MPS handling for SMS over nas

Abstract

Methods and apparatus are provided for supporting Multimedia priority services (MPS) for SMS over NAS. The method is performed by an Access and Mobility management Function (AMF) or an SMS function (SMSF) used for the UE, and comprises obtaining for the UE subscription data comprising MPS for short message indication and setting a message priority header based on the obtained MPS for short message indication when the MPS for short message indication indicates MPS is to be applied for short message service in messages transmitted between the AMF and the SMSF associated with the UE.

Description

MPS handling for SMS over NASRelated ApplicationsThis application claims the benefit of provisional patent application serial number 63 / 620368, filed on 1 / 12 / 2024, the disclosure of which is hereby incorporated herein by reference in its entirety.Technical Field

[0001] The present disclosure relates to a cellular communications system and, more particularly, priority handling and short message service.Background

[0002] Multimedia Priority Service (MPS) is specified by 3GPP to give priority handling during service for certain users as described in 3GPP TS 23.501 clause 5.16.5 and 5.22.The SMS / message service is also supported by 3GPP via NAS as specified in TS 23.501 clause 4.4.2(and over IP / IMS in other TSs).As currently specified, short message service (SMS) is not part of the services covered by MPS. As such, a solution to provide MPS treatment for SMS service over NAS is described herein.Summary

[0003] Certain aspects of the present disclosure and their embodiments may provide solutions to the aforementioned or other challenges.

[0004] According to some embodiments, a method performed by an Access and Mobility management Function (AMF) is provided. The method comprises the step of obtaining subscription data from a subscription data management (e.g., UDM) for a User Equipment (UE), the subscription data comprises Multimedia Priority Services (MPS) for short message indication and may include a priority level. The method comprises also the step of setting a message priority header based on the obtained MPS for short message indication when the MPS for short message indication indicates MPS is to be applied for short message service in messages transmitted to a short message service function (SMSF) associated with the UE.

[0005] For example, when the priority level is included, the method comprises the step of using the priority level when setting the message priority header.

[0006] According to some aspects, the method further comprises the step of receiving a first message from the SMSF for requesting availability of the LIE for Short Message Service (SMS) and sending a paging message to a Radio Access node serving the LIE in idle mode and including in the paging message a paging priority determined based on the obtained MPS for short message indication and optionally the priority level.

[0007] According to some embodiment, a method performed by a Short Message Service Function (SMSF) handling short message service for a User Equipment (UE) is provided, the method comprises the step of obtaining for the UE, subscription data comprising Multimedia Priority Services (MPS) for short message indication and optionally a priority level and setting a message priority header based on the obtained MPS for short message indication when the MPS for short message indication indicates MPS is to be applied for short message service in messages transmitted to an Access & Mobility Management serving the UE.

[0008] For example, the method further comprises upon the SMSF transmitting a message to a messaging gateway ( for MO initiated SMS), setting a message priority header based on the obtained MPS for short message indication when the MPS for short message indication indicates MPS is to be applied for short message service.

[0009] For example, the method further comprises the step of using the priority level if received when setting the message priority level.

[0010] According to some embodiments, a network node is configured to perform the methods of any of the embodiments described herein for the SMSF (or equivalent) and / or the access and mobility management function (or equivalent).

[0011] According to some embodiments, a network node comprising one or more processors and memory comprising instructions which when executed by the one or more processors enable the network node to perform the methods of any of the embodiments described herein for the SMSF (or equivalent) and / or the access and mobility management function (or equivalent).

[0012] According to some embodiments a computer readable memory is provided, where the computer readable memory comprises instructions which when executed by one or more processors of one or more servers configures the one or more servers toperform any of the embodiments described herein for the SMSF (or equivalent) and / or the access and mobility management function (or equivalent).Brief Description of the Drawings

[0013] The accompanying drawing figures incorporated in and forming a part of this specification illustrate several aspects of the disclosure, and together with the description serve to explain the principles of the disclosure.

[0014] Figure 1 illustrates one example of a cellular communications system 100 in which embodiments of the present disclosure may be implemented;

[0015] Figures 2 and 3 illustrate example embodiments of the cellular communication system of Figure 1;

[0016] Figure 4 illustrates an architecture based on Figure 3 with focus on network functions involved in short messaging service;

[0017] Figures 5, 6 and 7 illustrate embodiments of the present disclosure for registration for SMS, MO SMS and MT SMS delivery in accordance with example embodiments;

[0018] Figure 8 illustrate a flow chart for AMF in accordance with some embodiments;

[0019] Figure 9 illustrate a flow chart for SMSF in accordance with other embodiments;

[0020] Figures 10, 11, and 12 are schematic block diagrams of example embodiments of a network node.Detailed Description

[0021] The embodiments set forth below represent information to enable those skilled in the art to practice the embodiments and illustrate the best mode of practicing the embodiments. Upon reading the following description in light of the accompanying drawing figures, those skilled in the art will understand the concepts of the disclosure and will recognize applications of these concepts not particularly addressed herein. It should be understood that these concepts and applications fall within the scope of the disclosure.

[0022] Some of the embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. Other embodiments, however, arecontained within the scope of the subject matter disclosed herein, the disclosed subject matter should not be construed as limited to only the embodiments set forth herein; rather, these embodiments are provided by way of example to convey the scope of the subject matter to those skilled in the art.

[0023] Generally, all terms used herein are to be interpreted according to their ordinary meaning in the relevant technical field, unless a different meaning is clearly given and / or is implied from the context in which it is used. All references to a / an / the element, apparatus, component, means, step, etc. are to be interpreted openly as referring to at least one instance of the element, apparatus, component, means, step, etc., unless explicitly stated otherwise. The steps of any methods disclosed herein do not have to be performed in the exact order disclosed, unless a step is explicitly described as following or preceding another step and / or where it is implicit that a step must follow or precede another step. Any feature of any of the embodiments disclosed herein may be applied to any other embodiment, wherever appropriate. Likewise, any advantage of any of the embodiments may apply to any other embodiments, and vice versa. Other objectives, features, and advantages of the enclosed embodiments will be apparent from the following description.

[0024] Radio Node: As used herein, a "radio node" is either a radio access node or a wireless communication device.

[0025] Radio Access Node: As used herein, a "radio access node" or "radio network node" or "radio access 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 (5G) 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 low-power base station (e.g., a micro base station, a pico base station, a home eNB, or the like), a relay node, a network node that implements part of the functionality of a base station (e.g., a network node that implements a gNB Central Unit (gNB-CU) or a network node that implements a gNB Distributed Unit (gNB-DU)) or a network node that implements part of the functionality of some other type of radio access node.

[0026] 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. The node can be a server or system of distributed servers. Some examples of a core network node include, e.g., an Access and Mobility Management Function (AMF), a User Plane Function (UPF), a Session Management Function (SMF), an Short message service function (SMSF), an Authentication Server Function (AUSF), a Network Slice Selection Function (NSSF), a Network Exposure Function (NEF), a Network Function (NF) Repository Function (NRF), a Policy Control Function (PCF), a Unified Data Management (UDM), a Network slice Admission Control function (NSACF) or the like. The Core network functions may be virtualized / containerized on a node, server, distributed servers, or implemented as a dedicated function on a dedicated physical node (compute, memory, and network). Other future core network functions in future core networks such as 6G and beyond are also applicable for this invention.

[0027] Communication Device: As used herein, a "communication device" is any type of device that has access to an access network. Some examples of a communication device include, but are not limited to: mobile phone, smart phone, sensor device, meter, vehicle, household appliance, medical appliance, media player, camera, or any type of consumer electronic, for instance, but not limited to, a television, radio, lighting arrangement, tablet computer, laptop, or Personal Computer (PC). The communication device may be a portable, hand-held, computer-comprised, or vehiclemounted mobile device, enabled to communicate voice and / or data via a wireless or wireline connection.

[0028] Wireless Communication Device: One type of communication device is a wireless communication device, which may be any type of wireless device that has access to (i.e., is served by) a wireless network (e.g., a cellular network). Some examples of a wireless communication device include, but are not limited to: a User Equipment device (UE) in a 3GPP network, a Machine Type Communication (MTC) device, and an Internet of Things (loT) device. Such wireless communication devices may be, or may be integrated into, a mobile phone, smart phone, sensor device, meter, vehicle, household appliance, medical appliance, media player, camera, or any type of consumer electronic, for instance, but not limited to, a television, radio, lighting arrangement, tablet computer, laptop, or PC. The wireless communication device maybe a portable, hand-held, computer-comprised, or vehicle-mounted mobile device, enabled to communicate voice and / or data via a wireless connection.

[0029] Network Node: As used herein, a "network node" is any node that is either part of the RAN or the core network of a cellular communications network / system.

[0030] Note that the description given herein focuses on a 3GPP cellular communications system and, as such, 3GPP terminology or terminology similar to 3GPP terminology is oftentimes used. However, the concepts disclosed herein are not limited to a 3GPP system.

[0031] Note that, in the description herein, reference may be made to the term "cell"; however, particularly with respect to 5G NR concepts, beams may be used instead of cells and, as such, it is important to note that the concepts described herein are equally applicable to both cells and beams.

[0032] Figure 1 illustrates one example of a cellular communications system 100 in which embodiments of the present disclosure may be implemented. In the embodiments described herein, the cellular communications system 100 is a 5G system (5GS) including a Next Generation RAN (NG-RAN) and a 5G Core (5GC); however, the present disclosure is not limited thereto. In this example, the RAN includes base stations 102-1 and 102-2, which in the 5GS include NR base stations (gNBs) and optionally next generation eNBs (ng-eNBs) (e.g., LTE RAN nodes connected to the 5GC), controlling corresponding (macro) cells 104-1 and 104-2. The base stations 102- 1 and 102-2 are generally referred to herein collectively as base stations 102 and individually as base station 102. Likewise, the (macro) cells 104-1 and 104-2 are generally referred to herein collectively as (macro) cells 104 and individually as (macro) cell 104. The RAN may also include a number of low power nodes 106-1 through 106-4 controlling corresponding small cells 108-1 through 108-4. The low power nodes 106-1 through 106-4 can be small base stations (such as pico or femto base stations) or RRHs, or the like. Notably, while not illustrated, one or more of the small cells 108-1 through 108-4 may alternatively be provided by the base stations 102. The low power nodes 106-1 through 106-4 are generally referred to herein collectively as low power nodes 106 and individually as low power node 106. Likewise, the small cells 108-1 through 108-4 are generally referred to herein collectively as small cells 108 and individually as small cell 108. The cellular communications system 100 also includes a core network110, which in the 5G System (5GS) is referred to as the 5GC. The base stations 102 (and optionally the low power nodes 106) are connected to the core network 110.

[0033] The base stations 102 and the low power nodes 106 provide service to wireless communication devices 112-1 through 112-5 in the corresponding cells 104 and 108. The wireless communication devices 112-1 through 112-5 are generally referred to herein collectively as wireless communication devices 112 and individually as wireless communication device 112. In the following description, the wireless communication devices 112 are oftentimes UEs and as such sometimes referred to herein as UEs 112, but the present disclosure is not limited thereto.

[0034] Figure 2 illustrates a wireless communication system represented as a 5G network architecture composed of core Network Functions (NFs), where interaction between any two NFs is represented by a point-to-point reference poinf / interface. Figure 2 can be viewed as one particular implementation of the system 100 of Figure 1. The embodiments in the reminder of these document are described within the context of 5G network architecture using the 5G terminology, but the embodiments are also applicable to other systems / networks using SMS and MPS. Example of those systems / networks may be 6G systems / networks and beyond.

[0035] Seen from the access side the 5G network architecture shown in Figure 2 comprises a plurality of UEs 112 connected to either a RAN 102 or an Access Network (AN) as well as an AMF 200. Typically, the R(AN) 102 comprises base stations, e.g. such as eNBs or gNBs or similar. Seen from the core network side, the 5GC NFs shown in Figure 2 include a NSSF 202, an AUSF 204, a UDM 206, the AMF 200, a SMSF 220, a SMF 208, a PCF 210, and an Application Function (AF) 212.

[0036] Reference point representations of the 5G 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 112 and AMF 200. The reference points for connecting between the AN 102 and AMF 200 and between the AN 102 and UPF 214 are defined as N2 and N3, respectively. There is a reference point, Nil, between the AMF 200 and SMF 208, which implies that the SMF 208 is at least partly controlled by the AMF 200. N4 is used by the SMF 208 and UPF 214 so that the UPF 214 can be set using the control signal generated by the SMF 208, and the UPF 214 can report its state to the SMF 208. The SMSF 220 communicates with the AMF 200 over the N20 reference point, and with UDM 206 over the N21 reference point, and AMF 200 communicateswith UDM 206 over the N8 reference point as illustrated in Figure 2. N9 is the reference point for the connection between different UPFs 214, and N14 is the reference point connecting between different AMFs 200, respectively. N15 and N7 are defined since the PCF 210 applies policy to the AMF 200 and SMF 208, respectively. N12 is required for the AMF 200 to perform authentication of the UE 112. N8 and N10 are defined because the subscription data of the UE 112 is required for the AMF 200 and SMF 208. N80 is the reference point between AMF 200 and NSACF 207 and N81 reference point is between SMF 208 and NSACF 207.

[0037] The 5GC network aims at separating UP and CP. The UP carries user traffic while the CP carries signaling in the network. In Figure 2, the UPF 214 is in the UP and all other NFs, i.e., the AMF 200, SMF 208, PCF 210, AF 212, NSSF 202, AUSF 204, and UDM 206, are in the CP. Separating the UP and CP guarantees each plane resource to be scaled independently. It also allows UPFs to be deployed separately from CP 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.

[0038] The 5G core network architecture is composed of modularized functions. For example, the AMF 200, SMF 208 and for example SMSF 220 are independent functions in the CP. Separated AMF 200 and SMF 208 allow independent evolution and scaling. Other CP functions like the PCF 210 and AUSF 204 can be separated as shown in Figure 2. Modularized function design enables the 5GC network to support various services flexibly.

[0039] Each NF interacts with another NF directly. It is possible to use intermediate functions to route messages from one NF to another NF. In the CP, a set of interactions between two NFs is defined as service so that its reuse is possible. This service enables support for modularity. The UP supports interactions such as forwarding operations between different UPFs.

[0040] Figure 3 illustrates a 5G network architecture using service-based interfaces between the NFs in the CP, instead of the point-to-point reference points / interfaces used in the 5G network architecture of Figure 2. The description of Figure 2 and 3 may be applicable to future generation of 3GPP architecture with similar or equivalent functions and services and the embodiments herein equally apply to those systems. The NFs described above with reference to Figure 2 correspond to the NFs shown inFigure 3. 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 Figure 3 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 200 and Nsmf for the service based interface of the SMF 208, Nsmsf for service based interface exposing services of SMSF 220, etc. Any NFs depicted in Figure 2 can interact with the NEF 216 and / or NRF 218 of Figure 3 as necessary, though not explicitly indicated in Figure 2.

[0041] Some properties of the NFs shown in Figures 2 and 3 may be described in the following manner. The AMF 200 provides UE-based authentication, authorization, mobility management, etc. A LIE 112 even using multiple access technologies is basically connected to a single AMF 200 because the AMF 200 is independent of the access technologies. The SMSF220 is responsible for SMS management subscription data checking and conducting SMS delivery accordingly, relaying the Short Message from the UE toward SMS-GMSC / IWMSC / SMS-Router (see Figure 4), relaying the Short message from SMS-GMSC / IWMSC / SMS-Router toward the UE (see Figure 4), SMS charging and interacting with AMF 200 and SMS-GMSC for notification that the UE is unavailable for SMS transfer. The SMF 208 is responsible for session management and allocates Internet Protocol (IP) addresses to UEs. It also selects and controls the UPF 214 for data transfer. If a UE 112 has multiple sessions, different SMFs 208 may be allocated to each session to manage them individually and possibly provide different functionalities per session. The AUSF 204 supports authentication function for UEs or similar and thus stores data for authentication of UEs or similar while the UDM 206 stores subscription data of the UE 112. Many NFs including AMF 200, SMSF 220, SMF 208 communicate with UDM 206 to obtain subscription data and / or notification of UE availability for reachability or SMS availability. The Data Network (DN), not part of the 5GC network, provides Internet access or operator services and similar.

[0042] An NF may be implemented either as a network element on a dedicated hardware, as a software instance running on a dedicated hardware, or as a virtualized function instantiated on an appropriate platform, e.g., a cloud infrastructure.

[0043] As stated in the introduction, there currently exist certain challenges for support of roaming for on-demand network slice(s) (S-NSSAI).

[0044] Certain aspects of the present disclosure and their embodiments may provide solutions to the aforementioned or other challenges. Embodiments of the solutionsdescribed herein enable support of MPS treatment for SMS over NAS for UE with subscription data that indicates that SMS with MPS handling is included i.e., subscription in the UDM and / or on the IISIM is used for priority treatment related to SMS over NAS. The embodiments are described using 5G core network functions as an example, involving SMSF 220, AMF 200 and UDM 206. However, the solution can apply to SMS over NAS in 4G network (Evolve Packet Core), or 6G network or beyond. SMS over NAS involves sending the SMS in a NAS message instead of messaging over IP sent over the user plane.

[0045] Figure 5 illustrates a Registration procedure for SMS over NAS in accordance with example embodiments.The procedure is based on clause 4.13.3.1 of TS 23.502 as illustrated in Figure 5.

[0046] Step 1: The MPS-subscribed UE transmits a registration request to register for SMS service in an RRC message to an AMF via an NG-RAN (not shown). The UE indicates an appropriate Establishment cause such as for e.g., MPS or MPS for messaging or MPS for SMS in the RRC message.

[0047] This step is similar to steps 1-3 in figure 4.2.2.2.2-1 of TS 23.502 which covers Establishment cause with MPS already. However, in TS 23.502, the MPS treatment does not apply to SMS over NAS related procedure.

[0048] Step 2. Comprises step 4 to 14 of the Registration procedure described in Figure 4.2.2.2.2-1 of TS 23.502 incorporated by reference. However, the AMF 200 receives additional indication for MPS for SMS / messaging from UDM 206 as part of the subscription data.

[0049] For example, the UE subscription data contains addition parameter indicating MPS treatment for message as part of the MPS subscription. This parameter is provided to related NFs involved in SMS over NAS (i.e. AMF 200 and SMSF 220). Table 1 illustrates examples of setting of MPS related subscription data parameters to indicate MPS for SMS / messaging. The new indication is illustrated as MPS for message in the second column.

[0050] Furthermore, the subscription data may further indicate a priority level to be applied when MPS for message is set, for example priority level 1 may indicate higher priority than priority level 2.

[0051] Steps 3 and 4 are similar to steps 3 and 4 of TS 23.502 Figure 4.13.3.1-1 (incorporated by reference). However, the AMF 200 may use the subscription data to select an SMSF 220 that supports priority handling if the subscription indicates MPS for messaging is set.

[0052] Step 5. The AMF 200 invokes Nsmsf_SMService_Activate service operation from the SMSF 220. The invocation includes AMF address, Access Type, RAT Type, Trace Requirements, GPSI (if available) and SUPI. The AMF 200 uses the SMSF Information derived from step 3. The AMF 200 includes a Message Priority header to indicate priority information based on MPS for message indication received in step 2 from the UDM 206. It may also set the Message priority header based on the MPS priority level. The AMF 200 may also provide the MPS for message indication as part of the Nsmsf_SMService_Active Request service operation.

[0053] Step 7a. following UDM discovery at step 6, if the UE context for the current Access Type already exists in the SMSF 220, the SMSF 220 shall replace the old AMF address with the new AMF address. Otherwise, the SMSF 220 considers this a Registration request from a new Access Type and the SMSF 220 registers with the UDM 206 using Nudm_UECM_Registration with Access Type. As a result, the UDM stores the following information: SUPI, SMSF identity, SMSF address, Access Type(s) in UE Context in SMSF data. The UDM may further store SMSF Information in UDR by Nudr_DM_Update (SUPI, Subscription Data, UE Context in SMSF data).

[0054] If the Nsmsf_SMService_Activate request contains two Access Types and one of them is already registered in the SMSF 220, the SMSF 220 shall replace the old AMFaddress with the new AMF address for that Access Type. The SMSF 220 shall then register the other Access Type with the UDM 206 using Nudm_UECM_Registration request. This step is similar to step 7a of TS 23.502 Figure 4.13.3.1-1.

[0055] Steps 7b-7c, also similar to steps 7b-7c of TS 23.502 Figure 4.13.3.1-1, i.e, the SMSF 220 retrieves SMS Management Subscription data (e.g. SMS teleservice, SMS barring list) using Nudm_SDM_Get and this requires that UDM may get this information from UDR by Nudr_DM_Query (SUPI, Subscription Data, SMS Management Subscription data). After a successful response is received, the SMSF 220 subscribes to be notified using Nudm_SDM_Subscribe when the SMS Management Subscription data is modified and UDM may subscribe to notifications from UDR by Nudr_DM_Subscribe.The SMSF 220 also creates a UE context to store the SMS subscription information and the AMF address that is serving this UE.7b-7c. However, for MPS treatment for SMS, the SMSF 220 may also receive the additional MPS for message indication and optional MPS priority level from the UDM 206 as part of the SMS Management Subscription data.

[0056] Steps 8 and 9 are similar to steps 8 and 9 of TS 23.502 Figure 4.13.3.1-1. The SMSF 220 may in addition include priority handling in Message priority header in the response to the AMF 200 in step 8 and which is set based on the subscription data retrieved from the UDM (MPS message information and optional priority level). The AMF 200 may also indicate to the UE in step 9 that MPS treatment will be provided for SMS.

[0057] Figure 6 illustrates MPS treatment of mobile originating SMS procedure in accordance with example embodiments. The procedure illustrated in Figure 6 is based on clause 4.13.3.3 and 4.13.3.5 of TS 23.502 incorporated by reference.

[0058] Step 1. Performed if the UE is idle and needs to send an SMS. More specifically, if the UE under CM-IDLE state is going to send uplink SMS message, then UE and network perform the UE Triggered Service Request procedure firstly as defined in clause 4.2.3.2 of TS 23.502 to establish a NAS signalling connection to AMF 200. The service request is sent to the AMF 200 via an NG-RAN using an RRC message which includes an appropriate Establishment cause value indicating MPS or MPS for messaging or MPS for SMS. If the UE is in CM-connected state, this step is omitted.

[0059] Step 2a. The UE builds the SMS message to be sent as defined in TS 23.040 (incorporated by reference) (i.e. the SMS message consists of CP-DATA / RP- DATA / TPDU / SMS-SUBMIT parts). The SMS message is encapsulated in an NAS messagewith an indication indicating that the NAS message is for SMS transporting. The UE send the NAS message to the AMF 200.

[0060] Step 2b. The AMF 200 forwards the SMS message to the SMSF 220 serving the UE over N20 message by invoking Nsmsf_SMService_UplinkSMS service operation. The AMF 200 includes a Message Priority header to indicate priority information based on MPS for message indication and optionally the priority level available in the UE context (i.e., received during UE registration from UDM and stored as described for Figure 5). The AMF 200 applies the same, i.e., include Message priority header determined based on the UE context in subsequent steps when communicating with the SMSF 220.

[0061] Steps 2c-2d. The SMSF 220 sends an ack response to acknowledge the message received at step 2b and the AMF 200 forwards the ack message in a downlink NAS message to the UE.

[0062] Steps 3-5. The SMSF 220 checks the SMS management subscription data obtained from the UDM 206 (Figure 5). If SMS delivery is allowed, the procedure defined in TS 23.040 or TS 23.540 (incorporated by reference) applies. The SMSF forwards the mobile originating SMS to the SMS-IWMSC or messaging center with a Message priority header set based on the MPS message information and optionally the priority level in order to enable priority handling by the messaging center / SMS-IWMSC. The SMSF 220 receives a Submit report indicating the status of the delivery. The report may include a Message priority header as well to enable the SMSF to apply priority treatment on the received message.

[0063] Steps 6a-6b. The SMSF 220 forwards the submit report to AMF 200 by invoking Namf_Communication_NlN2MessageTransfer service operation. The SMSF 220 includes a Message Priority header to indicate priority information based on MPS for message indication and optionally priority level stored in the UE context in the SMSF (e.g., as obtained from subscription data). The AMF 200 forwards the report to the UE via Downlink NAS transport. The report may be forwarded with priority indication in the message.

[0064] Steps 6c and 6d are similar to steps 6c and 6d of clause 4.13.3.3 of 3GPP TS 23.502.

[0065] Figure 7 illustrates MPS treatment of mobile terminating SMS procedure in accordance with example embodiments. The procedure illustrated in Figure 7 is basedon clause 4.13.3.6, 4.13.3.7 and 4.13.3.8 of TS 23.502 incorporated herein by reference. Some of the steps are enhanced for the MPS treatment for SMS over NAS.

[0066] Steps 1-3. Mobile Terminating (MT) SMS interaction between SC / SMS- GMSC / UDM follow the procedure as defined in 3GPP TS 23.040 or TS 23.540 incorporated herein by reference. If there are two AMFs serving the UE, one is for 3GPP access and another is for non-3GPP access, there are two SMSF addresses stored in UDM / UDR. The UDM 206 shall return both SMSF addresses. In step 2, the UDM 206 indicates to the SMS-GMSC also that the UE is subscribed for MPS for message, similar to information described in table 1 above indicating whether MPS is enabled for messaging / SMS or not and an optional priority level. In step 3, the SMS-GMSC includes a Message Priority header to indicate priority information based on MPS for message indication and optionally priority level received from UDM 206.

[0067] Step 4. The SMSF 220 checks the SMS management subscription data. If SMS delivery is allowed, SMSF invokes Namf_MT_EnableUEReachability service operation to AMF. Further if the subscription data or UE context indicates MPS treatment for SMS, and / or if message received at step 3 indicates a priority handling, the SMSF 220 includes a Message Priority header to the AMF 200 to indicate priority handling. The message priority header is set based on MPS for message indication and optionally the priority level stored in the UE context. If the UE is in CM idle, the AMF 200 pages the UE using the procedure defined in clause 4.2.3.3 of TS 23.502. The AMF 200 also sets a Paging Priority based on the MPS for message information and optionally the priority header. The UE responds to the page with Service Request procedure and the AMF 200 sends a message (Namf_MT_EnableUEReachability Response) to the SMSF to indicate the UE is reachable. The AMF 200 includes a Message Priority header to indicate priority information based on MPS for message indication and optionally a priority level if such information is stored in UE context, when sending message towards the SMSF 220. If the UE is in CM-Connected, the AMF 200 transmits the SMS in a NAS transport message and may include a priority indication in the message priority header for priority handling by the NG-RAN node.

[0068] If the AMF 200 indicates to the SMSF 220 that UE is not reachable, the procedure of the unsuccessful Mobile terminating SMS delivery described in clause 4.13.3.9 of TS 23.502 is performed and the following steps are skipped.

[0069] If the UE access to the AMF 200 via both 3GPP access and non-3GPP access, the AMF determines the Access Type to transfer the MT-SMS based on operator local policy. Note that the subscription data for MPS treatment for SMS is applicable for a UE over an access type. Alternatively, the subscription data may indicate the MPS treatment for SMS per access type, e.g., one for 3GPP access and one for non-3GPP access. For example, the AMF 200 may elect to forward the message over the access type where priority applies in accordance with the subscription per access type if the received message from the SMSF includes a priority indication, else if no priority indication is included in the message from the SMSF 220, the AMF 200 may elect to use the access type for which no priority subscription is received from the UDM 206.

[0070] Step 5a-5b. The SMSF forward the SMS message to be sent as defined in TS 23.040 (i.e. the SMS message consists of CP DATA / RP DATA / TPDU / SMS DELIVER parts) to the AMF 200 by invoking Namf_Communication_NlN2MessageTransfer service operation. The SMSF includes a Message Priority header to indicate priority information based on MPS for message indication and optionally priority level stored in the UE context. The AMF transfers the SMS message to the UE and may include a priority indication in the message for priority handling by the NG-RAN node. The priority indication is included at the N2 message level, i.e., message priority header.

[0071] Step 5c-5d. The UE acknowledges receipt of the SMS message to the SMSF 220. For uplink unitdata message toward the SMSF 200, the AMF 200 invokes Nsmsf_SMService_UplinkSMS service operation to forward the message to SMSF 220. The messages exchanged between AMF 200, SMSF 220, and / or AMF 200 and UE and NG-RAN node relaying the NAS messages to the UE include a priority indication based on MPS treatment for the SMS transported by those messages.

[0072] Step 6a-6b. The UE returns a delivery report as defined in TS 23.040. The delivery report is encapsulated in an NAS message and sent to the AMF 200 which is forwarded to SMSF 220 by invoking Nsmsf_SMService_UplinkSMS service operation.

[0073] Step 6c-6d. The SMSF 220 acknowledges receipt of the delivery report to the UE. The SMSF 220 uses Namf_Communication_NlN2MessageTransfer service operation to send SMS CP ack message to the AMF 200. The AMF 200 encapsulates the SMS message via a NAS message to the UE. If SMSF 220 has more than one SMS to send, the SMSF and the AMF forwards subsequent SMS / SMS ack / delivery report the same way as described in step 4-6c.

[0074] Similar to the above, all messages described in step 6 that are exchanged between AMF 200, SMSF 220, and / or AMF 200 and UE and NG-RAN node relaying the NAS messages to the UE include a Message priority header determined based on the MPS message information (table 1) and optionally the priority level stored in the UE context in the AMF and SMSF. The Message priority header enables MPS treatment of the messages during routing and processing.

[0075] Step 7. In parallel to steps 6c and 6d, the SMSF delivers the delivery report to SC as defined in TS 23.040 or TS 23.540 which includes a priority indication at the message level to secure priority handling of the message along the path to the SC and by the SC.

[0076] Figures 8 and 9 illustrate embodiments of methods implemented in AMF and SMSF respectively in accordance with embodiments described for Figures 5, 6 and 7.

[0077] In figure 8, the method performed by the AMF or similar function in a network comprises the step of obtaining the user subscription data from UDM as part of for example a registration procedure from the user equipment. The subscription data includes an additional indication of MPS for message / SMS. For example, the subscription data with the additional indication as described in table 1 above.

[0078] After the AMF determines the registration is for SMS or also for SMS, the AMF may then select an SMS function (SMSF) and the selection may be based on selecting an SMSF that supports priority handling. If for example the AMF needs to discover SMSF from a registry function, it may request discovery of SMSF that supports MPS handling, i.e., priority handling for the messages / SMSs.

[0079] The AMF informs the SMF with a service activate request indicating that the UE is registered or activated for SMS. The AMF would apply priority treatment by including a priority indicator to the request sent to the SMSF.

[0080] For MO SMS delivery, the AMF would apply priority indication to all messages transmitted to the SMSF and it should also indicate priority to the messages related to SMS transmitted to the NG-RAN node for transmission to the UE. This would enable the NG-RAN node to handle the N2 message or the NAS message including the SMS in the N2 message with priority when transmitting to the UE.

[0081] For MT delivery of SMS, when the AMF receives a reachability message from the SMSF for UE availability and if the UE is idle, the AMF can include paging priority in the paging message to the NG-RAN node based on the subscription data stored in theUE context (table 1) and / or the priority indication of the reachability message received from the SMSF. If the AMF determines the UE is reachable, it informs the SMSF, again with a priority indication added to the information message which is a response to the reachability message. Subsequent SMS delivery and report are handled with priority: i.e., applying priority treatment for the received message and including a priority indication to messages sent to the SMSF and optionally to the NG-RAN node in order to guarantee priority treatment. The messages to which priority treatment is applied include for example the message transfer that includes the SMS body and the acknowledgement, the messages indicating delivery reports as described in Figure 4,5, 6 above.

[0082] In figure 9, the method performed by a Short message service function or similar function providing SMS to be delivered over the NAS layer in a network is provided. The method comprises the step of obtaining the user subscription data from a User data management (UDM) as part of for example a registration procedure from the user equipment. The subscription data includes an additional indication of MPS for message / SMS. For example, the subscription data with the additional indication as described in table 1 above. The step may be triggered when receiving a service activation for a UE from an AMF indicating the UE is registered for SMS. The service activation message may also include a priority indication to enable MPS treatment of the message. The SMSF stores the subscription data as part of the UE context.

[0083] For MO SMS delivery, the SMSF would receive a message from the AMF comprising a SMS message body from the UE. The message may also include a priority indication for priority treatment by the SMSF. The SMSF would forward the SMS message body to a message center and includes a priority indication to the message based on the MPS subscription data for SMS and / or based on the priority indication received in the message from the AMF. The method comprises, when the SMSF receives a report from the message center indicating the message is delivered, the SMSF informs the AMF with another message (e.g., message transfer message) and adds a priority indication in the message based on the UE context and / or based on the priority indication if received in the report message from the message center. In some examples priority indication in the messages described in the embodiments of Figures 5, 6, 7, 8 and 9 is a message priority header set based on MPS for message indication obtained from the subscription data.

[0084] For MT delivery of SMS, when the SMSF receives a Mobile terminal (MT) SMS message from an SMS-GMSC (messaging gateway) or message center, if the message includes a message priority header the method comprises the SMSF applying priority treatment for the message by priority handling of the message. The SMSF processes the message and sends a reachability request message to the AMF serving the LIE. The SMSF includes a message priority header to the message based on the MPS subscription data stored in the UE context. Any subsequent communication messages from and to the AMF for completing the delivery of the SMS and handling of the delivery report from the AMF and to the message gateway or message center, the SMSF will include a message priority header set based on the MPS for message indication (i.e., the MPS for SMS indication obtained from the UDM.

[0085] In further embodiments, the messaging gateway or SMS-GMSC or SMS interworking messaging center can obtain the new indication MPS for message from UDM when requesting routing information from the UDM (e.g., step 2 in figure 7). The messaging gateway or SMS-GMSC or SMS-interworking messaging center can add message priority header when sending messages with SMS to the SMSF and the header could be set based on the obtained information from the UDM.Further Description

[0086] Figure 10 is a schematic block diagram of a network node 1100 according to some embodiments of the present disclosure. Optional features are represented by dashed boxes. The network node 1100 may be, for example, a core network node that implements a NF (e.g., AMF 200, SMF 206, SMSF220, NSACF 207, UDM 406, or the like). As illustrated, the network node 1100 includes a one or more processors 1104 (e.g., Central Processing Units (CPUs), Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs), and / or the like), memory 1106, and a network interface 1108. The one or more processors 1104 are also referred to herein as processing circuitry. The one or more processors 1104 operate to provide one or more functions of the network node 1100 as described herein (e.g., one or more functions of the AMF 200, SMF 206, SMSF220, NSACF 207, UDM 406, or the like, as described herein. In some embodiments, the function(s) are implemented in software that is stored, e.g., in the memory 1106 and executed by the one or more processors 1104.

[0087] Figure 11 is a schematic block diagram that illustrates a virtualized embodiment of the network node 1100 according to some embodiments of the present disclosure. Again, optional features are represented by dashed boxes. As used herein, a "virtualized" network node is an implementation of the network node 1100 in which at least a portion of the functionality of the network node 1100 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 1100 includes one or more processing nodes 1200 coupled to or included as part of a network(s) 1202. Each processing node 1200 includes one or more processors 1204 (e.g., CPUs, ASICs, FPGAs, and / or the like), memory 1206, and a network interface 1208. In this example, functions 1210 of the network node 1100 described herein (e.g., one or more functions of the AMF 200, SMF 206, SMSF220, NSACF 207, UDM 406, or the like, as described herein)are implemented at the one or more processing nodes 1200 or distributed across the two or more processing nodes 1200 in any desired manner. In some particular embodiments, some or all of the functions 1210 of the network node 1100 described herein are implemented as virtual components executed by one or more virtual machines implemented in a virtual environ ment(s) hosted by the processing node(s) 1200.

[0088] 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 the network node 1100 or a node (e.g., a processing node 1200) implementing one or more of the functions 1210 of the network node 1100 in a virtual environment according to any of the embodiments described herein is provided. In some embodiments, a carrier comprising the aforementioned computer program product is provided. The carrier is one of an electronic signal, an optical signal, a radio signal, or a computer readable storage medium (e.g., a non-transitory computer readable medium such as memory).

[0089] Figure 12 is a schematic block diagram of the network node 1100 according to some other embodiments of the present disclosure. The network node 1100 includes one or more modules 1300, each of which is implemented in software. The module(s) 1300 provide the functionality of the network node 1100 described herein. This discussion is equally applicable to the processing node 1200 of Figure 12 where themodules 1300 may be implemented at one of the processing nodes 1200 or distributed across multiple processing nodes 1200.

[0090] Any appropriate steps, methods, features, functions, or benefits disclosed herein may be performed through one or more functional units or modules of one or more virtual apparatuses. Each virtual apparatus may comprise a number of these functional units. These functional units may be implemented via processing circuitry, which may include one or more microprocessor or microcontrollers, as well as other digital hardware, which may include Digital Signal Processors (DSPs), special-purpose digital logic, and the like. The processing circuitry may be configured to execute program code stored in memory, which may include one or several types of memory such as Read Only Memory (ROM), Random Access Memory (RAM), cache memory, flash memory devices, optical storage devices, etc. Program code stored in memory includes program instructions for executing one or more telecommunications and / or data communications protocols as well as instructions for carrying out one or more of the techniques described herein. In some implementations, the processing circuitry may be used to cause the respective functional unit to perform corresponding functions according one or more embodiments of the present disclosure.

[0091] While processes in the figures may show a particular order of operations performed by certain embodiments of the present disclosure, it should be understood that such order is exemplary (e.g., alternative embodiments may perform the operations in a different order, combine certain operations, overlap certain operations, etc.).Embodiments:The following are few examples of non-limiting claim-like embodiments.

[0092] Some example embodiments of the present disclosure are as follows: Embodiment 1. A method performed by an Access and Mobility management Function (AMF) comprising:- obtaining subscription data for a UE comprising MPS for short message indication; and- upon signalling messages to a short message service function (SMSF) setting a message priority header based on the obtained MPS for shortmessage indication when the MPS for short message indication indicates MPS is to be applied for short message service.Embodiment 2. The method of embodiment 1 wherein the subscription data comprises a priority level for MPS.Embodiment 3. The method of any one of embodiment 1-2 wherein the method further comprises using the priority level when setting the message priority header.Embodiment 4. The method of any one of embodiments 1 to 3 wherein the method further comprises:- receiving a first message from the SMSF for requesting availability of the LIE for SMS, and- sending a paging message to an NG-RAN node for the UE in idle mode and including a paging priority determined based on the obtained short message indication and optionally the priority level.Embodiment 5. A method performed by a Short Message Service Function (SMSF) handling short message service for a UE, the method comprising:- obtaining subscription data for a UE comprising MPS for short message indication; and- upon signalling messages to an Access and mobility management function (AMF), setting a message priority header based on the obtained MPS for short message indication when the MPS for short message indication indicates MPS is to be applied for short message service.Embodiment 6. The method of embodiment 5 wherein the subscription data comprises a priority level for MPS.Embodiment 7. The method of any one of embodiments 5 to 6 wherein the method further comprises upon transmitting messages to a messaging gateway, setting a message priority header based on the obtained MPS for short message indicationwhen the MPS for short message indication indicates MPS is to be applied for short message service.Embodiment 8. The method of any one of embodiment 6 to 7 wherein the method further comprises using the priority level when setting the message priority level.Embodiment 9. A network node configured to perform the method of any of embodiments 1 to 8. Embodiment 10. A network node comprising one or more processors and memory comprising instructions which when executed by the one or more processors enable the network node to perform the method of any of embodiments 1 to 8.Embodiment 11. A computer readable memory comprising instructions which when executed by one or more processors of one or more servers configures the one or more servers to perform any of the embodiments 1 to 8.

[0093] Furthermore, the following is a related 3GPP contribution based on the embodiments described herein presenting changes to the standard to support the embodiments and may include additional details on the embodiments presented herein in Figure 5, 6, 7 8 and 9. The changes are proposed to a technical report (TR) which would be ported to a technical specification (TS number to be determined by 3GPP). The following embodiments are thus considered subject matter for potential claims as well:1. ProposalIt is proposed to accept the following changes to 3GPP TR 23.700-75 as a new solution to address the Kl#3.6.0 Mapping Solutions to Key IssuesTable 6.0-1 : Mapping Solutions to Key Issues6.x Solution #x: MPS support for SMS over NAS6.X.1 IntroductionNOTE 1: It is assumed that all NFs in a PLMN involved in the SMS over NAS delivery support MPS treatment when the feature is deployed.This solution provides methods to support MPS treatment for SMS over NAS, for UE with subscription data that indicates that SMS with MPS handling is included i.e., subscription in the UDM and / or on the USIM is used for priority treatment related to SMS over NAS.Editor's note: EPS related functional description and flows are FFS.6.X.2 Functional DescriptionThe solution is based on the current M PS-subscribed UE mechanism specified in TS 23.501 [7] with following high level descriptions:UE subscription data contains addition parameter indicating MPS treatment for message as part of the MPS subscription. This parameter is provided to related NFs involved in SMS over NAS (i.e. AMF and SMSF). Below table illustrate the possibility of setting of MPS related subscription data parameters.Table 6.X.2-1 : example of MPS related subscription data informationNOTE 2: UE subscription data includes the indication that “SMS delivery over NAS is subscribed” is a precondition.When establishing access network connection, the Establishment Cause is set based on MPS subscription as legacy and network treats the connection establishment with priority as legacy.When a CN entity, e.g. AMF, communicates with other NFs related to SMS over NAS service, the treatment of the signalling / message between NFs considers the additional parameter for MPS treatment for message.6.X.3 Procedures6.X.3.1Registration procedure for SMS over NASThe procedure is based on clause 4.13.3.1 of TS 23.502 [8] as illustrated in figure 6.x3.1 -1 below.Figure 5: Registration procedure supporting SMS over NASThe following steps, referring to steps in clause 4.13.3.1 of TS 23.502 [8] as base, are enhanced for the MPS treatment for SMS over NAS.1. The MPS-subscribed UE indicates the proper Establishment cause.NOTE 1: It’s anything new logically since this step referring to step 1-3 in figure 4.2.2.2.2-1 of TS 23.502 [8] which covers Establishment cause with MPS already. However the MPS treatment is not specific named in the SMS over NAS related procedure.2. The AMF may receive the additional MPS for message indication from UDM.5. The AMF includes a Message Priority header to indicate priority information based on MPS for message indication received in step 2 from UDM. The AMF may also provide the MPS for message indication as part of the Nsmsf SMService Active Request service operation.7b-7c. The SMSF may also receive the additional MPS for message indication from UDM as part of the SMS Management Subscription data.6.X.3.2M0 SMS over NAS procedureThe procedure is based on clause 4.13.3.3 and 4.13.3.5 of TS 23.502 [8] as illustrated in figure 6.x.3.2-1 below.Figure 6: MO SMS over NASThe following steps, referring to steps in clause 4.13.3.3 of TS 23.502 [8] as base, are enhanced for the MPS treatment for SMS over NAS.1. The MPS-subscribed UE indicates the proper Establishment cause.NOTE 1: It’s anything new logically since this step referring to step 1-3 in figure 4.2.2.2.2-1 of TS 23.502 [8] which covers Establishment cause with MPS already. However, the MPS treatment is not specific named in the SMS over NAS related procedure.2b. The AMF includes a Message Priority header to indicate priority information based on MPS for message indication if such information is stored in UE context (received during UE registration towards UDM).NOTE 2: The AMF applies the same in following steps when communicating with SMSF.3. The SMSF includes also the MPS for message indication if such information is stored in the UE context.6a. The SMSF includes a Message Priority header to indicate priority information based on MPS for message indication if such information is stored in UE context.6.X.3.3MT SMS over NAS procedureThe procedure is based on clause 4.13.3.6, 4.13.3.7 and 4.13.3.8 of TS 23.502 [8] as illustrated in figure 6.x.3.3-1 below.Figure 7: MT SMS over NASThe following steps, referring to steps in clause 4.13.3.6 of TS 23.502 [8] as base, are enhanced for the MPS treatment for SMS over NAS.2. The UDM indicates also that the UE is subscribed for MPS for message.3. The SMS-GMSC includes a Message Priority header to indicate priority information based on MPS for message indication if such information is such is received from UDM in step 2.4. The SMSF includes a Message Priority header to indicate priority information based on MPS for message indication if such information is stored in UE context.The AMF includes Paging Priority if Paging needs to be triggered and MPS for message indication is stored in UE context.The AMF includes a Message Priority header to indicate priority information based on MPS for message indication if such information is stored in UE context, when sending message towards SMSF.NOTE 1: The AMF and SMSF apply the same for Message Priority header in following steps when communicating with other NF using SBI interface.6.X.4 Impacts on services, entities, and interfacesUDM:Support MPS subscription data with additional indication MPS for message.AMF:Support receiving new indication MPS for message in subscription data.Support SMS related Message Priority header handling based on MPS for message indication.SMSF:Support receiving new indication MPS for message in subscription data from UDM or from AMF.Support SMS related Message Priority header handling based on MPS for message indication. SMS-GMSC / SMS-IWMSC:Support receiving new indication MPS for message from UDM.- Support SMS related Message Priority header handling based on MPS for message indication. UE:Support Establishment Cause based on MPS subscription including MPS for message.

[0094] Those skilled in the art will recognize improvements and modifications to the embodiments of the present disclosure. All such improvements and modifications are considered within the scope of the concepts disclosed herein.

Claims

Claims:

1. A method performed by an Access and Mobility management Function (AMF) comprising:- obtaining subscription data for a User Equipment (UE) comprising Multimedia Priority Services (MPS) for short message indication; and- setting a message priority header based on the obtained MPS for short message indication when the MPS for short message indication indicates MPS is to be applied for short message service in messages transmitted to a short message service function (SMSF) associated with the UE.

2. The method of claim 1 wherein the subscription data comprises a priority level for MPS.

3. The method of any one of claims 1 to 2 wherein the method further comprises using the priority level when setting the message priority header.

4. The method of any one of claims 1 to 3 wherein the method further comprises:- receiving a first message from the SMSF for requesting availability of the UE for Short Message Service (SMS), and- sending a paging message to a Radio Access node serving the UE in idle mode and including in the paging message a paging priority determined based on the obtained MPS for short message indication and optionally the priority level.

5. A method performed by a Short Message Service Function (SMSF) handling short message service for a User Equipment (UE), the method comprising:- obtaining for the UE, subscription data comprising Multimedia Priority Services (MPS) for short message indication; and- setting a message priority header based on the obtained MPS for short message indication when the MPS for short message indication indicates MPS is to be applied for short message service in messages transmitted to an Access & Mobility Management serving the UE.

6. The method of claim 5 wherein the subscription data comprises a priority level for MPS.

7. The method of any one of claims 5 to 6 wherein the method further comprises upon transmitting a message to a messaging gateway, setting a message priority header based on the obtained MPS for short message indication when the MPS for short message indication indicates MPS is to be applied for short message service.

8. The method of any one of claims 6 to 7 wherein the method further comprises using the priority level when setting the message priority level.

9. A network node configured to perform the method of any one of the claims 1 to 8.

10. A network node comprising one or more processors and memory comprising instructions which when executed by the one or more processors enable the network node to perform the method of any one of the claims 1 to 8.

11. A computer readable memory comprising instructions which when executed by one or more processors of one or more servers configures the one or more servers to perform any one of the claims 1 to 8.

Images