Patent Description:
A mobile radio communication system, such as a <NUM> mobile radio communication system, may be used to provide a Time-Sensitive Networking (TSN) Ethernet bridge according to IEEE <NUM>. For bridges according to IEEE <NUM>. 1Q functionalities like Cyclic Queuing and Forwarding are provided to enable synchronous traffic deterministic forwarding services.

In such a Time-Sensitive Networking Ethernet bridge data of TSN traffic flows is transported by the radio access network of the mobile radio communication system.

Efficient configuration of the radio access network for this task is desirable.

<NPL>) discloses methods and an apparatus for reporting clock drift between a TSN and a 5GS (5th generation mobile communication network) from the UPF and the SMF.

<NPL> discloses association procedures to connect time sensitive networks to a 5GS network.

"<NPL>, discloses a <NUM> System extended to support Time sensitive communication as defined in IEEE <NUM> Time Sensitive Networking (TSN) standards.

<CIT> discloses a TSN service processing method, apparatus and system.

According to one aspect of the present invention, a mobile radio communication system configured to provide a Time-Sensitive Networking Ethernet bridge is provided according to claim <NUM>. Additional features for advantageous embodiments of the present invention are provided in the dependent claims.

According to another aspect of the present invention, a method for providing a Time-Sensitive Networking Ethernet bridge in accordance with claim <NUM> is provided.

According to a further aspect of the present invention, a computer program and a computer readable medium in accordance with claim <NUM> is provided.

The following detailed description refers to the accompanying drawings that show, by way of illustration, specific details and aspects of this disclosure in which the invention may be practiced. Other aspects may be utilized and structural, logical, and electrical changes may be made without departing from the scope of the invention. The various aspects of this disclosure are not necessarily mutually exclusive, as some aspects of this disclosure can be combined with one or more other aspects of this disclosure to form new aspects.

In the following, various examples will be described in more detail.

<FIG> shows a radio communication system <NUM>, e.g. a <NUM> communication network as specified by 3GPP (Third Generation Partnership Project).

The radio communication system <NUM> includes a mobile radio terminal device <NUM> such as a UE (user equipment), a nano equipment (NE), and the like. The mobile radio terminal device <NUM>, also referred to as subscriber terminal, forms the terminal side while the other components of the radio communication system <NUM> described in the following are part of the mobile radio communication network side, i.e. part of a mobile (radio) communication network (e.g. a Public Land Mobile communication network PLMN).

Furthermore, the radio communication system <NUM> includes a radio access network <NUM>, which may include a plurality of radio access network nodes, i.e. base stations configured to provide radio access in accordance with a <NUM> (Fifth Generation) radio access technology (<NUM> New Radio). It should be noted that the radio communication system <NUM> may also be configured in accordance with LTE (Long Term Evolution) or another radio communication standard (e.g. Wi-Fi) but <NUM> is herein used as an example. Each radio access network node may provide a radio communication with the mobile radio terminal device <NUM> over an air interface. It should be noted that the radio access network <NUM> may include any number of radio access network nodes.

The radio communication system <NUM> further includes a core network <NUM> including an Access and Mobility Management Function (AMF) <NUM> connected to the RAN <NUM>, a Unified Data Management (UDM) <NUM> (which may be paired with a Unified Data Repository (UDR)) and a Network Slice Selection Function (NSSF) <NUM>. Here and in the following examples, the UDM may further consist of the actual UE's subscription database, which is known as, for example, the UDR (Unified Data Repository). The core network <NUM> further includes an AUSF (Authentication Server Function) <NUM> and a PCF (Policy Control Function) <NUM>.

The core network <NUM> may have multiple network slices <NUM>, <NUM> and for each network slice <NUM>, <NUM>, the operator may create multiple network slice instances (NSIs) <NUM>, <NUM>. For example, the core network <NUM> includes a first core network slice <NUM> with three core network slice instances (CNIs) <NUM> for providing Enhanced Mobile Broadband (eMBB) and a second core network slice <NUM> with three core network slice instances (CNIs) <NUM> for providing Vehicle-to-Everything (V2X).

Typically, when a network slice is deployed, network functions (NFs) are instantiated, or (if already instantiated) referenced to form a network slice instance (NSI) and network functions that belong to a network slice instance are configured with a network slice instance identification.

Specifically, in the shown example, each instance <NUM> of the first core network slice <NUM> includes a first Session Management Function (SMF) <NUM> and a first User Plane Function (UPF) <NUM> and each instance <NUM> of the second core network slice <NUM> includes a second Session Management Function (SMF) <NUM> and a second User Plane Function (UPF) <NUM>.

The core network <NUM> may further include an NRF (Network Repository Function) <NUM>, which provides network function/network function service registration, network function/network function service discovery. The NRF may have an interface to any network function in the mobile radio communication network side, e.g. have an interface to the AMF <NUM>, the SMFs <NUM>, <NUM>. For simplicity, only the interface between the NRF <NUM> and the AMF <NUM> is depicted.

The radio communication system <NUM> may further include an OAM (Operation, Administration and Maintenance) function (or entity) <NUM>, e.g. implemented by one or more OAM servers which is connected to the RAN <NUM> and the core network <NUM> (connections are not shown for simplicity).

Further, the radio communication system <NUM> may include a NWDAF (Network Data and Analytics Function) <NUM>.

A <NUM> communication system (abbreviated as 5GS) may in particular be used to provide an Ethernet bridge. This is illustrated in <FIG>.

<FIG> shows an Ethernet bridge <NUM> implemented by a <NUM> communication system.

Specifically, the Ethernet bridge <NUM> is implemented by one or more UEs <NUM>, for example corresponding to UE <NUM>, a RAN <NUM> (i.e. one or more base stations), for example corresponding to RAN <NUM> and a UPF <NUM>, for example corresponding to a UPF <NUM>, <NUM>.

The <NUM> system arrangement (i.e. the arrangement of UEs <NUM>, RAN <NUM> and UPF <NUM>) is seen as an Ethernet bridge by other TSN nodes <NUM>, <NUM> (which may themselves be Ethernet bridges). An application is for example in a factory where the UEs are part of mobile robots (acting as TSN end nodes <NUM>) and a stationary robot controller acts as TSN bridge node <NUM> and is connected via Ethernet with the mobile robots.

Each UE <NUM> is combined with (i.e. implements) a DS-TT (Device-side TSN translator) <NUM>. It should be noted that that this is only an example and whether DS-TT and UE are combined or are separate is up to implementation.

Each DS-TT <NUM> implements an Ethernet port to which a next TSN node <NUM> is connected.

The UPF <NUM> is combined with (i.e. implements) a NW-TT (Network-side TSN translator) <NUM>. The NW-TT <NUM> implements one or more Ethernet ports where the next TSN nodes <NUM> are connected.

Each UE <NUM> sets up an Ethernet type PDU session <NUM> towards the UPF <NUM>. Each PDU session <NUM> is associated with one DS-TT <NUM>. One or more PDU sessions <NUM> are setup with the UPF <NUM>. The Ethernet type PDU sessions <NUM> convey Ethernet frames between the UEs <NUM> and the UPF <NUM>. The UPF <NUM> (or more specifically the NW-TT <NUM>) routes each Ethernet frame based on its destination MAC (Medium Access Control) address (and VLAN (Virtual Local Area Network) ID) in the frame to the corresponding egress ports. In DL direction the NW-TT <NUM> routes the frame to a PDU session <NUM> associated with the corresponding DS-TT port. In UL direction the NW-TT <NUM> routes the frame to a corresponding NW-TT port.

Thus, when implemented by a 5GS, the IEEE <NUM>. 1Q Ethernet bridge functionality is split between NW-TT <NUM> and DS-TT <NUM>, which are connected via a PDU session <NUM>. In particular, the actions in the frame forwarding process as defined in IEEE <NUM>. 1Q are split between DS-TT <NUM> and NW-TT <NUM>.

A CNC (Centralized Network Configuration) entity in the (bridge-) external TSN network can configure the 5GS virtual bridge <NUM> via an API (Application Programming Interface) exposed by a TSN Application Function (AF) in the 5GS. The TSN AF distributes the bridge configuration to the UEs <NUM> (specifically the DS-TTs <NUM>) and the UPF <NUM> (specifically the NW-TT <NUM>) using a transparent container via PCF <NUM> and SMF <NUM>, <NUM>.

<FIG> illustrates the involvement of a CNC and a TSN AF and further 5GS components in the provision of an Ethernet bridge <NUM> implemented by a <NUM> communication system.

As described with reference to <FIG>, the Ethernet Bridge <NUM> is implemented by a UE <NUM>, a RAN, here represented by a base station <NUM>, and a UPF <NUM>. The UE <NUM> implements a DS-TT <NUM>. The UPF <NUM> implements a NW-TT <NUM>.

Further, an SMF <NUM>, e.g. corresponding to SMF <NUM> or <NUM>, a PCF <NUM>, e.g. corresponding to PCF <NUM>, a TSN AF <NUM> and a CNC <NUM> are involved in the implementation and provision of the Ethernet bridge <NUM>.

In this example, the DS-TT <NUM> is coupled to a first TSN Host <NUM> (TSN end node) and the NW-TT <NUM> is coupled via two TSN bridges <NUM> to a second TSN Host <NUM> (TSN end node).

The TSN Translators (i.e. DS-TT <NUM> and NW-TT <NUM>) interconnect the IEEE TSN System and the <NUM> System. The TTs <NUM>, <NUM> perform time-aware scheduling and per-stream filtering and policing (PSFP): this includes timing of the TSN traffic streams.

The CNC <NUM> controls the scheduling of TSN data streams in the 5GS Ethernet bridge <NUM>. The TSN AF <NUM> maps corresponding configuration information for configuration of the Ethernet bridge <NUM> from the IEEE data format used to a data format understandable by the 5GS.

The 5GS Ethernet bridge <NUM> can be connected to multiple TSN time domains.

<FIG> illustrates the connection of a 5GS Ethernet bridge <NUM> to multiple time domains.

As in <FIG>, the 5GS Ethernet bridge <NUM> is implemented by a UE <NUM>, a RAN, here represented by a base station <NUM>, a UPF <NUM>, an SMF <NUM>, a PCF <NUM>, a TSN AF <NUM> and a CNC <NUM>. The UE <NUM> implements a DS-TT <NUM>. The UPF <NUM> implements a NW-TT <NUM>.

In this example, the DS-TT <NUM> is coupled to a first TSN Host <NUM> (TSN end node). The NW-TT <NUM> is coupled to multiple second TSN Hosts (not shown), in this example via two TSN bridges <NUM>.

The second TSN Hosts are assumed to be part of different TSN time domains. Thus, the Ethernet bridge is connected to multiple TSN time domains. Each time domain has a respective Grand Master (GM) <NUM>, <NUM> that sends gPTP Sync messages (i.e. synchronisation information). The 5GS processes them independently. Specifically, the DS-TT and NW-TT process the gPTP messages for time synchronization
For example, the first Grand Master <NUM> is associated with time domain <NUM> and the second Grand Master <NUM> is associated with time domain <NUM>.

One time domain (e.g. time domain <NUM>) is the TSN time domain used by the CNC <NUM>. Traffic timing information is given by the TSN AF <NUM> in this TSN time domain. Accordingly, the traffic scheduling information (of the time-aware scheduling) and PSFP is expressed to the TTs <NUM>, <NUM> using this time domain. The TTs <NUM>, <NUM> are synchronized using the 5GS clock. TTs <NUM>, <NUM> convert the timing in time-aware scheduling and PSFP from the TSN time domain used by the CNC <NUM> to 5GS time before executing the instructions of time-aware scheduling and PSFP.

The NW-TT <NUM> (i.e. the UPF <NUM>) measures the clock differences between 5GS time and TSN time, and may report the clock differences to the SMF in clock drifting reports (which may, according to one embodiment, also include clock offset information besides clock drift information or only clock offset information).

The SMF <NUM> may thus adjust the timing (i.e. in this example Burst Arrival Time (BAT) and Periodicity) for the QoS (Quality of Service) Flows used by the RAN (gNB <NUM>) to forward the traffic based on clock drifting reports provided by the UPF <NUM>. The SMF <NUM> composes the adjusted timing information into TSC Assistance Information (TSCAI) which it sends to the RAN (gNB <NUM>), along with the QoS information associated with the QoS Flows. The gNB <NUM> adjusts the timing of the radio resource allocation for QoS Flows based on the TSCAI.

The SMF <NUM> may indicate the TSN time domains to the UPF <NUM> for which the SMF <NUM> wants to receive clock drifting reports. The UPF <NUM> provides clock drifting reports for each of the indicated TSN time domains to the SMF <NUM>.

However, the SMF <NUM> does typically not know which is the TSN time domain used by the CNC <NUM>. Therefore, it is not clear which TSN time domains the SMF <NUM> should indicate to the UPF <NUM> to be provided with clock drifting reports it may use to adjust the TSCAI that it sends sent to the gNB <NUM>.

For efficiency of operation, the SMF <NUM> should use the TSN time domain used by the CNC as a basis for TSCAI adjustments. Accordingly, the SMF <NUM> should indicate this TSN time domain to the UPF <NUM> to be provided with clock drifting reports. However, while the TSN time domain used by the CNC <NUM> is configured for the TTs (i.e. the TTs know which time domain is the one used by the CNC <NUM>), this is not known by the SMF <NUM>.

According to various embodiments, the SMF <NUM> therefore requests the UPF <NUM> to provide a clock drifting report (or clock drifting reports) for the "configured time domain", i.e. for the time domain for which it is included in the configuration of the NW-TT <NUM> (and thus also the UPF <NUM>) that this is the time domain used by the CNC <NUM>. The UPF <NUM> then determines the correct time domain and provides clock difference (drift and/or offset) for that time domain.

If, for example the CNC uses time domain <NUM>, the UPF <NUM> provides a clock drifting report for time domain <NUM> in response to the SMF's request to provide a clock drifting report for the "configured time domain".

<FIG> shows a flow diagram <NUM> illustrating a control of a RAN for provision of an Ethernet bridge.

A TSN AF <NUM>, e.g. corresponding to TSN AF <NUM>, an SMF <NUM>, e.g. corresponding to SMF <NUM>, and a UPF <NUM>, e.g. corresponding to UPF <NUM>, are involved in the flow.

The TSN AF <NUM> sends QoS requests for multiple TSN traffic flows for which the Ethernet bridge <NUM> provides QoS flows. For all TSN traffic flows, the TSN AF <NUM> indicates BAT and periodicity in the "configured time domain", i.e. in the time domain used by the CNC <NUM>.

The SMF <NUM> maintains a list of the QoS flows with the indicated BAT and periodicity.

The SMF <NUM> requests a clock drifting report for the "configured time domain" from the UPF <NUM>. The UPF <NUM> performs clock drifting measurements and provides a clock drifting report for the "configured time domain" to the SMF <NUM>.

The SMF <NUM> then adjusts BAT and periodicity for all QoS flows in accordance with the information in the clock drifting report and provides this adjusted timing information to the RAN.

In summary, according to various embodiment, a mobile radio communication system is provided as illustrated in <FIG>.

<FIG> shows a mobile radio communication system <NUM> providing a Time-Sensitive Networking Ethernet bridge according to an embodiment.

The mobile radio communication system <NUM> includes a radio access network <NUM> and a user plane component <NUM> configured to provide a network-side Time-Sensitive Networking translator <NUM> for the Time-Sensitive Networking Ethernet bridge.

The mobile radio communication system <NUM> further includes a user plane control component <NUM> configured to receive timing information for at least one traffic flow to be communicated via the Time-Sensitive Networking Ethernet bridge, wherein the timing information is specified with respect to a predefined Time-Sensitive Networking time domain of a plurality of time domains for which the mobile radio communication system is configured to receive synchronisation information.

The user plane control component <NUM> is further configured to send a request <NUM> to the user plane component for information about a difference between a clock of the predefined Time-Sensitive Networking time domain and a clock of the mobile radio communication system.

The user plane component <NUM> is configured to determine the time domain among the plurality of time domains corresponding to the predefined time domain, determine information <NUM> about a difference between the clock of the determined time domain and the clock of the mobile radio communication system and provide the determined information <NUM> to the user plane control component <NUM> in response to the request <NUM>.

The user plane control component <NUM> is configured to configure the radio access network in accordance with the determined information.

According to various embodiments, in other words, a user plane control component (e.g. SMF) requests a user plane component (e.g. UPF) to provide clock drifting (or offset) information between a mobile radio communication system's (internal) clock and TSN time domain in which the user plane control component receives timing information (e.g. from a CNC). The user plane component determines the correct time domain and provides the user plane component with the requested information. The user plane control component does not have knowledge about which time domain of the plurality of time domains is the one in which it receives the timing information and therefore the request does not include a specific indication (such as a number or identity) of the time domain.

The user plane component, however, is configured to derive the correct time domain and provides the user plane control component with the correct clock information.

The approach of <FIG> allows improving the accuracy of the timing of the radio resource allocation for a TSN traffic flow. More accurate timing of the radio resource allocation decreases the latency of the TSN traffic flow since the time to buffer the packet in the UE (UL direction) or gNB (DL direction) decreases.

In various embodiments, a method is performed (e.g. by a mobile radio communication system) as illustrated in <FIG>.

<FIG> shows a flow diagram <NUM> illustrating a method for providing a Time-Sensitive Networking Ethernet bridge.

In <NUM> a user plane control component receives timing information in for at least one traffic flow to be communicated via the Time-Sensitive Networking Ethernet bridge, wherein the timing information is specified with respect to a predefined Time-Sensitive Networking time domain of a plurality of time domains for which the mobile radio communication system is configured to receive synchronisation information.

In <NUM> a request is sent from the user plane control component to a user plane component for information about a difference between a clock of the predefined Time-Sensitive Networking time domain and a clock of the mobile radio communication system. The user plane component to which the request is sent is a user plane component that provides a network-side Time-Sensitive Networking translator for the Time-Sensitive Networking Ethernet bridge.

In <NUM> the user plane component determines the time domain among the plurality of time domains corresponding to the predefined time domain, determines information about a difference between the clock of the determined time domain and the clock of the mobile radio communication system in <NUM> and provides the determined information to the user plane control component in response to the request in <NUM>.

In <NUM> the user plane control component configures the a radio access network in accordance with the determined information.

According to various embodiments, in other words, a method for provision of clock drifting information is provided, including the configuration of a time domain number in a user plane entity, the user plane entity receiving a request for clock drifting information between the configured time domain number and an internal clock in a mobile radio communication system from the user plane control entity, the user plane entity, based on the request, measuring clock drifting between the configured time domain number and the internal clock in the mobile system and reporting the measurement to the user plane control entity.

The user plane control entity may maintain timing information for traffic flows and the user plane control entity may adjust the timing information for the traffic flows based on the clock drifting information from the user plane entity.

Claim 1:
A mobile radio communication system (<NUM>) configured to a provide a Time-Sensitive Networking Ethernet bridge (<NUM>) and comprising:
A radio access network (<NUM>, <NUM>, <NUM>);
A user plane component (<NUM>, <NUM>, <NUM>, <NUM>) configured to provide a network-side Time-Sensitive Networking translator (<NUM>, <NUM>, <NUM>, <NUM>) for the Time-Sensitive Networking Ethernet bridge (<NUM>); and
a user plane control component (<NUM>, <NUM>) configured to
receive (<NUM>) timing information for at least one traffic flow to be communicated via the Time-Sensitive Networking Ethernet bridge (<NUM>), wherein the timing information is specified with respect to a predefined Time-Sensitive Networking time domain of a plurality of time domains for which the mobile radio communication system (<NUM>) is configured to receive synchronisation information; and
send (<NUM>) a request to the user plane component (<NUM>, <NUM>, <NUM>, <NUM>) for information about a difference (<NUM>) between a clock of the predefined Time-Sensitive Networking time domain and a clock of the mobile radio communication system (<NUM>),
wherein the user plane component (<NUM>, <NUM>, <NUM>, <NUM>) is configured to determine (<NUM>), in response to the request of the user plane control component (<NUM>),
the time domain configured in the network-side Time Sensitive Networking translator (<NUM>, <NUM>, <NUM>, <NUM>) among the plurality of time domains corresponding to the predefined Time-Sensitive Networking time domain, determine (<NUM>) information about a difference (<NUM>) between the clock of the determined time domain and the clock of the mobile radio communication system(<NUM>) and provide (<NUM>) the determined information to the user plane control component (<NUM>, <NUM>) in response to the request; and
wherein the user plane control component (<NUM>, <NUM>) is configured to configure (<NUM>) the radio access network (<NUM>, <NUM>, <NUM>) in accordance with the determined information.