Patent ID: 12256298

DESCRIPTION

In context of SBA and the present disclosure some definitions are useful:Service Producer: An entity offering one or more services.Service consumer: An entity consuming a service.

Some of the embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. Other embodiments, however, are contained 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.

FIG.1illustrates one example of a cellular communications network200according to some embodiments of the present disclosure. In the embodiments described herein, the cellular communications network200is a 5G NR network. In this example, the cellular communications network200includes base stations202-1and202-2, which in LTE are referred to as eNBs and in 5G NR are referred to as gNBs, controlling corresponding macro cells204-1and204-2. The base stations202-1and202-2are generally referred to herein collectively as base stations202and individually as base station202. Likewise, the macro cells204-1and204-2are generally referred to herein collectively as macro cells204and individually as macro cell204. The cellular communications network200may also include a number of low power nodes206-1through206-4controlling corresponding small cells208-1through208-4. The low power nodes206-1through206-4can be small base stations (such as pico or femto base stations) or Remote Radio Heads (RRHs), or the like. Notably, while not illustrated, one or more of the small cells208-1through208-4may alternatively be provided by the base stations202. The low power nodes206-1through206-4are generally referred to herein collectively as low power nodes206and individually as low power node206. Likewise, the small cells208-1through208-4are generally referred to herein collectively as small cells208and individually as small cell208. The base stations202(and optionally the low power nodes206) are connected to a core network210.

The base stations202and the low power nodes206provide service to wireless devices212-1through212-5in the corresponding cells204and208. The wireless devices212-1through212-5are generally referred to herein collectively as wireless devices212and individually as wireless device212. The wireless devices212are also sometimes referred to herein as UEs.

FIG.2Aillustrates a 5G network architecture using service-based interfaces between the NFs in the control plane. Seen from the access side the 5G network architecture shown inFIG.2Acomprises a plurality of User Equipment (UEs) connected to either a Radio Access Network (RAN) or an Access Network (AN) as well as an Access and Mobility Management Function (AMF). Typically, the R(AN) comprises base stations, e.g. such as evolved Node Bs (eNBs) or 5G base stations (gNBs) or similar. Seen from the core network side, the 5G core NFs shown inFIG.2Ainclude a Network Slice Selection Function (NSSF), an Authentication Server Function (AUSF), a Unified Data Management (UDM), an AMF, a Session Management Function (SMF), a Policy Control Function (PCF), and an Application Function (AF). The service(s) etc. that a NF provides to other authorized NFs can be exposed to the authorized NFs through the service-based interface. InFIG.2A, 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 and Nsmf for the service based interface of the SMF etc.

Some properties of the NFs shown inFIG.2Amay be described in the following manner. The AMF provides UE-based authentication, authorization, mobility management, etc. A UE even using multiple access technologies is basically connected to a single AMF because the AMF is independent of the access technologies. The SMF is responsible for session management and allocates Internet Protocol (IP) addresses to UEs. It also selects and controls the UPF for data transfer. If a UE has multiple sessions, different SMFs may be allocated to each session to manage them individually and possibly provide different functionalities per session. The AF provides information on the packet flow to the PCF responsible for policy control in order to support Quality of Service (QoS). Based on the information, the PCF determines policies about mobility and session management to make the AMF and SMF operate properly. The AUSF supports authentication function for UEs or similar and thus stores data for authentication of UEs or similar while the UDM stores subscription data of the UE. The Data Network (DN), not part of the 5G core network, provides Internet access or operator services and similar.

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.

As previously described in the summary, with the current agreed solution in 3GPP TS 23.527 and the contribution C4-187420, the expected behavior to detect restart of peer service instance is by using recoveryTime attribute in Request/response, and take appropriate restoration or clean-up actions accordingly. However, in for example SMF with distributed collection scenario, the mechanism may not work properly.

In such a scenario, the SMF service instance received the request to create a PDU session (context) resource and may select another service instance to really create the resource. It is therefore proposed according to the embodiments herein to return the resource URI in for example the Location header of the response message to the service consumer. Subsequent operations on the created resource will go to the selected service instance, thus the resource should be associated with the selected service instance which is hosting the resource.

In accordance with some embodiment herein the service instance Id of the hosting SMF service instance should be provided in create and/or update service operations. This would result that the NF consumer can associate the resource with the correct service instance and implement the P2P restoration procedures.

FIG.3illustrates a deployment topology in accordance with an embodiment. An NF service instance, which is referred to a first service instance, can provide an Application Programming Interface Uniform Resource Identifier, API URI, root which is used by the NF service consumer for initiating the creation of resources or a resource URI which is used by the NF service consumer to update the resource, as shown inFIG.3, step1. When the requested resource is replicated in a second service instance, the HTTP/2 messages from the NF service consumer for the creation/update of resources at the NF service producer, is created on or transferred to the second (or other) service instance, as shown inFIG.3, Step2. The second service instance may be in the same network function or in a different NF providing the same service. Information such as the resource URI and service instance identification of the second (or other) service instance is included in the response to the NF Service Consumer, as illustrated in step3ofFIG.3. Other associated information may be included in the message at step3, such as recovery time or load information associated to the first service instance and/or the second service instance. The NF service consumer updates the association and maintains subsequent interactions with the resource in the new selected (second or other) service instance as shown in step4ofFIG.3.

In one embodiment, the service instance identification is provided in the 3GPP SMContextCreatedData and PDuSessionCreatedData types as well as the OpenAPI that are described in 3GPP TS 29.502. The attribute that supports the embodiment ofFIG.3is exemplified below (new attribute in bold and underlined):

SMContextCreatedData

TABLE 6.1.6.2.3-1Definition of type SmContextCreatedDataAttribute nameData typePCardinalityDescriptionhsmfUriUriC0 . . . 1This IE shall be present in HR roaming scenarios ifthe additionalHsmfUri IE was received in the requestand the V-SMF established the PDU sessiontowards an alternative SMF listed in theadditionalHsmfUri IE. When present, it shall containthe URI of the H-SMF towards which the PDUsession was established.pduSessionIdPduSessionIdC0 . . . 1This IE shall be present, during an EPS to 5GS Idlemode mobility or handover using the N26 interface.When present, it shall be set to the PDU Session ID.sNssaiSnssaiC0 . . . 1This IE shall be present during an EPS to 5GS Idlemode mobility or handover using the N26 interface.When present, it shall contain the S-NSSAI assignedto the PDU session.upCnxStateUpCnxStateC0 . . . 1This IE shall be present if the SMF was requested toactivate the user plane connection of the PDUsession in the corresponding request.When present, it shall be set as specified insubclause 5.2.2.2.2.n2SmInfoRefToBinaryDataC0 . . . 1This IE shall be present if N2 SM Information needsto be sent to the AN.n2SmInfoTypeN2SmInfoTypeC0 . . . 1This IE shall be present if “n2SmInfo” attribute ispresent.When present, this IE shall indicate the NG AP IEtype for the NG AP SMF related IE container carriedin “n2SmInfo” attribute.allocatedEbiListarray(EbiArpmapping)C0 . . . NThis IE shall be present if the consumer NF is anAMF and Inter-system mobility happens. Whenpresent, it shall contain an array of EBI to ARPmappings currently allocated to the PDU session.hoStateHoStateC0 . . . 1This IE shall be present if the SMF was requested toprepare an EPS to 5GS handover for the PDUsession in the corresponding request.When present, it shall be set as specified insubclause 5.2.2.2.3.smfServiceInstanceIdstringO0 . . . 1When present, this IE shall contain theserviceInstanceId of the SMF service instanceserving the PDU session Context.This IE may be used by the AMF to identify PDUsession contexts affected by a failure or restartof the SMF service instance (see subclause 6.2of 3GPP TS 23.527 [24]).supportedFeaturesSupportedFeaturesC0 . . . 1This IE shall be present if at least one optionalfeature defined in subclause 6.1.8 is supported.
PduSessionCreatedData

TABLE 6.1.6.2.10-1Definition of type PduSessionCreatedDataAttribute nameData typePCardinalityDescriptionpduSessionTypePduSessionTypeM1This IE shall indicate the selected PDU type.sscModestringM1This IE shall indicate the SSC mode applicable tothe PDU session.When present, it shall be encoded as one characterin hexadecimal representation, taking a value of “0”to “9” or “A” to “F”, representing the 4 bits of theSSC mode value of the SSC mode IE specified insubclause 9.8.4.10 of 3GPP TS 24.501 [7].Example: SSC mode 3 shall be encoded as “3”.See NOTE.hcnTunnelInfoTunnelInfoM1This IE shall contain the N9 tunnel information on thehome CN side.sessionAmbrAmbrM1This IE shall contain the Session AMBR granted tothe PDU session.qosFlowsSetupListarray(QosFlowSetupItem)M1 . . . NThis IE shall contain the set of QoS flow(s) toestablish for the PDU session. It shall contain atleast the Qos flow associated to the default Qos rule.pduSessionIdPduSessionIdC0 . . . 1This IE shall be present during an EPS to 5GS Idlemode mobility or handover preparation using theN26 interface.When present, it shall be set to the PDU Session ID.sNssaiSnssaiC0 . . . 1This IE shall be present during an EPS to 5GS Idlemode mobility or handover using the N26 interface.When present, it shall contain the S-NSSAI assignedto the PDU session in the Home PLMN.enablePauseChargingbooleanC0 . . . 1This IE shall be present, based on operator's policy,to enable the use of Pause of Charging for the PDUsession (see subclause 4.4.4 of3GPP TS 23.502 [3]).When present, it shall be set as follows:true: enable Pause of Charging;false (default): disable Pause of Charging.uelpv4AddressIpv4AddrC0 . . . 1This IE shall be present if the H-SMF assigns a UEIPv4 address to the PDU session.uelpv6PrefixIpv6PrefixC0 . . . 1This IE shall be present if the H-SMF assigns a UEIPv6 prefix to the PDU session.n1SmInfoToUeRefToBinaryDataC0 . . . 1This IE shall be present if the H-SMF needs to sendN1 SM information to the UE that does not need tobe interpreted by the V-SMF. When present, this IEshall reference the n1SmInfoToUe binary data (seesubclause 6.1.6.4.4).epsPdnCnxInfoEpsPdnCnxInfoC0 . . . 1This IE shall be present if the PDU session may bemoved to EPS during its lifetime.epsBearerInfoarray(EpsBearerInfo)C1 . . . NThis IE shall be present if the PDU session may bemoved to EPS during its lifetime.supportedFeaturesSupportedFeaturesC0 . . . 1This IE shall be present if at least one optionalfeature defined in subclause 6.1.8 is supported.upSecurityUpSecurityO0 . . . 1When present, this IE shall indicate the securitypolicy for integrity protection and encryption for theuser plane of the PDU session.hSmfServiceInstanceIdstringO0 . . . 1When present, this IE shall contain theserviceInstanceId of the H-SMF service instanceserving the PDU session.This IE may be used by the V-SMF to identifyPDU sessions affected by a failure or restart ofthe H-SMF service (see subclause 6.2 of3GPP TS 23.527 [24]).NOTE:This IE contains information that the V-SMF only needs to transfer to the UE (without interpretation). It is sent as a separate IE rather than within the n1SmInfoToUE binary data because the Selected SSC mode IE is defined as a “V” IE (i.e. without a Type field) in the NAS PDU Session Establishment Accept message.

Furthermore, currently 3GPP TS 29.518 has specified that AMF shall notify a consumer for subscription Id change, when a new subscription has been created with new subscription id during inter-AMF mobility procedures.

The present state of the art describes that in the notification, the new subscriptionId together with the notifyCorrelationId (or subscriptionChangeCorrelationId when available) will be included to the consumer, so the consumer could learn which subscription has been changed. The subscriptionId is expected to be the resource identifier of the new subscription on the new AMF, which in fact cannot be directly used by the consumer to perform subsequent service operations, e.g. to update or unsubscribe the event subscription after inter-AMF mobility. The embodiment presented herein mitigate the problem by proposing to include the resource URI of the new subscription instead in the subscription change notification, thus the consumer could use it as expected. This is also illustrated inFIG.3.

To further describe how the above problem can be mitigated, an embodiment describing replacing the currently defined 3GPP “SubscriptionId” data type with SubscriptionUri” data type in the AmfEventNotification and is proposed.

AmfEventNotification

TABLE 6.2.6.2.4-1Definition of type AmfEventNotificationAttribute nameDate typePCardinalityDescriptionnotifyCorrelationIdstringM1Indicates the notification correlation ID provided bythe NF service consumer during event subscription.This parameter can be useful if the NF serviceconsumer uses a common call-back URI for multiplesubscriptions.subscriptionUriUriC0 . . . 1This IE shall be present, if the event notificationis generated by the AMF due to a change of AMF.When present, this IE shall contain the URI to thesubscription resource created at the new AMFwhich replacing the original subscription on theold AMF.reportListarray(AmfEventReport)C1 . . . NThis IE shall be present if a event is reported. Whenpresent, this IE represents the event reports to bedelivered.

FIG.4illustrates a NF Service restart scenario of an NF Service Producer and how the NF Service Consumer can detect this restart, according to some embodiments.

Step40: NF A requests to create a resource in the NF B, and the NF B accepts the request. The NF A shall associate the created resource with the service instance in the NF B.

Step41: A NF service produced by NF B restarts.

Steps42-43: NF B service may include its last recovery timestamp in responses it sends to the NF Service Consumer, if the restart of the NF service resulted in losing contexts and e.g. if the NF service has restarted recently.

Step44: NF A may consider that all the resources created in the NF B service instance before the NF B service recovery time as being lost. NF A triggers the appropriate restoration or clean-up actions.

The recovery timestamp signalled in direct signalling between NFs shall be associated to a NF service instance, i.e. the same recovery timestamp shall be signalled by a NF service instance whatever the NF service instance's endpoint addresses used for the signaling. The procedure illustrated inFIG.4is only supported by NF services that support signalling the recoveryTime attribute.

Note that the recovery time signalled is equivalent to the recovery time of the NF service ofFIG.6.2.3-2. For an entire NF restart scenario, this procedure can be applied by each NF service instance of the NF.

The procedure illustrated inFIG.4enables the detection of a restart of a peer NF service when sending signalling towards that NF Service. It can speed-up the detection of a restart of a peer NF service when frequent signalling occur towards that peer NF Service.

FIG.5illustrates a method500executed at an NF service producer, such as an SMF of a 5G Core network in accordance with some embodiments. The method comprises the step510of receiving, at the NF service producer, a request message to create or update a resource and where the message is for example an hypertext transport protocol/REpresentational State Transfer HTTP/REST POST message or similar. The request message may also include an identifier of a service instance where the resource is to be created or updated. At step520, the step of selecting a service instance at the NF service producer in order to create the requested resource or to update the requested resource is performed. This may be the case if for example the service instance in the request message (requested service instance) is restarted or failed. The resource is replicated in the selected service instance. The selected service instance may be different than the service instance included in the request message if one was included. In addition, the selected service instance may be on the same or another NF acting as a service producer for the same service.

At step530, the step of sending, by the NF service producer, a response message to the received request from the NF service consumer and where the response message comprises a Uniform Resource Identifier, URI, for the created or updated resource together with information associated with the selected service instance and where the information comprises an identification of the selected service instance and may comprise a recovery time of the selected service instance (if restarted). Furthermore, the information further comprises information related to at least an overload information and a load information of the requested service instance and/or the selected service instance.

FIG.6illustrates a method600executed at an NF service consumer, such as an AMF of a 5G Core network in accordance with some embodiments. The method600comprises the step610of sending by the NF service consumer to an NF service producer a request message to create or update a resource indicating the service instance for the requested/updated resource. At step620, the NF service consumer, receiving a message in response to the request message and where the response message comprises a Uniform Resource Identifier, URI, for the created or updated resource as well as an identifier of the service instance where the resource is created or updated at the NF service producer and where the identifier of the service instance included in the response message may be different from the service instance included in the request message. This may be the case in the event of a restart of the service instance included in the request message.

If the NF service consumer receives an identifier of a service instance for the requested/updated resource that is different from the service instance included in the request, the NF service consumer proceeds with associating the created or updated resource with the second service instance and sending subsequent resource related messages to the service instance identified by the NF service producer in the response message.

Additionally, the method600may, at step620, further comprises receiving at the NF service consumer, perhaps within the same response message, information related to an overload information and/or a load information associated to the requested service instance included the request message and/or to the service instance selected by the NF service producer and included in the response message.

FIG.7is a schematic block diagram of a network node800according to some embodiments of the present disclosure. The network node may be a radio access node (e.g., a base station or other node in the radio access network) or a core network (e.g., a physical node that implements one or more core network NFs and/or core network services). As illustrated, the network node800includes a control system802that includes one or more processors804(e.g., Central Processing Units (CPUs), Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs), and/or the like), memory806, and a network interface808. The one or more processors804are also referred to herein as processing circuitry.

In addition, in embodiments in which the network node800is a radio access node, the network node800includes one or more radio units810that each includes one or more transmitters812and one or more receivers814coupled to one or more antennas816. The radio units810may be referred to or be part of radio interface circuitry. In some embodiments, the radio unit(s)810is external to the control system802and connected to the control system802via, e.g., a wired connection (e.g., an optical cable). However, in some other embodiments, the radio unit(s)810and potentially the antenna(s)816are integrated together with the control system802.

The one or more processors804operate to provide one or more functions of a network node800, and in particular the functions of a network function(s) or service(s), as described herein. In some embodiments, the function(s) are implemented in software that is stored, e.g., in the memory806and executed by the one or more processors804.

FIG.8is a schematic block diagram that illustrates a virtualized embodiment of the network node800according to some embodiments of the present disclosure. This discussion is equally applicable to other types of network nodes. Further, other types of network nodes may have similar virtualized architectures.

As used herein, a “virtualized” network node is an implementation of the network node800in which at least a portion of the functionality of the network node800is 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 some embodiments, the network node800includes the control system802that includes the one or more processors804(e.g., CPUs, ASICs, FPGAs, and/or the like), the memory806, and the network interface808and, if the network node800is a radio access node, the one or more radio units810that each includes the one or more transmitters812and the one or more receivers814coupled to the one or more antennas816, as described above. The control system802is connected to one or more processing nodes900coupled to or included as part of a network(s)902via the network interface808. Each processing node900includes one or more processors904(e.g., CPUs, ASICs, FPGAs, and/or the like), memory906, and a network interface908.

In this example, functions910of the network node800(e.g., functions of the network function(s) or service(s) implemented by the network node800) described herein are implemented at the one or more processing nodes900or distributed across the control system802and the one or more processing nodes900in any desired manner. In some particular embodiments, some or all of the functions910of the network node800described herein are implemented as virtual components executed by one or more virtual machines implemented in a virtual environment(s) hosted by the processing node(s)900. As will be appreciated by one of ordinary skill in the art, additional signaling or communication between the processing node(s)900and the control system802is used in order to carry out at least some of the desired functions910.

In some embodiments, a computer program including instructions which, when executed by at least one processor, causes the at least one processor to carry out the functionality of network node800or a node (e.g., a processing node900) implementing one or more of the functions910of the radio access node800in 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).

FIG.9is a schematic block diagram of the network node800according to some other embodiments of the present disclosure. The network node800includes one or more modules1000, each of which is implemented in software. The module(s)1000provide the functionality of the network node800described herein. This discussion is equally applicable to the processing node900ofFIG.8where the modules1000may be implemented at one of the processing nodes900or distributed across multiple processing nodes900and/or distributed across the processing node(s)900and the control system802.

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 Processor (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.

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.).

EXAMPLE EMBODIMENTS

While not being limited thereto, some other example embodiments of the present disclosure are provided below. Note that these are merely examples and may not necessarily be the final claims.1. A method of operation of a network node (800) implementing a network function, NF, service producer in a core network, the method comprising:receiving at a first service instance of the NF service producer in a request to create or update a resource via HTTP/REST signaling;selecting a second service instance to create requested resource or update the requested resource which is replicated in the second service instance; andsending a response to the received request comprising a resource Uniform Resource Identifier, URI, together with information associated with the second service instance.2. The method of embodiment 1, wherein the second service instance is on the same or another network function, NF, which act as a service producer for a same service.3. The method of embodiment 1, wherein the information further comprises an identification of the second service instance and an indication that a different service instance is returned in the response.4. The method of embodiment 1 wherein the information further comprises a recovery time of the at least one of the first service instance or the second.5. The method of embodiment 1 wherein the information further comprises information related at least an overload information and a load information of the first service instance and/or the second service instance.6. A network node (800) implementing a network function, NF, service producer in a core network of a cellular communications system, adapted to perform the method of any one of embodiments 1 to 5.7. A network node (800) implementing a network function, NF, service producer in a core network of a cellular communications system, comprising:one or more processors; andmemory comprising instructions executable by the one or more processors whereby the network node is adapted to perform the method of any one of embodiments 1 to 5.8. A network node (800) implementing a network function, NF, service producer in a core network of a cellular communications system, comprising:one or more modules operable to perform the method of any one of embodiments 1 to 5.9. A method of operation of a network node (800) implementing a network function, NF, service consumer in a core network of a cellular communications system, comprising:sending to a first service instance of an NF service producer a request to create or update a resource via HTTP/REST signaling;receiving a response comprising a resource Uniform Resource Identifier, URI, of the created or updated resource at a second service instance and a service instance identifier identifying the second service instance.10. The method of embodiment 8 further comprising sending subsequent HTTP messages to the second service instance.11. A network node (800) implementing a network function, NF, service consumer in a core network of a cellular communications system, adapted to perform the method of any one of embodiments 9 to 10.12. A network node (800) implementing a network function, NF, service consumer in a core network of a cellular communications system, comprising:one or more processors; andmemory comprising instructions executable by the one or more processors whereby the network node is adapted to perform the method of any one of embodiments 9 to 10.13. A network node (800) implementing a network function, NF, service consumer in a core network of a cellular communications system, comprising:
one or more modules operable to perform the method of any one of embodiments 9 to 10.

ABBREVIATIONS

At least some of the following abbreviations may be used in this disclosure. If there is an inconsistency between abbreviations, preference should be given to how it is used above. If listed multiple times below, the first listing should be preferred over any subsequent listing(s).3GPP Third Generation Partnership Project5G Fifth Generation5GC Fifth Generation CoreAMF Access Management FunctionAPI Application Program InterfaceASIC Application Specific Integrated CircuitAUSF Authentication Service FunctionCPU Central Processing UnitCT Core Network and TerminalsDSP Digital Signal ProcessoreNB Enhanced or Evolved Node BFPGA Field Programmable Gate ArraygNB New Radio Base StationHTTP Hypertext Transfer ProtocolLTE Long Term EvolutionNF Network FunctionNR New RadioRAM Random Access MemoryRAN Radio Access NetworkREST Representational State TransferROM Read Only MemoryRRH Remote Radio HeadSBA Service-Based ArchitectureSMF Session Management FunctionUDM User Data ManagerUDP User Datagram ProtocolUE User Equipment