Patent ID: 12192858

DETAILED DESCRIPTION

Some of the embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. Other embodiments, however, are contained within the scope of the subject matter disclosed herein, the disclosed subject matter should not be construed as limited to only the embodiments set forth herein; rather, these embodiments are provided by way of example to convey the scope of the subject matter to those skilled in the art. Additional information may also be found in the document(s) provided in Appendix D.

Radio Node: As used herein, a “radio node” is either a radio access node or a wireless device.

Radio Access Node: As used herein, a “radio access node” or “radio network node” is any node in a radio access network of a cellular communications network that operates to wirelessly transmit and/or receive signals. Some examples of a radio access node include, but are not limited to, a base station (e.g., a New Radio (NR) base station (gNB) in a Third Generation Partnership Project (3GPP) Fifth Generation (5G) NR network or an enhanced or evolved Node B (eNB) in a 3GPP Long Term Evolution (LTE) network), a high-power or macro base station, a low-power base station (e.g., a micro base station, a pico base station, a home eNB, or the like), and a relay node.

Core Network Node: As used herein, a “core network node” is any type of node in a core network or any node that implements a core network function. Some examples of a core network node include, e.g., a Mobility Management Entity (MME), a Packet Data Network Gateway (PGW), a Service Capability Exposure Function (SCEF), a Home Subscriber Server (HSS), or the like. Some other examples of a core network node include a node implementing a Access and Mobility Function (AMF), a UPF, a Session Management Function (SMF), an Authentication Server Function (AUSF), a Network Slice Selection Function (NSSF), a Network Exposure Function (NEF), a Network Function (NF) Repository Function (NRF), a Policy Control Function (PCF), a Unified Data Management (UDM), or the like.

Wireless Device: As used herein, a “wireless device” is any type of device that has access to (i.e., is served by) a cellular communications network by wirelessly transmitting and/or receiving signals to a radio access node(s). Some examples of a wireless device include, but are not limited to, a User Equipment device (UE) in a 3GPP network and a Machine Type Communication (MTC) device.

Network Node: As used herein, a “network node” is any node that is either part of the radio access network or the core network of a cellular communications network/system.

Note that the description given herein focuses on a 3GPP cellular communications system and, as such, 3GPP terminology or terminology similar to 3GPP terminology is oftentimes used. However, the concepts disclosed herein are not limited to a 3GPP system.

Note that, in the description herein, reference may be made to the term “cell”; however, particularly with respect to 5G NR concepts, beams may be used instead of cells and, as such, it is important to note that the concepts described herein are equally applicable to both cells and beams.

Embodiments of the present disclosure are is described within the context of a 3GPP-based LTE network, i.e. an EPS including E-UTRAN and EPC. However, the problems and solutions described herein are equally applicable to wireless access networks and user-equipment (UE) implementing other access technologies and standards (e.g. a 5G system including 5G core and 5G radio access). LTE is used as an example technology where the embodiments described herein are suitable for LTE and using LTE in the description therefore is particularly useful for understanding the problem and solutions solving the problem. Furthermore, embodiments of the present disclosure focus on the IOPS mode of operation; however, the problems and solutions described herein are also equally applicable to other scenarios, e.g. for the case of implementing a private network, a.k.a. non-public networks (NPN), with a local EPC or 5GC to provide application services to authorized users within the private network coverage area.

Systems and methods for supporting MBMS transmissions for MC group communications on the IOPS mode of operation are provided, where the MC services are directly provided by the MC users and transmitted over an IOPS MC system and an IOPS EPS network.

FIG.2

In this regard,FIG.2illustrates one example of a cellular communications system200in which embodiments of the present disclosure may be implemented. In the embodiments described herein, the cellular communications system200is an Evolved Packet System (EPS) including a LTE RAN; however, the present disclosure is not limited thereto. The embodiments disclosed herein are equally applicable to other technologies such as, e.g., 5G. In this example, the RAN includes base stations202-1and202-2, which in LTE are referred to as eNBs, controlling corresponding (macro) cells204-1and204-2. The base stations202-1and202-2are generally referred to herein collectively as base stations202and individually as base station202. Likewise, the (macro) cells204-1and204-2are generally referred to herein collectively as (macro) cells204and individually as (macro) cell204. The RAN may also include a number of low power nodes206-1through206-4controlling corresponding small cells208-1through208-4. The low power nodes206-1through206-4can be small base stations (such as pico or femto base stations) or Remote Radio Heads (RRHs), or the like. Notably, while not illustrated, one or more of the small cells208-1through208-4may alternatively be provided by the base stations202. The low power nodes206-1through206-4are generally referred to herein collectively as low power nodes206and individually as low power node206. Likewise, the small cells208-1through208-4are generally referred to herein collectively as small cells208and individually as small cell208. The cellular communications system200also includes a core network210, which in the 5GS is referred to as the 5G core (5GC). The base stations202(and optionally the low power nodes206) are connected to the core network210.

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

Now, a description of some example embodiments of the present disclosure will be provided. Throughout the present disclosure, it is assumed that the public safety users, also refer here as MC service UEs or MC users or just UEs or users, have been provided with the configuration needed to utilize any MC service. Such a configuration, to be defined here as the MC service user configuration profile, is assumed to be stored at the UEs (e.g., stored by MC service clients operating on the UEs). For each UE, the MC service user configuration profile may comprise information (e.g., static data) needed for the configuration of the MC service (e.g., MCPTT service) that is supported by the UE in question. For each UE, the MC service user configuration profile may contain information about at least one of: the current UE configuration, MC service user profile configuration, group configuration (e.g., group ID), and service configuration data or similar which is stored at the UE for off-network operation (e.g., specific parameters are described in 3GPP TS 23.280 V16.3.0 Annex A and 3GPP TS 23.379 V16.2.0 Annex A for the MC services and MCPTT service UE/off-network, respectively). The MC service user configuration profile can be provisioned by either offline procedures or after the UEs have been authenticated and registered with the central MC system.

The user configuration profile can also include specific configuration to be utilized on the IOPS mode of operation. It can include specific IOPS group configuration, e.g. group IP multicast addresses associated to the IOPS group(s) a user belongs to. For the IOPS group configuration, the same off-network group configuration could be also utilized.

In the case there is a link failure between the radio access network (eNBs) and the macro core network (EPC), it is assumed that the IOPS mode of operation is initiated, i.e. an off-network like operation, where the MC services are directly provided by the MC users, but the corresponding MC service IP packets are transmitted over the IOPS MC system. For that, authorized UEs have been configured to support the IOPS mode of operation.

When the IOPS mode of operation is initiated, an IOPS EPS network (i.e. IOPS-capable eNB(s) connected to a local EPC) provides local connectivity to UEs which are in the coverage area of this IOPS EPS network. For support of MC services in the IOPS mode of operation, the IOPS MC system, i.e. the IOPS AF, enables MC users to be registered and discovered. Also, the IOPS AF provides supporting IP connectivity among the users, i.e. the IOPS AF distributes IP packets received from an MC user targeting one or more MC users.

Throughout the present disclosure, the support of group communications on the IOPS mode of operation is addressed based on multicast, i.e. MBMS-based, transmissions. For that, it is assumed that the laps AF supports functionalities of a group communication service application server (GCS AS) to establish MBMS bearers and distribute IP packets via multicast-broadcast transmissions. Also, it is assumed that the local EPC supports MBMS.

MC Service Group Communication Support on the IOPS Mode of Operation Based on Always MBMS-Based Transmissions

In one embodiment, in the IOPS mode of operation, the eNB(s) within the IOPS system are configured to be part of the same MBSFN area, i.e. one IOPS system consists of only one MBSFN area. This MBSFN area is referred to herein as the IOPS MBSFN area.

When the IOPS mode of operation is initiated, the IOPS AF pre-establishes an MBMS bearer within the IOPS MBSFN area. This MBMS bearer is referred to herein as the IOPS MBMS bearer or IOPS TMGI. This means that the establishment of the IOPS MBMS bearer may already occur before the IOPS AF discovers any user(s) in the IOPS mode of operation. Hence, the IOPS AF efficiently establishes an MBMS bearer before the initiation of any group communication session during the IOPS mode of operation.

For the IOPS MBMS bearer establishment, the IOPS AF sends an MBMS bearer establishment request to the Broadcast-Multicast Service Centre (BM-SC) supporting MBMS within the local EPC. The IOPS MBMS bearer, i.e. the IOPS TMGI, is then identified by the BM-SC with a specific UDP port.

In one embodiment, when the IOPS AF has discovered a user(s), the IOPS AF announces to the discovered user(s) the IOPS MBMS bearer. The IOPS AF indicates to the users that group communication sessions are transmitted over the IOPS MBMS bearer. Thereby, the user(s) starts monitoring the IOPS MBMS bearer to receive data being addressed to its pre-configured group IP multicast address(es) over the corresponding IOPS TMGI.

The IOPS MBMS bearer is established to transmit the IP packets received by the IOPS AF that are related to group communication sessions. In one embodiment, all the IP packets related to group communication sessions are always transmitted from the IOPS AF over the IOPS MBMS bearer on the IOPS mode of operation. For that, the IOPS AF transmits the received IP packets using an outer IP header with the BM-SC IP address and the UDP port associated to the corresponding TMGI. The BM-SC then transmits the IP packets to the corresponding eNB(s) associated to the IOPS TMGI, as described in 3GPP TS 23.468 and 3GPP TS 29.468.

On the other hand, IP packets received by the IOPS AF that are related to a one to one communication session are transmitted via unicast bearers via the local EPC.

In one embodiment, during the IOPS discovery procedure, the MC users do not publish any user group information to the IOPS AF. This mitigates security risks related to storing user group configuration on the IOPS AF during the IOPS mode of operation.

As the IOPS AF does not look into the payload of the received IP packets, in one embodiment, the IOPS AF determines if a received IP packet is related to a group communication session based on the type of IP address of the actual destination IP address. The actual destination IP address is the one contained within the inner IP header of the received IP packet. Therefore, when the IOPS AF identifies that the IP address type of the actual destination IP address is a multicast IP address, the IOPS AF determines that it is an IP packet related to a group communication session. Subsequently, the IOPS AF distributes the received IP packet over the IOPS MBMS bearer, i.e. the IOPS TMGI, to be broadcasted to the users within the IOPS system coverage. For the case of a unicast IP address type, the IOPS AF distributes the received IP packets via unicast transmissions.

Hence, in one embodiment, the IOPS AF is configured to distribute all IP packets with a destination IP multicast address over the already established IOPS MBMS bearer. As all discovered MC users have been already requested to monitor the IOPS MBMS bearer, it is up to the MC users to filter and decode only those IP packets being addressed to the group IP multicast addresses which have been preconfigured within the user configuration profile. Subsequently, the MC users discard all other received IP packets, i.e. those IP packets addressed to non-preconfigured group IP multicast addresses.

In one embodiment, the IOPS AF may decide to dynamically establish additional IOPS MBMS bearers, i.e. additional TMGIs, based on the IP multicast addresses being identified from the received IP packets. For instance, when the IOPS AF identifies for the first time that IP packets are being addressed to an IP multicast address, i.e. addressing a group of users, the IOPS AF dynamically establishes a new TMGI to transmit only all related IP packets targeting the corresponding IP multicast address. Subsequently, the IOPS AF announces to all the discovered users that a new TMGI has been configured for the corresponding IP multicast address. Therefore, only users who have interest in this group, i.e. users who have been preconfigured with the corresponding IP multicast address, start monitoring the corresponding TMGI. Other users then are not required to monitor such a TMGI.

FIG.3

FIG.3depicts the described MBMS configuration to support MC service group communications based on always MBMS-based transmissions. In this example, the IOPS EPS includes two IOPS-capable eNBs (denoted eNB1 and eNB 2), a local EPC, and an IOPS AF. Note that the local EPC and the IOPS AF may be implemented at one or more network nodes that are external from but connected to the eNBs (e.g., via direct connection or local network) or, alternatively, may be implemented as part of one of the eNBs. The IOPS AF includes an IOPS connectivity function and an IOPS distribution function. The IOPS system provides connectivity to a number of MC UEs, denoted MC UE 1, MC UE 2, MC UE 3, and MC UE 4. As described above, the IOPS AF pre-establishes the IOPS MBMS bearer within the IOPS MBSFN area. Subsequently, the IOPS AF (in particular the IOPS connectivity function) discovers the MC UEs 1, 2, 3, and 4. As discussed above, the IOPS AF (in particular the IOPS distribution function) transmits the IP packets received by the IOPS AF that are related to group communication sessions over the IOPS MBMS bearer.

FIGS.4A and4B

FIGS.4A and4Billustrate the operation of the IOPS EPS ofFIG.3in accordance with at least some aspects of the embodiments described above. InFIG.4, the MC UEs 1, 2 and 3 are assumed to belong to the same IOPS group X, i.e. the users have been preconfigured with a group IP multicast address X associated to the IOPS group X. The steps of the procedure illustrated inFIGS.4A and4Bare as follows:1. Before the IOPS mode of operation is initiated, it is assumed that the UEs are registered to the macro PLMN network and MC services are supported based on normal on-network operation.2. The IOPS-cable eNB(s) detects that it lost connectivity to the macro EPC. Hence, all UEs within the coverage area of the eNB(s) are detached from the network.3. The IOPS mode of operation is initiated, i.e. the eNB(s) is an IOPS-capable eNB(s) and begins broadcasting the IOPS PLMN. The IOPS PLMN network is based on an available local EPC supporting the IOPS mode of operation. The IOPS AF also begins operating together with the local EPC to support MC services on the IOPS mode of operation. The local EPC supports MBMS and the cells served by the eNB(s) are configured to form the IOPS MBSFN area.4. The IOPS AF sends a request to the local EPC to establish a MBMS bearer, i.e. the IOPS MBMS bearer, within the IOPS MBSFN area. The IOPS MBMS bearer is then established and associated to a TMGI and UDP port.5. Upon the detection of the IOPS PLMN, the UEs register to the IOPS network.6. The MC UEs initiate the IOPS discovery procedure and become discovered by the IOPS AF. As part of the discovery procedure the MC UEs are not required to publish any group configuration.7. Once a MC UE(s) is discovered by the IOPS AF, the IOPS AF announces the IOPS MBMS bearer. The IOPS AF indicates to the MC UE(s) that group communication sessions are transmitted over the IOPS MBMS bearer.8. The MC UE(s) start monitoring the IOPS MBMS bearer and start sending the MBMS listening status report to the IOPS AF.9. In this example, MC UE 1 initiates a group call with the preconfigured IOPS group X. For that, the MC UE 1 encapsulates the related IP packets within IP to be transmitted to the targeted group's UEs via the IOPS AF. Therefore, the IP packets contain an inner IP header and an outer IP header. The inner IP header includes, as destination IP address, the associated preconfigured group IP multicast address of the IOPS group X. The outer IP header includes the configured IP address of the IOPS distribution function at the IOPS AF.10. The group call related IP packets are transmitted to the IOPS AF.11. In this example, the IOPS AF, in this case the IOPS distribution function, receives the IP packets and determine if the inner IP address type is a multicast IP address or a unicast IP address. For this case, the IOPS AF identifies that the inner destination IP address is a group IP multicast address.12. The IOPS AF distributes the related IP packets over the IOPS MBMS bearer. For that, in this embodiment, the IP packets are transmitted over the corresponding TMGI/UDP port via the BM-SC, i.e. the IP packets are encapsulated within IP with an inner IP header including the group IP multicast address X and an outer IP header including the IP address of the BM-SC.13. MC UEs 2 and 3 receive and decode the IP packets addressed to the group IP multicast address X. MC UE 4 discards those related IP packets.14. The group call continues following the same described procedure.

MC Service Group Communication Support on the IOPS Mode of Operation Based on MBMS-Based Transmissions and/or Unicast Transmissions

As an enhanced embodiment, one or more IOPS MBMS bearers are pre-established or dynamically established on the IOPS mode of operation in order to support a more flexible MBMS implementation. Group communication sessions can be based on MBMS-based transmissions as well as unicast transmissions.

For that, the MC UEs publish group configuration (e.g. preconfigured UE's group IP multicast addresses) to the IOPS AF during the IOPS discovery procedure. Thereby, the IOPS AF obtains information about which IOPS groups a discovered UE belongs to, i.e. which group IP multicast address(es) a UE has been preconfigured with. Based on this, the IOPS AF can build a basic temporary user profile of discovered UEs including which IOPS groups the UEs may communicate with on the IOPS mode of operation.

Based on the received group configuration, the IOPS AF may decide to pre-establish or dynamically establish more than one IOPS MBMS bearer. Also, the IOPS AF may decide to distribute the group communication related IP packets based on either MBMS transmissions (over a corresponding IOPS MBMS bearer) or unicast transmissions or both.

In one embodiment, the IOPS AF may decide to pre-establish or dynamically establish one or more IOPS MBMS bearers considering, e.g., required MBMS bearer capacity and number of IOPS groups the IOPS AF has identified. For the later case, the IOPS AF may decide to establish an IOPS TMGI per identified IOPS group or an IOPS TMGI per a sub-set of IOPS groups. In a more efficient way, the IOPS AF may decide to dynamically establish a new IOPS MBMS bearer when the IOPS AF firstly identifies that an IP packet is targeting an IOPS group that hasn't been associated to an already established IOPS MBMS bearer yet.

In an additional embodiment, the IOPS AF can decide to initially pre-establish only an IOPS MBMS bearer, as described above in the section entitled “MC service group communication support on the IOPS mode of operation based on always MBMS-based transmissions”, and then decide to dynamically establish one or more IOPS MBMS bearers when required. Subsequently, the IOPS AF efficiently announces to the UEs which IOPS MBMS bearers need to be monitored.

Based on the group configuration the IOPS AF has received and the corresponding MBMS bearer configuration, i.e. the corresponding establishment of IOPS TMGIs, the IOPS AF announces to the UEs which TMGI(s) each UE should monitor to receive group communication related IP packets.

FIG.5

FIG.5is a schematic block diagram of a radio access node500according to some embodiments of the present disclosure. The radio access node500may be, for example, a base station202or206. As illustrated, the radio access node500includes a control system502that includes one or more processors504(e.g., Central Processing Units (CPUs), Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs), and/or the like), memory506, and a network interface508. The one or more processors504are also referred to herein as processing circuitry. In addition, the radio access node500includes one or more radio units510that each includes one or more transmitters512and one or more receivers514coupled to one or more antennas516. The radio units510may be referred to or be part of radio interface circuitry. In some embodiments, the radio unit(s)510is external to the control system502and connected to the control system502via, e.g., a wired connection (e.g., an optical cable). However, in some other embodiments, the radio unit(s)510and potentially the antenna(s)516are integrated together with the control system502. The one or more processors504operate to provide one or more functions of a radio access node500as described herein. In some embodiments, the function(s) are implemented in software that is stored, e.g., in the memory506and executed by the one or more processors504.

FIG.6

FIG.6is a schematic block diagram that illustrates a virtualized embodiment of the radio access node500according to some embodiments of the present disclosure. This discussion is equally applicable to other types of network nodes. Further, other types of network nodes may have similar virtualized architectures.

As used herein, a “virtualized” radio access node is an implementation of the radio access node500in which at least a portion of the functionality of the radio access node500is implemented as a virtual component(s) (e.g., via a virtual machine(s) executing on a physical processing node(s) in a network(s)). As illustrated, in this example, the radio access node500includes the control system502that includes the one or more processors504(e.g., CPUs, ASICs, FPGAs, and/or the like), the memory506, and the network interface508and the one or more radio units510that each includes the one or more transmitters512and the one or more receivers514coupled to the one or more antennas516, as described above. The control system502is connected to the radio unit(s)510via, for example, an optical cable or the like. The control system502is connected to one or more processing nodes600coupled to or included as part of a network(s)602via the network interface508. Each processing node600includes one or more processors604(e.g., CPUs, ASICs, FPGAs, and/or the like), memory606, and a network interface608.

In this example, functions610of the radio access node500described herein are implemented at the one or more processing nodes600or distributed across the control system502and the one or more processing nodes600in any desired manner. In some particular embodiments, some or all of the functions610of the radio access node500described herein are implemented as virtual components executed by one or more virtual machines implemented in a virtual environment(s) hosted by the processing node(s)600. As will be appreciated by one of ordinary skill in the art, additional signaling or communication between the processing node(s)600and the control system502is used in order to carry out at least some of the desired functions610. Notably, in some embodiments, the control system502may not be included, in which case the radio unit(s)510communicate directly with the processing node(s)600via an appropriate network interface(s).

In some embodiments, a computer program including instructions which, when executed by at least one processor, causes the at least one processor to carry out the functionality of radio access node500or a node (e.g., a processing node600) implementing one or more of the functions610of the radio access node500in a virtual environment according to any of the embodiments described herein is provided. In some embodiments, a carrier comprising the aforementioned computer program product is provided. The carrier is one of an electronic signal, an optical signal, a radio signal, or a computer readable storage medium (e.g., a non-transitory computer readable medium such as memory).

FIG.7

FIG.7is a schematic block diagram of the radio access node500according to some other embodiments of the present disclosure. The radio access node500includes one or more modules700, each of which is implemented in software. The module(s)700provide the functionality of the radio access node500described herein. This discussion is equally applicable to the processing node600ofFIG.6where the modules700may be implemented at one of the processing nodes600or distributed across multiple processing nodes600and/or distributed across the processing node(s)600and the control system502.

FIG.8

FIG.8is a schematic block diagram of a UE800according to some embodiments of the present disclosure. As illustrated, the UE800includes one or more processors802(e.g., CPUs, ASICs, FPGAs, and/or the like), memory804, and one or more transceivers806each including one or more transmitters808and one or more receivers810coupled to one or more antennas812. The transceiver(s)806includes radio-front end circuitry connected to the antenna(s)812that is configured to condition signals communicated between the antenna(s)812and the processor(s)802, as will be appreciated by on of ordinary skill in the art. The processors802are also referred to herein as processing circuitry. The transceivers806are also referred to herein as radio circuitry. In some embodiments, the functionality of the UE800described above may be fully or partially implemented in software that is, e.g., stored in the memory804and executed by the processor(s)802. Note that the UE800may include additional components not illustrated inFIG.8such as, e.g., one or more user interface components (e.g., an input/output interface including a display, buttons, a touch screen, a microphone, a speaker(s), and/or the like and/or any other components for allowing input of information into the UE800and/or allowing output of information from the UE800), a power supply (e.g., a battery and associated power circuitry), etc.

In some embodiments, a computer program including instructions which, when executed by at least one processor, causes the at least one processor to carry out the functionality of the UE800according to any of the embodiments described herein is provided. In some embodiments, a carrier comprising the aforementioned computer program product is provided. The carrier is one of an electronic signal, an optical signal, a radio signal, or a computer readable storage medium (e.g., a non-transitory computer readable medium such as memory).

FIG.9

FIG.9is a schematic block diagram of the UE800according to some other embodiments of the present disclosure. The UE800includes one or more modules900, each of which is implemented in software. The module(s)900provide the functionality of the UE800described herein.

Some Embodiments

Some embodiments that are described above may be summarized in the following manner:1. A method performed by an IOPS application function, AF, to provide a group communication service, the method comprising:establishing (FIG.4A, step4) an IOPS MBMS bearer, the IOPS MBMS bearer being an MBMS bearer within a MBSFN area served by one or more radio access nodes that are operating in an IOPS mode of operation;discovering (FIG.4A, step6) one or more User Equipments, UEs, via an IOPS discovery procedure;sending (FIG.4A, step7), to the one or more UEs, an MBMS bearer announcement for the IOPS MBMS bearer.2. The method of embodiment 1 further comprising:receiving (FIG.4A, step10) an IP packet from a UE via one of the one or more radio access nodes that are operating in the IOPS mode of operation;determining (FIG.4B, step11) that the IP packet is for a group communication service;upon determining (FIG.4B, step11) that the IP packet is for the group communication service, sending (FIG.4B, step12) the IP packet over the IOPS MBMS bearer.3. The method of embodiment 2 wherein all IP packets related to group communication sessions are sent over the IOPS MBMS bearer.4. The method of embodiment 3 wherein sending (FIG.4B, step12) the IP packet over the IOPS MBMS bearer comprises sending (FIG.4B, step12) the IP packet over the IOPS MBMS bearer using an outer IP header with a BM-SC IP address and UDP port associated to a corresponding TMGI.5. The method of any one of embodiments 2 to 4 wherein determining (FIG.4B, step11) that the IP packet is for the group communication service comprises:determining that an IP address of an actual IP address of the IP packet is a multi-cast IP address.6. The method of embodiment 5 wherein the actual IP address of the IP packet is an IP address contained within an inner IP header of the IP packet, wherein the IP packet comprises:the inner IP header comprising the actual IP address of the IP packet; andan outer IP header comprising an IP address associated with the IOPS MBMS bearer (e.g., a BM-SC IP address and UDP port associated to a corresponding TMGI).7. The method of any one of embodiments 1 to 6 wherein establishing (FIG.4A, step4) the IOPS MBMS bearer comprises pre-establishing (FIG.4A, step4) the IOPS MBMS bearer upon initiation of the IOPS mode of operation.8. The method of any one of embodiments 1 to 7 wherein the MBMS bearer announcement indicates that one or more group communication sessions for the group communication service are transmitted over the IOPS MBMS bearer.9. The method of any one of embodiments 1 to 8 wherein the one or more UEs do not publish any user group information to the IOPS AF during the IOPS discovery procedure.10. The method of embodiment 7 further comprising pre-establishing one or more additional IOPS MBMS bearers.11. The method of embodiment 10 wherein the IOPS MBMS bearer and the one or more additional IOPS MBMS bearers are pre-established based on group configuration information obtained from the one or more UEs during the IOPS discovery procedure.12. The method of embodiment 10 wherein the IOPS MBMS bearer and the one or more additional IOPS MBMS bearers are pre-established based on group configuration information obtained from the one or more UEs during the IOPS discovery procedure and one or more additional criteria (e.g., required MBMS bearer capacity, number of IOPS groups, or both).13. The method of any one of embodiments 1 to 9 further comprising dynamically establishing one or more additional IOPS MBMS bearers.14. The method of any one of embodiments 1 to 9 further comprising:receiving additional IP packets with different multicast IP addresses; anddynamically establishing one or more additional IOPS MBMS bearers based on the different multicast IP addresses.15. The method of any one of embodiments 10 to 11 further, to the one or more UEs, one or more additional MBMS bearer announcements for the one or more additional IOPS MBMS bearers.16. A network node that implements an IOPS application function, AF, for providing a group communication service, the network node adapted to perform the method of any one of embodiments 1 to 15.17. A method performed by User Equipment, UE, for group communication in an IOPS system, the method comprising:performing (FIG.4A, step6) an IOPS discovery procedure by which an IOPS AF discovers the UE;receiving (FIG.4A, step7), from the IOPS AF, an MBMS bearer announcement for an IOPS MBMS bearer, the IOPS MBMS bearer being an MBMS bearer within a MBSFN area served by one or more radio access nodes that are operating in an IOPS mode of operation.18. The method of embodiment 17 further comprising receiving (FIG.4B, step12,13A,13B) an IP packet for a group communication session from the IOPS AF over the IOPS MBMS bearer.19. The method embodiment 18 wherein all IP packets related to group communication sessions are sent over the IOPS MBMS bearer.20. The method of embodiment 18 or 19 further comprising:determining that the IP packet is addressed to a particular multicast address for a particular group communication session being monitored by the UE; andupon determining that the IP packet is addressed to the particular multicast address for the particular group communication session being monitored by the UE, decoding (FIG.4B, step13A) the IP packet.21. The method of embodiment 18 or 19 further comprising:determining that the IP packet is addressed to a particular multicast address for a particular group communication session that is not being monitored by the UE; andupon determining that the IP packet is addressed to the particular multicast address for the particular group communication session that is not being monitored by the UE, discarding (FIG.4B, step13B) the IP packet.22. The method of any one of embodiments 17 to 21 wherein the MBMS bearer announcement indicates that one or more group communication sessions for the group communication service are transmitted over the lops MBMS bearer.23. The method of any one of embodiments 17 to 22 wherein the UE does not publish any user group information to the IOPS AF during the IOPS discovery procedure.24. The method of any one of embodiments 17 to 22 wherein the UE does publish user group information to the IOPS AF during the IOPS discovery procedure.25. A User Equipment, UE, adapted to perform the method of any one of embodiments 17 to 24.

Any appropriate steps, methods, features, functions, or benefits disclosed herein may be performed through one or more functional units or modules of one or more virtual apparatuses. Each virtual apparatus may comprise a number of these functional units. These functional units may be implemented via processing circuitry, which may include one or more microprocessor or microcontrollers, as well as other digital hardware, which may include Digital Signal Processor (DSPs), special-purpose digital logic, and the like. The processing circuitry may be configured to execute program code stored in memory, which may include one or several types of memory such as Read Only Memory (ROM), Random Access Memory (RAM), cache memory, flash memory devices, optical storage devices, etc. Program code stored in memory includes program instructions for executing one or more telecommunications and/or data communications protocols as well as instructions for carrying out one or more of the techniques described herein. In some implementations, the processing circuitry may be used to cause the respective functional unit to perform corresponding functions according one or more embodiments of the present disclosure.

While processes in the figures may show a particular order of operations performed by certain embodiments of the present disclosure, it should be understood that such order is exemplary (e.g., alternative embodiments may perform the operations in a different order, combine certain operations, overlap certain operations, etc.).

Abbreviations

At least some of the following abbreviations may be used in this disclosure. If there is an inconsistency between abbreviations, preference should be given to how it is used above. If listed multiple times below, the first listing should be preferred over any subsequent listing(s).2G Second Generation3G Third Generation3GPP Third Generation Partnership Project4G Fourth Generation5G Fifth GenerationAF Application FunctionAMF Access and Mobility Management FunctionAN Access NetworkAP Access PointAUSF Authentication Server FunctionBS Base StationBSC Base Station ControllerBTS Base Transceiver StationCDMA Code Division Multiple AccessCGI Cell Global IdentifierDL DownlinkDN Data NetworkECGI Evolved Cell Global IdentifiereNB Enhanced or Evolved Node BEPC Evolved Packet CoreEPS Evolved Packet SystemE-UTRA Evolved Universal Terrestrial Radio AccessE-UTRAN Evolved Universal Terrestrial Radio Access NetworkGC Group CommunicationGERAN Global System for Mobile (GSM) Communications Enhanced Data Rates for GSM Evolution Radio Access NetworkgNB New Radio Base StationGSM Global System for Mobile CommunicationsHO HandoverHSPA High Speed Packet AccessIOPS Isolated Evolved Universal Terrestrial Radio Access Network Operations for Public SafetyIP Internet ProtocolLAN Local Area NetworkLTE Long Term EvolutionMAC Medium Access ControlMBMS Multimedia Broadcast Multicast ServicesMBSFN Multimedia Broadcast Multicast Service Single Frequency NetworkMC Mission CriticalMIB Master Information BlockMME Mobility Management EntityMSC Mobile Switching CenterNEF Network Exposure FunctionNF Network FunctionNFV Network Function VirtualizationNR New RadioNRF Network Function Repository FunctionNSSF Network Slice Selection FunctionO&M Operation and MaintenanceOSS Operations Support SystemPCF Policy Control FunctionP-GW Packet Data Network GatewayPLMN Public Land Mobile NetworkPRB Physical Resource BlockPSTN Public Switched Telephone NetworksPTT Push to TalkQoS Quality of ServiceRAN Radio Access NetworkRAT Radio Access TechnologySCEF Service Capability Exposure FunctionSDU Service Data UnitS-GW Serving GatewaySI System InformationSIB System Information BlockSIM Subscriber Identity ModuleSMF Session Management FunctionTCP Transmission Control ProtocolTMGI Temporary Mobile Group IdentityUDM Unified Data ManagementUE User EquipmentUL UplinkUMTS Universal Mobile Telecommunications SystemUSIM Universal Subscriber Identity ModuleUTRA Universal Terrestrial Radio AccessUTRAN Universal Terrestrial Radio Access NetworkVNE Virtual Network ElementVNF Virtual Network FunctionVoIP Voice over Internet ProtocolWCDMA Wideband Code Division Multiple AccessWD Wireless Device