implementing one or more of the functions <NUM> of the network node <NUM> in a virtual environment according to any of the embodiments described herein is provided.

<FIG> is a schematic block diagram of the network node <NUM> according to some other embodiments of the present disclosure. The network node <NUM> includes one or more modules <NUM>, each of which is implemented in software. The module(s) <NUM> provide the functionality of the network node <NUM> described herein.

<FIG> is a schematic block diagram of a UE <NUM> according to some embodiments of the present disclosure. As illustrated, the UE <NUM> includes one or more processors <NUM> (e.g., CPUs, ASICs, FPGAs, and/or the like), memory <NUM>, and one or more transceivers <NUM> each including one or more transmitters <NUM> and one or more receivers <NUM> coupled to one or more antennas <NUM>. The transceiver(s) <NUM> includes radio front end circuitry connected to the antenna(s) <NUM> that is configured to condition signals communicated between the antenna(s) <NUM> and the processor(s) <NUM>, as will be appreciated by on of ordinary skill in the art. The processors <NUM> are also referred to herein as processing circuitry. The transceivers <NUM> are also referred to herein as radio circuitry. In some embodiments, the functionality of the UE <NUM> described above (functionality of the UE/TT) may be fully or partially implemented in software that is, e.g., stored in the memory <NUM> and executed by the processor(s) <NUM>. Note that the UE <NUM> may include additional components not illustrated in <FIG> such as, e.g., one or more user interface components (e.g., an input/output interface including a display, buttons, a touch screen, a microphone, a speaker(s), and/or the like and/or any other components for allowing input of information into the UE <NUM> and/or allowing output of information from the UE <NUM>), a power supply (e.g., a battery and associated power circuitry), etc..

Claim 1:
A method performed by a node that operates as a virtual Time Sensitive Networking, TSN, bridge (<NUM>) node, the node being either a User Equipment, UE, (<NUM>) in a cellular communications system (<NUM>) or a Time Sensitive Networking, TSN, Translator, TT, (<NUM>) associated with the UE (<NUM>), the method comprising:
receiving, from a TSN end station, a Precision Time Protocol, PTP, or Generalized PTP, gPTP, announce message comprising information that identifies plurality of clock domains for which the TSN end station desires to receive PTP or gPTP messages; and
sending, to a core network node in the cellular communications system (<NUM>) the information that identifies the plurality of clock domains extracted from the PTP or gPTP announce message,
wherein the information that identifies the plurality of clock domains comprises a plurality of wanted domain numbers that identify the plurality of clock domains for which the TSN end station desires to receive PTP or gPTP messages.