Patent Description:
The radio access network node (such as an evolved NodeB; eNB) could be configured to control a dual connectivity radio connection that uses a combination of a fourth generation (<NUM>) radio access network and a fifth generation (<NUM>) radio access network with the <NUM> radio access network as a secondary radio access technology (RAT) using the evolved packet core (EPC) network in a Non-Standalone (NSA) configuration when the sG-capable UEs are simultaneously associated both with eNB and a radio access network node (such as a gNodeB; gNB) in the <NUM> radio access network.

When it is possible to use a secondary RAT in conjunction with a <NUM> radio access network, the mobile network operator might activate Secondary RAT Usage Data Reporting pertaining to how much data the UE has consumed using the secondary RAT. The activation of the Secondary RAT Usage Data Reporting might occur separately from Data Volume Reporting of New Radio (NR) and Unlicensed Spectrum. Data volumes might be reported for the secondary RAT on a per Evolved Packet System (EPS) bearer basis and per time interval.

Change Request <NPL>" describes the introduction of support for secondary RAT reporting in 3GPP's TS <NUM>.

<CIT> concerns network selection by a mobile device that enables a network selection based, at least in part, on a network access policy that indicates use of a radio access technology (RAT) based on one or more network characteristics. The network access policy may be selectively applied based on one or more predetermined conditions, such as a time of day, mobile device location, RAT access cost, roaming status, subscription profile, and/or data usage, for example, In some examples, when the network access policy is applied, the mobile device may be configured to select from among a number of access nodes that may operate using different RATs, such as cellular access node(s) or Wireless Local Area Network (WLAN) access node(s). Communications may be established with a selected access node based at least in part on network conditions such as available bandwidth for an access node.

3GPP Change Request<NPL>" also concerns the reporting of data volume of secondary RAT to the <NUM> core in 3GPP's TS <NUM>.

However, it is currently cumbersome to determine whether to apply any restrictions to further use of the secondary RAT for a UE or not.

Hence, there is a need for better handling the use of a secondary RAT for a UE.

According to a first aspect there is presented a method for handling secondary RAT data usage for a UE. The method is performed by a mobility node. The method comprises obtaining, from a network node, an indication of data usage for the UE using the secondary RAT. The method comprises forwarding the indication towards a policy node. The method comprises obtaining a policy decision originating from the policy node. The policy decision is based on the indication of data usage. The method comprises performing an action based on the policy decision.

According to a second aspect there is presented a mobility node for handling secondary RAT data usage for a UE. The mobility node comprises processing circuitry. The processing circuitry is configured to cause the mobility node to obtain, from a network node, an indication of data usage for the UE using the secondary RAT. The processing circuitry is configured to cause the mobility node to forward the indication towards a policy node. The processing circuitry is configured to cause the mobility node to obtain a policy decision originating from the policy node. The policy decision is based on the indication of data usage. The processing circuitry is configured to cause the mobility node to perform an action based on the policy decision.

According to a third aspect there is presented a computer program for handling secondary RAT data usage for a UE. The computer program comprises computer program code which, when run on processing circuitry of a mobility node, causes the mobility node to perform a method according to the first aspect.

According to a fourth aspect there is presented a method for handling secondary RAT data usage for a UE. The method is performed by a policy node. The method comprises obtaining, from a mobility node, an indication of data usage for the UE using the secondary RAT. The method comprises determining a policy decision for the UE based on the indication of data usage. The method comprises providing the policy decision towards the mobility node.

According to a fifth aspect there is presented a policy node for handling secondary RAT data usage for a UE. The policy node comprises processing circuitry. The processing circuitry is configured to cause the policy node to obtain, from a mobility node, an indication of data usage for the UE using the secondary RAT. The processing circuitry is configured to cause the policy node to determine a policy decision for the UE based on the indication of data usage. The processing circuitry is configured to cause the policy node to provide the policy decision towards the mobility node.

According to an sixth aspect there is presented a computer program for handling secondary RAT data usage for a UE, the computer program comprising computer program code which, when run on processing circuitry of a policy node, causes the policy node to perform a method according to the fourth aspect.

According to a seventh aspect there is presented a computer program product comprising a computer program according to at least one of the third aspect and the sixth aspect and a computer readable storage medium on which the computer program is stored. The computer readable storage medium could be a non-transitory computer readable storage medium.

According to an eight aspect there is presented a communication network. The communication network comprises a mobility node according to the second aspect and a policy node according the fifth aspect.

Advantageously these methods, this mobility node, this policy node, these computer programs, this computer program, and this communication network provide efficient handling of secondary RAT data usage for a UE. Advantageously this enables efficient policy decisions to be made.

Advantageously these methods, this mobility node, this policy node, these computer programs, this computer program, and this communication network can be used to determine whether to apply any restrictions to further use of the secondary RAT for a UE or not.

Advantageously these methods, this mobility node, this policy node, these computer programs, this computer program, and this communication network enable dynamic policy decisions to be determined based on Secondary RAT Usage Data Reporting and enables flexible adaptation and differentiation of network access, quality of services, etc. for the UE depending on current network conditions, subscriber category subscription and data usage in the secondary RAT.

Advantageously these methods, this mobility node, this policy node, these computer programs, this computer program, and this communication network enable control over the accumulated data consumed by the UE during a period over NR as secondary RAT and enables appropriate actions, such as access control, notifications, quality of service modification or throttling, charging control, session termination, etc., to be taken based on the data usage for the UE using the secondary RAT.

<FIG> is a schematic diagram illustrating a communications network <NUM> where embodiments presented herein can be applied. The communications network <NUM> comprises a first radio access network (RAN) 110a comprising a network node 120a for providing network access to UEs 130a, 130b, 130c using a first radio access technology. The communications network <NUM> further comprises a second radio access network 110b comprising a network node 120b for providing network access to UEs 130a, 130b, 130c using a second radio access technology. In case the first radio access technology is <NUM> radio access, the second radio access technology could be <NUM> radio access. Hence, the network node 120a could provide <NUM> network access to UEs 130a, 130b, 130cand the network node 120b could provide <NUM> network access to UEs 130a, 130b, 130c. Hence, the first radio access network 110a could be a <NUM> radio access network and the second radio access network 110b could be a <NUM> radio access network.

The network node 120a could be an eNB and the network node 120b could be a gNB. Examples of UEs 130a, 130b, 130c are wireless devices, mobile stations, mobile phones, handsets, wireless local loop phones, smartphones, laptop computers, tablet computers, network equipped sensors, network equipped vehicles, and so-called Internet of Things devices. The radio access networks 110a, 110b are operatively connected to a core network (CN) <NUM>. The core network <NUM> comprises at least one serving gateway (SGW) <NUM>, at least packet data network gateway (PGW) <NUM>, a HSS <NUM>, a mobility node <NUM>, and a policy node <NUM> having at least those operable connections and interfaces as illustrated in <FIG>. The core network <NUM> is in turn operatively connected to a packet data network (PDN) <NUM>. The UEs 130a, 130b, 130care thereby enabled to, via the network nodes 120a, 120b, access services of, and exchange data with, the packet data network <NUM>. In some aspects the functionality of the mobility node <NUM> is implemented in a Mobility Management Entity (MME) or similar. In some aspects the functionality of the policy node <NUM> is implemented in a Policy and Charging Rules Function (PCRF) or similar.

In the illustrative example of <FIG> the <NUM> radio access network 110b can be regarded as a secondary RAT using the core network <NUM> in an NSA configuration.

As disclosed above there is a need for better handling the use of a secondary RAT for a UE 130a, 130b, 130c. In this respect, the policy node <NUM> is the functional element that encompasses policy control decision and flow based charging control functionalities. It provides network and gating control, and manages the flow based charging. The policy node <NUM> could be configured to instruct the mobility node <NUM> to select the PGW <NUM> for a UE 130a, 130b, 130c when the UE 130a, 130b, 130c attaches to the radio access network 110a. The policy node <NUM> could further be configured to provide the mobility node <NUM> with RAT or Frequency Selection Priority (RFSP) and a list of event-triggers for notifications for the UE 130a, 130b, 130c.

In general terms, the policy node <NUM> aggregates information to and from the radio access network 110a, operational support systems, and other sources (such as portals) in real time, supporting the creation of rules and then automatically makes policy decisions for each UE 130a, 130b, 130c. However, currently, usage data reported over NR as secondary RAT is not considered for policy decisions. The embodiments disclosed herein therefore provide mechanisms to pass the Secondary RAT Usage Data Reporting from the mobility node <NUM> towards the policy node <NUM> (either directly or via the PGW <NUM>) in order for the PRF node <NUM> to make dynamic policy decisions based on the Secondary RAT Usage Data Reporting. The embodiments disclosed herein in particular relate to mechanisms for handling secondary RAT data usage for a UE 130a, 130b, 130c. In order to obtain such mechanisms there is provided a mobility node <NUM>, a method performed by the mobility node <NUM>, a computer program product comprising code, for example in the form of a computer program, that when run on processing circuitry of the mobility node <NUM>, causes the mobility node <NUM> to perform the method. In order to obtain such mechanisms there is further provided a policy node <NUM>, a method performed by the policy node <NUM>, and a computer program product comprising code, for example in the form of a computer program, that when run on processing circuitry of the policy node <NUM>, causes the policy node <NUM> to perform the method.

Reference is now made to <FIG> illustrating a method for handling secondary RAT data usage for a UE 130a, 130b, 130cas performed by the mobility node <NUM> according to an embodiment.

As noted above, the network node 120a might indicate data usage for the UE 130a, 130b, 130c using the secondary RAT. Hence, the mobility node <NUM> is configured to perform step S102:
S102: The mobility node <NUM> obtains, from a network node 120a, an indication of data usage for the UE 130a, 130b, 130c using the secondary RAT.

In this respect, the indication of data usage might be in the form of Secondary RAT usage reporting. The indication of data usage might be provided using S1 signalling messages which are either at the UE level (e.g. Path Switch Request, etc.), or at bearer level (e.g. E-RAB modification indication, Deactivate bearer response, etc.). E-RAB is short for E-UTRAN Radio Access Bearer, where E-LTTRAN is short for Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access.

Since a policy decision for the UE 130a, 130b, 130c is to be determined by the policy node <NUM>, the indication is forwarded towards the policy node <NUM>. Thus, the mobility node <NUM> is configured to perform step S106:
S106: The mobility node <NUM> forwards the indication towards the policy node <NUM>.

As will be further disclosed below, once the policy node <NUM> has determined a policy decision for the UE 130a, the policy decision is provided towards the mobility node <NUM>. In particular, the mobility node <NUM> is configured to perform step S108:
S108: The mobility node <NUM> obtains a policy decision originating from the policy node <NUM>. The policy decision is based on the indication of data usage.

The mobility node <NUM> then acts according to the policy decision. Thus, the mobility node <NUM> is configured to perform step S110:
S110: The mobility node <NUM> performs an action based on the policy decision.

Embodiments relating to further details of handling secondary RAT data usage for a UE 130a, 130b, 130cas performed by the mobility node <NUM> will now be disclosed.

There may be different ways for the UE 130a, 130b, 130c to access the secondary RAT and thus to consume data using the secondary RAT. Particularly, according to an embodiment, the UE 130a, 130b, 130c supports dual connectivity to a <NUM> radio access network 110a and a <NUM> radio access network 110b, the secondary RAT data usage pertains to data usage of the UE 130a, 130b, 130c in the <NUM> radio access network 110b.

There could be different ways to trigger the Secondary RAT Usage Data Reporting. In some aspects the mobility node <NUM> in step S106 autonomously forwards the indication towards the policy node <NUM>. As will be further disclosed below, in other aspects the Secondary RAT Usage Data Reporting is activated by event triggers. Particularly, according to an embodiment, the mobility node <NUM> is configured to perform (optional) step S104:
S104: The mobility node <NUM> obtains an event trigger from the policy node <NUM> for forwarding the indication, and the indication is in step S106 forwarded in response thereto (i.e., in response to the mobility node <NUM> having obtained the event trigger in step S104).

There could be different types of indications of data usage that the mobility node <NUM> obtains in step S102. The data usage could relate to uplink and/or downlink data for the UE 130a, 130b, 130c using the secondary RAT. The data usage could relate to over which period of time the data was consumed using the secondary RAT. The data usage could relate to over how long period of time the data was consumed using the secondary RAT. Particularly, according to an embodiment, the indication of data usage specifies the amount of uplink and/or downlink data usage using the secondary RAT over a period of time, and/or amount of time during which the UE 130a, 130b, 130c has consumed data using the secondary RAT.

There may be different ways for the MME <NUM> to forward the indications in step S106. Particularly, according to an embodiment, the indication is forwarded in a Credit Control Request (CCR) message. In more detail, the CCR message as sent from the mobility node <NUM> towards the policy node <NUM> could have the following structure to support Secondary RAT data usage reporting from the mobility node <NUM>:
<CC-Request> ::= < Diameter Header: <NUM>, REQ, PXY >
[. ]
[ Secondary RAT Usage Report List ].

Here, Secondary RAT Usage Report List is an Attribute-Value Pair (AVP) that specifies the Secondary RAT Usage Report IE and might specify the Secondary RAT Type, for example, unlicensed or New Radio, and the data usage count for uplink and downlink and/or start and end timestamps for data usage using the Secondary RAT. A part of the reporting is also a notification of data usage using NR access as secondary RAT in an NSA configuration since data usage using NR access indeed takes place when uplink or downlink data usage is reported for the secondary RAT since the secondary RAT includes NR access.

There may be different ways for the mobility node <NUM> to obtain the policy decision in step S108. Particularly, according to an embodiment, the policy decision is obtained in a Credit Control Answer (CCA) message.

There could be different ways for the mobility node <NUM> and the policy node <NUM> to communicate.

In deployments in which there is a binding between Gx/Rx/Sy/Sd sessions and an Smp session, the communication between the mobility node <NUM> and the policy node <NUM> relating to the Secondary RAT Usage Data Reporting could occur over the Gx interface. Particularly, according to an embodiment, the indication is forwarded towards the policy node <NUM>, and the policy decision is received from the policy node <NUM>, via at least one PGW <NUM>. The Secondary RAT Usage Data Reporting could thus occur over the Gx interface between the PGW <NUM> and the policy node <NUM> (where the mobility node <NUM> forwards the Secondary RAT Usage Data Reporting to the SGW <NUM> that in turns forwards it to the PGW <NUM> that in turns forwards it to the policy node <NUM>).

In deployments in which there is not any binding between Gx/Rx/Sy/Sd sessions and an Smp session, the communication between the mobility node <NUM> and the policy node <NUM> relating to the Secondary RAT Usage Data Reporting could occur over the Diameter Smp interface. Thus, in some aspects the mobility node <NUM> and the policy node <NUM> communicate over a Diameter Smp interface. Particularly, according to an embodiment, the indication is forwarded (as in step S106) and the policy decision is obtained (as in step s108) over a Diameter Smp interface between the mobility node <NUM> and the policy node <NUM>.

If the policy decision implies, for instance, access restriction to Dual Connectivity with NR (DCNR), then the mobility node <NUM> needs to forward this information to the network node 120a. That is, according to an embodiment, performing the action involves the mobility node <NUM> to forward the policy decision towards the network node 120a.

Reference is now made to <FIG> illustrating a method for handling secondary RAT data usage for a UE 130a, 130b, 130cas performed by the policy node <NUM> according to an embodiment.

As disclosed above, the mobility node <NUM> forwards the indication of data usage for the UE 130a, 130b, 130c using the secondary RAT towards the policy node <NUM>. Hence, the policy node <NUM> is configured to perform step S204:
S204: The policy node <NUM> obtains, from the mobility node <NUM>, an indication of data usage for the UE 130a, 130b, 130c using the secondary RAT.

A dynamic policy decision is then made by the policy node <NUM>. Particularly, the policy node <NUM> is configured to perform step S206:
S206: The policy node <NUM> determines a policy decision for the UE 130a, 130b, 130cbased on the indication of data usage.

In general terms, one policy decision is determined per individual UE 130a, 130b, <NUM>. The policy decision is then forwarded towards the mobility node <NUM>. Thus, the policy node <NUM> is configured to perform step S208:
S208: The policy node <NUM> provides the policy decision towards the mobility node <NUM>. As will be disclosed below, the policy decision might either be provided to the mobility node <NUM> over a direct interface between the policy node <NUM> and the mobility node <NUM> or provided to the mobility node <NUM> via the PGW <NUM> and the SGW150.

Embodiments relating to further details of handling secondary RAT data usage for a UE 130a, 130b, 130c as performed by the policy node <NUM> will now be disclosed.

As disclosed above, according to an embodiment the indication of data usage specifies the amount of uplink and/or downlink data usage using the secondary RAT over a period of time, and/or amount of time during which the UE 130a, 130b, 130c has consumed data using the secondary RAT. Any, all, or a subset of these parameters could thus be taken into account when determining the policy decision.

As disclosed above, according to an embodiment, the UE 130a, 130b, 130c supports dual connectivity to a <NUM> radio access network 110a and a <NUM> radio access network 110b, and the secondary RAT data usage pertains to data usage of the UE 130a, 130b, 130c in the <NUM> radio access network 110b.

In some aspects the Secondary RAT Usage Data Reporting is activated by event triggers sent by the policy node <NUM> towards the mobility node <NUM> (either directly or via the PGW <NUM> and SGW <NUM>). Particularly, according to an embodiment the policy node <NUM> is configured to perform (optional) step S202:
S202: The policy node <NUM> provides an event trigger towards the mobility node <NUM> for obtaining the indication, and the indication is obtained (as in step S104) in response thereto (i.e., in response to the policy node <NUM> having provided the event trigger in step S202). The event trigger might be included in a CCA message (such as in a CCA-I message (I for Initial)) in order for the policy node <NUM> to subscribe to Secondary RAT Usage events from the mobility node <NUM>. In more detail, the CCA message as sent from the policy node <NUM> towards the mobility node <NUM> could have the following structure:
<CC-Answer> ::= < Diameter Header: <NUM>, PXY >
[. ]
[ Event-trigger ].

Here, Event-trigger is an AVP that indicates that the policy node <NUM> requests to subscribe to Secondary RAT Usage events from the mobility node <NUM>.

There could be different policy decisions that are determined in step <NUM>.

The policy decision could pertain to any of RAT/frequency selection priority (RFSP) selection, NR access control as secondary RAT in an NSA configuration, and Quality of Service (QoS) modification or service access control, or any combination thereof. For example, the policy decisions could involve whether to restrict or allow NR access control as a secondary RAT using EPC in an NSA configuration.

In addition to forwarding the policy decision to the mobility node <NUM>, the PGW <NUM> might implement part of the policy decision itself (e.g. to throttle the traffic or to perform access control, etc.) based on the data usage in secondary RAT reported by the mobility node <NUM> to the policy node <NUM>. In this respect, the information about data usage using the secondary RAT can by the policy node <NUM> be used when determining policies for the UE 130a, 130b, 130c.

In some aspects, the policy decision involves RFSP selection for the UE 130a, 130b, 130c. Particularly, according to an embodiment the policy node <NUM> is configured to perform (optional) step S206a as part of determining the policy decision in step S206:
S206a: The policy node <NUM> determines whether to allow or restrict support for RFSP for the UE 130a, 130b, 130c.

In this respect, if a UE 130a, 130b, 130c surpasses a configured threshold of data usage on the secondary RAT the policy node <NUM> might decide whether to allow or restrict support for RFSP, which is used to apply specific Radio Resource Management strategies for the UE 130a, 130b, <NUM>. The policy node <NUM> might provide different RFSP identities when the data usage is below and above the configured threshold. This can be done in the policy node <NUM> via configuration of policies to determine the RFSP using the data usage in the secondary RAT as part of the input data for the policy decision.

In some aspects, the policy decision involves NR access control for the UE 130a, 130b, 130c. Particularly, according to an embodiment the policy node <NUM> is configured to perform (optional) step S206b as part of determining the policy decision in step S206:
S206b: The policy node <NUM> determines whether to, for the UE 130a, 130b, <NUM>, allow or restrict continued consumption of data using the secondary RAT. In some aspects, the policy decision involves a possible QoS modification for the UE 130a, 130b, 130c.

In this respect, if a UE 130a, 130b, 130c surpasses a configured threshold of data usage on the secondary RAT the policy node <NUM> might decide to disallow the traffic on the secondary RAT. In this way, the policy node <NUM> might allow data usage on the secondary RAT only when the data usage is below the configured threshold. This can be done in the policy node <NUM> via configuration of policies to allow or disallow the use of the secondary RAT using the data usage in the secondary RAT as part of the input data for the policy decision.

Particularly, according to an embodiment the policy node <NUM> is configured to perform (optional) step S206c as part of determining the policy decision in step S206:
S206c: The policy node <NUM> determines whether to, for the UE 130a, 130b, 130c, modify QoS or not.

In this respect, if a UE 130a, 130b, 130c surpasses a configured threshold of data usage on the secondary RAT a different QoS profile can be applied that reduces the priority of the traffic for the UE 130a, 130b, 130c or handles the traffic for the UE 130a, 130b, 130c in a best effort way. In this way, the policy node <NUM> can apply different QoS profiles where, for example, the bandwidth is guaranteed when the data usage is below the configured threshold but is handled in a best effort mode when the data usage is above the threshold. This can be done in the policy node <NUM> via configuration of policies to apply different QoS profiles using the data usage in the secondary RAT as part of the input data for the policy decision.

In cases where step S206c is performed, the policy decision is sent towards the mobility node <NUM> via the PGW <NUM>.

In some aspects, the policy decision further depends on the subscription category of the UE 130a, 130b, 130c. Particularly, according to an embodiment, the UE 130a, 130b, 130c is associated with a subscriber category, and the policy decision further is determined based on the subscriber category. The subscriber category might thus be taken into consideration when determining the policy decision according to any of steps S206, S206a, S206b, and S206c.

There might be different ways for policy node <NUM> to obtain the indication of data usage from the mobility node <NUM> in step S204. As above, according to an embodiment, the indication is obtained in CCR message.

There might be different ways for policy node <NUM> to provide the policy decision towards the mobility node <NUM> in step S208. As above, according to an embodiment, the policy decision is provided in a CCA message.

As above, in some aspects the mobility node <NUM> and the policy node <NUM> communicate via a PGW <NUM> and thus in some aspects the indication is obtained (as in step S204) from the mobility node <NUM> and the policy decision is provided (as in step S208) towards the mobility node <NUM> via the PGW <NUM> and the SGW <NUM>.

As above, in some aspects the mobility node <NUM> and the policy node <NUM> communicate via the PGW <NUM> and the SGW <NUM>. Particularly, according to an embodiment, the indication is obtained from the mobility node <NUM>, and wherein the policy decision is provided towards the mobility node <NUM>, via at least one packet gateway, PGW <NUM>. In this case, the indication and the policy decision are sent over the Gx interface.

As above, in some aspects the mobility node <NUM> and the policy node <NUM> communicate over a Diameter Smp interface. Particularly, according to an embodiment, the indication is obtained (as in step S204) and the policy decision is provided (as in step S208) over a Diameter Smp interface between the policy node <NUM> and the mobility node <NUM>.

A first particular embodiment for handling secondary RAT data usage for a UE 130a, 130b, 130cbased on at least some of the above disclosed embodiments will now be disclosed in detail with reference to the signalling diagram of <FIG>. In this embodiment the mobility node <NUM> and the policy node <NUM> communicate directly with each other, such as over the Diameter Smp interface.

S301: The network node 120a sends a Secondary RAT Usage Report that indicate data usage for the UE 130a, 130b, 130c using the secondary RAT. The mobility node <NUM> thereby obtains, from the network node 120a, an indication of data usage for the UE 130a, 130b, 130c using the secondary RAT.

S302: The mobility node <NUM> sends a CCR message comprising the Secondary RAT Usage Report for the event trigger Usage reporting to the policy node <NUM>. The mobility node <NUM> thereby forwards the indication towards the policy node <NUM>. It is here assumed that a previous exchange of CCR-I and CCA-I (I for Initial) messages has occurred between the policy node <NUM> and the mobility node <NUM> where the policy node <NUM> has sent the event trigger for Usage Reporting to the mobility node <NUM>.

S303: The policy node <NUM> determines a policy decision for the UE 130a, 130b, 130c based on the indication of data usage.

S304: The policy node <NUM> sends a CCA message comprising the policy decision and an event trigger for continued subscription of Secondary RAT Usage Reports to the mobility node <NUM>. The policy node <NUM> thereby provides the policy decision towards the mobility node <NUM> and provides an event trigger towards the mobility node <NUM> for obtaining further indications of data usage for the UE 130a, 130b, 130c using the secondary RAT.

A second particular embodiment for handling secondary RAT data usage for a UE 130a, 130b, 130c based on at least some of the above disclosed embodiments will now be disclosed in detail with reference to the signalling diagram of <FIG>. In this embodiment the mobility node <NUM> and the policy node <NUM> communicate with each other via the SGW <NUM> and the PGW <NUM>, such as over the Gx interface.

S401: The network node 120a sends a Secondary RAT Usage Report that indicate data usage for the UE 130a, 130b, 130c using the secondary RAT. The mobility node <NUM> thereby obtains, from the network node 120a, an indication of data usage for the UE 130a, 130b, 130c using the secondary RAT.

S402: The mobility node <NUM> sends a change notification message to the SGW <NUM>, where the change notification message comprises the indication of data usage for the UE 130a, 130b, 130c using the secondary RAT.

S403: The SGW <NUM> forwards the change notification message to the PGW <NUM>.

S404: The PGW <NUM> sends a CCR message to the PCR node <NUM>, where the CCR message comprises the indication of data usage for the UE 130a, 130b, 130c using the secondary RAT. The policy node <NUM> thereby obtains the indication of data usage for the UE 130a, 130b, 130c using the secondary RAT as originating from the mobility node <NUM> via the SGW <NUM> and the PGW <NUM>. It is here assumed that a previous exchange of CCR-I and CCA-I (I for Initial) messages has occurred between the policy node <NUM> and the mobility node <NUM> where the policy node <NUM> has sent the event trigger for Usage Reporting to the mobility node <NUM>.

S405: The policy node <NUM> determines a policy decision for the UE 130a, 130b, 130c based on the indication of data usage.

S406: The policy node <NUM> sends a CCA message comprising the policy decision and an event trigger for continued subscription of Secondary RAT Usage Reports to the PGW <NUM>. The policy node <NUM> thereby provides the policy decision towards the mobility node <NUM> and provides an event trigger towards the mobility node <NUM> for obtaining further indications of data usage for the UE 130a, 130b, 130c using the secondary RAT.

S407: The PGW <NUM> sends a change notification acknowledgement (Ack) message to the SGW <NUM> comprising the policy decision and an event trigger for continued subscription of Secondary RAT Usage Reports.

S408: The SGW <NUM> forwards the change notification acknowledgement message to the mobility node <NUM>. The mobility node <NUM> thereby obtains the policy decision and the event trigger as originating from the policy node <NUM>.

<FIG> schematically illustrates, in terms of a number of functional units, the components of a mobility node <NUM> according to an embodiment. Processing circuitry <NUM> is provided using any combination of one or more of a suitable central processing unit (CPU), multiprocessor, microcontroller, digital signal processor (DSP), etc., capable of executing software instructions stored in a computer program product 1010a (as in <FIG>), e.g. in the form of a storage medium <NUM>. The processing circuitry <NUM> may further be provided as at least one application specific integrated circuit (ASIC), or field programmable gate array (FPGA).

Particularly, the processing circuitry <NUM> is configured to cause the mobility node <NUM> to perform a set of operations, or steps, as disclosed above. For example, the storage medium <NUM> may store the set of operations, and the processing circuitry <NUM> may be configured to retrieve the set of operations from the storage medium <NUM> to cause the mobility node <NUM> to perform the set of operations. Thus the processing circuitry <NUM> is thereby arranged to execute methods as herein disclosed.

The mobility node <NUM> may further comprise a communications interface <NUM> for communications with other nodes, entities, functions, and devices of the communication network <NUM>. As such the communications interface <NUM> may comprise one or more transmitters and receivers, comprising analogue and digital components.

The processing circuitry <NUM> controls the general operation of the mobility node <NUM> e.g. by sending data and control signals to the communications interface <NUM> and the storage medium <NUM>, by receiving data and reports from the communications interface <NUM>, and by retrieving data and instructions from the storage medium <NUM>. Other components, as well as the related functionality, of the mobility node <NUM> are omitted in order not to obscure the concepts presented herein.

<FIG> schematically illustrates, in terms of a number of functional modules, the components of a mobility node <NUM> according to an embodiment. The mobility node <NUM> of <FIG> comprises a number of functional modules; an obtain module 210a configured to perform step S102, a forward module 210c configured to perform step S106, an obtain module 210d configured to perform step S108, and an action module 210e configured to perform step S110. The mobility node <NUM> of <FIG> may further comprise a number of optional functional modules, such an obtain module 210b configured to perform step S104. In general terms, each functional module 210a-210e may be implemented in hardware or in software. Preferably, one or more or all functional modules 210a-210e may be implemented by the processing circuitry <NUM>, possibly in cooperation with the communications interface <NUM> and/or the storage medium <NUM>. The processing circuitry <NUM> may thus be arranged to from the storage medium <NUM> fetch instructions as provided by a functional module 210a-210e and to execute these instructions, thereby performing any steps of the mobility node <NUM> as disclosed herein.

<FIG> schematically illustrates, in terms of a number of functional units, the components of a policy node <NUM> according to an embodiment. Processing circuitry <NUM> is provided using any combination of one or more of a suitable central processing unit (CPU), multiprocessor, microcontroller, digital signal processor (DSP), etc., capable of executing software instructions stored in a computer program product 1010b (as in <FIG>), e.g. in the form of a storage medium <NUM>. The processing circuitry <NUM> may further be provided as at least one application specific integrated circuit (ASIC), or field programmable gate array (FPGA).

Particularly, the processing circuitry <NUM> is configured to cause the policy node <NUM> to perform a set of operations, or steps, as disclosed above. For example, the storage medium <NUM> may store the set of operations, and the processing circuitry <NUM> may be configured to retrieve the set of operations from the storage medium <NUM> to cause the policy node <NUM> to perform the set of operations. Thus the processing circuitry <NUM> is thereby arranged to execute methods as herein disclosed.

The policy node <NUM> may further comprise a communications interface <NUM> for communications with other nodes, entities, functions, and devices of the communication network <NUM>. As such the communications interface <NUM> may comprise one or more transmitters and receivers, comprising analogue and digital components.

The processing circuitry <NUM> controls the general operation of the policy node <NUM> e.g. by sending data and control signals to the communications interface <NUM> and the storage medium <NUM>, by receiving data and reports from the communications interface <NUM>, and by retrieving data and instructions from the storage medium <NUM>. Other components, as well as the related functionality, of the policy node <NUM> are omitted in order not to obscure the concepts presented herein.

<FIG> schematically illustrates, in terms of a number of functional modules, the components of a policy node <NUM> according to an embodiment. The policy node <NUM> of <FIG> comprises a number of functional modules; an obtain module 310b configured to perform step S204, a determine module 310c configured to perform step S106, and a provide module <NUM> configured to perform step S208. The policy node <NUM> of <FIG> may further comprise a number of optional functional modules, such as any of a provide module 310a configured to perform step S202, a determine module 310d configured to perform step S206a, a determine module 310e configured to perform step S206b, and a determine module 310f configured to perform step S206c. In general terms, each functional module 310a-<NUM> may be implemented in hardware or in software. Preferably, one or more or all functional modules 310a-<NUM> may be implemented by the processing circuitry <NUM>, possibly in cooperation with the communications interface <NUM> and/or the storage medium <NUM>. The processing circuitry <NUM> may thus be arranged to from the storage medium <NUM> fetch instructions as provided by a functional module 310a-<NUM> and to execute these instructions, thereby performing any steps of the policy node <NUM> as disclosed herein.

The mobility node <NUM> and/or policy node <NUM> may be provided as a standalone device or as a part of at least one further device. For example, the mobility node <NUM> and/or policy node <NUM> may be provided in a node of the core network <NUM>. Alternatively, functionality of the mobility node <NUM> and/or policy node <NUM> may be distributed between at least two devices, or nodes. These at least two nodes, or devices, may either be part of the same network part (such as the core network <NUM>) or may be spread between at least two such network parts.

Thus, a first portion of the instructions performed by the mobility node <NUM> and/or policy node <NUM> may be executed in a first device, and a second portion of the of the instructions performed by the mobility node <NUM> and/or policy node <NUM> may be executed in a second device; the herein disclosed embodiments are not limited to any particular number of devices on which the instructions performed by the mobility node <NUM> and/or policy node <NUM> may be executed. Hence, the methods according to the herein disclosed embodiments are suitable to be performed by a mobility node <NUM> and/or policy node <NUM> residing in a cloud computational environment. Therefore, although a single processing circuitry <NUM>, <NUM> is illustrated in <FIG> the processing circuitry <NUM>, <NUM> may be distributed among a plurality of devices, or nodes. The same applies to the functional modules 210a-210e, 310a-<NUM> of <FIG> and the computer programs 1020a, 1020b of <FIG>.

<FIG> shows one example of a computer program product 1010a, 1010b comprising computer readable means <NUM>. On this computer readable means <NUM>, a computer program 1020a can be stored, which computer program 1020a can cause the processing circuitry <NUM> and thereto operatively coupled entities and devices, such as the communications interface <NUM> and the storage medium <NUM>, to execute methods according to embodiments described herein. The computer program 1020a and/or computer program product 1010a may thus provide means for performing any steps of the mobility node <NUM> as herein disclosed. On this computer readable means <NUM>, a computer program 1020b can be stored, which computer program 1020b can cause the processing circuitry <NUM> and thereto operatively coupled entities and devices, such as the communications interface <NUM> and the storage medium <NUM>, to execute methods according to embodiments described herein. The computer program 1020b and/or computer program product 1010b may thus provide means for performing any steps of the policy node <NUM> as herein disclosed.

Claim 1:
A method for handling secondary radio access technology, RAT, data usage for a User Equipment, UE (130a, 130b, 130c), the method being performed by a mobility node (<NUM>), the method comprising:
obtaining (S102), from a network node (120a), an indication of data usage for the UE (130a, 130b, 130c) using the secondary RAT;
forwarding (S106) the indication towards a policy node (<NUM>);
obtaining (S108) a policy decision originating from the policy node (<NUM>), the policy decision being based on the indication of data usage; and
performing (S110) an action based on the policy decision,
wherein the policy decision is received from the policy node (<NUM>), via at least one packet gateway, PGW (<NUM>);
wherein the indication is forwarded in a Credit Control Request, CCR, message;
wherein the policy decision is obtained in a Credit Control Answer, CCA, message;
wherein the indication is forwarded and the policy decision is obtained over a Diameter Smp interface between the mobility node (<NUM>) and the policy node (<NUM>); and
wherein performing the action involves forwarding the policy decision towards the network node (120a).