Patent Description:
Some example embodiments may generally relate to mobile or wireless telecommunication systems, such as Long Term Evolution (LTE) or fifth generation (<NUM>) radio access technology or new radio (NR) access technology, or other communications systems. For example, certain example embodiments may relate to apparatuses, systems, and/or methods for working clock determination for a mobile user equipment.

Examples of mobile or wireless telecommunication systems may include the Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (UTRAN), Long Term Evolution (LTE) Evolved UTRAN (E-UTRAN), LTE-Advanced (LTE-A), MulteFire, LTE-A Pro, and/or fifth generation (<NUM>) radio access technology or new radio (NR) access technology. Fifth generation (<NUM>) wireless systems refer to the next generation (NG) of radio systems and network architecture. <NUM> is mostly built on a new radio (NR), but the <NUM> (or NG) network can also build on E-UTRAN radio. It is estimated that NR will provide bitrates on the order of <NUM>-<NUM> Gbit/s or higher, and will support at least enhanced mobile broadband (eMBB) and ultra-reliable low-latency-communication (URLLC) as well as massive machine type communication (mMTC). NR is expected to deliver extreme broadband and ultra-robust, low latency connectivity and massive networking to support the Internet of Things (IoT). With IoT and machine-to-machine (M2M) communication becoming more widespread, there will be a growing need for networks that meet the needs of lower power, low data rate, and long battery life. It is noted that, in <NUM>, the nodes that can provide radio access functionality to a user equipment (i.e., similar to Node B in UTRAN or eNB in LTE) are named gNB when built on NR radio and named NG-eNB when built on E-UTRAN radio.

<CIT> (<CIT>) discloses a method, performed by a transmitting device in a wireless communication system, for handling generalized Precise Timing Protocol, gPTP, signaling, from a Time Sensitive Network, TSN. The transmitting device receives a gPTP message from a TSN network. The gPTP message comprises time information and a time domain related to the time information. The transmitting device extracts the time information and the time domain from the gPTP message. The transmitting device transmits a 3GPP message to a receiving device. The 3GPP message comprises the time information and the time domain related to the time information.

<CIT> (<CIT>) also discloses gPTP and TSN The gPTP frame comprises time information, an indication of a time domain related to the time information and/or a Medium Access Control (MAC) address of a second end station connected to a receiving device. Based on the indication of the time domain and/or the MAC address, the transmitting device determines the receiving device which the gPTP frame relates to. The transmitting device transmits, to the determined receiving device, the gPTP frame in a PDU session related to the determined receiving device.

The scope of protection is merely defined by the claims.

It will be readily understood that the components of certain example embodiments, as generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations. The following is a detailed description of some example embodiments of systems, methods, apparatuses, and computer program products for working clock determination for a mobile user equipment (UE).

For example, the usage of the phrases "certain embodiments," "an example embodiment," "some embodiments," or other similar language, throughout this specification refers to the fact that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment. Thus, appearances of the phrases "in certain embodiments," "an example embodiment," "in some embodiments," "in other embodiments," or other similar language, throughout this specification do not necessarily refer to the same group of embodiments, and the described features, structures, or characteristics may be combined in any suitable manner in one or more example embodiments.

Additionally, if desired, the different functions or procedures discussed below may be performed in a different order and/or concurrently with each other. Furthermore, if desired, one or more of the described functions or procedures may be optional or may be combined. As such, the following description should be considered as merely illustrative of the principles and teachings of certain example embodiments, and not in limitation thereof.

The <NUM> network with time sensitive networking (TSN)/time synchronization support may include integration of two types of synchronization clocks such as, for example, a global time domain and working clock domains. According to certain example embodiments, the global time domain may represent a <NUM> clock, and the working clock domains may represent vertical time domains. Furthermore, a specific time domain (TD) may include devices that may cooperate in the physical world. This may include, for example, robots, automated guided vehicles (AGVs), conveyor belts, and others. In certain example embodiments, TDs may be independent from each other, especially with respect to time scale and precision of time synchronization.

Some clock synchronization service level requirements, e.g., as specified by <NUM>rd Generation Partnership Project (3GPP), may be associated to the global time domain and working clock domain support in <NUM>. Such requirements may include, for example, the <NUM> system supporting networks with up to <NUM> working clock domains (with different synchronization domain identifiers/domain numbers), including for UEs connected through the <NUM> network. Another requirement may include the <NUM> system providing an interface at the UE to determine and to configure the precision and the time scale of the working clock domain. A further requirement may include the <NUM> system providing a suitable means to support the management of the merging and separation of working clock domains. The provided means may be interoperable with the corresponding mechanisms of TSN.

3GPP specifications may also include similar service requirements for the management of merging and separation of working clock domains as those mentioned above. The rationale is a common deployment for a general <NUM> network infrastructure serving an industrial/energy/automation use case, which does not map to the structure of the processes running in the use case. In other words, the user plane function (UPF) and the serving gNB may provide service to several UEs that may work with different TDs, which may lead to a situation where multiple TDs communicate through the same UPF/gNB.

3GPP specifications describe support for TSN time synchronization provided by the <NUM> system (5GS). For instance, the 5GS may have two synchronization processes: <NUM>) 5GS synchronization, and <NUM>) TSN domain synchronization. Each synchronization process may be considered independent from each other, and in certain cases, the gNB may be synchronized to the <NUM> grand master (GM) clock. The 5GS synchronization may be used for synchronization of nodes within the 3GPP system including, for example, between <NUM> radio access network (RAN) and UPF. The 5GS synchronization may also be used for synchronization of nodes within <NUM> RAN including, for example, between a gNB and a UE. In addition, <NUM> RAN synchronization between the gNB and UE may be achieved via reference time information signaling. As for TSN domain synchronization, this may provide synchronization service to a TSN network, and the process may follow IEEE specifications.

In certain cases, when multiple working clock domains are supported, 3GPP specifications describe that the UPF/network side TSN translator (NW-TT) may send generic precision time protocol (gPTP) messages or PTP messages for the domains to the UE(s)/device side TSN translator(s) (DS-TT) in the protocol data unit (PDU) sessions. If PTP is considered, instead of TSN application function (AF) being the AF, if it is gPTP, then TSN AF may apply. In addition, the UE may forward information related to all the working clock domain as-is to the connected DS-TT(s) that synchronizes with the (g)PTP message that it may need based on a domain number supported by the end device, and the domain number carried by the (g)PTP message. However, this may be wasteful of network and spectral resources as it can unnecessarily increases the size of the user plane (UP) payload. In case of TSN traffic, time bound transmission may be critical and, thus, increased payload may consume unnecessary radio resources for transmission, which risks late delivery and UP congestion.

<FIG> illustrates an example of a multiple clock domain scenario in a communication network. Integration of TSN/time synchronization support and <NUM> wireless networks may be affected by mobility. For instance, mobile TSN devices may move around (e.g., different factory floors where different working clock domains are utilized). As illustrated in <FIG>, such devices, even though they may require a broad set of clock domains at different times, may at certain times require a single or a subset of the clock domains to be provided to them depending on their current location. An assumption by 3GPP is that the DS-TT may know which time domain number is supported. Thus, the end station may know which clock domain to use at a particular time.

According to certain example embodiments, TDs of interest may be introduced for the UE as part of the PDU session management to optimize time information distribution to the UEs. In certain example embodiments, by using the available TDs, the <NUM> core (5GC) may update the UP configuration to provide the UE with just the synchronization messages for the TD(s) that may be needed by the UE. That is, in certain example embodiments, the UPF may be able to dynamically determine the TD(s) for which synchronization messages may need to be forwarded to a UE based on a combination of parameters including, for example, mobility events, location, and/or traffic inspection. According to certain example embodiments, the mobility events may correspond to mobility of the UE. For example, the UE may be changing the serving cell when the signal is stronger in the target cell than the source cell. Further in certain example embodiments, in the case of traffic inspection, if the UPF detects two UEs talking/communicating between each other (inspecting user plane traffic), and the UPF knows the TDs both UEs can work with, the traffic inspection can help determine the TD the UEs should receive.

In certain example embodiments, a session management function (SMF) may configure the UPF to enable the determination of the correct mapping between TD(s) and UE(s). To do so, the SMF may have two sources of information. One source of information may be provided by the UE. For instance, the UE may provide TD(s) information during PDU session management procedures (e.g., PDU session establishment or modification). Another source of information may be provided by a TSN application function (TSN AF). For example, the TSN AF may provide TD(s) information via a policy control function (PCF).

According to certain example embodiments, the TD (or working clock domain) determination at the UPF may be configured in various ways. For instance, one option may include the UE/DS-TT providing the required working clock domain numbers to the SMF during a PDU session establishment procedure. Once received, the SMF may forward this information to the UPF/NW-TT for the given PDU session, which enables the UPF/NW-TT to have knowledge of the domain number(s) that may be needed for a given UE/DS-TT PDU session. When the UPF/NW-TT receives a (g)PTP message containing time information related to a certain clock domain number, it may determine, based on information received from the SMF, whether a (g)PTP message needs to be sent to the given UE/DS-TT for a given PDU session. If the given UE/DS-TT needs the (g)PTP message, the UPF may include the corresponding (g)PTP message. If the given UE/DS-TT does not need the (g)PTP message, the UPF will not send it for the corresponding UE/DS-TT.

Certain example embodiments may provide another option to configure the TD determination at the UPF. For example, the TSN AF may obtain information about the mapping between the time domain in the (g)PTP message and the UEs/DS-TTs subscribed to this time domain either from the best master clock algorithm (BMCA) outcome or from the external configuration. In certain example embodiments, this mapping information may be given to the SMF through the PCF. Further, the SMF may associate the mapping information to the PDU sessions of the corresponding UEs/DS-TT, and configure the UPF accordingly. For instance, in certain example embodiments, the UPF may be configured by the SMF using N4 rules. According to certain example embodiments, the N4 rules may include packet detection rules (PDR) that may contain information to classify traffic (PDU(s)) arriving at the UPF. The N4 rules may also include forwarding action rules (FAR), quality of service (QoS) enforcement rules (QER), etc. Based on the associated PDU sessions and the time domain information (e.g., mapping information), the UPF/NW-TT may deliver the (g)PTP message to the corresponding UEs PDU sessions.

According to certain example embodiments, a further option to configure the TD determination at the UPF may be provided. In the above-mentioned solution, the BMCA outcome and hence the mapping information, may be available at the NW-TT. However, in other example embodiments, the NW-TT may provide the mapping information to the SMF either via UPF or via AF (or TSN AF). Then the association of the mapping information to the PDU sessions and configuration at the UPF may be performed as described above with respect to the SMF association of the mapping information to the PDU sessions, and the UPF/NW-TT delivering the (g)PTP message to the corresponding UE/DS-TT(s) PDU sessions. In other example embodiments, another option may be that the NW-TT by itself forwards the (g)PTP messages to the appropriate UE/DS-TT(s) transparently through 5GS using the BMCA outcome/mapping information.

<FIG> illustrates a signal diagram of user plane function (UPF) - triggered dynamic management of a time domain (TD) forwarding, according to certain example embodiments. As illustrated in <FIG>, certain example embodiments may provide dynamic management of TD(s) of interest for the UE at the UPF. At <NUM>, the UE may establish a PDU session with gNB1 and the UPF. At <NUM>, the UE's TDs and the related triggers may already be configured for the UE at the UPF and, at <NUM>, the NW-TT may receive various (g)PTP packets associated with respective TDs (e.g., TD #<NUM>, TD #<NUM>, and TD #<NUM>). According to certain example embodiments, the (g)PTP packets may include a domainNumber that identifies the TD. In addition, the contents of the (g)PTP message may include a message type, timestamp, domainNumber, correctionField, sequence ID, flags, etc. At <NUM>, the UPF/NW-TT may inspect the (g)PTP packets, and forward the (g)PTP packet with the TD that the UE may need (e.g., (g)PTP packet (TD #<NUM>)) to gNB1. At <NUM>, gNB1 may forward the (g)PTP packet (TD #<NUM>) to the UE.

As further illustrated in <FIG>, at <NUM>, the UE's movement may trigger handover from gNB <NUM> to gNB2. At <NUM>, the UPF may determine that the UE needs another TD and, at <NUM>, the NW-TT may receive various (g)PTP packets with respective TDs (e.g., TD #<NUM>, TD #<NUM>, and TD #<NUM>). At <NUM>, the UPF/NW-TT may inspect the (g)PTP packets, and forward the (g)PTP packet with the TD that the UE needs (e.g., (g)PTP packet (TD #<NUM>)) to gNB2. At <NUM>, (g)NB2 may forward the (g)PTP packet (TD #<NUM>) to the UE.

As illustrated in <FIG>, in certain example embodiments, the mapping between the UEs and TDs may be updated in case the UE is moving. For instance, the UE may be moving around different factory floors, or may be interacting with UEs/devices utilizing different TDs. According to certain example embodiments, updating the mapping between the UEs and TDs may be triggered by the UE/AGV based on its location in the network. For example, the UE/AGV may be entering a new cell, entering a predefined zone determined based on the position determined based on a 3GPP positioning system, or knowledge of clock domain being used by other UEs in the vicinity (e.g., signaled by the gNB, or advertised by the UEs over sidelink).

According to other example embodiments, the updating may be triggered the UPF itself. For example, the updating may be triggered by the UPF based on certain mobility events such as handover indication from the gNB/SMF, based on the UE changing its serving UPF, or upon receiving the frame for/from the UEs in the vicinity from/for the AGV. In this case, the UPF may need to be aware of the overall list of TDs the UE is subscribed to, and of the TDs which are used in a certain network location. According to further example embodiments, the updating of the mapping between the UEs and TDs may be signaled from the TSN controller via NW-TT. For example, this may be done based on the knowledge of the location of the AGV by the TSN controller.

<FIG> illustrates a signal diagram for configuring the UPF, according to certain example embodiments. As illustrated in <FIG>, at <NUM>, a PDU session may be stablished with the UPF, and the UE TDs may be indicated using non-access stratum (NAS) signaling. In particular, at <NUM>, the UE may trigger a session management procedure (i.e., modification or establishment) to provide TDs information to the network. In some example embodiments, the TDs information may be encapsulated within a NAS information element, and it may be transparently forwarded by the gNB and AMF to the SMF. At <NUM>, during PDU session establishment, the SMF may configure the TDs that the UPF will forward per PDU session or UE. For example, in certain example embodiments, the SMF may reconfigure the UPF user plane processing (i.e., N4 rules) to ensure that the UEs are receiving the TDs (e.g., via packet detection rules). Further, the configuration of the TDs may refer to sending the TDs information to the UPF so that the UPF is aware of the domain numbers that may be needed for a given UE/PDU session.

In certain example embodiments, the SMF may forward the TDs information related to certain UE and/or PDU session to the UPF during the configuration. For instance, according to certain example embodiments, the SMF may manage the TDs the UPF needs to forward to every UE. In addition, the UPF may learn, based on the traffic flows the UEs are exchanging, what TDs should be used. Further, in the SMF managing the TDs and the UPF learning, the SMF may provide some initial configuration, and the UPF may update the information and notify the SMF. In certain example embodiments, the TDs information may include triggers to switch the TD to forward to a UE, forwarding rules, or updates in the association between TD(s), UEs, and PDU sessions. For instance, in certain example embodiments, the triggers may include the detected traffic the UPF is forwarding per UE, or it could be an on demand requested by the SMF due to a location change of the UE reported by the AMF. Alternatively, there may be a temporal window the UE should be synchronized to a specific TD, or due to a new request done by the TSN AF or AF. According to certain example embodiments, the information exchanged may impact the packet forwarding control protocol (PFCP) between SMF and UPF to include extensions for the new set of information (e.g., new set of TDs information and possible triggers or policies to switch between the TDs). Additionally, the SMF may be subscribed to mobility events to obtain updates from the access and mobility management function (AMF), and report to the UPF if needed.

At <NUM>, using the information obtain at <NUM>, the UPF may update the local information associating TD(s) and UEs. According to certain example embodiments, the local information may include the mapping between the TDs and the UEs, the policies to switch between TDs, triggers to report to the SMF, etc. In particular, the UPF/NW-TT may determine (e.g., based on mobility events, location, etc.) the TD to forward to a PDU session. According to certain example embodiments, at <NUM>, the UPF may maintain a local table with the association between TDs numbers and PDU sessions. At <NUM>, the NW-TT may receive (g)PTP packets with TD #<NUM>, TD #<NUM>, and TD #<NUM>. Further, at <NUM>, the UPF/NW-TT may inspect the (g)PTP packets, and forward the TD (e.g., TD #<NUM>) the UE needs. In particular, when a (g)PTP packet is received in the UPF/NW-TT, the TD number may be read, and the packet may be forwarded to the matching PDU sessions the UPF has configured.

<FIG> illustrates another signal diagram for configuring the UPF, according to certain example embodiments. At <NUM>, the TSN AF may obtain the information about the mapping between UEs/DS-TT(s) subscribed for the TDs and the TDs. In addition, the TSN AF may prepare the mapping between the UEs/DS-TT ports and the TDs. At <NUM>, the TSN AF may forward TDs information to the PCF, which may subsequently forward the TDs information to the SMF. In particular, the TSN AF may provide the mapping information to the <NUM> network via exposure framework to the PCF. The PCF may then forward the mapping information to the SMF, and the SMF may store the information. According to certain example embodiments, this exchange may extend the time synchronization exposure framework to let the AF forward the information about the TDs. As further illustrated in <FIG>, at <NUM>, a PDU session may be established between the network elements.

At <NUM>, the SMF may correlate the information received from the TSN AF and the port binding information to track the association of TDs, UEs, and PDU sessions. Further, as illustrated in <FIG>, steps <NUM>, <NUM>, <NUM>, and <NUM> may be similar to steps <NUM>, <NUM>, <NUM>, and <NUM> in <FIG>. Specifically, at <NUM>, during PDU session establishment, the SMF may configure the TDs that the UPF may forward per PDU session or UE. According to certain example embodiments, the SMF may send TDs information indication to the UPF during the configuration of the UPF. In other words, the SMF may send TD information to the UPF. At the end, the SMF may configure the routing at the UPF and, thus, every piece of information that may be useful for packet classification may be considered. In addition, the SMF may forward the TDs information related to certain UE and/or PDU session to the UPF. In certain example embodiments, the TDs information may include triggers to switch the TD to forward to a UE, forwarding rules, or updates in the association between TD(s), UEs, and PDU sessions. According to certain example embodiments, the information exchanged may impact the PFCP between SMF and UPF to include extensions for the new set of information. Additionally, the SMF may be subscribed to mobility events to obtain updates from the access and mobility management function (AMF), and report to the UPF if needed.

At <NUM>, using the information obtained at <NUM>, the UPF may update the local information associating TD(s) and UEs. In particular, the UPF/NW-TT may determine (e.g., based on mobility events, location, etc.) the TD to forward to a PDU session. According to certain example embodiments, in this step, the UPF may maintain a local table with the association between TDs numbers and PDU sessions. At <NUM>, the NW-TT may receive (g)PTP packets associated with TD #<NUM>, TD #<NUM>, and TD #<NUM>. Further, at <NUM>, the UPF/NW-TT may inspect the (g)PTP packets, and forward the (g)PTP packet associated with a corresponding TD (e.g., TD #<NUM>) the UE needs. In particular, when a (g)PTP packet is received in the UPF/NW-TT, the TD number may be read, and the packet may be forwarded to the matching PDU sessions the UPF has configured.

Certain example embodiments may provide a further solution to configure the TD (or working clock domain) determination at the UPF. For instance, this solution may have a similar signaling flow as illustrated in <FIG>. However, the mapping information may be available at the NW-TT, which provides this to the SMF via UPF or via AF. The steps after <NUM> may be the same. Further, in certain example embodiments, the SMF may eventually configure the UPF with that information. In addition, based on the configuration from the SMF, UPF may be able to determine which Ethernet frames are to be mapped to which PDU session based on their Ethernet multicast destination address and/or time domain number (e.g., time domain information (TDs)). According to certain example embodiments, when the SMF sends the N4 rules to the UPF (e.g., PDR, FAR, QER), the classification of the traffic may include specific filters for the (g)PTP packets, or the use of the multicast address as the filter of the PDRs. Thus, if the SMF is responsible for completely managing this process in the UPF, the SMF may send the specific dedicated forwarding rules per UE to the UPF, and update the information when it is determined due to events triggered by the AMF or because of a notification from the UPF.

<FIG> illustrates a flow diagram of a method, according to certain example embodiments. In certain example embodiments, the flow diagram of <FIG> may be performed by a telecommunications network entity or network node in a 3GPP system, such as LTE or <NUM>-NR. For instance, in certain example embodiments, the method of <FIG> may be performed by a session management function, for instance similar to apparatus <NUM> illustrated in <FIG>.

According to certain example embodiments, the method of <FIG> may include, at <NUM>, receiving time domain information at a session management function during a protocol data unit (PDU) procedure. The method may also include, at <NUM>, forwarding the time domain information to a user plane function for the PDU procedure. The method may further include, at <NUM>, configuring the user plane function according to the time domain information to enable determination of a correct mapping between the time domain information and a user equipment or a PDU session.

According to certain example embodiments, the forwarding may include forwarding configuration including one or more extensions for a new set of time domain information. According to other example embodiments, the time domain information may include an associated working clock domain number, a trigger to switch a time domain to forward to the user equipment or the PDU session, a forwarding rule, a packet filter, or an update in an association between the time domain, the user equipment, and the PDU session. In certain example embodiments, the method may also include subscribing to a mobility event of the user equipment to obtain an update of the mobility event. In other example embodiments, the method may further include reporting the mobility events to the user plane function.

<FIG> illustrates a flow diagram of another method, according to certain example embodiments. In certain example embodiments, the flow diagram of <FIG> may be performed by a telecommunications network entity or network node in a 3GPP system, such as LTE or <NUM>-NR. For instance, in certain example embodiments, the method of <FIG> may be performed by a session management function, for instance similar to apparatus <NUM> illustrated in <FIG>.

According to certain example embodiments, the method of <FIG> may include, at <NUM>, receiving time domain information and mapping information. The method may also include, at <NUM>, correlating the time domain information and the mapping information and a protocol data unit (PDU) session procedure. Further, at <NUM>, the method may include configuring a user plane function according to the time domain information or the mapping information to enable determination of a correct mapping between the time domain information and a user equipment or a PDU session.

According to certain example embodiments, the mapping information may include a mapping between the time domain information and a user equipment subscribed to the time domain information. In certain example embodiments, the mapping information may be received via non-access stratum signaling from a user equipment, or via exposure frame from at time sensitive networking application function or an application function, or derived from an outcome of a best master clock algorithm. In other example embodiments, the configuring may be performed during the PDU session procedure. In some example embodiments, the time domain information may include an associated working clock domain number, a trigger to switch a time domain to forward to the user equipment or PDU session, a forwarding rule, a packet filter, or an update in an association between the time domain, the user equipment, and the PDU session. According to certain example embodiments, the method may also include subscribing to a mobility event of the user equipment to obtain an update of the mobility event. According to further example embodiments, the method may include reporting the mobility event to the user plane function.

<FIG> illustrates a flow diagram of another method, according to certain example embodiments. In an example embodiment, the method of <FIG> may be performed by a telecommunications network entity or network node in a 3GPP system, such as LTE or <NUM>-NR. For instance, in certain example embodiments, the method of <FIG> may be performed by a UPF similar to apparatus <NUM> illustrated in <FIG>.

According to certain example embodiments, the method may include, at <NUM>, receiving time domain information for a protocol data unit (PDU) session. The method may also include, at <NUM>, updating local information associating the time domain information and a user equipment or the PDU session based on one or more parameters related to the user equipment. The method may further include, at <NUM>, receiving a time protocol packet. In addition, at <NUM>, the method may include determining whether to send the time protocol packet to the user equipment for a given PDU session based on the received time domain information. Further, at <NUM>, the method may include, based on the determination, sending the time protocol packet to the user equipment for the given PDU session or performing other forwarding action to the time protocol packet. For instance, in certain example embodiments, the UPF may keep the packet, drop it, or replace it.

According to certain example embodiments, the one or more parameters may include information relating to one or more of a mobility event, a location, or a traffic inspection. According to other example embodiments, the time protocol packet may be a generic precision time protocol packet or a precision time protocol packet. According to further example embodiments, the time protocol packet may include time information related to a clock domain number. In certain example embodiments, the updating may include maintaining a local table with an association between the time domain information and the PDU session.

According to certain example embodiments, the method may include, at <NUM>, receiving time domain information or mapping information for a protocol data unit (PDU) session. The method may also include at <NUM>, updating local information that associates the time domain information or the mapping information and the user equipment based on one or more parameters related to the user equipment. The method may further include, at <NUM>, receiving a time protocol packet. At <NUM>, the method may include determining whether to send the time protocol packet to the user equipment for a given PDU session based on the received time domain information or the mapping information. In addition, at <NUM>, the method may include based on the determination, sending the time protocol packet to the user equipment for the given PDU session or performing other forwarding action to the time protocol packet. For instance, in certain example embodiments, the UPF may keep the packet, drop it, or replace it.

According to certain example embodiments, the mapping information may include a mapping between the time domain information and a user equipment subscribed to the time domain information. In certain example embodiments, the mapping information may be received from a user equipment, or via an exposure framework from a time sensitive networking application function or an application function, or derived from an outcome of a best master clock algorithm. In some example embodiments, the updating may include maintaining a local table with the association between the time domain information and the PDU session. In other example embodiments, the one or more parameters may include one or more of a mobility event, a location, or a traffic inspection. According to certain example embodiments, the time protocol packet may be a generic precision time protocol packet or a precision time protocol packet.

<FIG> illustrates an apparatus <NUM> according to certain example embodiments. In certain example embodiments, apparatus <NUM> may be a node or element in a communications network or associated with such a network. For instance, in certain example embodiments, apparatus <NUM> may be a UE, mobile equipment (ME), mobile station, mobile device, stationary device, IoT device, or other device. As described herein, UE may alternatively be referred to as, for example, a mobile station, mobile equipment, mobile unit, mobile device, user device, subscriber station, wireless terminal, tablet, smart phone, IoT device, sensor or NB-IoT device, or the like. In other example embodiments, apparatus <NUM> may be implemented in, for instance, a wireless handheld device, a wireless plug-in accessory, or the like.

In some example embodiments, apparatus <NUM> may be configured to operate using one or more radio access technologies, such as GSM, LTE, LTE-A, NR, <NUM>, WLAN, WiFi, NB-IoT, Bluetooth, NFC, MulteFire, and/or any other radio access technologies.

While a single processor <NUM> is shown in <FIG>, multiple processors may be utilized according to other example embodiments. For example, it should be understood that, in certain example embodiments, apparatus <NUM> may include two or more processors that may form a multiprocessor system (e.g., in this case processor <NUM> may represent a multiprocessor) that may support multiprocessing. According to certain example embodiments, the multiprocessor system may be tightly coupled or loosely coupled (e.g., to form a computer cluster).

Processor <NUM> may perform functions associated with the operation of apparatus <NUM> including, as some examples, precoding of antenna gain/phase parameters, encoding and decoding of individual bits forming a communication message, formatting of information, and overall control of the apparatus <NUM>, including processes illustrated in <FIG>.

In certain example embodiments, apparatus <NUM> may further include or be coupled to (internal or external) a drive or port that is configured to accept and read an external computer readable storage medium, such as an optical disc, USB drive, flash drive, or any other storage medium. For example, the external computer readable storage medium may store a computer program or software for execution by processor <NUM> and/or apparatus <NUM> to perform any of the methods illustrated in <FIG>.

In some example embodiments, apparatus <NUM> may also include or be coupled to one or more antennas <NUM> for receiving a downlink signal and for transmitting via an uplink from apparatus <NUM>.

In other example embodiments, transceiver <NUM> may be capable of transmitting and receiving signals or data directly. Additionally or alternatively, in some example embodiments, apparatus <NUM> may include an input and/or output device (I/O device). In certain example embodiments, apparatus <NUM> may further include a user interface, such as a graphical user interface or touchscreen.

In certain example embodiments, memory <NUM> stores software modules that provide functionality when executed by processor <NUM>. According to certain example embodiments, apparatus <NUM> may optionally be configured to communicate with apparatus <NUM> via a wireless or wired communications link <NUM> according to any radio access technology, such as NR.

According to certain example embodiments, processor <NUM> and memory <NUM> may be included in or may form a part of processing circuitry or control circuitry. In addition, in some example embodiments, transceiver <NUM> may be included in or may form a part of transceiving circuitry.

<FIG> illustrates an apparatus <NUM> according to certain example embodiments. In certain example embodiments, the apparatus <NUM> may be a network element, node, host, or server in a communication network or serving such a network. For example, apparatus <NUM> may be a network element including, for example, an AMF of 5GC, a UPF, or a SMF. In other example embodiments, apparatus <NUM> may be a base station, a Node B, an evolved Node B (eNB), <NUM> Node B or access point, next generation Node B (NG-NB or gNB), and/or WLAN access point, associated with a radio access network (RAN), such as an LTE network, <NUM> or NR.

For example, processor <NUM> may include one or more of general-purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs), field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), and processors based on a multi-core processor architecture, as examples. While a single processor <NUM> is shown in <FIG>, multiple processors may be utilized according to other example embodiments. For example, it should be understood that, in certain example embodiments, apparatus <NUM> may include two or more processors that may form a multiprocessor system (e.g., in this case processor <NUM> may represent a multiprocessor) that may support multiprocessing. In certain example embodiments, the multiprocessor system may be tightly coupled or loosely coupled (e.g., to form a computer cluster.

According to certain example embodiments, processor <NUM> may perform functions associated with the operation of apparatus <NUM>, which may include, for example, precoding of antenna gain/phase parameters, encoding and decoding of individual bits forming a communication message, formatting of information, and overall control of the apparatus <NUM>, including processes illustrated in <FIG>.

In certain example embodiments, apparatus <NUM> may further include or be coupled to (internal or external) a drive or port that is configured to accept and read an external computer readable storage medium, such as an optical disc, USB drive, flash drive, or any other storage medium. For example, the external computer readable storage medium may store a computer program or software for execution by processor <NUM> and/or apparatus <NUM> to perform the methods illustrated in <FIG>.

In certain example embodiments, apparatus <NUM> may also include or be coupled to one or more antennas <NUM> for transmitting and receiving signals and/or data to and from apparatus <NUM>. Apparatus <NUM> may further include or be coupled to a transceiver <NUM> configured to transmit and receive information. The transceiver <NUM> may include, for example, a plurality of radio interfaces that may be coupled to the antenna(s) <NUM>. The radio interfaces may correspond to a plurality of radio access technologies including one or more of GSM, NB-IoT, LTE, <NUM>, WLAN, Bluetooth, BT-LE, NFC, radio frequency identifier (RFID), ultrawideband (UWB), MulteFire, and the like. The radio interface may include components, such as filters, converters (for example, digital-to-analog converters and the like), mappers, a Fast Fourier Transform (FFT) module, and the like, to generate symbols for a transmission via one or more downlinks and to receive symbols (for example, via an uplink).

In other example embodiments, transceiver <NUM> may be capable of transmitting and receiving signals or data directly. Additionally or alternatively, in some example embodiments, apparatus <NUM> may include an input and/or output device (I/O device).

In certain example embodiments, memory <NUM> may store software modules that provide functionality when executed by processor <NUM>.

According to some example embodiments, processor <NUM> and memory <NUM> may be included in or may form a part of processing circuitry or control circuitry. In addition, in some example embodiments, transceiver <NUM> may be included in or may form a part of transceiving circuitry.

As used herein, the term "circuitry" may refer to hardware-only circuitry implementations (e.g., analog and/or digital circuitry), combinations of hardware circuits and software, combinations of analog and/or digital hardware circuits with software/firmware, any portions of hardware processor(s) with software (including digital signal processors) that work together to cause an apparatus (e.g., apparatus <NUM> and <NUM>) to perform various functions, and/or hardware circuit(s) and/or processor(s), or portions thereof, that use software for operation but where the software may not be present when it is not needed for operation.

As introduced above, in certain example embodiments, apparatus <NUM> may be a network element, node, host, or server in a communication network or serving such a network. For example, apparatus <NUM> may be a AMF, SMF, satellite, base station, a Node B, an evolved Node B (eNB), <NUM> Node B or access point, next generation Node B (NG-NB or gNB), and/or WLAN access point, associated with a radio access network (RAN), such as an LTE network, <NUM> or NR. According to certain example embodiments, apparatus <NUM> may be controlled by memory <NUM> and processor <NUM> to perform the functions associated with any of the embodiments described herein.

For instance, in certain example embodiments, apparatus <NUM> may be controlled by memory <NUM> and processor <NUM> to receive time domain information at a session management function during a protocol data unit (PDU) session procedure. Apparatus <NUM> may also be controlled by memory <NUM> and processor <NUM> to forward the time domain information to a user plane function for the PDU session procedure. Apparatus <NUM> may further be controlled by memory <NUM> and processor <NUM> to configure the user plane function according to the time domain information to enable determination of a correct mapping between the time domain information and a user equipment or a PDU session.

In other example embodiments, apparatus <NUM> may be controlled by memory <NUM> and processor <NUM> to receive time domain information and mapping information. Apparatus <NUM> may also be controlled by memory <NUM> and processor <NUM> to correlate the time domain information and the mapping information and a protocol data unit (PDU) session procedure. In addition, apparatus <NUM> may be controlled by memory <NUM> and processor <NUM> to configure a user plane function according to the time domain information or the mapping information to enable determination of a correct mapping between the time domain information and a user equipment or a PDU session.

In other example embodiments, apparatus <NUM> may be controlled by memory <NUM> and processor <NUM> to receive time domain information for a protocol data unit (PDU) session. Apparatus <NUM> may also be controlled by memory <NUM> and processor <NUM> to update local information associating the time domain information and a user equipment or the PDU session based on a combination of parameters related to the user equipment. Apparatus <NUM> may further be controlled by memory <NUM> and processor <NUM> to receive a time protocol packet. In addition, apparatus <NUM> may be controlled by memory <NUM> and processor <NUM> to determine whether to send the time protocol packet to the user equipment for a given PDU session based on the received time domain information. Further, apparatus <NUM> may be controlled by memory <NUM> and processor <NUM> to, based on the determination, send the time protocol packet to the user equipment for the given PDU session or perform other forwarding action to the time protocol packet.

In other example embodiments, apparatus <NUM> may be controlled by memory <NUM> and processor <NUM> to receive time domain information or mapping information for a protocol data unit (PDU) session. Apparatus <NUM> may also be controlled by memory <NUM> and processor <NUM> to update local information that associates the time domain information or the mapping information and a user equipment based on one or more parameters related to the user equipment. Apparatus <NUM> may further be controlled by memory <NUM> and processor <NUM> to receive a time protocol packet. In addition, apparatus <NUM> may be controlled by memory <NUM> and processor <NUM> to determine whether to send the time protocol packet to the user equipment for a given PDU session based on the received time domain information or the mapping information. Further, apparatus <NUM> may be controlled by memory <NUM> and processor <NUM> to, based on the determination, send the time protocol packet to the user equipment for the given PDU session or perform other forwarding action to the time protocol packet.

Further example embodiments may provide means for performing any of the functions, steps, or procedures described herein. For example one example embodiment may be directed to an apparatus that includes means for receiving time domain information at a session management function during a protocol data unit (PDU) session procedure. The apparatus may also include means for forwarding the time domain information to a user plane function for the PDU session procedure. The apparatus may further include means for configuring the user plane function according to the time domain information to enable determination of a correct mapping between the time domain information and a user equipment.

Other example embodiments may be directed to an apparatus that includes means for receiving time domain information and mapping information. The apparatus may also include means for storing the time domain information and mapping information. The apparatus may further include means for correlating the time domain information and the mapping information. In addition, the apparatus may include means for configuring a user plane function according to the time domain information or the mapping information to enable determination of a correct mapping between the time domain information and a user equipment.

Other example embodiments may be directed to a further apparatus that includes means for receiving time domain information for a protocol data unit (PDU) session. The apparatus may also include means for updating local information associating the time domain information and a user equipment based on a combination of parameters related to the user equipment. The apparatus may further include means for receiving a time protocol packet. In addition, the apparatus may include means for determining whether the time protocol packet needs to be sent to the user equipment for a given PDU session based on the received time domain information. The apparatus may also include means for, based on the determination, sending the time protocol packet to the user equipment for the given PDU session or performing other forwarding action to the time protocol packet.

Other example embodiments may be directed to a further apparatus that includes means for receiving time domain information or mapping information for a protocol data unit (PDU) session. The apparatus may also include means for updating local information that associates the time domain information or the mapping information and a user equipment based on a combination of parameters related to the user equipment. The apparatus may further include means for receiving a time protocol packet. In addition, the apparatus may include means for determining whether the time protocol packet needs to be sent to the user equipment for a given PDU session based on the received time domain information or the mapping information. The apparatus may also include means for, based on the determination, sending the time protocol packet to the user equipment for the given PDU session or performing other forwarding action to the time protocol packet.

Certain example embodiments described herein provide several technical improvements, enhancements, and /or advantages. In some example embodiments, it may be possible to introduce TDs of interest for the UE as part of the PDU session management to optimize time information distribution to UEs. Using the available TDs, the 5GC may update the user plane configuration to provide the UE only with the synchronization messages for the TD(s) that are needed by the UE. According to certain example embodiments, it may be possible for the UPF to dynamically determine the TD(s) for which synchronization messages need to be forwarded to a UE based on a combination of parameters related to the UE including, for example, mobility events, location, and traffic inspection.

A computer program product may include one or more computer-executable components which, when the program is run, are configured to carry out some example embodiments. The one or more computer-executable components may be at least one software code or portions of it. Modifications and configurations required for implementing functionality of an example embodiment may be performed as routine(s), which may be implemented as added or updated software routine(s). Software routine(s) may be downloaded into the apparatus.

As an example, software or a computer program code or portions of it may be in a source code form, object code form, or in some intermediate form, and it may be stored in some sort of carrier, distribution medium, or computer readable medium, which may be any entity or device capable of carrying the program. Such carriers may include a record medium, computer memory, read-only memory, photoelectrical and/or electrical carrier signal, telecommunications signal, and software distribution package, for example. The computer readable medium or computer readable storage medium may be a non-transitory medium.

In other example embodiments, the functionality may be performed by hardware or circuitry included in an apparatus (e.g., apparatus <NUM> or apparatus <NUM>), for example through the use of an application specific integrated circuit (ASIC), a programmable gate array (PGA), a field programmable gate array (FPGA), or any other combination of hardware and software. In yet another example embodiment, the functionality may be implemented as a signal, a non-tangible means that can be carried by an electromagnetic signal downloaded from the Internet or other network.

According to certain example embodiments, an apparatus, such as a node, device, or a corresponding component, may be configured as circuitry, a computer or a microprocessor, such as single-chip computer element, or as a chipset, including at least a memory for providing storage capacity used for arithmetic operation and an operation processor for executing the arithmetic operation.

Claim 1:
A method, comprising:
receiving time domain, TD, information for a protocol data unit, PDU, session;
updating local information associating the time domain information and a user equipment,
receiving a plurality of time protocol packets, wherein a respective time protocol
packet is a generic precision time protocol, gPTP, message ;
based on the updated local information, determining, by a user plane function, UDF, whether to send a respective time protocol packet of the plurality of time protocol packets to the user equipment for a given PDU session based on the received time domain information, based on the UE changing a serving cell when a signal is stronger in a target cell than in a source cell, wherein the UPF inspects the plurality of time protocol packets based on a TD number for forwarding the respective time protocol packet to a matching PDU session the UPF has configured; and
based on the determination, forwarding the respective time protocol packet of the plurality of time protocol packets to the user equipment for the matching PDU session.