Method and apparatus for enabling a core network to perform mobility actions

Abstract

A method that enables the Core Network to determine the RAT type in a dual connectivity non-standalone configuration. The RAT type is either embedded by the RAN in the GTP‑U header, which is then extracted by the PGW‑U, or derived by the PGW‑U using an enhanced language proxy activated by the SPR through the PCRF and PGW‑C.

Description

Technical Field

[0001] The present disclosure generally relates to the field of mobile communication networks, and more particularly to mobility actions performed by a mobile communication network based on a Radio Access Technology (RAT) used by a User Equipment (UE) to connect to a core network. Background Art

[0002] 3GPP has defined different deployment scenarios for the upcoming 5G networks, such as non-standalone and standalone.

[0003] The non-standalone scenario to be deployed by the incumbent network operator is a basic migration from the existing fourth generation network to the fifth generation network. This scenario is also known as 5G NSA option 3, in which there is no 5G core network, and the new air interface NR (i.e. 5G radio access network RAN) is connected to the 4G evolved packet core EPC (i.e. 3GPP Rel15 version of the existing EPC), and in which the user equipment supports dual connectivity to both long-term evolution LTE (i.e. 4G RAN) and NR (i.e. 5G RAN). For more details refer to 3GPPTS23.401 Section 4.3.2a.

[0004] This particular disclosure focuses on 5G non-standalone NSA option 3 scenarios and can be applied to any other LTE / NR interworking solutions based on multi-radio dual connectivity, such as interworking solution options 1, 2, 4 and 7, where multiple Rx / Tx UEs can be configured to use resources provided by two different nodes connected via a non-ideal backhaul, one node providing NR access and the other providing E-UTRA or NR access. For more details on MR-DC refer to 3GPP TS 37.340.

[0005] In the case of 5G NSA Option 3 deployments, as explained in 3GPP TS23.401, it is currently not possible for the operator's core network to know the type of radio access technology (RAT) to which the UE is connected at any point during the IP-CAN session. In fact, in 5G NSA Option 3 deployments, currently, the RAT type is always set to LTE, even if the traffic is served by a secondary radio bearer on NR, or the traffic is split between LTE and NR radio bearers, and it is not possible to distinguish between 5G NSA and 4G users.

[0006] The operator's core network (e.g., Mobility Management Entity MME) may know whether an IP-CAN session is configured with dual connectivity, i.e., with a secondary RAT, but cannot know which access is used at a given time. In addition, 3GPP TS 37.340 (see Section 10.11) has defined a new procedure for the primary Node B (i.e., eNB in ​​the case of Option 3) to periodically report the secondary RAT PDCP volume usage (i.e., eNB in ​​the case of Option 3) and report to the MME / PGW as an alternative to PGW-U usage monitoring.

[0007] Such a charging solution as described above relies on radio access network RAN ​​support, low reporting period affecting NB performance, and NB service scheduling processing which is key to supporting low-latency services, and is not aligned with existing IP layer-based charging, and can be customized based on PGW service detection and transport protocol header observation (e.g. reporting volume when NR and excluding TCP retransmissions).

[0008] In addition to the charging exception, the PGW-U supports different implementation actions that can be significantly improved if the actual RAT type is known, for example:

[0009] • User plane traffic optimization, which may benefit from customized optimization profiles based on the actual RAT type.

[0010] Charging and reporting, where URR reports, and therefore CDRs, may benefit from including the actual RAT type, e.g. which traffic is carried on 4G RAN or 5G RAN.

[0011] Document EP3425940 discloses a gateway device configured to manage at least one bearer associated with information indicating first and second radio access technologies assigned to a communication terminal when the communication terminal performs a first radio communication using a first radio access technology and a second radio communication using a second radio access technology. Summary of the invention

[0012] In a first aspect of the present disclosure, a method is proposed to enable a gateway user plane GW-U node in a core network of a mobile communication network to perform mobility operations based on the type of radio access technology RAT used by a user equipment UE for conveying IP user data over an IP CAN bearer in an IP connectivity access network IP CAN session between the UE and an external Internet Protocol IP network.

[0013] The method comprises the following steps:

[0014] - receiving, by a gateway control plane GW-C node, a session creation message for creating the IPCAN session between the UE and the external IP network;

[0015] - Transmitting, by the GW-C node, a setup request message towards a policy and charging rules function PCRF node for retrieving a policy for the IP CAN session;

[0016] - receiving, by the GW-C node, a setup response message, wherein the setup response message comprises an indication that the core network intends to perform a mobility action based on a RAT type used by the UE for transporting the IP user data over the IP CAN bearer in the IP CAN session between the UE and the external IP network;

[0017] - selecting, by the GW-C node, a gateway user plane GW-U node based on the indication;

[0018] - The GW-C node transmits a session establishment request message to the selected GW-U node, wherein the session establishment request message includes the indication.

[0019] The inventors have found that during establishment of an IP CAN session between a UE and an external IP network, a gateway user plane GW-U node should be selected that is able to handle a dual connectivity capable UE.

[0020] In this way, the gateway control plane GW-C node should be informed that the core network (e.g. GW-U node) intends to perform mobility actions based on the RAT type used by the UE for transporting any IP user data over the IP CAN bearer in the IP CAN session between the UE and an external IP network.

[0021] The GW-C node can then select an appropriate GW-U node, i.e. a GW-U node that can handle the UE being dually connected to the core network. The GW-U node can then perform mobility actions, for example based on the type of RAT used by the UE for transporting IP user data over IP CAN bearers in an IP CAN session between the UE and an external IP network.

[0022] According to the present disclosure, the external IP network may be a public IP network like the Internet.

[0023] An IP-CAN or IP Connectivity Access Network is an access network that provides Internet Protocol IP connectivity. The term is usually used in a cellular context and usually refers to 3GPP access networks such as GPRS or EDGE, but can also be used to describe wireless LAN, WLAN or DSL networks. It was introduced in the 3GPP IP Multimedia Subsystem IMS standard as a generic term to refer to any kind of IP-based access network, because IMS places great emphasis on access and service network separation.

[0024] The method according to the present disclosure is particularly advantageous as it may enable network operators to apply different implementation actions based on the current RAT type, particularly in the case of dual connectivity in 5G NSA option 3 scenarios.

[0025] The implementation actions may for example be related to user plane traffic optimization, where the TCP / QUIC optimization profile depends on the actual RAT type.

[0026] Another implementation action may for example be related to charging / reporting per RAT type, ie reporting of service usage in a given RAT, or service chaining counters for users in a given RAT, which may be used to grant external SFs.

[0027] The proposed method can further avoid the need for statically pre-configured service optimization actions. The method allows adapting to changing network environments, such as changes in RAT types, and service characteristics.

[0028] No human intervention is required, the method can run autonomously, and the method also works for encrypted businesses.

[0029] The RAT type according to the present disclosure can be considered as the underlying physical connection of the UE towards a core network such as a wireless communication network. Example technologies are UTRA, UMTS Terrestrial Radio Access, CDMA2000, WiFi, GERAN, GSM EDGE Radio Access Network, LTE Long Term Evolution, New Radio NR, etc. Typically, the proposed disclosure is for a UE with dual connectivity capability, which is able to have two simultaneous connections, one to the LTE access network and one to the NR access network.

[0030] In the example, the indication is one of the following:

[0031] - an access node in the radio access network RAN ​​is to insert an indication of the RAT type in said IP user data packet;

[0032] - The gateway user plane node is to determine the indication of the RAT type by implementing a reinforcement learning agent (RLA) operating with an observation space comprising possible RAT types, a reward space comprising rewards related to the RAT type, and an action space comprising a set of user plane service implementation actions.

[0033] For example, the indication may be inserted into an IP user data packet by an access node in the radio access network RAN. The access node is for example an eNodeB in the case of a 4G RAN network, i.e. LTE, or a gNodeB in the case of a 5G RAN network, i.e. NR.

[0034] Another option is that the gateway user plane node is to determine the RAT type by implementing a reinforcement learning agent RLA operating with an observation space including possible RAT types, a reward space including rewards related to the RAT type, and an action space including a set of user plane service implementation actions. The above is basically a suitable process for estimating the RAT used by the UE for connecting to the core network by the gateway user plane node. This aspect is explained in more detail with reference to the accompanying drawings.

[0035] According to the present disclosure, PCRF may support different functionalities related to policy control, and specifically in the context of the present disclosure, PCRF supports retrieving subscriber policy profiles from a subscriber profile repository SPR and placing corresponding PCC rules / rules with requested enforcement actions towards PGW-C using the Gx interface.

[0036] The PGW-C node may support different functionalities, and specifically in the context of the present disclosure, the PGW-C retrieves one / multiple PCC rules from the PCRF via the Gx interface. The PGW-C also activates the corresponding PDR in the PGW-U via the packet forwarding control protocol PFCP protocol Sx interface to identify one / multiple target applications and implement actions FAR / QER / URR.

[0037] The PGW-U node can support different functionalities, and specifically in the context of the present disclosure, the PGW-U supports the handling of user plane services based on the PDR supplied by the PGW-C, including packet inspection, and different implementation actions based on the FAR / QER / URR supplied by the PGW-C.

[0038] In a second aspect of the present disclosure, there is provided a method for performing mobility operations based on a type of Radio Access Technology (RAT) used by a User Equipment (UE) for conveying IP user data over an IP Connectivity Access Network (IP CAN) bearer in an IP CAN session between the UE and an external Internet Protocol (IP) network.

[0039] The method comprises the following steps:

[0040] - The gateway user plane GW-U node receives IP user data packets via the IP CAN bearer;

[0041] - determining, by the GW-U node, the RAT type used by the UE for transporting the IP user data, and determining rules applicable to the IP user data packets based on the determined RAT type;

[0042] - Mobility operations are performed by the GW-U node based on the applicable rules.

[0043] The above aspect of the present disclosure is based on the same inventive concept as the first aspect of the present disclosure, but then from the perspective of a Gateway-User Plane GW-U node.

[0044] In this way, the GW-U node selected by the GW-C node receives the IP user data packet through the IP CAN bearer. The GW-U node determines the RATY used by the UE for transporting the IP user data, and determines the rules applicable to the IP user data packet based on the determined RAT type. Finally, the GW-U node performs mobility operations based on the applicable rules.

[0045] In this regard, the step of determining the RAT type may include any of the following:

[0046] - retrieving, by the GW-U node, the RAT type from the IP user data packet;

[0047] - determining the RAT type by the GW-U node by implementing a reinforcement learning agent RLA operating with an observation space comprising possible RAT types, a reward space comprising rewards related to the RAT type, and an action space comprising a set of user plane traffic implementation actions.

[0048] In a third aspect, there is provided a method for notifying a core network of a mobile communication network of a type of radio access technology (RAT) used by a user equipment (UE) for conveying IP user data over an IP Connectivity Access Network (IP CAN) bearer in an IP Connectivity Access Network (IP CAN) session between the UE and an external Internet Protocol (IP) network, wherein the method comprises the following steps:

[0049] - receiving IP user data packets by an access node in the radio access network RAN;

[0050] - inserting, by the access node, the RAT type in the IP user data packet;

[0051] - forwarding the IP user data packets to the core network by the access node over the IP CAN bearer, thereby informing the core network of the RAT for transporting the IP user data.

[0052] The above aspects describe the situation where an access node in a radio access network inserts a RAT type in an IP user data packet.

[0053] Here, the inserting step may include:

[0054] - inserting, by the access node, the RAT type in a GTP-U header of the IP user data packet.

[0055] Note that in any of the methods according to the present disclosure, the IP-CAN session has dual connectivity configured to enable the UE to connect to the core network using two types of RATs.

[0056] In another example, the mobile communication network is a fifth generation non-standalone based mobile communication network.

[0057] In a further aspect of the present disclosure, there is provided a gateway control plane GW-C node for enabling a gateway user plane GW-U node in a core network of a mobile communication network to perform mobility operations based on a type of radio access technology RAT used by a user equipment UE for conveying IP user data over an IP CAN bearer in an IP connectivity access network IP CAN session between the UE and an external Internet Protocol IP network.

[0058] The GW-C node includes:

[0059] - a receiving device, the receiving device being arranged to receive a session creation message for creating the IP CAN session between the UE and the external IP network;

[0060] - a transmitting device arranged for transmitting a setup request message towards a Policy and Charging Rules Function (PCRF) node for retrieving a policy for the IP CAN session;

[0061] wherein the receiving device is further arranged to receive a setup response message, wherein the setup response message comprises an indication that the core network intends to perform a mobility action based on a RAT type used by the UE for conveying the IP user data over the IP CAN bearer in the IP CAN session between the UE and the external IP network;

[0062] And wherein, the GW-C node further includes:

[0063] - a processing device arranged for selecting a Gateway User Plane GW-U node based on the indication;

[0064] And wherein the transmitting device is further arranged to transmit a session establishment request message to the selected GW-U node, wherein the session establishment request message includes the indication.

[0065] It will be appreciated that the disclosed apparatus may be implemented as separate hardware and / or software modules and devices, and / or may be implemented as a cloud service, and / or controlled by or executed in a processor or the like.

[0066] For a communication network comprised of a fifth generation 5G mobile communication network, in an embodiment, any of the nodes in the communication network may be arranged to operate as an application function AF of a service-based architecture SBA domain in a core network of the 5G mobile communication network.

[0067] In further examples, the indication is one of:

[0068] - an access node in the radio access network RAN ​​is to insert an indication of the RAT type in said IP user data packet;

[0069] - The gateway user plane node is to determine an indication of said RAT type by implementing a reinforcement learning agent RLA operating with an observation space comprising possible RAT types, a reward space comprising rewards related to said RAT type, and an action space comprising a set of user plane service implementation actions.

[0070] In a further aspect, there is provided a Gateway User Plane GW-U node arranged for performing mobility operations in a mobile communications network based on a type of Radio Access Technology (RAT) used by a User Equipment (UE) for conveying IP user data over an IP Connectivity Access Network (IP CAN) bearer in an IP CAN session between the UE and an external Internet Protocol (IP) network.

[0071] The GW-U node includes:

[0072] - a receiving device arranged for receiving IP user data packets over an IP CAN bearer;

[0073] - a processing device arranged for determining the RAT type used by the UE for transporting the IP user data, and determining applicable rules for the IP user data packets based on the determined RAT type, and performing mobility operations based on the applicable rules.

[0074] In an example, the processing device is arranged to determine the RAT type by any of the following:

[0075] - retrieving, by the GW-U node, the RAT type from the IP user data packet;

[0076] - determining the RAT type by the GW-U node by implementing a reinforcement learning agent RLA operating with an observation space comprising possible RAT types, a reward space comprising rewards related to the RAT type, and an action space comprising a set of user plane traffic implementation actions.

[0077] In yet another aspect, there is provided an access node in a radio access network RAN, for notifying a core network of a mobile communication network of a type of radio access technology RAT used by a user equipment UE for conveying IP user data over an IP CAN bearer in an IP Connectivity Access Network (IP CAN) session between the UE and an external Internet Protocol (IP) network.

[0078] Access nodes include:

[0079] - a receiving device arranged to receive IP user data packets;

[0080] - an inserting device arranged for inserting the RAT type in the IP user data packet;

[0081] - A transmitting device arranged for forwarding the IP user data packets to the core network over the IP CAN bearer, thereby informing the core network of the RAT for conveying the IP user data.

[0082] In a further example, the inserting device is further arranged for inserting the RAT type in a GTP-U header of the IP user data packet.

[0083] In yet another aspect, there is provided a computer program product comprising a computer readable medium having instructions stored thereon, which instructions, when executed on a node in a mobile communication network, cause the node to implement a method according to any of the examples provided above.

[0084] The above and other features and advantages of the present disclosure will be best understood from the following description with reference to the accompanying drawings. In the accompanying drawings, like reference numerals represent equivalent components or components that perform equivalent or similar functions or operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0085] Figure 1 Discloses deployment scenarios of different communication networks;

[0086] Figure 2 Disclosed is a PFCP extension for RAN exposure supporting RAT type feature negotiation according to the present disclosure;

[0087] Figure 3 and 4 A sequence diagram is disclosed in which an access node inserts a RAT type in a packet originating from a UE according to the present disclosure;

[0088] Figure 5 The architecture of the machine learning solution according to the present disclosure is disclosed;

[0089] Figure 6 A sequence diagram is disclosed in which a PGW-U is arranged to detect a RAT type used by a UE according to the present disclosure. DETAILED DESCRIPTION

[0090] Embodiments contemplated by the present disclosure will now be described in more detail with reference to the accompanying drawings. The disclosed subject matter should not be construed as being limited to the embodiments set forth herein. Instead, the illustrated embodiments are provided by way of example to convey the scope of the subject matter to those skilled in the art.

[0091] Figure 1 Two different deployment scenarios of the fifth-generation 5G communication network are disclosed, namely Figure 1 The dependent deployment depicted on the left and Figure 1 A standalone deployment is depicted on the right.

[0092] In a non-standalone deployment scenario, the communication network includes a single core network that is a 4G Evolved Packet Core (EPC) network. A specific UE can connect to the EPC network using two different radio access networks (RANs). In a first example, the UE can connect to the core network using a traditional 4G RAN that is a Long Term Evolution (LTE) RAN. In a second example, the UE can connect to the core network using an upcoming 5G RAN access network that is a New Radio (NR) RAN. The LTE network and the NR network can communicate with each other for various purposes.

[0093] Additionally, the UE may be a dual connectivity capable UE, where the UE is capable of connecting to the EPC in a dual manner, i.e., simultaneously via LTE and via NR.

[0094] In a standalone deployment scenario, such as Figure 1 As shown on the right side of the figure, the communication network includes two separate core networks, namely the 4G Evolved Packet Core EPC network and the 5G Core network. The 5G Core network is accessible via the NR Radio Access Network RAN, and the EPC network is accessible via the LTE RAN. In this particular scenario, the LTE RAN does not need to communicate directly with the NR RAN.

[0095] This disclosure is aimed at Figure 1 Non-standard deployment scenario depicted on the left. Currently, it is not possible for the operator's core network to know the type of radio access technology (RAT) to which the UE is connected at any point during an IP-CAN session. In fact, the RAT type is set to LTE even if the traffic is served by a secondary radio bearer on NR or the traffic is split between LTE and NR radio bearers. It is currently not possible to distinguish between 5G non-standalone users and 4G users.

[0096] The present disclosure is directed to the concept of a gateway control plane node selecting a gateway user plane node based on an indication by the core network that it intends to perform a mobility action based on the RAT type used by the UE for conveying IP user data over IP CAN bearers in an IP CAN session between the UE and an external IP network.

[0097] In one of the options, the RAT type is signaled to the core network. The RAN may mark the GTP-U header with the RAT type conveying the user traffic packet.

[0098] When the IP-CAN session is established / modified, the MME may provide dual connectivity indication to the PCRF, PGW-C and PGW-U by extending the S11, Gx and Sx (PFCP) protocols.

[0099] RAT type RAN exposure may be a feature negotiated by the RAN and the core network on a per-user IP-CAN session basis, particularly in the case of dual connectivity. At user IP-CAN session establishment / modification, both the indication of dual connectivity and activation of the GTP-U marking functionality may be delivered to the PGW-U via the PGW-C through the extension of the Gx and Sx (PFCP) protocols.

[0100] Finally, during an IP-CAN session, the RAN (e.g., a 4G RAN or 5G RAN) may mark the GTP-U header with the RAT type conveying the user traffic packets.

[0101] refer to Figure 3 and 4 The above options in which the RAN introduces indications in the transported traffic are explained in more detail.

[0102] In another option, the RAT type is based on reinforcement learning principles.

[0103] When the IP-CAN session is established / modified, the MME may provide dual connectivity indication to the PCRF, PGW-C and PGW-U by extending the S11, Gx and Sx (PFCP) protocols.

[0104] The RAT type feature based on reinforcement learning RL can be enabled by the policy and charging rules function PCRF on a per-user IP-CAN session basis, especially in the case of dual connectivity. At the time of the user's IP-CAN session establishment / modification, both the indication of dual connectivity and the activation of the RAT type feature based on RL can then be delivered to the PGW-U via the PGW-C through the extension of the Gx and Sx (PFCP) protocol.

[0105] At the PGW-U, the reinforcement learning agent may make decisions on implementation (eg, traffic optimization) actions (ie, action space) to apply to the user's application session.

[0106] At the PGW-U, the RAT type estimation module can act as the RL environment, sending the corresponding state and reward to the RL agent.

[0107] At the PGW-U, the network operator may use historical traces with different RAT types to train the model.

[0108] From a high-level point of view, an RL-based solution can be based on the following steps:

[0109] 1. The PGW-U associates to the PGW-C indicating that it supports the RL-based RAT type feature.

[0110] 2. The user establishes an IP-CAN session with dual connectivity (both 4G RAN and 5G RAN). The PCRF based on both the dual connectivity indication from the MME and the subscriber policy profile from the SPR can activate the RL-based RAT type feature in the PGW-C, for example by means of extending the Gx protocol.

[0111] 3. The PGW-C may select a PGW-U that supports the RL-based RAT type feature and activate it, for example, by means of the extended Sx / PFCP protocol.

[0112] 4. The user launches the application. The RAT type estimation module processes the application's traffic and may attempt to estimate the RAT type. The RAT type estimation module may send a status, such as an estimated RAT type or an "unestimated RAT type" status, and an associated reward to the RL agent.

[0113] 5. Based on the received states and rewards, the RL agent can learn the effects of past action decisions (e.g., business optimization).

[0114] 6. The RL agent can take action decisions (e.g., business optimization) based on the received state, the received reward, the set of possible actions, the business optimization action space, whether it is in exploration or exploitation mode, the learned policy, etc.

[0115] 7. Steps 4-6 can occur sequentially.

[0116] refer to Figure 5 and 6 Explain the above in a little more detail.

[0117] Figure 2 An association procedure 1 between a PGW-U and a PGW-C including RAN exposed PFCP extensions supporting RAT type feature negotiation is depicted.

[0118] At step 1): When the PGW-U 2 is deployed in the network, it may first need to associate to the PGW-C 3. In this regard, the PGW-U may send a PFCP association setup request message 4 to the PGW-C including the UP functional features it supports. It may also include an indication of a new feature: support of RAN exposure of the RAT type. In other words, support of the RAN includes the RAT type in the delivered service. This will allow the PGW-C to know which PGW-U support this capability and thus be able to influence the PGW-U selection.

[0119] At step 2): The PGW-C 3 replies to the Association Request with a PFCP Association Setup Response message 5 including the CP functional features it supports. It may also include an indication of new features, i.e. support of RAN exposure of RAT types as disclosed above.

[0120] NOTE: Step 1 may be triggered by PGW-U 2 or PGW-C 3. In the case it is triggered by PGW-C 3, PGW-C 3 may send an Association Request message including the CP feature to PGW-U 2, and the response includes the UP feature.

[0121] Figure 3 and 4 A sequence diagram in which an access node inserts a RAT type in a packet originating from a UE according to the present disclosure is disclosed.

[0122] The steps are outlined in a little more detail below.

[0123] Steps 21 and 22): The UE supporting dual mode connectivity is connected to both 4G RAN and 5G RAN, and triggers the IP-CAN session establishment procedure by sending an IP-CAN session establishment request to the MME. The message includes an indication to the MME that the IP-CAN session is to be established with dual mode connectivity.

[0124] Notice: Figure 3 and 4 The sequence diagram in does not include all signaling messages involved in the IP-CAN session establishment process. The relevant signaling messages used in the present disclosure are described in the subsequent steps.

[0125] Step 23) The mobility management entity MME selects the SGW-C / PGW-C instance to manage the IP-CAN session. The selection may be based on, for example, the local configuration of the SGW-C / PGW-C instance at the MME. For simplicity, it is assumed that both the SGW-C and the PGW-C are collocated. The MME triggers S11 towards the SGW-C / PGW-C a session creation including an indication that the IP-CAN session is to be established with dual-mode connectivity.

[0126] Step 24) The PGW-C triggers a Gx Setup Request message including an indication that the IP-CAN session is to be established with dual mode connectivity towards the PCRF to retrieve the policy for the user's IP-CAN session.

[0127] Step 25) The PCRF triggers a query request message including the IMSI identifying the subscriber to the SPR database to retrieve the policy data for the IP-CAN session of the user.

[0128] Step 26) The SPR replies with a query response message including subscriber policy data including policies to enable RAN exposure of the RAT type feature.

[0129] Step 27) PCRF generates corresponding one / multiple PCC rules based on the subscriber policy data. Since the IP-CAN session has dual-mode connectivity, it decides to enable RAN exposure of RAT type feature.

[0130] Step 28) Based on the above, the PCRF triggers a Gx Setup Response message including one / multiple PCC rules to be applied to the user IP-CAN session. In this case, as an example, there will be PCC rules for Skype applications including some implementation actions (i.e., charging and QoS, especially service optimization). The Gx Setup Response message may also include a request to enable RAN exposure of RAT type features.

[0131] Step 29) Based on the request to enable RAN exposure of RAT type feature, the PGW-C selects a PGW-U that supports RAN exposure of RAT type feature.

[0132] Step 30) PGW-C triggers a PFCP Session Establishment Request message including the corresponding PDR / FAR / QER / URR. In this case, there will be a PDR with a PDI of type application with appId=Skype, and the corresponding FAR, QER and URR. It is proposed to extend the PFCP Session Establishment Request message by creating a new IE to request the RAN exposure of RAT type features to be enabled.

[0133] Step 31) PGW-U stores the PDR / FAR / QER / URR and responds back to PGW-C with a PFCP Session Establishment Response message.

[0134] Steps 32 and 33) The user opens (ie starts) an application, such as Skype. In this example sequence diagram, it is assumed that the UE is on the 5G RAN, so the application service reaches the 5G RAN.

[0135] Steps 34 and 35) 5G RAN (i.e., access node in 5G RAN, such as gNodeB) inserts RAT type = 5G RAN in the GTP-U header.

[0136] Step 36) PGW-U extracts the RAT type from the GTP-U header, decapsulates the application service (ie, in the GTP-U payload), detects Skype service based on the PDR, and applies service optimization based on the RAT type.

[0137] Step 37) PGW-U forwards the application service towards the application server.

[0138] Figure 5 An architecture 51 of a machine learning solution according to the present disclosure is disclosed.

[0139] Here, the MME is indicated by reference numeral 52, the PGW-C is indicated by reference numeral 53, the PCRF is indicated by reference numeral 54, and the subscriber profile repository SPR is indicated by reference numeral 53. At any point in time, the PGW-C 53 indicates to the PGW-U 55 that reinforcement learning is to be enabled based on the RAT type.

[0140] Figure 6 A sequence diagram is disclosed in which a PGW-U is arranged to detect a RAT type used by a UE according to the present disclosure.

[0141] Steps 61 and 62) The UE supporting dual mode connectivity is connected to both 4G RAN and 5G RAN, and triggers the IP-CAN session establishment procedure by sending an IP-CAN session establishment request to the MME.

[0142] The message includes an indication to the MME that the IP-CAN session is to be established with dual mode connectivity. NOTE: Figure 5 The sequence diagram in does not include all signaling messages involved in the IP-CAN session establishment process. The relevant signaling messages used in the present disclosure are described in the subsequent steps.

[0143] Step 63) The MME selects a SGW-C / PGW-C instance to manage the IP-CAN session. The selection may be based on the local configuration of the SGW-C / PGW-C instance at the MME. For simplicity, it is assumed that both the SGW-C and the PGW-C are collocated. The MME triggers S11 towards the SGW-C / PGW-C a session creation including an indication that the IP-CAN session is to be established with dual mode connectivity.

[0144] Step 64) The PGW-C triggers a Gx Setup Request message including an indication that the IP-CAN session is to be established with dual mode connectivity towards the PCRF to retrieve the policy for the user's IP-CAN session.

[0145] Step 65) The PCRF triggers a query request message including the IMSI identifying the subscriber to the SPR database to retrieve the policy data for the IP-CAN session of the user.

[0146] Step 66) The SPR replies with a query response message including subscriber policy data including a policy for enabling RL-based RAT type features.

[0147] Step 67) PCRF generates corresponding one / multiple PCC rules based on the subscriber policy data. Since the IP-CAN session has dual-mode connectivity, it decides to enable the RL-based RAT type feature.

[0148] Step 68) Based on the above, the PCRF triggers a Gx setup response message including one / multiple PCC rules to be applied to the user IP-CAN session. In this case, as an example, there will be PCC rules for Skype applications including some implementation actions (billing and QoS, especially service optimization). The Gx setup response message will also include a request to enable RL-based RAT type features.

[0149] Step 69) Based on the request to enable the RL-based RAT type feature, the PGW-C selects a PGW-U that supports the RL-based RAT type feature.

[0150] Step 70) PGW-C triggers a PFCP Session Establishment Request message including corresponding PDR / FAR / QER / URR. In this case, there will be a PDR with a PDI of type application with appId=Skype, and corresponding FAR, QER and URR. It is proposed to extend the PFCP Session Establishment Request message by creating a new IE to request the enabling of RL-based RAT type features.

[0151] Step 71) PGW-U stores the PDR / FAR / QER / URR and responds back to PGW-C with a PFCP Session Establishment Response message.

[0152] Step 72) The user opens (starts) an application (eg Skype).

[0153] Step 73) PGW-U detects Skype application service based on the PDR information indicated above. If there is a match, the packet is classified as Skype and the RL-based RAT type feature will be applied.

[0154] Some advantages of the method according to the present disclosure include:

[0155] Network operators may apply different implementation actions based on the current RAT type, especially in the case of dual connectivity in 5G NAS Option 3 scenarios:

[0156] - User plane traffic optimization, where the TCP / QUIC optimization profile depends on the actual RAT type.

[0157] - Charging / reporting per RAT type (e.g. reporting of service usage in a given RAT, or service chaining counters for users in a given RAT, which may be used to grant external SFs).

[0158] It avoids the need for statically preconfigured service optimization actions. The solution allows adaptation to changing network environments (eg changes in RAT type) and service characteristics.

[0159] There is no need for human intervention. The solution operates autonomously and the solution works for crypto businesses.

[0160] In general, unless different meanings are clearly given and / or implied from the context in which it is used, all terms used in this article are interpreted according to their common meanings in the relevant technical field. Unless otherwise clearly stated, all references to (a / an) / (the) element, equipment, assembly, part, step, etc. are interpreted as referring to at least one instance of the element, equipment, assembly, part, step, etc. in an open manner. Unless a step is clearly described as following or prior to another step, and / or it is implied that a step must follow or precede another step, the steps of any method disclosed herein do not have to be performed in the exact order disclosed. In any appropriate case, any feature of any embodiment in the embodiments disclosed herein can be applied to any other embodiment. Similarly, any advantage of any embodiment in the embodiment can be applied to any other embodiment, and vice versa. According to the description, other purposes, features and advantages of the attached embodiments will be apparent.

[0161] The term unit may have the conventional meaning in the field of electronics, electrical devices and / or electronic devices, and may include, for example, electrical and / or electronic circuits, devices, modules, processors, memories, logical solid-state and / or discrete devices, computer programs or instructions for performing corresponding tasks, processes, calculations, output and / or display functions, etc., such as those described herein.

[0162] Some of the embodiments contemplated herein are described more fully with reference to the accompanying drawings. However, other embodiments are included within the scope of the subject matter disclosed herein. The disclosed subject matter should not be construed as being limited to the embodiments set forth herein; rather, these embodiments are provided as examples to convey the scope of the subject matter to those skilled in the art.

Claims

1. A method for enabling a gateway user plane GW-U node in a core network of a mobile communication network to perform mobility operations based on the type of radio access technology RAT used by a user equipment UE for conveying IP user data over an IP Connectivity Access Network IP CAN bearer in an IP Connectivity Access Network IP CAN session between the UE and an external Internet Protocol IP network, wherein: The method comprises the following steps: - receiving (23, 63) by a gateway control plane GW-C node a session creation message for creating the IP CAN session between the UE and the external IP network; - transmitting (24, 64) a setup request message by the GW-C node towards a policy and charging rules function PCRF node for retrieving a policy for the IP CAN session; - receiving (28, 68) a setup response message by the GW-C node, wherein the setup response message comprises an indication, the indication being one of: - an access node in the radio access network RAN ​​is to insert an indication of the RAT type in said IP user data packet; - the gateway user plane node is to determine the indication of the RAT type by implementing a reinforcement learning agent RLA operating with an observation space comprising possible RAT types, a reward space comprising rewards related to the RAT type, and an action space comprising a set of user plane service implementation actions; - selecting (29, 69) a gateway user plane GW-U node by the GW-C node based on the indication; - transmitting (30, 70) a session establishment request message by the GW-C node to the selected GW-U node, wherein the session establishment request message includes the indication.

2. A method for performing mobility operations in a mobile communication network based on the type of radio access technology (RAT) used by a user equipment (UE) for conveying IP user data over an IP Connectivity Access Network (IP CAN) bearer in an IP Connectivity Access Network (IP CAN) session between the UE and an external Internet Protocol (IP) network, wherein: The method comprises the following steps: - The gateway user plane GW-U node receives IP user data packets via the IP CAN bearer; -Determining, by the GW-U node, the RAT type used by the UE for transporting the IP user data, and determining rules applicable to the IP user data packets based on the determined RAT type, wherein determining the RAT type includes any one of the following: - retrieving, by the GW-U node, the RAT type from the IP user data packet; - determining, by the GW-U node, the RAT type by implementing a reinforcement learning agent RLA operating with an observation space comprising possible RAT types, a reward space comprising rewards related to the RAT type, and an action space comprising a set of user plane traffic implementation actions; - Mobility operations are performed by the GW-U node based on the applicable rules.

3. A method as claimed in any one of the preceding claims, wherein: The IP CAN session has dual connectivity configured to enable the UE to connect to a core network using two types of RATs.

4. A method as claimed in any one of the preceding claims, wherein: The mobile communication network is a fifth generation non-standalone based mobile communication network.

5. A gateway control plane GW-C node, for enabling a gateway user plane GW-U node in a core network of a mobile communication network to perform mobility operations based on a type of radio access technology RAT used by a user equipment UE for conveying IP user data over an IP Connectivity Access Network IP CAN bearer in an IP Connectivity Access Network IP CAN session between the UE and an external Internet Protocol IP network, wherein: The GW-C node includes: - a receiving device arranged to receive (23, 63) a session creation message for creating the IP CAN session between the UE and the external IP network; - a transmitting device arranged for transmitting (24, 64) a setup request message towards a Policy and Charging Rules Function (PCRF) node for retrieving a policy for the IP CAN session; The receiving device is further arranged to receive (28, 68) a setup response message, wherein the setup response message comprises an indication, the indication being one of: - an access node in the radio access network RAN ​​is to insert an indication of the RAT type in said IP user data packet; - the gateway user plane node is to determine the indication of the RAT type by implementing a reinforcement learning agent RLA operating with an observation space comprising possible RAT types, a reward space comprising rewards related to the RAT type, and an action space comprising a set of user plane service implementation actions; And wherein, the GW-C node further includes: - a processing device arranged for selecting (29, 69) a Gateway User Plane GW-U node based on the indication; And wherein the transmitting device is further arranged for transmitting (30, 70) a session establishment request message to the selected GW-U node, wherein the session establishment request message includes the indication.

6. A Gateway User Plane GW-U node arranged for performing mobility operations in a mobile communications network based on a type of Radio Access Technology (RAT) used by a User Equipment (UE) for conveying IP user data over an IP Connectivity Access Network (IP CAN) bearer in an IP CAN session between the UE and an external Internet Protocol (IP) network, wherein: The GW-U node includes: - a receiving device arranged for receiving IP user data packets over an IP CAN bearer; - a processing device arranged for determining the RAT type used by the UE for conveying the IP user data, and determining rules applicable to the IP user data packets based on the determined RAT type, and performing mobility operations based on the applicable rules; The processing device is arranged to determine the RAT type by any one of the following: - retrieving, by the GW-U node, the RAT type from the IP user data packet; - determining the RAT type by the GW-U node by implementing a reinforcement learning agent RLA operating with an observation space comprising possible RAT types, a reward space comprising rewards related to the RAT type, and an action space comprising a set of user plane traffic implementation actions.

7. A computer program product comprising a computer readable medium having instructions stored thereon, which instructions, when executed on a node in a mobile communication network, cause the node to implement the method according to any one of claims 1 to 4.

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