WO2025045610A1

WO2025045610A1 - Method for managing an energy usage in a mobile communications network

Info

Publication number: WO2025045610A1
Application number: PCT/EP2024/073120
Authority: WO
Inventors: Lasse Olsson; Ralf Keller; Paul Schliwa-Bertling
Original assignee: Telefonaktiebolaget LM Ericsson AB
Current assignee: Telefonaktiebolaget LM Ericsson AB
Priority date: 2023-08-31
Filing date: 2024-08-16
Publication date: 2025-03-06
Anticipated expiration: 2026-02-28

Abstract

The invention concerns a method (10) for a mobile communications network (1), the method comprising Determining (11), by a core network (2), whether an energy efficiency accepted indicator is set for a user equipment, UE (4), wherein the energy efficiency accepted indicator is indicating whether energy saving functionalities should be applied; and Transmitting (12), by the core network (2), a message to a radio access network, RAN (3), wherein the message is indicating that the energy efficiency accepted indicator is set for the UE, if it is determined that the energy efficiency accepted indicator is set for the UE.

Description

Method for managing an energy usage in a mobile communications network

Technical field

The invention refers to a method for managing an energy usage in a mobile communications network.

Background

Mobile communications networks are commonly designed to work in a energy efficient way. However, there can be a conflict between being energy efficient and providing a highest possible Quality of Service (QoS) for the communication for a user equipment.

US11678215B2 discloses that a user equipment can transmit an energy efficiency indicator to a base station to indicate that a lower QoS is acceptable for the UE, which allows the UE and the base station to set a priority of the UE quality of service over UE energy constraints.

A method for a mobile communications network according to the invention comprises determining, by a core network, whether an energy efficiency accepted indicator is set for a user equipment (UE), wherein the energy efficiency accepted indicator is indicating whether energy saving functionalities should be applied for the UE; and transmitting, by the core network, a message to a radio access network (RAN), wherein the message is indicating that the energy efficiency accepted indicator is set for the UE, if it is determined that the energy efficiency accepted indicator is set for the UE.

The core network is preferably a 5G core network. It is determined by the core network whether the energy efficiency accepted indicator is set for the user equipment. The energy efficiency accepted indicator is preferably set by a subscription data provisioning system, and it is determined whether the efficiency active indicator was set by the subscription data provisioning system. The subscription data provisioning system is preferably setting the energy efficiency accepted indicator as a parameter in a Unified Data Repository (UDR) and it is determined whether the efficiency active indicator was set by reading out the parameter from the UDR. The energy efficiency accepted indicator is set as a parameter that is linked to the UE, wherein the energy efficiency accepted indicator can be applicable for one UE or a group of UEs. The energy efficiency accepted indicator is indicating whether energy saving functionalities should be applied for the UE. Energy saving functionalities are all types of possible actions that lead to a reduced consumption of energy that is caused by a usage of the UE. This includes a consumption of energy by the RAN, the UE and/or the core network. The energy saving functionalities in particular comprise such actions that lead to a decrease in a quality of service (QoS) for the UE for the price of a reduced energy consumption when compared to a handling of the UE without applying the energy saving functionalities.

A message is transmitted by the core network to the RAN, wherein the message is indicating that the energy efficiency accepted indicator is set for the UE, if it is determined that the energy efficiency accepted indicator is set for the UE. The message is transmitted to the RAN but the RAN is not necessarily the final receiver that is addressed by the message. In particular, the message or the energy efficiency accepted indicator can be forwarded by the RAN to the UE, which is connected to the RAN.

The energy efficiency accepted indicator can be a parameter in the format of a single bit or a string of bits. In particular, one value of the parameter is indicating that the efficiency active indicator is set and another value of the parameter is indicating that the efficiency active indicator is not set. For example, the value of “1” indicates that the efficiency active indicator is set and the value of “0” indicates that the efficiency active indicator is not set, or vice versa.

The message that is indicating that the energy efficiency accepted indicator is set for the UE is transmitted, if it is determined that the energy efficiency accepted indicator is set for the UE. In other words, the message is transmitted in reaction to the determination that the energy efficiency accepted indicator is set for the UE. The message is preferably comprises the energy efficiency accepted indicator as a parameter with a pre-defined first value to indicate that the energy efficiency accepted indicator is set for the UE. Optionally, if it is determined that the efficiency active indicator is not set for the UE, the message comprises the energy efficiency accepted indicator as a parameter with a pre-defined second value to indicate that the energy efficiency accepted indicator is not set for the UE.

Transmitting the message that is indicating that the energy efficiency accepted indicator is set for the UE allows the core network to inform the RAN and/or the UE about the energy efficiency accepted indicator. This is achieved by adapting the protocols and internal logic of the core network, in particular by adapting a non-access stratum protocol for communication to the UE and/or a next generation application protocol for communication to the RAN. The logic can apply to a single UE and might therefore be connected to the subscription data or policies for that UE. In the alternative the logic can be applied on a network level or its sub-level (e.g., set of cells or a geographical area) where all UEs are treated the same way (i.e., to prioritize low carbon footprint over performance). Once the RAN becomes aware about the energy efficiency accepted indicator, it can use that information for RAN internal decisions, well knowing that energy consumption (carbon footprint) is more important than pure connectivity performance for a particular UE.

The message is transmitted to a radio access network (RAN). This includes a direct and an indirect transmission. For example, one entity of the core network determines whether the energy efficiency accepted indicator is set for the UE and is forwarding this information to a second entity of the core network. The second entity of the core network is then transmitting the message that is indicating that the energy efficiency accepted indicator is set for the UE to the RAN.

Preferably, the message is indicating that the energy efficiency accepted indicator is not set for the UE, if it is determined that the energy efficiency accepted indicator is not set for the UE. Thus, it can be explicitly communicated to the RAN and/or to the UE that no or no additional energy saving measures are desired for the UE. Therefore, it can be ensured that a high QoS is preferred over low energy consumption for the UE.

The energy efficiency accepted indicator is not necessarily limited to exact two values, for example “set” and “not set” or “1” and “0”, but might also be an indicator that is indicating a level of energy efficiency that is desired, as different UEs might accept a different QoS for the price of different levels of energy saving.

Preferably, the Determining whether the energy efficiency accepted indicator is set for the UE comprises fetching the energy efficiency accepted indicator from the UDR of the core network. This allows that a subscriber can easily set the energy efficiency accepted indicator for UEs that are assigned to this subscriber.

Preferably, the message is transmitted to a base station of the RAN. The base station is in particular a base station that the UE is connected to. As the base station is handling the wireless communication with the UE, the base station can take measures to reduce the energy consumption that is caused by the wireless communication. Preferably, the message is transmitted to the base station of the RAN over next generation application protocol, NGAP, wherein the message is preferably one of the following: an Initial Context Setup Request, a UE Context Modification Request, a DL NAS Transport, a Handover Request, a Path Switch Request Acknowledge, a UE Context Resume Response, a Connection Establishment Indication, an AMF CP Relocation Indication, a UE Context Suspend Response, a UE Information Transfer, a PDU Session Resource Setup Request, a PDU Session Resources Modify Request, or a PDU Session Resource Modify Confirm.

Preferably, the base station is performing a first action to reduce an energy consumption for the UE in response to receiving the message that is indicating that the energy efficiency accepted indicator is set for the UE. Therefore, the energy consumption that is caused by the UE is preferably reduced by the handling of the UE by the base station. The first action includes actions that lead to a decrease of the QoS for the UE over a scenario in which the first action is not applied for the UE.

Preferably, the first action comprises one or more of the following: steering the UE to a specific frequency band, selecting a specific modulation and coding scheme for the UE, and selecting a specific number of MIMO layers for the UE. The specific frequency band, the specific modulation and coding scheme and/or the specific number of MIMO layers can be pre-defined and preferably derives from a regular frequency band, modulation and coding scheme and/or number of MIMO layers that is used when the first action is not applied for the UE.

Preferable, the message is transmitted to the UE via the RAN over non-access stratum (NAS) and/or radio resource control (RRC). As the message is transmitted to the UE, the UE itself can take actions to reduce an energy consumption, wherein this reduction of the energy consumption is triggered by the core network. In an example, this allows to reduce an energy consumption of the UEs of a wireless communication network in specific regions.

Preferably, the message is one of the following: a Configuration Update Command over NAS, a Registration Accept over NAS, a PDU Session Establishment Accept over NAS, a PDU Session Modification Command over NAS, or a RRC Reconfiguration message over RRC.

Preferably, the UE is performing a second action to reduce an energy consumption of the UE in response to receiving the message that is indicating that the energy efficiency accepted indica- tor is set for the UE. Therefore, the energy consumption that is caused by the UE can be reduced by the UE. The second action includes actions that lead to a decrease of the QoS for the UE when compared to a scenario in which the second action is not applied by the UE.

Preferably, the second action comprises one or more of the following: prevent handovers of the UE to WiFi, increase a duration of a sleep mode of the UE, and limit a network access that is performed via the RAN for an application on the UE. For example, the application is a messenger application and is limited to text messages without multimedia content to reduce a data amount that is to be transmitted to reduce the energy consumption.

Preferably, the UE is displaying an indicator in response to receiving the message that is indicating that the energy efficiency accepted indicator is set for the UE. For example an icon or text for indicating that the energy efficiency accepted indicator is set for the UE is displayed. This informs a user of the UE that actions are performed to reduce the energy consumption of the UE. In case this leads to a decreased QoS, this information will increase an acceptance level of the user of the UE.

Preferably, the core network is performing a third action to reduce an energy consumption for the UE in response to determining that the energy efficiency accepted indicator is set for the UE. For example, the core network is storing information in respect to an energy efficiency of network functions, for example an energy efficiency of a User Plane Function (UPF). The information in respect to the energy efficiency might indicate the amount or type of energy that is consumed by the network function. In an example, it might be indicated for the core network whether a network function is using green energy or not. In this case, the third action can comprise the action of selecting a UPF dependent on the amount or type of energy that is consumed that is used by the UPF to select a most energy efficient UPF for the UE. That is, a UPF can be selected, even if this UPF is very far away, which might lead to increased data latency.

A core network of a mobile communications network according to the invention is configured to determine whether an energy efficiency accepted indicator is set for a user equipment (UE) wherein the energy efficiency indicator is indicating whether energy saving functionalities should be applied; and to transmit a message to a radio access network (RAN), wherein the message is indicating that the energy efficiency accepted indicator is set for the UE, if it is determined that the energy efficiency accepted indicator is set for the UE. Preferably, the message is indicating that the energy efficiency accepted indicator is not set for the UE, if it is determined that the energy efficiency accepted indicator is not set for the UE.

Preferably, the core network is configured to determine whether the energy efficiency accepted indicator is set for the UE by fetching the energy efficiency accepted indicator from a Unified Data Registry (UDR) of the core network.

Preferably, the message is transmitted to a base station of the RAN or to the UE via the RAN.

The core network and the method allow a subscription or policy based energy efficiency control in RAN and transparency in the UE, communicated over NGAP and NAS.

A user equipment (UE) for a mobile communications network according to the invention is configured to receive a message from a core network that is transmitted to the UE via a radio access network (RAN), wherein the message is indicating that an energy efficiency accepted indicator is set for the UE, and perform an action to reduce an energy consumption of the UE in response to receiving the message that is indicating that the energy efficiency accepted indicator is set for the UE.

Preferably, the action comprises one or more of the following: prevent handovers of the UE to WiFi, increase a duration of a sleep mode of the UE, and limit a network access that is performed via the RAN for an application on the UE. The action that is performed by the UE is also referred to as second action.

A base station for a radio access network (RAN) of a mobile communications network according to the invention is configured to receive a message that is transmitted to the base station from a core network, wherein the message is indicating that an energy efficiency accepted indicator is set for a user equipment (UE), and perform an action to reduce an energy consumption for the UE in response to receiving the message that is indicating that the energy efficiency accepted indicator is set for the UE.

Preferably, the action comprises one or more of the following: steering the UE to a specific frequency band, selecting a specific modulation and coding scheme for the UE, and selecting a specific number of Ml MO layers for the UE. The action that is performed by the base station is also referred to as first action. A system for communications network according to the invention is configured to perform the method according to the invention.

Brief description of the drawings

Fig. 1 shows a wireless communications system comprising a core network according to an embodiment of the invention, fig. 2 shows a flow diagram of a method according to the embodiment of the invention, fig. 3 shows a user equipment according to the embodiment of the invention, fig. 4 shows details in respect to a first preferable communication flow in a communications network that is performed according to the embodiment of the invention, fig. 5 shows details in respect to a second preferable communication flow in a communications network that is performed according to the embodiment of the invention, fig. 6 shows a preferable structure of a user equipment according to the invention, and fig. 7 shows a preferable structure of a base station according to the invention.

Detailed

A wireless communications network 1 comprising a core network 2 according to an embodiment of the invention is depicted in figure 1 . The wireless communications network 1 comprises the core network 2, a radio access network (RAN) 3 and a User Equipment (UE) 4. The RAN 3 comprises a base station 5, for example an eNB. The wireless communications network 1 is configured to perform a method 10 for managing an energy usage in the mobile communications network. A flowchart of the method 10 is illustrated in figure 2.

In a first step 11 of the method 10, the core network 2 is determining whether an energy efficiency accepted indicator is set for the UE 4.

The energy efficiency accepted indicator is indicating whether energy savings should be applied for the UE 4 or not. That is, if the energy efficiency accepted indicator is set, energy saving measures are applied for the UE 4. If the energy efficiency accepted indicator is not set, the energy saving measures are not applied for the UE 4. Thus, the energy efficiency accepted indicator is indicating whether energy saving functionalities should be applied for the UE 4. The energy efficiency accepted indicator is a parameter that is set for the UE 4 by a subscription data provisioning system (SDPS) in a Unified Data Repository (UDR) of the core network 2. For example, the energy efficiency accepted indicator is a parameter that is set in an entry of the UDR that is logically linked to the UE 4. An entity of the core network 2 is fetching the energy efficiency accepted indicator from the UDR to determine whether the energy efficiency accepted indicator is set for the UE 4.

In a second step 12 of the method 10, the core network 2 is transmitting a message to the RAN 3, wherein the message is indicating that the energy efficiency accepted indicator is set for the UE, if it is determined that the energy efficiency accepted indicator is set for the UE. If it is determined that the energy efficiency accepted indicator is not set for the UE, the core network 2 is transmitting a message to the RAN 3, wherein the message is indicating that the energy efficiency accepted indicator is not set for the UE 4.

The message is sent to the RAN 3, wherein the final receiver of the message is the RAN 3 itself, in particular the base station 5 of the RAN 3. In addition or in the alternative, the final receiver of the message is the UE 4, wherein the message is transmitted via the RAN 3. Optionally, two separate messages are transmitted by the core network 2, wherein both messages are indicating whether the energy efficiency accepted indicator is set for the UE 4 and one message is sent to the RAN 3 as final receiver and one message is sent to the UE 4 as final receiver.

If the message that is indicating whether the energy efficiency accepted indicator is set for the UE is transmitted to base station 5 of the RAN 3, then the message is preferably transmitted over next generation application protocol (NGAP) or any alternative communication protocol for communication between the core network 2 and the base station 5 of the RAN 3. This is an established protocol for communication between the core network 2 and the RAN 3. It is preferable that the energy efficiency accepted indicator is transmitted in a message that is already known in NGAP by adding a dedicated field or bit for the energy efficiency accepted indicator. The message in NGAP that is used for transmitting the energy efficiency accepted indicator is preferably an Initial Context Setup Request, a UE Context Modification Request, a DL NAS Transport, a Handover Request, a Path Switch Request Acknowledge, a UE Context Resume Response, a Connection Establishment Indication, an AMF CP Relocation Indication, a UE Context Suspend Response, a UE Information Transfer, a PDU Session Resource Setup Request, a PDU Session Resources Modify Request, or a PDU Session Resource Modify Confirm. Once the message is received by the base station 5, the base station 5 is determining whether the energy efficiency accepted indicator is set or not. If it is determined that the energy efficiency accepted indicator is set, the RAN3, in particular the base station 3, is performing a first action 13 to reduce an energy consumption for the UE 4. With the first action, the RAN 3 applies certain rules to reduce the traffic related power consumption of the UE 4. In case of the base station 5 being aware that some user is accepting potentially reduced performance (e.g., increased latency), the base station 5 optionally applies implementation specific means to reduce the energy being used, even if this action has implications on the end-user QoE of the UE 4.

For example, the base station 5 is steering the UE 4 to a specific frequency band, wherein the specific frequency band is known to require less power for the UE (e.g. less transmit power). In another example, the base station 5 selects modulation and coding schemes and a number of Multiple-input/multiple-out (MIMO) layers that consume less energy, even if the transmission duration increases. Therefore, the first action can comprise the steps of selecting a specific modulation and coding scheme for the UE 4 and/or selecting a specific number of MIMO layers for the UE 4.

If it is determined by the base station 5 that the energy efficiency accepted indicator is not set, the first action 13 to reduce an energy consumption for the UE 4 is not performed in reaction to the received message.

If the message that is indicating whether the energy efficiency accepted indicator is set for the UE is transmitted to UE 4, then the message is preferably transmitted to the UE 4 via the RAN 3 over non-access stratum, NAS, and/or radio resource control, RRC. It is preferable that the energy efficiency accepted indicator is transmitted in a message that is already known to be used for a communication towards the UE 4, wherein a dedicated field or bit for the energy efficiency accepted indicator is added to the message. The message that is used for transmitting the energy efficiency accepted indicator to the UE 4 is preferably a Configuration Update Command, a Registration Accept, a PDU Session Establishment Accept, a PDU Session Modification Command, or a RRC Reconfiguration message over RRC.

Once the message is received by the UE 4, the UE 4 is determining whether the energy efficiency accepted indicator is set or not. If the energy efficiency accepted indicator is set, the UE 4 is performing a second action 14 to reduce an energy consumption for the UE 4. If it is determined by the UE 4 that the energy efficiency accepted indicator is not set, the second action 13 to reduce an energy consumption for the UE 4 is not performed in reaction to the received message.

With the second action, the UE 4 applies certain rules to reduce the traffic related power consumption of the UE 4. For example, the UE 4 prevent handovers to WiFi, even if performance is degraded due to this feature. In another example, the UE 4 is applying a longer sleep mode, i.e. , connects less frequently to the core network 2. In another example, the UE 4 allows certain applications and services only or without limits when energy efficiency is available, that is when the energy efficiency accepted indicator is set. In other words, the UE 4 limits a network access that is performed via the RAN for an application on the UE 4 in the energy efficiency accepted indicator is set. In another example, the UE 4 is transmitting a message to request a reduction of a video coding quality to a transmitter of video content. That is, the Application Client, here the UE 4, informs an application backend so that downlink video is proactively adapted at the source.

Optionally, the core network 2 and/or the RAN 3 are performing actions to increase an energy efficiency for the UE 4 if the energy efficiency accepted indicator is set. In this case, the energy efficiency accepted indicator is also an indicator for the UE 4 that is indicating if energy saving measures are applied by the core network 2 or the RAN 3. Therefore, the UE 4 is preferably limiting energy consuming network access to points in time when the energy efficiency accepted indicator is set. For example, text messages on the UE 4 are possible when the energy efficiency accepted indicator is set and video up- and download is only available if the energy efficiency accepted indicator is not set.

Preferably, the UE 4 is displaying an indicator 6 in response to receiving the message that is indicating that the energy efficiency accepted indicator is set for the UE 4. An exemplary indicator 6 is depicted in figure 3. This will make a user of the UE 4 aware that energy saving measures are currently applied and will increase an acceptance level for a decrease QoS.

Figure 4 is illustrating details in respect to a first preferable communication in the communications network 1.

During a configuration of subscription data, the SDPS is setting subscription data in the UDR in a subscription data transmission 101 , wherein the subscription data comprises the energy efficiency accepted indicator. During a following runtime process, the UE 4 is transmitting a registration request 102 to the RAN 3. The RAN 3 is forwarding the registration request 102 to an Access & Mobility Management Function (AMF) of the core network 2 by transmitting a forwarded registration request 103 to the AMF of the core network 2. The AMF will then transmit an identity request 104 to the UE 4 to which the UE 4 will reply with an identity response 105. Once the identity response 105 is received, the AMF performs s selection of an Authentication Server Function (AUSF).

During a following authentication and security process, the AMF is selecting a Unified Data Management (UDM) and is then performing a Nudm_UECM_registration 106 with the UDM. Then, the AMF is transmitting a Nudm_SDM_Get message 107 to the UDM to retrieve the UE's individual subscription data. The UDM is fetching 108 the subscription data including the energy efficiency accepted indicator from the UDR and is transmitting a subscription data response 109 that includes the energy efficiency accepted indicator to the AMF. Thus, the core network 3 is determining whether the energy efficiency accepted indicator is set for the UE 4.

The AMF is sending a registration accept message 110 to the RAN 3 in response to the registration request 103 that was transmitted from the RAN 3 to the AMF. The registration accept message 110 comprises the energy efficiency accepted indicator and is therefore indicating that the energy efficiency accepted indicator is set for the UE 4, if it was previously determined that the energy efficiency accepted indicator is set for the UE 4.

In response to receiving the registration accept message 110, the RAN 3 is transmitting a forwarded registration accept message 111 to the UE 4. The forwarded registration accept message 111 comprises the energy efficiency accepted indicator and is therefore indicating that the energy efficiency accepted indicator is set for the UE 4, if it was previously determined that the energy efficiency accepted indicator is set for the UE 4.

The registration accept message 110 is a NAS message and sent from the AMF to the UE via the RAN. The registration accept message 11 from AMF to RAN message is a DL NAS Transport. The Registration Accept message is encapsulated inside the DL NAS Transport.

In response to receiving the registration accept message 110, the RAN 3 is performing the first action 13 to reduce the energy consumption for the UE 4 if it is indicated that the energy efficiency accepted indicator is set for the UE 4 in the registration accept message 110. For example, the RAN 3 or a base station 5 of the RAN 4 is selecting a frequency band for the UE or is instructing the UE 4 to offload data by using a different radio access technology (RAT). In response to receiving the forwarded registration accept message 111 , the UE 4 is performing the second action 14 to reduce the energy consumption for the UE 4.

Figure 5 is illustrating details in respect to a second preferable communication in the communications network 1 .

During a configuration of subscription data, the SDPS is setting subscription data in the UDR in a subscription data transmission 201 , wherein the subscription data comprises the energy efficiency accepted indicator.

During a following runtime process, the UE 4 is transmitting a PDU Session Establishment Request 202 to an Access & Mobility Management Function (AMF) of the core network 2. The AMF is then performing a SMF discovery and selection by transmitting a NF_Discovery_Re- quest 203 to a network Repository Function (NRF) and by receiving a NF_Discovery_Result 204 from the NRF. The NF_Discovery_Result 204 is indicating a Session Management Function (SMF).

The AMF is then transmitting a Nsmf_PDUSession_CreateSMContext Request 205 to the SMF. Upon receiving the Nsmf_PDUSession_CreateSMContext Request 205, the SMF is transmitting a Nudm_SDM_Get message 206 to the UDM to retrieve the UE's individual subscription data. The UDM is fetching 207 the subscription data including the energy efficiency accepted indicator from the UDR and is transmitting a subscription data response 208 that includes the energy efficiency accepted indicator to the SMF. Thus, the core network 3 is determining whether the energy efficiency accepted indicator is set for the UE 4.

The SMF is transmitting a Nsmf_PDUSession_CreatedSMContext Response to the AMF after receiving the subscription data response 208, wherein the Nsmf_PDUSession_CreatedSMCon- text Response is a response to the previously sent Nsmf_PDUSession_CreateSMContext Request 205.

The SMF is then performing a UPF discovery and selection by transmitting a NF_Discovery_Re- quest for UPF 210 to the NRF and by receiving a NF_Discovery_Result for UPF 211 from the NRF. The NF_Discovery_Result for UPF 211 is indicating a User Plane Function (UPF). In response to receiving the NF_Discovery_Result for UPF 211 that is indicating the UPF, the SMF is performing a session establishment 212 with the indicated UPF. After the session establishment 212, the SMF is transmitting Nsmf_Communication_N1 N2Mes- sageTransmfer messages 213 to the AMF, wherein the Nsmf_Communication_N1 N2Mes- sageTransmfer messages 213 comprises the energy efficiency accepted indicator. In reply to receiving the Nsmf_Communication_N1 N2MessageTransmfer messages, the AMF is transmitting a N2_PDU_Session_Request message 214, which is a NGAP message that includes a NAS message that comprises the energy efficiency accepted indicator to the RAN 3. NAS messages are transparently transported via RAN. The RAN 3 will send a specific resource setup message 215 to the UE 4 and receive a PDU_Session_Establishment Accept message from the UE4 in response. The specific resource setup message 215 comprises the energy efficiency accepted indicator.

In response to receiving the N2_PDU_Session_Request message 214, the RAN 3 will perform the first action 13. In response to receiving specific resource setup message 215, the UE 4 will perform the second action 14.

The RAN 3 will further provide a N2_PDU_Session_Response message 216 to the AMF in response to the N2_PDU_Session_Request message 214 after setting up an N2_PDU_Sessio, which included transmitting the specific resource setup message 215.

In case the energy efficiency accepted indicator is transmitted via NGAP, the energy efficiency active indicator can be indicated as follows:

In case the energy efficiency accepted indicator is transmitted via NAS, the energy efficiency active indicator can be indication as a type 1 information element and can be indicated as follows:

8 7 6 5 4 3 2 1

Energy efficiency accepted indication information element

Energy efficiency accepted indication information element

In case the energy efficiency accepted indicator is transmitted via NAS (3GPP TS 24.501) and messages will use new IE, the message might be defined as follows:

Message type: REGISTRATION ACCEPT

Significance: dual

Direction: network to UE

REGISTRATION ACCEPT message content:

Same IE and principle can be applied to the following NAS messages as well:

• Configuration Update Command

• PDU Session Establishment Accept • PDU Session Modification Command

In case the energy efficiency accepted indicator is transmitted via NGAP (3GPP TS 38.413) and messages will use new IE, the message might be defined as follows: INITIAL CONTEXT SETUP REQUEST

This message is sent by the AMF to request the setup of a UE context.

Direction: AMF to NG-RAN node

Same IE and principle apply to the following NGAP messages as well:

• UE Context Modification Request (Mobility related)

• DL NAS Transport (Mobility and Session related)

Figure 6 is showing a configuration of the UE 4. The UE 4 comprises a CPU 21 , a memory 22, a transceiver 23 and a display 24. The transceiver 4 of the UE 24 is configured to communicate with the mobile communications network 1. The memory 22 comprises information that, when executed by the CPU 21 , leads to a receiving of a message by the CPU 21 via the transceiver 23 from the core network 2 that is transmitted to the UE 4 via the RAN 3, wherein the message is indicating that an energy efficiency accepted indicator is set for the UE 4. The memory 22 comprises information that, when executed by the CPU 2, leads to the CPU 21 performing an action 14 to reduce an energy consumption of the UE 4 in response to receiving the message that is indicating that the energy efficiency accepted indicator is set for the UE 4. The information is preferably instructing the CPU 21 to display an indicator 6 on the display 24 in response to receiving the message that is indicating that the energy efficiency accepted indicator is set for the UE 4.

Figure 7 is showing a configuration of the base station 3. The base station 3 comprises a CPU 31 , a memory 32, a transceiver 33 and a display 34. The transceiver 34 of the base station 3 is configured to communicate with the mobile communications network 1. The memory 32 comprises information that, when executed by the CPU 31, leads to a receiving of a message by the CPU 31 via the transceiver 33 from the core network 2, wherein the message is indicating that an energy efficiency accepted indicator is set for the UE 4. The memory 32 further comprises information that, when executed by the CPU 31, leads to the CPU 31 performing an action 13 to reduce an energy consumption for the UE 4 in response to receiving the message that is indicating that the energy efficiency accepted indicator is set for the UE 4.

Claims

1. Method (10) for a mobile communications network (1), the method comprising: determining (11), by a core network (2), whether an energy efficiency accepted indicator is set for a user equipment, UE (4), wherein the energy efficiency accepted indicator is indicating whether energy saving functionalities should be applied for the UE (4); and transmitting (12), by the core network (2), a message to a radio access network, RAN (3), wherein the message is indicating that the energy efficiency accepted indicator is set for the UE, if it is determined that the energy efficiency accepted indicator is set for the UE.

2. The method (10) according to claim 1 , wherein the message is indicating that the energy efficiency accepted indicator is not set for the UE (4), if it is determined that the energy efficiency accepted indicator is not set for the UE (4).

3. The method (10) according to any one of the previous claims, wherein the Determining whether the energy efficiency accepted indicator is set for the UE (4) comprises fetching the energy efficiency accepted indicator from a Unified Data Repository, UDR, of the core network.

4. The method (10) according to any one of the previous claims, wherein the message is transmitted to a base station (5) of the RAN (3).

5. The method (10) according to claim 4, wherein the message is transmitted to the base station (5) of the RAN (3) over next generation application protocol, NGAP, wherein the message is preferably one of the following:

• an Initial Context Setup Request,

• a UE Context Modification Request,

• a DL NAS Transport,

• a Handover Request,

• a Path Switch Request Acknowledge,

• a UE Context Resume Response,

• a Connection Establishment Indication, • an AMF CP Relocation Indication,

• a UE Context Suspend Response,

• a UE Information Transfer,

• a PDU Session Resource Setup Request,

• a PDU Session Resources Modify Request, or

• a PDU Session Resource Modify Confirm.

6. The method (10) according to any one of claims 4 and 5, wherein the base station (3) is performing a first action (13) to reduce an energy consumption for the UE (4) in response to receiving the message that is indicating that the energy efficiency accepted indicator is set for the UE (4).

7. The method (10) according to claim 6, wherein the first action (13) to reduce the energy consumption for the UE (4) that is performed by the base station comprises one or more of the following:

- steering the UE (4) to a specific frequency band;

- selecting a specific modulation and coding scheme for the UE (4);

- selecting a specific number of MIMO layers for the UE (4).

8. The method (10) according to any one of the previous claims, wherein the message is transmitted to the UE (4) via the RAN (3) over non-access stratum, NAS, and/or radio resource control, RRC.

9. The method (10) according to claim 8, wherein the message is one of the following:

• a Configuration Update Command over NAS,

• a Registration Accept over NAS,

• a PDU Session Establishment Accept over NAS,

• a PDU Session Modification Command over NAS, or

• a RRC Reconfiguration message over RRC.

10. The method (10) according to any one of claims 8 and 9, wherein the UE (4) is performing a second action (14) to reduce an energy consumption of the UE (4) in response to receiving the message that is indicating that the energy efficiency accepted indicator is set for the UE (4).

11. The method (10) according to claim 10, wherein the second action (14) to reduce the energy consumption that is performed by the UE (4) comprises one or more of the following:

• prevent handovers of the UE (4) to WiFi,

• increase a duration of a sleep mode of the UE (4), and

• limit a network access that is performed via the RAN (3) for an application on the UE (4).

12. The method according to any one of claims 8 to 11 , wherein the UE (4) is displaying an indicator (6) in response to receiving the message that is indicating that the energy efficiency accepted indicator is set for the UE (4).

13. The method (10) according to any one of the previous claims, wherein the core network (2) is performing a third action (13) to reduce an energy consumption for the UE (4) in response to determining (11) that the energy efficiency accepted indicator is set for the UE (4).

14. Core Network (2) of a mobile communications network (1), the core network (2) being configured to: determine whether an energy efficiency accepted indicator is set for a user equipment, UE (4), wherein the energy efficiency indicator is indicating whether energy saving functionalities should be applied; and transmit a message to a radio access network, RAN (3), wherein the message is indicating that the energy efficiency accepted indicator is set for the UE (4), if it is determined that the energy efficiency accepted indicator is set for the UE (4).

15. The core network (2) according to claim 14, wherein the core network (2) is configured to determine whether the energy efficiency accepted indicator is set for the UE (4) by fetching the energy efficiency accepted indicator from a Unified Data Registry, UDR, of the core network (2).

16. User Equipment, UE (4), for a mobile communications network (1), the UE (2) being configured to: receive a message from a core network (2) that is transmitted to the UE (4) via a radio access network, RAN (3), wherein the message is indicating that an energy efficiency accepted indicator is set for the UE (4); and perform an action (14) to reduce an energy consumption of the UE (4) in response to receiving the message that is indicating that the energy efficiency accepted indicator is set for the UE (4).

17. Base station (5) for a radio access network, RAN (3), of a mobile communications network

(1), the base station (5) being configured to: receive a message that is transmitted to the base station (5) from a core network (2), wherein the message is indicating that an energy efficiency accepted indicator is set for a user equipment, UE (4); and perform an action (13) to reduce an energy consumption for the UE (4) in response to receiving the message that is indicating that the energy efficiency accepted indicator is set for the UE (4).

18. System for a communications network (1), characterized in that the system is configured to perform the method according to any one of claims 1 to 13.