GB2607560A

GB2607560A - Joining multicast sessions

Info

Publication number: GB2607560A
Application number: GB2104850.9A
Authority: GB
Inventors: Thomas Belling Horst
Original assignee: Nokia Technologies Oy
Current assignee: Nokia Technologies Oy
Priority date: 2021-04-06
Filing date: 2021-04-06
Publication date: 2022-12-14
Also published as: GB202104850D0

Abstract

Methods and apparatuses for handling policy updates in a communications system are disclosed. A request for policy update comprises an indication that a device with a unicast session is joining a multicast session and information about the multicast session. Policy rules are determined based on the information about the multicast session and the policy rules are sent in a response with an indication that the policy rules are related to quality of service (QoS) flows associated with a multicast session. It can be determined that a device with a unicast session is joining a multicast session, whereafter a request for a policy update is sent to a policy control entity (Policy Control Function, PCF). From the response a QoS flow description can be determined, and the QoS flow description can be associated with the multicast session. The request may be sent by a Session Management Function, SMF. The request message may comprise a Npcf_SMPolicyControl_Update request and the response a Npcf_SMPolicyControl_Update response. After receiving the response the SMF may notify a radio access system (RAN) serving the device of the determined QoS flow description.

Description

Joining multicast sessions

Field

The present disclosure relates to methods, apparatuses and computer program products in a communication system, and more particularly joining multicast sessions.

Background

A communication system provides a facility communication between two or more devices such as user terminals, machine-like terminals, base stations and other access points, network entities, service provider entities and/or other devices. A communication system can be provided for example by means of a communication network and one or more compatible devices providing communication channels for carrying information between the communicating entities. Communication devices, for example user devices and other terminal devices can access the communication network via access points. Communication sessions may comprise, for example, communication of data for carrying communications for services such as voice, video, electronic mail (email), text message, multimedia, control data and/or content data and so on.

In a mobile or wireless communication system at least a part of a communication session between at least two devices occurs over a wireless or radio link. Examples of wireless systems comprise public land mobile networks (PLMN), satellite-based communication systems and different wireless local networks, for example wireless local area networks (WLAN). A user can access the wider communication system via an access system means of an appropriate communication device or terminal. Non-limiting examples of communication devices are a user equipment (UE) or user device and various machine-like terminals. The wireless access can be provided by a base station of a radio access system or network. Radio access systems provide local coverage areas and are connected to a larger communication system, known as the core network. The core network comprises a wide variety of entities providing various functions and services. Similar functions and/or services may be provided by different entities in separate locations and/or by distributed data processing. At least some of the functions and/or services may be provided by virtual data processing instances. Providing data communications between the accessing devices and the ultimate service providing entities can involve intermediate and otherwise associated entities, processes and functions.

The communication system and associated devices typically operate in accordance with a given standard or specification which sets out what the various entities associated with the system are permitted to do and how that should be achieved. Communication protocols and/or parameters which shall be used for the connection are also typically defined. Examples of communication systems are those based on fifth generation (5G) networks standardized by the 3rd Generation Partnership Project (3GPP).

Multicasting is a service which enables one-to-many and many-to-many real-time communication in a network. Multicasting can serve large number of receiver devices while requiring neither prior knowledge of identities nor prior knowledge of the number of the receiver devices. A user can join a multicast session using signalling related to a unicast protocol data unit (PDU) session, and vice versa. During the transfer for unicast to multicast features such as quality of service (QoS) flows associated with the sessions shall be taken into account. Current proposals assume that information about the QoS flows for the multicast session are obtained from a Multicast Broadcast Session Management Function (MB-SMF).

Summary

In accordance with an aspect there is provided a method comprising receiving a request for a policy update, the request comprising an indication that a device with a unicast session is joining a multicast session and information about the multicast session, determining policy rules based on the information about the multicast session and sending in a response the policy rules with an indication that the policy rules are related to quality of service (QoS) flows associated with a multicast session.

In accordance with another aspect there is provided a method comprising determining that a device with a unicast session is joining a multicast session, sending a request for a policy update to a policy control entity, the request comprising an indication that the device is joining a multicast session and information about the multicast session, receiving a response from the policy control entity, wherein the response includes policy rules with an indication that the policy rules are for quality of service (QoS) flows associated with a multicast session, determining from the response a QoS flow description and associating the QoS flow description with the multicast session, and notifying a radio access system serving the device of the determined QoS flow description.

In accordance with another aspect there is provided an apparatus comprising at least one processor and at least one memory including a computer program code, the at least one memory and computer program code configured to, with the at least one processor, cause the apparatus at least to receive a request for a policy update, the request comprising an indication that a device with a unicast session is joining a multicast session and information about the multicast session, determine policy rules based on the information about the multicast session, and send in a response the policy rules with an indication that the policy rules are related to quality of service (QoS) flows associated with a multicast session.

In accordance with yet another aspect there is provided an apparatus comprising at least one processor and at least one memory including a computer program code, the at least one memory and computer program code configured to, with the at least one processor, cause the apparatus at least to determine that a device with a unicast session is joining a multicast session, send a request for a policy update to a policy control entity, the request comprising an indication that the device is joining a multicast session and information about the multicast session, receive a response from the policy control entity, wherein the response includes policy rules with an indication that the policy rules are for quality of service (QoS) flows associated with a multicast session, determine from the response a QoS flow description and associating the QoS flow description with the multicast session, and notification to a radio access system serving the device of the determined QoS flow description.

In accordance with a more specific aspect the request is received by a policy control function. The request is sent by and the response sent to a session 5 management function.

In accordance with a specific aspect, in response to receiving the request for policy update, an entity managing multicast sessions is detected, and a request for quality of service information is sent to the detected entity managing multicasts sessions. Quality of service information is received in response, and policy rules are determined based at least in part on the received quality of service information. Information of quality of service flows may also be received, and policy rules are determined based at least in part on the received information of quality of service flows. In accordance with an aspect, in response to receiving the request for policy update, a request for quality of service information is sent to an entity providing a database, and information of quality of service flows is received in response, whereafter policy rules are determined based at least in part on the received information of quality of service flows.

A request for policy update may comprise an indication that a fallback to individual delivery has occurred. Updated policy rules may be determined based on the indication that a fallback to individual delivery has occurred. The updated policy rules can be provided in response to the request for policy update.

The determining may comprise taking bandwidth into account. The determining may comprise determining which services can be provided simultaneously for the device.

Information about the multicast session may comprise at least one of an identifier of the multicast session, information about the QoS flows for the multicast session, or information describing how the QoS flows for the multicast session can be received.

An indication that policy rules are related to quality of service flows associated with a multicast session may comprise an identifier of the multicast session.

Policy rules may comprise 5G QoS Identifiers (501) which are not used for any previously installed policy rules for a user. Policy rules may contain service data flow detection information derived from information about multicast session with higher priority than for any other previously installed policy rules for a user.

When occurrence of a fallback to individual delivery is determined by an access management entity, a request for a policy update may be sent to a policy control entity. The request may comprise an indication that individual fallback occurred. Updated policy rules can then be received in response from the policy control entity.

Updated policy rules may comprise at least one of disabling a QoS flow not associated to a multicast, assigning a lower bandwidth and/or adjusting the session bandwidth.

A user plane function may be configured in accordance with the policy rules. Means for implementing the herein disclosed operations and functions can also be provided.

A computer software product embodying at least a part of the herein described functions may also be provided. In accordance with an aspect a computer program comprises instructions for performing at least one of the methods described herein.

Brief description of Drawings

Some aspects will now be described in further detail, by way of example only, with reference to the following examples and accompanying drawings, in which: Figure 1 illustrates a schematic example of a system where the herein disclosed principles can be practiced; Figure 2 shows an example of a control apparatus; Figures 3 and 4 are flowcharts according to certain examples; and Figures 5 to 9 are signaling flow charts between according to certain 30 examples.

Detailed description of examples

The following description gives an exemplifying description of some possibilities and useful background information to practise the invention. Although the specification may refer to "an", "one", or "some" examples or embodiment(s) in several locations of the text, this does not necessarily mean that each reference is made to the same example of embodiment(s), or that a particular feature only applies to a single example or embodiment. Single features of different examples and embodiments may also be combined to provide other embodiments.

Figure 1 shows a schematic presentation of system 1 comprising a radio access system 2 and a core network (CN) system shown as cloud 3. A radio access system can comprise one or a plurality of access points. A number of radio access systems can be connected to the core network. In Figure 1 the access point and the radio access system are schematically presented by a base station. An access point can comprise any node that can transmit/receive radio signals (e.g., a TRP, a base station such as gNB, eNB, a user device such as a UE and so forth). An example of wireless access architecture is 30PP 50 radio access architecture. However, embodiments are not limited to such an architecture.

A communications device 10 can be located in the service area of the radio access system 2 and can thus communicate wirelessly with the access point provided by the system 2. The communications device 10 is an example of a user which can request for one or more services provided by entities of the core network 3. The device can be associated with a unique user identity. The user identity may be assigned to the device, to a user of the device or a subscription by a user of the device. The device 10 may be any suitable communications device adapted for wireless communications. Non-limiting examples comprise a mobile station (MS) (e.g., a mobile device such as a mobile phone or what is known as a 'smart phone'), a computer provided with a wireless interface card or other wireless interface facility (e.g., USB dongle), personal data assistant (FDA) or a tablet provided with wireless communication capabilities, machine-type communications (MTC) devices, Internet of Things (loT) type communications devices or any combinations of these or the like. The device may be provided as part of another device. The device may receive signals over an air or radio interface via appropriate apparatus for receiving and may transmit signals via appropriate apparatus for transmitting radio signals. The communications can occur via multiple paths. Multiple input multiple output (MIMO) type communications may be provided with multiantenna elements.

The wider communication system (core network) 3 can comprise a 5G core network (5GC) and entities providing one or more interconnected network functions (NF). The system can comprise one or more data networks (DN). In Figure 1 blocks 11 to 20 denote various possible network entities. The non-liming and non-exhaustive list of these include an access and mobility management function (AMF) 11, a session management function (SMF) 12, a policy control function (PCF) 13, network function repository function (NRF) 14, Binding Support Function (BSF) 15, multicast broadcast policy control function (MB-PCF) 16, Unified Data Repository (UDR) 17, multicast broadcast session management function (MB-SMF) 18, and multicast broadcast user plane function (MB-UPF) 19. A plurality of content providers 20 can also be provided. Other management, control and application functions are also possible. It shall be appreciated that at least some of the entities denoted by blocks 11 to 20 can be provided as virtual data processing instances in virtualized environment.

Functions of devices such as the access point 2 or the accessing device 10 and any of the network entities 11 to 20 can be provided by data processing apparatus. The data processing can be provided by apparatus comprising at least one processor and at least one memory. Figure 2 shows an example of a data processing apparatus 50 comprising processor(s) 52, 53 and memory or memories 51. Figure 2 further shows connections between the elements of the apparatus and an interface for connecting the data processing apparatus to other components of the device. The at least one memory may comprise at least one ROM and/or at least one RAM. The communications device may comprise other possible components for use in software and hardware aided execution of tasks it is designed to perform and implementing the herein described features. The at least one processor can be coupled to the at least one memory. The at least one processor may be configured to execute an appropriate software code to implement one or more of the following aspects. The software code may be stored in the at least one memory, for example in the at least one ROM.

The processing may be distributed between several processors. The processing may be provided by virtual data processing instances such as virtual machines or separated cores (containers) operated on a shared operating system resource. In this specification the term entity covers such virtual data processing instances.

The following describes in more detail certain illustrative examples and non-limiting aspects of operations, configurations and signaling using 3GPP 5G Core Network (5GC) terminology.

A device, for example the user equipment (UE) 10 can register itself with relevant core network function or functions to be able to access and use the desired service available in the system 1. For example, the device may need to register with the Access and Mobility Management Function (AMF) 11. The user equipment (UE) can join a multicast session using signalling related to a unicast protocol data unit (PDU) session.

In 5G the quality of service (QoS) is flow based. Packets are classified and marked using QoS Flow Identifier (OF!). The QoS flows are mapped in the access network to Data Radio Bearers (DRBs). The 5G QoS model supports both QoS Flows that require guaranteed flow bit rate and QoS Flows that do not require guaranteed flow bit rate. The 5G QoS model also supports Reflective QoS. The QoS Flow is the finest granularity of QoS differentiation in the PDU Session. User Plane traffic with the same QFI within a PDU Session receives the same traffic forwarding treatment. OR shall be used for all PDU Session Types. The OH shall be unique within a PDU Session.

At the time when the UE joins a multicast session, quality of service (QoS) flows associated to the multicast session can be added by a session management function (SMF) to the unicast PDU session. The QoS flows are marked as being associated with the multicast session in preparation to a fallback to individual delivery of multicast content via the PDU session during a handover to a Next / 5th Generation Radio Access Network (NG-RAN) node that may not be configured to support Multicast-broadcast services in 5G (5MBS) or for an immediate start of individual delivery to such a RAN node.

The SMF can obtain information about the QoS flows for the multicast session from a Multicast Broadcast Session Management Function (MB-SMF) but this may not always be possible. Other QoS flows can be determined by the SMF based on policy rules supplied by a policy control function (PCF). QoS flows contain QoS rules with packet filters and priorities and QoS Flow IDs (QFIs). These need to be harmonized and decided upon based on policies. Total available bandwidth may also need to be taken into account. Policy control may also ned to be able to decide which services the user can obtain simultaneously.

Below some possibilities to address these issues are described.

Figure 3 shows a flowchart for a method in a policy controller entity of communication system where a request for a policy update is received at 100. The request comprises an indication that a device with a unicast session is joining a multicast session and information about the multicast session. The information about the multicast session can comprise, for example, an identifier of the multicast session, and/or information about the QoS flows for the multicast session, and/or information describing how the QoS flows for the multicast session can be received. For example, the information may comprise an address for the source of the QoS flow information or a multicast destination address. The controller entity can determine at 102 policy rules for quality of service flows based on quality of service information for the indicated multicast session and stored policies.

The stored policies can, for example, relate to permissible services, related priorities and allowed maximum QoS for the permissible services as well as total permissible QoS and bandwidth. The stored policies may depend on the served user. As an example, the controller may add new policy rules (PCC rules) with the QoS requirements and service data flow detection information derived from the information about the QoS flows for the multicast session and with higher priority than any other previously installed policy rules, The controller may assign 5G QoS Identifiers (501) to the new policy rules which are not used for any previously installed policy rules for the user. The controller may also adjust the total bandwidth for the user to accommodate the bandwidth requirements of the new QoS flows.

A response can then be sent at 104. In the response the policy rules for quality of service flows for the multicast session are provided with an indication that the policy rules are related to quality of service flows associated with a multicast session. The response may also indicate an identifier of the multicast session.

The request can be received by a policy control function from a session management function.

Detection of an entity managing multicast sessions may be needed. A request for quality of service information can then be sent to the detected entity managing multicasts sessions, and in response quality of service information can be received. The updated policy rules can be based at least in part on the received quality of service information.

In accordance with another example detection of an entity managing multicast policies is performed. A request for quality of service information to the detected entity managing multicasts policies is then sent. In response information of quality of service flows can be received, and updated policy rules can be based at least in part on the received information of quality of service flows.

A request for quality of service information to an entity providing a unified data repository may also be sent. In response information of quality of service flows can be received. The updated policy rules can then be based at least in part on the received information of quality of service flows.

At least one unicast flow may be disabled based on the priority thereof. At least one low priority unicast flow may be disabled.

Bandwidth can be taken into account in determining the updated policy It can also be determined determining which services can be provided simultaneously for the device.

Figure 4 shows an example of a method in a service managing entity of communication system. It can be determined at 200 that a device with a unicast session is joining a multicast session. A request for a policy update can then be sent at 202 to a policy control entity. The request comprises an indication that the device is joining a multicast session and information about the multicast session. The information about the multicast session can comprise, for example, an identifier of the multicast session, information about the QoS flows for the multicast session, and/or information describing how the QoS flows for the multicast session can be received, for example an address of the source of the information or a multicast destination address.

A response is received from the policy control entity at 204, the response including policy rules with an indication that the policy rules are for quality of service flows associated with a multicast session. An identifier of the multicast session may be provided as indication that the policy rules are for quality of service flows associated with a multicast session, A user plane function can be configured to handle packets according to the policy rules and to detect incoming packets.

At 206 an indication containing QoS flow description and associating the QoS flow description with the multicast session is determined from the response.

A radio access system serving the device may be notified with the determined indication at 208. The indication associating the QoS flow description with the multicast session may be used radio access system to determine that no radio resources need to be reserved for those QoS flows.

The notification may be communicated to an entity providing access and mobility management function.

The request for policy update can include information of the quality of service flows associated with the multicast session. The information of the quality of service flows being can be obtained from a multicast broadcast session management function subsequent to determination that no prior knowledge about the multicast session is available.

In accordance with an example implementation the session management function (SMF) can inform a policy control function (PCF) that a user equipment (UE) has joined a multicast session. The PCF can provide in response policy rules for associated quality of service (QoS) flows. The policy rules can be provided with an indication that the policy rules are for the associated QoS flows. The PCF can determine the policy rules from the QoS flow information for the multicast session and select OFIs and priorities. This can be provided taking into account information of other installed policy and charging control (FCC) rules. The flowcharts of Figures 5 to 9 show more detailed examples of providing the rules. Before explaining the exemplifying possibilities to implement the herein disclosed principles, an explanation of a possible underlying signalling flow for a UE joining a multicast session is given with reference to Figure 5. Multicast group configuration can be formed in stage 1 in the core network. This can take place in any appropriate manner and involve entities such as an NRF, MB-SMF, MBUPF, MBSF and the content provider of the multicast group. In stage 2 the UE can perform registration and PDU session establishment to initiate a PDU session with the communication system. The UE can access the core network via a radio access network (RAN) and register via the AMF with entities such as SMF and PCF.

At stage 3 a multicast announcement is given. The UE decides to join the multicast group and sends a message 4 'PDU session modification request' to the AMF. The AMF then sends message 5 to the SMF to update the PDU session SMcontext. UE authorisation check can follow at stage 6.

In the next stage in Figure 5, if it is determined that the SMF has no cached knowledge about the multicast session, the SMF can exchange in messages 7, 8 and 9 information with the NRF and the MB-SMF to obtain information about the quality of service (QoS) requirements. Information of QoS flows is provided by the MB-SMF in message 9 for the given multicast session. The multicast session joining procedure can then continue by the SMF sending message 12 to the AMF and so forth, as illustrated by messages 13 -25 in Figure 5.

In accordance with a possibility shown in the flowchart of Figure 5, additional exchange of messages is performed after the SMF performs MB-SMF detection and before the session management function (SMF) sends the Namf Communication N1N2Message transfer notification in message 12 to the AMF. At this stage the SMF can send an update request 10 to the PCF. The message informs the PCF of the event where the UE is joining a multicast session and provides information of QoS flows obtained from the MB-SMF in message 9 for the given multicast session. The message informs the PCF that the UE is joining the multicast session and the identity of the multicast session. The PCF responds the SMF by message 11 of Figure 5 including PCC rules for the associated quality of service (QoS) flows of the multicast session containing an indication that the PCC rules relate to multicast flows and/or the multicast session identifier. The PCF has determined the policy rules based on QoS flow information for the multicast session and selected 501s and priorities taking into account information of other installed policy and charging control (PCC) rules.

In accordance with another example shown in Figure 6, the SMF informs the PCF by message 7 of an event where a UE joins a multicast session. This can be sent in response to the PDU update message 5 and after UE authorization check at stage 6. The update request message 7 can include notification of the event that UE has joined and ID of the multicast session. The PCF can perform MB-SMF detection with NRF though exchange of messages at 8. The PCF can then fetch information of the QoS flows by exchange of messages 9 and 10 for the indicated multicast session from the MB-SMF. The PCF can then send update response message 11 to the SMF including PCC rules containing an indication that the PCC rules relate to multicast flows and/or the multicast session identifier.

In accordance with an example shown in Figure 7, following a PDU update message 5 and UE authorization check at stage 6, the SMF can inform the PCF that the UE joined a multicast session. The update request message 7 can include notification of the event that UE has joined and ID of the multicast session. The PCF can perform MB-PCF detection with BSF though exchange of messages at 8 based on the MBS session ID. The PCF can then fetch QoS flows for that multicast session from the determined MB-PCF by sending MC QoS request 9 including the multicast session ID. Information of the QoS flows is received by the PCF in the response message 10 from the MB-PCF. The PCF can then send update response message 11 to the SMF including PCC rules containing an indication that the PCC rules relate to multicast flows and/or the multicast session identifier.

In accordance with an example shown in Figure 8, following PDU update message 5 and UE authorization check at stage 6, the SMF sends an update request 7 to the PCF. The update request message 7 can include notification of the event that UE has joined and ID of the multicast session. A MB-PCF controlling MB-SMF stores information about QoS flows for a multicast session in a database such as an UDR. In response to the SMF informing the PCF that UE joined a multicast session the PCF can thus fetch QoS flows for that multicast session from the UDR by message 8. The flows are received in a response message 9. The PCF can then send update response message 11 to the SMF including FCC rules containing an indication that the FCC rules relate to multicast flows and/or the multicast session identifier.

Figure 9 shows an example where shared delivery of ongoing multicast data to a UE at stage 1 is handed over at stage 2 to a RAN node that does not support the MBS used for the delivery. The SMF decided at stage 3 that individual deliver shall be applied instead. The SMF informs by update request message 4 the PCF that individual fallback occurs. The PCF may then adjust at stage 5 policy rules. For example, the PCF may disable low priority services not related to the multicast session and/or increase the session bandwidth (AMBR) by adding the bandwidth required for QoS flows associated to the multicast service. The PCF can then send update response message 6 to the SMF including information of updated policy rules. The operation of this example can be combined with any of the above examples, but can also be performed subsequent to those examples It is noted that while the above describes example embodiments, there are several variations and modifications which may be made to the disclosed solution without departing from the scope of the present invention. Different 25 features from different embodiments may be combined.

The embodiments may thus vary within the scope of the attached claims. In general, some embodiments may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. For example, some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device, although embodiments are not limited thereto. While various embodiments may be illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that these blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

The embodiments may be implemented by computer software stored in a memory and executable by at least one data processor of the involved entities or by hardware, or by a combination of software and hardware. At least a part of the functions can be provided in virtualised environment, and at least some of the entities can be provided as virtual computing instances. Further in this regard it should be noted that any of the above procedures may represent program steps, or interconnected logic circuits, blocks and functions, or a combination of program steps and logic circuits, blocks and functions. The software may be stored on such physical media as memory chips, or memory blocks implemented within the processor, magnetic media such as hard disk or floppy disks, and optical media such as for example DVD and the data variants thereof, CD.

The memory may be of any type suitable to the local technical environment and may be implemented using any suitable data storage technology, such as semiconductor based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory. The data processors may be of any type suitable to the local technical environment, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs), application specific integrated circuits (ASIC), gate level circuits and processors based on multi core processor architecture, as non-

limiting examples.

Alternatively or additionally some embodiments may be implemented using circuitry. The circuitry may be configured to perform one or more of the functions and/or method procedures previously described. That circuitry may be provided in the network entity and/or in the communications device and/or a server and/or a device.

As used in this application, the term "circuitry" may refer to one or more or all of the following: (a) hardware-only circuit implementations (such as implementations in only analogue and/or digital circuitry); (b) combinations of hardware circuits and software, such as: (i) a combination of analogue and/or digital hardware circuit(s) with software/firmware and (ii) any portions of hardware processor(s) with software (including digital signal processor(s)), software, and memory(ies) that work together to 10 cause the communications device and/or device and/or server and/or network entity to perform the various functions previously described; and (c) hardware circuit(s) and or processor(s), such as a microprocessor(s) or a portion of a microprocessor(s), that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for 15 operation.

This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and/or firmware. The term circuitry also covers, for example integrated device.

It is noted that whilst embodiments have been described in relation to certain architectures, similar principles can be applied to other systems. Therefore, although certain embodiments were described above by way of example with reference to certain exemplifying architectures for wireless networks, technologies standards, and protocols, the herein described features may be applied to any other suitable forms of systems, architectures and devices than those illustrated and described in detail in the above examples. It is also noted that different combinations of different embodiments are possible. It is also noted herein that while the above describes exemplifying embodiments, there are several variations and modifications which may be made to the disclosed solution without departing from the spirit and scope of the present invention.

Claims

Claims 1. A method in a communication system, comprising: receiving a request for a policy update, the request comprising an indication that a device with a unicast session is joining a multicast session and information about the multicast session, determining policy rules based on the information about the multicast session, and sending in a response the policy rules with an indication that the policy rules are related to quality of service (QoS) flows associated with a multicast session.
2. A method according to claim 1, wherein the request is received by a policy control function from a session management function.
3. A method according to claim 1 or 2 comprising, in response to receiving the request for policy update, detection of an entity managing multicast sessions, sending a request for quality of service information to the detected entity managing multicasts sessions, receiving in response quality of service information, and determining the policy rules based at least in part on the received quality of service information.
4. A method according to claim 1 or 2 comprising, in response to receiving the request for policy update, detection of an entity managing multicast policies, sending a request for quality of service information to the detected entity managing multicasts policies, receiving in response information of quality of service flows, and determining the policy rules based at least in part on the received information of quality of service flows.
5. A method according to claim 1 or 2 comprising, in response to receiving the request for policy update, sending a request for quality of service information to an entity providing a database, receiving in response information of quality of service flows, and determining the policy rules based at least in part on the received information of quality of service flows.
6. A method according to any preceding claim comprising receiving the request for a policy update, the request comprising an indication that a fallback to individual delivery has occurred, determining updated policy rules based on the indication that a fallback to individual delivery has occurred, and providing the updated policy rules in response to the request for policy update.
7. A method according to any preceding claim, wherein the determining comprises taking bandwidth into account.
8. A method according to any preceding claim, wherein the determining comprises determining which services can be provided simultaneously for the device.
9. A method in a communication system, comprising: determining that a device with a unicast session is joining a multicast session, sending a request for a policy update to a policy control entity, the request comprising an indication that the device is joining a multicast session and information about the multicast session, receiving a response from the policy control entity, wherein the response includes policy rules with an indication that the policy rules are for quality of service (QoS) flows associated with a multicast session, determining from the response a QoS flow description and associating the QoS flow description with the multicast session, and notifying a radio access system serving the device of the determined QoS flow description.
10. A method according to claim 9, comprising sending the notification to an entity providing access and mobility management function.
11. A method according to any preceding claim, wherein the information about the multicast session comprises at least one of an identifier of the multicast session, information about the QoS flows for the multicast session, and information describing how the QoS flows for the multicast session can be received.
12. A method according to any preceding claim, wherein the indication that the policy rules are related to quality of service flows associated with a multicast session comprise an identifier of the multicast session
13. A method according to any preceding claim, wherein the policy rules contain 5G QoS Identifiers (5QI) which are not used for any previously installed policy rules for the user.
14. A method according to any preceding claim, wherein the policy rules contain service data flow detection information derived from the information about the multicast session with higher priority than for any other previously installed policy rules for the user.
15. A method according to claim 9 or any claim dependent on claim 9, comprising determining that a fallback to individual delivery occurred, sending a request for a policy update to the policy control entity, the request comprising an indication that individual fallback occurred, and receiving updated policy rules from the policy control entity.
16. A method according to any preceding claim, wherein updated policy rules comprise at least one of disabling a QoS flow not associated to a multicast, assigning a lower bandwidth and/or adjusting the session bandwidth.
17. A method according to any preceding claim, comprising configuring a user plane function in accordance with the policy rules.
18. An apparatus comprising at least one processor and at least one memory including a computer program code, the at least one memory and computer program code configured to, with the at least one processor, cause the apparatus at least to: receive a request for a policy update, the request comprising an indication that a device with a unicast session is joining a multicast session and information about the multicast session, determine policy rules based on the information about the multicast session, and send in a response the policy rules with an indication that the policy rules are related to quality of service (QoS) flows associated with a multicast session.
19. An apparatus according to claim 18 configured to, in response to receiving the request for policy update, detect an entity managing multicast sessions, send a request for quality of service information to the detected entity managing multicasts sessions, receive in response quality of service information, and determine policy rules based at least in part on the received quality of service information.
20. A apparatus according to claim 18 configured to, in response to receiving the request for policy update, detect an entity managing multicast policies, send a request for quality of service information to the detected entity managing multicasts policies, receive in response information of quality of service flows, and determine policy rules based at least in part on the received information of quality of service flows.
21. A apparatus according to claim 18 configured to, in response to receiving the request for policy update, send a request for quality of service information to an entity providing a database, receive in response information of quality of service flows, and determine the policy rules based at least in part on the received information of quality of service flows.
22. An apparatus according to any of claims 18 to 21, configured to receive the request for a policy update, the request comprising an indication that a fallback to individual delivery has occurred, determine updated policy rules based on the indication that a fallback to individual delivery has occurred, and provide the updated policy rules in response to the request for policy update.
23. An apparatus according to any of claims 18 to 22, configured to determine services that can be provided simultaneously for the device and/or bandwidth.
24. An apparatus according to any of claims 18 to 23, comprising a policy control function configured to receive the request from a session management function.
25. An apparatus comprising at least one processor and at least one memory 10 including a computer program code, the at least one memory and computer program code configured to, with the at least one processor, cause the apparatus at least to: determine that a device with a unicast session is joining a multicast session, send a request for a policy update to a policy control entity, the request comprising an indication that the device is joining a multicast session and information about the multicast session, receive a response from the policy control entity, wherein the response includes policy rules with an indication that the policy rules are for quality of service (QoS) flows associated with a multicast session, determine from the response a QoS flow description and associating the QoS flow description with the multicast session, and notification to a radio access system serving the device of the determined QoS flow description.
26. An apparatus according to claim 25, configured to notify an entity providing access and mobility management function of the determined QoS flow description.
27. An apparatus according to any of claims 18 to 26, wherein the information about the multicast session comprises at least one of an identifier of the multicast session, information about the QoS flows for the multicast session, or information describing how the QoS flows for the multicast session can be received.
28. An apparatus according to any of claims 18 to 27, wherein the indication that the policy rules are related to quality of service flows associated with a multicast session comprise an identifier of the multicast session
29. An apparatus according to any of claims 18 to 28, wherein the policy rules contain 5G QoS Identifiers (501) which are not used for any previously installed policy rules for the user and/or service data flow detection information derived from the information about the multicast session with higher priority than for any other previously installed policy rules for the user.
30. An apparatus according to claim 25 or any claim dependent on claim 25, configured to determine that a fallback to individual delivery occurred, send a request for a policy update to the policy control entity, the request comprising an indication that individual fallback occurred, and receive updated policy rules from the policy control entity.
31. An apparatus according to any of claims 18 to 30, configured to participate in configuring of a user plane function in accordance with the policy rules.
32. An apparatus according to any of claims 18 to 31, wherein updated policy rules comprise disabling a QoS flow not associated to a multicast, assigning a lower bandwidth and/or adjusting the session bandwidth.
33. A computer readable media comprising program code for causing a processor to perform instructions for a method as claimed in any of claims 1 to 18.