Patent Publication Number: US-2023156839-A1

Title: Methods and Apparatus for Connection Setup of Sidelink Relays

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of International Application No. PCT/US2021/044539, filed Aug. 4, 2021, entitled “Methods and Apparatuses for Connection Setup of Sidelink Relays,” which claims the benefit of U.S. Provisional Application No. 63/061,547, filed on Aug. 5, 2020, entitled “Methods and Apparatus for Protocol Stack and Connection Setup of Sidelink Relay,” which application is hereby incorporated herein by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates generally to methods and apparatus for digital communications, and, in particular embodiments, to methods and apparatus for connection setup of sidelink relays. 
     BACKGROUND 
     In general, a user equipment (UE) can be in direct communication with a radio access network (RAN). The UE may also be in sidelink communication with another UE. If the UE is out of coverage of the RAN, the UE cannot communicate with the RAN. However, a UE that is in direct communication with the RAN can serve as a relay UE for the UE that is out of coverage of the RAN. In other words, the relay UE allows the UE to have indirect communication with the RAN, with the relay UE serving as intermediary between the UE and the RAN. The relay UE in this situation is referred to as a sidelink relay. 
     There is a need for methods and apparatus for connection setup of sidelink relays. 
     SUMMARY 
     An advantage of a preferred embodiment is that a first UE within RAN coverage can support communication for a second UE over a sidelink connection between the two UEs. The sidelink connection also provides support for QoS requirements. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a more complete understanding of the present disclosure, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which: 
         FIG.  1    illustrates a first example communications system; 
         FIG.  2    illustrates a communication system highlighting a UE to network connection supported by a relay UE; 
         FIG.  3    illustrates an example user plane (UP) protocol stack of an example communication system; 
         FIG.  4    illustrates an example control plane (CP) protocol stack of an example communication system; 
         FIG.  5    illustrates protocol stack of an example communication system with a Layer-3 sidelink relay; 
         FIG.  6    illustrates a diagram of communications exchanged and processing performed by entities involved in an example connection setup procedure for UE to network relay according to example embodiments presented herein; 
         FIG.  7    illustrates a flow diagram of example operations occurring in a remote UE participating in the establishment of a UE to network relay connection according to example embodiments presented herein; 
         FIG.  8    illustrates a flow diagram of example operations occurring in a relay UE participating in the establishment of a UE to network relay connection according to example embodiments presented herein; 
         FIG.  9    illustrates a flow diagram of example operations occurring in a serving access node participating in the establishment of a UE to network relay connection according to example embodiments presented herein; 
         FIG.  10    illustrates a flow diagram of example operations occurring in a network control function participating in the establishment of a UE to network relay connection according to example embodiments presented herein; 
         FIG.  11    illustrates an example communication system according to example embodiments presented herein; 
         FIGS.  12 A and  12 B  illustrate example devices that may implement the methods and teachings according to this disclosure; 
         FIG.  13    is a block diagram of a computing system that may be used for implementing the devices and methods disclosed herein; 
         FIG.  14    illustrates a block diagram of an embodiment processing system for performing methods described herein, which may be installed in a host device; and 
         FIG.  15    illustrates a block diagram of a transceiver adapted to transmit and receive signaling over a telecommunications network according to example embodiments presented herein. 
     
    
    
     DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS 
     The structure and use of disclosed embodiments are discussed in detail below. It should be appreciated, however, that the present disclosure provides many applicable concepts that can be embodied in a wide variety of specific contexts. The specific embodiments discussed are merely illustrative of specific structure and use of embodiments, and do not limit the scope of the disclosure. 
       FIG.  1    illustrates a first example communications system  100 . Communications system  100  includes an access node  110 , with coverage area  101 , serving user equipments (UEs), such as UEs  120 . Access node  110  is connected to a backhaul network  115  that provides connectivity to services and the Internet. In a first operating mode, communications to and from a UE passes through access node  110 . In a second operating mode, communications to and from a UE do not pass through access node  110 , however, access node  110  typically allocates resources used by the UE to communicate when specific conditions are met. Communication between a UE pair in the second operating mode occurs over sidelinks  125 , comprising device-to-device or peer-to-peer communication links. Communication between a UE and access node pair also occur over uni-directional communication links, where the communication links between the UE and the access node are referred to as uplinks  130 , and the communication links between the access node and UE is referred to as downlinks  135 . 
     Access nodes may also be commonly referred to as Node Bs, evolved Node Bs (eNBs), next generation (NG) Node Bs (gNBs), master or primary eNBs (MeNBs), secondary eNBs (SeNBs), master or primary gNBs (MgNBs), secondary gNBs (SgNBs), network controllers, control nodes, base stations, access points, transmission points (TPs), transmission-reception points (TRPs), cells, carriers, macro cells, femtocells, pico cells, and so on, while UEs may also be commonly referred to as mobile stations, mobiles, terminals, users, subscribers, stations, and the like. Access nodes may provide wireless access in accordance with one or more wireless communication protocols, e.g., the Third Generation Partnership Project (3GPP) long term evolution (LTE), LTE advanced (LTE-A), 5G, 5G LTE, 5G NR, sixth generation (6G), High Speed Packet Access (HSPA), the IEEE 802.11 family of standards, such as 802.11a/b/g/n/ac/ad/ax/ay/be, etc. While it is understood that communications systems may employ multiple access nodes capable of communicating with a number of UEs, only one access node and two UEs are illustrated for simplicity. 
       FIG.  2    illustrates a communication system  200  highlighting a UE to network connection supported by a relay UE. Communication system  200  has a coverage area  201 . Communication system  200  includes an access node  205  that is serving a first UE  210 . Also shown in  FIG.  2    is a second UE  215 . Second UE  215  is outside of coverage area  201  of communication system  201 , hence second UE  215  is unable to connect to access node  205 . First UE  210  is capable of operating as a relay UE. 
     Second UE  215  connects with first UE  210  through a PC5 interface  217  over a sidelink. First UE  210  is operating in this situation as a relay UE and is referred to as such. Furthermore, second UE  215  is operating as a remote UE and is referred to as such. Relay UE  210  is connected to access node  205  through a Uu interface  219 . Hence, relay UE  210  is able to pass packets received from remote UE  215  to access node  205  on the uplink. Conversely, relay UE  210  is able to forward packets received from access node  205  to remote UE  215 . In this way, an indirect connection path is established between remote UE  215  and access node  205 , with the help of relay UE  210 . 
     In 3GPP RP-193253, “New SID: Study on NR sidelink relay,” which is hereby incorporated herein by reference in its entirety, specifies “For layer-2 UE-to-network relay, the architecture of end-to-end packet data convergence protocol (PDCP) and hop-by-hop radio link control (RLC), e.g., as recommended in TR36.746, is taken as starting point.” 
       FIG.  3    illustrates an example user plane (UP) protocol stack  300  of an example communication system. UP protocol stack  300  includes entities at remote UE  215 , relay UE  210 , access node  205 , and user plane function (UPF) 305 . An entity at adaptation layer  310  of relay UE  210  resides on top of PC5 RLC entity  315  and Uu RLC entity  316  of relay UE  210 , where the packets of remote UE  215  carried in RLC channel from remote UE  215  to relay UE  210  is mapped to an RLC channel from relay UE  210  to access node  205 , and vice versa. Similarly, Adaptation layer  311  of access node  205  resides on top of RLC entity  317  of access node  205 , where adaptation layer  311  maps the packets of remote UE  215  carried in RLC channel from relay UE  210  to access node  205  to remote UE&#39;s radio bearer, and vice versa. Because adaptation layers  310  and  311  apply to RLC channels of all radio bearers, adaptation layers  310  and  311  support both signaling radio bearers (SRBs) and data radio bearers (DRBs) of remote UE  215 . 
       FIG.  4    illustrates an example control plane (CP) protocol stack  400  of an example communication system. CP protocol stack  400  includes entities at remote UE  215 , relay UE  210 , access node  205 , and access and mobility management function (AMF) 405 . An adaptation layer  410  of relay UE  210  resides on top of RLC entity  415  and  416  of relay UE  210 , where an entity at adaptation layer map the packets of remote UE  215  between RLC channel of remote UE  215  and an RLC channel of relay UE  210 . Similarly, an entity of adaptation layer  411  of access node  205  resides on top of RLC layer  417  of access node  205 , where the packets of a radio bearer of remote UE  215  is mapped to or from RLC channel  417  between relay UE  210  and access node  205 . Because entities at adaptation layers  410  and  411  apply to RLC channels of all radio bearers, entities at adaptation layers  410  and  411  support both SRBs and DRBs of remote UE  215 . 
     In general, a Layer-3 sidelink relay can relay unicast traffic (uplink and downlink) between the remote UE and the network (as specified in 3GPP TR 23.752, which is hereby incorporated by reference in its entirety) for:
         Internet Protocol (IP) traffic over a PC5 interface reference point, the ProSe UE-to-Network relay uses IP type protocol data unit (PDU) sessions towards the Fifth Generation core (5GC).   Ethernet traffic over a PC5 interface reference point, the ProSe UE-to-Network relay can use Ethernet type PDU sessions or IP type PDU sessions towards the 5GC.   Unstructured traffic over a 5GC interface reference point, the ProSe UE-to-Network relay can use unstructured type PDU sessions or IP type PDU sessions (i.e., IP encapsulation or de-capsulation by the UE-to-Network relay) towards the 5GC.       

       FIG.  5    illustrated protocol stack  500  of an example communication system with a Layer-3 sidelink relay. The communication system includes remote UE  215 , relay UE  210  (which is the Layer-3 sidelink relay), access node  205 , and a UPF  505 . 
     In the Layer-3 UE-to-Network relay approach, a 5G Quality of Service (QoS) flow is initially mapped to a PC5 QoS flow for sidelink transmission, then the PC5 QoS flow is mapped to the 5G QoS flow of relay UE  210  for transmission over the Uu interface. Finally, the 5G QoS flow of relay UE  210  is mapped back to the 5G QoS flow associated with remote UE  215  at UPF  505 . The mapping of the flows occur in the adaptation layer, such as adaptation layer  507  of remote UE  215 , adaptation layer  509  of relay UE  210 , and adaptation layer  511  of UPF  505 . 
     Because the Layer-3 sidelink relay operates at the level of PDU connections, the Layer-3 sidelink relay does not relay control plane data between remote UE  215  and access node  205  through relay UE  210 . On the other hand, the Layer-2 sidelink relay operates at the level of RLC channels, and is agnostic to SRBs or DRBs. Therefore, both control plane and data plane data for remote UE  215  and access node  205  can be relayed by relay UE  210 . 
     According to an example embodiment, methods and apparatus for indirect connection setup between a remote UE and an access node are provided. A relay UE serves as a sidelink relay, relaying both control plane and user plane data between the remote UE and the access node. A variety of techniques may be used to setup the indirect connection. As an example, sidelink unicast communications may be used. 
       FIG.  6    illustrates a diagram  600  of communications exchanged and processing performed by entities involved in an example connection setup procedure for UE to network relay. The entities exchanging communications and performing processing include a remote UE  605 , a relay UE  607 , a serving access node  609 , an AMF/session management function (SMF)/policy control function (PCF)  611 , and a UPF  613 .  FIG.  6    illustrates the connection setup procedure for both Layer-2 and Layer-3 sidelink relay models. 
     For both Layer-2 and Layer-3 sidelink relay models,
         A PC5 RRC connection is needed to configure a sidelink bearer for unicast transmission between remote UE  605  and relay UE  607 .   A RRC connection between relay UE  607  and the RAN is involved for the RAN to provide to relay UE  607  the sidelink bearer configuration for the PC5 segment of the UE to network relay connection.       

     The RRC connection between relay UE  607  and the RAN also configures the adaptation layer in the Layer-2 sidelink relay model. 
     Discovery and authorization of relay UE  607  is performed (block  615 ). Remote UE  605 , serving access node  609 , AMF/SMF/PCF  611 , and relay UE  607  perform discovery and authorization to discover a relay UE (i.e., relay UE  607 ) that is a suitable relay for remote UE  605 , as well as authorized to serve as a relay UE for remote UE  605 . In both the Layer-2 and Layer-3 relay UE models, the discovery and authorization of relay UE  607  includes the authorization of relay UE  607 . Furthermore, remote UE  605  is provided with information associated with serving access node  609 , including the public land mobile network (PLMN) identity and cell identity of serving access node  609 . 
     Relay UE  607  and remote UE  605  establish a PC5 RRC connection (block  617 ). The PC5 RRC connection supports unicast communications between remote UE  605  and relay UE  607 , for example. As an example, the establishment of the PC5 RRC connection is accomplished by relay UE  607  and remote UE  605  exchanging messaging. 
     After successfully discovering and authorizing relay UE  607 , remote UE  605  sends a UE to network connection setup request to relay UE  607  (event  619 ). Remote UE  605  requests the establishment of the UE to network relay by sending a request to relay UE  607 . The request includes information, such as the PLMN of serving access node  609  and the identity of remote UE  605 . In the case of the Layer-3 relay model, remote UE  605  also provides information regarding the PC5 QoS flow to be used for the UE to network relay. Relay UE  607  forwards the request to serving access node  609  (event  621 ). Relay UE  607  forwards the request, along with the information included therein (e.g., the PLMN of serving access node  609  and the identity of remote UE  605 ), to serving access node  609 . 
     Serving access node  609  and AMF/SMF/PCF  611  perform admission control (block  623 ). Serving access node  609  and AMF/SMF/PCF  611  perform policy check and admission control to allow the indirect 5G connection of remote UE  605  through relay UE  607 . The policy check and admission control are performed based on information associated with remote UE  605  and relay UE  607 . In the case of the Layer-2 relay model, serving access node  609  is also provided with the QoS information of remote UE  605 . 
     Serving access node  609  sends a relay UE setup response to relay UE  607  (event  625 ). Serving access node  609  provides relay UE  607  with an RLC configuration of a remote UE&#39;s DRB over a PC5 interface between remote UE  605  and relay UE  607 . In the case of the Layer-2 relay model, the serving access node  609  also provides relay UE  607  with an adaptation configuration to map RLC channels of the Uu interface between relay UE  607  and serving access node  609 , and the PC5 interface between remote UE  605  and relay UE  607 , as well as a container of DRB configurations of remote UE  605 . The DRB configurations may include service data application protocol (SDAP) and PDCP configurations, including the mapping of 5G QoS flows to DRBs. In the case of Layer-3 relay model, the serving access node  609  also provides relay UE  607  with SDAP and PDCP configurations of sidelink DRBs over the PC5 interface between remote UE  605  and relay UE  607 , including the PC5 QoS flow to DRB mappings. 
     Dashed box  627  illustrates the control plane and user plane connections for remote UE  607  present in the Layer-2 relay model. Dashed box  629  illustrates the user plane connection for remote UE  607  in the Layer-3 relay model. The control plane and user plane connections currently stop at relay UE  607 . 
     Relay UE  607  sends a UE to network relay setup response to remote UE  605  (event  631 ). Relay UE  607  configures RLC entities of the sidelink bearers. In the case of the Layer-2 relay model, relay UE  607  also forwards the signaling container of bearer configurations of remote UE  605  to remote UE  605 . The signaling container of bearer configurations includes, for example, SDAP and PDCP configurations, including the mapping of 5G QoS flows to DRBs. In the case of the Layer-3 relay model, relay UE  607  configures remote UE  605  with SDAP and PDCP configurations of sidelink DRBs over the PC5 interface between remote UE  605  and relay UE  607 , including the PC5 QoS flow to DRB mappings. 
     Remote UE  605  sends UE to network relay setup complete message to relay UE  607  (event  633 ). After establishing the RLC entities of the sidelink bearers, remote UE  605  provides confirmation of the establishment to relay UE  607 . Remote UE  605  may also update the RLC configuration of the sidelink bearers. In the case of the Layer-2 relay model, remote UE  605  also provides to the relay UE  607  signaling containing the confirmation of the proper configuration of SDAP and PDCP entities of the UE to network DRBs. In the case of the Layer-3 relay model, remote UE  605  also provides to relay UE  607  the confirmation of the SDAP and PDCP configuration of the sidelink DRBs. Remote UE  605  may also provide possible updates of the SDAP and PDCP configurations of sidelink bearers. 
     Relay UE  607  forwards the relay UE setup complete message to serving access node  609  (event  635 ). Relay UE  607  informs serving access node  609  that the sidelink RLC channels have been established for the UE to network relay, for example. In the case of the Layer-2 relay model, relay UE  607  also informs serving access node  609  that the mapping between the sidelink RLC channels and Uu RLC channel carrying remote UE&#39;s same packets for the adaptation layer has been established. Relay UE  607  also forwards the container of confirmations of proper configuration of SDAP and PDCP entities of the UE to network bearers. In the case of the Layer-3 relay model, relay UE  607  also informs serving access node  609  that SDAP and PDCP entities have been established for the sidelink bearers. 
     Dashed box  637  illustrates the control plane and user plane connections for remote UE  607  present in the Layer-2 relay model. Dashed box  639  illustrates the user plane connection for remote UE  607  in the Layer-3 relay model. The control plane and user plane connections extend all the way to remote UE  605 . 
     
       
         
           
               
             
               
                 TABLE 1 
               
             
            
               
                   
               
               
                 Procedural steps in Layer-2 and Layer-3 relay UE connection setup. 
               
               
                 Table 1 provides a detailed listing of procedural steps in the example connection 
               
               
                 setup procedure for UE to network relay for both Layer-2 and Layer-3 relay models. 
               
            
           
           
               
               
               
            
               
                   
                 Layer-2 Relay 
                 Layer-3 Relay 
               
               
                   
               
            
           
           
               
               
            
               
                 1. Relay UE Discovery 
                 The relay UE is authorized, and provides the remote UE with 
               
               
                 and Authorization 
                 information of the serving access node, e.g., its PLMN and cell 
               
               
                   
                 identities. 
               
               
                 2. PC5 RRC Connection 
                 PC5 RRC connection is established between the remote UE and 
               
               
                 Establishment 
                 relay UE for unicast communication. 
               
               
                 3. UE to Network 
                 The remote UE requests the establishment of UE to network 
               
               
                 connection Setup 
                 connection, and provides information, such as the selected PLMN, 
               
               
                 Request 
                 and its identity. 
               
            
           
           
               
               
               
            
               
                   
                   
                 The remote UE also provides 
               
               
                   
                   
                 the information of PC5 QoS 
               
               
                   
                   
                 flow to be used for UE to 
               
               
                   
                   
                 network relay. 
               
            
           
           
               
               
            
               
                 4- Relay UE Setup 
                 The relay UE forwards the remote UE’s request and information to 
               
               
                 Request 
                 the serving access node. 
               
               
                 5. Admission Control 
                 Based on the information of the remote UE and relay UE, the 
               
               
                   
                 serving access node and access and mobility management, session 
               
               
                   
                 management, and policy control functions (AMF/SMF/PCF) in 
               
               
                   
                 network perform policy check and admission control to allow the 
               
               
                   
                 indirect 5G connection of the remote UE through the relay UE. 
               
            
           
           
               
               
               
            
               
                   
                 The serving access node is 
                   
               
               
                   
                 provided with QoS flow 
                   
               
               
                   
                 information of the remote UE. 
                   
               
            
           
           
               
               
            
               
                 6. Relay UE Setup 
                 The serving access node provides the relay UE with RLC 
               
               
                   
                 configuration over PC5 interface between the remote UE and the 
               
               
                   
                 relay UE. 
               
            
           
           
               
               
               
            
               
                   
                 The serving access node also 
                 The serving access node also 
               
               
                   
                 provides the relay UE with 
                 provides the relay UE with 
               
               
                   
                 adaptation configuration to map 
                 SDAP and PDCP 
               
               
                   
                 RLC channels of Uu interface 
                 configurations of sidelink 
               
               
                   
                 (between the relay UE and the 
                 DRBs over the PC5 interface 
               
               
                   
                 serving access node) and PC5 
                 between the remote UE and 
               
               
                   
                 interface (between the remote UE 
                 the relay UE, including the 
               
               
                   
                 and the relay UE) for remote UE’s 
                 PC5 QoS flow to DRB 
               
               
                   
                 packets, and a signaling 
                 mapping. 
               
               
                   
                 containing radio bearer 
                   
               
               
                   
                 configurations of the remote UE, 
                   
               
               
                   
                 such as SDAP and PDCP 
                   
               
               
                   
                 configurations, including the 
                   
               
               
                   
                 mapping of 5G QoS flow to DRB. 
                   
               
            
           
           
               
               
            
               
                 7. UE to Network Relay 
                 The relay UE configures RLC entities of sidelink bearers. 
               
            
           
           
               
               
               
            
               
                 Setup 
                 The relay UE also forwards to the 
                 The relay UE configures the 
               
               
                   
                 remote UE the signaling 
                 remote UE with SDAP and 
               
               
                   
                 containing radio bearer 
                 PDCP configurations of 
               
               
                   
                 configurations of the remote UE, 
                 sidelink DRBs over the PC5 
               
               
                   
                 such as SDAP and PDCP 
                 interface between the remote 
               
               
                   
                 configurations, including the 
                 UE and the relay UE, 
               
               
                   
                 mapping of 5G QoS flow to DRB. 
                 including the PC5 QoS flow 
               
               
                   
                   
                 to DRB mapping. 
               
            
           
           
               
               
            
               
                 8. UE to Network Relay 
                 After establishing RLC entities of sidelink radio bearers, the 
               
               
                 Setup Complete 
                 remote UE provides the relay UE confirmation and possible 
               
               
                   
                 updates of RLC configuration of sidelink radio bearers. 
               
            
           
           
               
               
               
            
               
                   
                 The remote UE also provides the 
                 The remote UE also provides 
               
               
                   
                 relay UE with a signaling 
                 the relay UE confirmation 
               
               
                   
                 containing confirmation of proper 
                 and possible updates of 
               
               
                   
                 configuration of SDAP and PDCP 
                 SDAP and PDCP 
               
               
                   
                 entities of UE to network radio 
                 configuration of sidelink 
               
               
                   
                 bearers. 
                 DRBs. 
               
            
           
           
               
               
            
               
                 9. Relay UE Setup 
                 The relay UE informs the serving gNB that sidelink RLC channels 
               
               
                 Complete 
                 have been established for UE to network relay. 
               
            
           
           
               
               
               
            
               
                   
                 The relay UE also informs the 
                 The relay UE also informs the 
               
               
                   
                 serving access node the mapping 
                 serving access node that 
               
               
                   
                 is established between the sidelink 
                 SDAP and PDCP entities 
               
               
                   
                 RLC channel and Uu RLC channel 
                 have been established for 
               
               
                   
                 carrying remote UE’s packets of 
                 sidelink DRBs. 
               
               
                   
                 respective radio bearers for the 
                   
               
               
                   
                 adaptation layer. The relay UE 
                   
               
               
                   
                 forwards the signaling containing 
                   
               
               
                   
                 confirmation of proper 
                   
               
               
                   
                 configuration of SDAP and PDCP 
                   
               
               
                   
                 entities of UE to network radio 
                   
               
               
                   
                 bearers. 
               
               
                   
               
            
           
         
       
     
     Although a UE to network relay connection may be established as described above for both Layer-2 and Layer-3 relay models, the remote UE served by the Layer-2 relay establishes both control plane and user plane connections with the serving access node and enter a RRC Connected state, while the remote UE served by the Layer-3 relay does not establish presence in the RAN. 
     Furthermore, when the UE to network relay setup procedures presented above conclude, the Layer-2 relay can already operate its adaptation layer with proper configuration of RLC channel mapping between PC5 and Uu interfaces. 
       FIG.  7    illustrates a flow diagram of example operations  700  occurring in a remote UE participating in the establishment of a UE to network relay connection. Operations  700  may be indicative of operations occurring in a remote UE as the remote UE participates in the establishment of a UE to network relay connection. Layer-2 and Layer-3 relay model connections may be established. 
     Operations  700  begin with the remote UE performing relay UE discovery and authorization (block  705 ). Relay UE discovery and authorization is performed to detect relay UEs that are suitable candidates for operation as a relay UE for the remote UE. As an example, in order to be a suitable candidate for operation as a relay UE for the remote UE, a relay UE may need to be located within a specified distance to the remote UE (or a channel between the remote UE and the remote UE has adequate signal quality), as well as the relay UE being amenable to serving as a relay UE for the remote UE and the relay UE be authorized to serve as a relay UE for the remote UE. As part of the relay UE discovery and authorization, the remote UE is provided with information related to the serving access node (e.g., the PLMN and cell identities of the serving access node). 
     The remote UE establishes a RRC connection (block  707 ). The RRC connection is established between the remote UE and the relay UE. The RRC connection supports unicast communication, for example. The remote UE sends a UE to network relay connection setup request (block  709 ). The UE to network relay connection setup request is a request for the establishment of the UE to network relay connection sent over an RLC channel over sidelink. The request includes information that includes a PLMN selected by the remote UE, as well as the identity of the remote UE. In the case of the Layer-3 relay model, the request also includes information regarding the PC5 QoS flow to be used for the UE to network relay connection. 
     The remote UE receives a UE to network relay setup response (block  711 ). The UE to network setup response may indicate to the remote UE that the UE to network relay setup is complete. The response may be received from the relay UE, where the relay UE has configured RLC entities of the sidelink radio bearers. In the case of the Layer-2 relay model, the remote UE also receives a signaling containing bearer configurations, which includes SDAP and PDCP configurations, such as the mappings of 5G QoS flows to DRBs. In the case of the Layer-3 relay model, the remote UE is configured with SDAP And PDCP configurations of the sidelink DRBs over the PC5 interface between the remote UE and the relay UE. The configurations may include the PC5 QoS flow to DRB mappings. 
     The remote UE sends a UE to network relay setup complete (block  713 ). The remote UE provides the relay UE with confirmation of the completion of the UE to network relay setup. The remote UE may also provide updates of the RLC configuration of the sidelink bearers. In the Layer-2 relay model, the remote UE also provides the relay UE with a signaling containing confirmation of the proper configuration of SDAP and PDCP entities of the UE to network bearers. In the Layer-3 relay model, the remote UE also provides the relay UE the confirmation (along with possible updates) of the SDAP and PDCP configuration of sidelink DRBs. 
       FIG.  8    illustrates a flow diagram of example operations  800  occurring in a relay UE participating in the establishment of a UE to network relay connection. Operations  800  may be indicative of operations occurring in a relay UE as the relay UE participates in the establishment of a UE to network relay connection. Layer-2 and Layer-3 relay model connections may be established. 
     Operations  800  begin with the relay UE performing relay UE discovery and authorization (block  805 ). Relay UE discovery and authorization is performed to identify relay UEs that are suitable candidates for operation as a relay UE for a remote UE. As an example, in order to be a suitable candidate for operation as a relay UE for the remote UE, a relay UE may need to be located within a specified distance to the remote UE (or a channel between the remote UE and the remote UE has adequate signal quality), as well as the relay UE being amenable to serving as a relay UE for the remote UE and the relay UE be authorized to serve as a relay UE for the remote UE. As part of the relay UE discovery and authorization, the relay UE provides information related to the serving access node (e.g., the PLMN and cell identities of the serving access node). 
     The relay UE establishes a RRC connection (block  807 ). The RRC connection is established between the remote UE and the relay UE. The RRC connection supports unicast communication, for example. The relay UE receives a UE to network relay connection setup request (block  809 ). The relay UE receives the UE to network relay connection setup request from the remote UE. The UE to remote relay connection setup request is a request for the establishment of the UE to network relay connection. The request includes information that includes a PLMN information received by the remote UE from the relay UE, as well as the identity of the remote UE. In the case of the Layer-3 relay model, the request also includes information regarding the PC5 QoS flow to be used for the UE to network relay connection. 
     The relay UE forwards the UE to network relay connection setup request (block  811 ). The UE to network relay connection setup request may be forwarded to a serving access node serving the relay UE, for example. The relay UE receives a UE to network relay connection setup response (block  813 ). The UE to network relay connection setup response may be received from the serving access node. The relay UE receives the RLC configuration over the PC5 interface between the remote UE and the relay UE. In the Layer-2 relay mode, the relay UE is also provided with the adaptation configuration to map RLC channels of the Uu interface (between the serving access node and the relay UE) and RLC channels of the PC5 interface (between the relay UE and the remote UE) for remote UE&#39;s packets of corresponding radio bearers, and a signaling containing radio bearer configurations of the remote UE, including SDAP and PDCP configurations (e.g., mappings of 5G QoS flows to DRBs, etc.). The relay UE sends the UE to network relay connection setup response (block  815 ). The relay UE sends the UE to network relay connection setup response to the remote UE, for example. 
     The relay UE receives the UE to network setup complete message (block  817 ). The UE to network setup complete message is received from the remote UE, for example. The relay UE receives signaling confirming the completion of the UE to network relay setup. The relay UE may also provide updates of the RLC configuration of the sidelink radio bearers. In the Layer-2 relay model, the relay UE receives a signaling containing confirmation of the proper configuration of SDAP and PDCP entities of the UE to network radio bearers. In the Layer-3 relay model, the relay UE receives the confirmation (along with possible updates) of the SDAP and PDCP configuration of sidelink DRBs. 
     The relay UE forwards the UE to network setup complete message (block  819 ). The relay UE informs the serving access node that sidelink RLC channels have been established for the UE to network relay, for example. In the Layer-2 relay model, the relay UE informs the serving access node that the mapping is established between the sidelink RLC channel and Uu RLC channel for packets of remote UE&#39;s respective radio bearers for the adaptation layer. The relay UE forwards the signaling containing confirmation of proper configuration of SDAP and PDCP entities of UE to network radio bearers. In the Layer-3 relay model, the relay UE informs the serving access node that SDAP and PDCP entities have been established for sidelink DRBs. 
       FIG.  9    illustrates a flow diagram of example operations  900  occurring in a serving access node participating in the establishment of a UE to network relay connection. Operations  900  may be indicative of operations occurring in a serving access node as the serving access node participates in the establishment of a UE to network relay connection. Layer-2 and Layer-3 relay model connections may be established. 
     Operations  900  begin with the serving access node performing relay UE discovery and authorization (block  905 ). Relay UE discovery and authorization is performed to detect relay UEs that are suitable candidates for operation as a relay UE for a remote UE. As an example, in order to be a suitable candidate for operation as a relay UE for the remote UE, a relay UE may need to be located within a specified distance to the remote UE (or a channel between the remote UE and the remote UE has adequate signal quality), as well as the relay UE being amenable to serving as a relay UE for the remote UE and the relay UE be authorized to serve as a relay UE for the remote UE. As part of the relay UE discovery and authorization, the remote UE is provided with information related to the serving access node (e.g., the PLMN and cell identities of the serving access node). 
     The serving access node receives the UE to network relay connection setup request (block  907 ). The UE to network relay connection setup request is a request for the establishment of the UE to network relay connection. The request includes information that includes a PLMN selected by the remote UE, as well as the identity of the remote UE. In the case of the Layer-3 relay model, the request also includes information regarding the PC5 QoS flow to be used for the UE to network relay connection. 
     The serving access node performs admission control (block  909 ). Based on the information of the remote UE and the relay UE, the serving access node and the network control function (e.g., AMF, SMF, or PCF) perform a policy check and admission control to allow the indirect 5G connection of the remote UE through the relay UE. In the case of the Layer-2 relay model, the serving access node is provided with the QoS flow information of the remote UE. 
     The serving access node sends the UE to network relay connection setup response (block  911 ). The UE to network relay connection setup response may indicate to the remote UE that the UE to network relay connection setup is approved. The response may be received from the relay UE, where the relay UE has configured RLC entities of the sidelink radio bearers. In the case of the Layer-2 relay model, the remote UE also receives a signaling containing bearer configurations, which includes SDAP and PDCP configurations, such as the mappings of 5G QoS flows to DRBs. In the case of the Layer-3 relay model, the remote UE is configured with SDAP and PDCP configurations of the sidelink DRBs over the PC5 interface between the remote UE and the relay UE. The configurations may include the PC5 QoS flow to DRB mappings. 
     The serving access node receives the UE to network relay connection setup complete message (block  913 ). The UE to network relay connection setup complete message includes confirmation of the completion of configurations of the UE to network relay connection setup, e.g., configurations of RLC channels over Uu interface and sidelink interface. The serving access node may also receive updates of the RLC configuration of the sidelink radio bearers. The serving access node also receives from the relay UE a signaling containing confirmation of the proper configuration of SDAP and PDCP entities of the remote UE for UE to network relay connection. 
       FIG.  10    illustrates a flow diagram of example operations  100  occurring in a network control function participating in the establishment of a UE to network relay connection. Operations  100  may be indicative of operations occurring in a network function as the network function participates in the establishment of a UE to network relay connection. Layer-2 and Layer-3 relay model connections may be established. Examples of the network control function includes the AMF, SMF, or PCF. 
     Operations  100  begin with the network control function performing relay UE discovery and authorization (block  1005 ). Relay UE discovery and authorization is performed to detect relay UEs that are suitable candidates for operation as a relay UE for a remote UE. As an example, in order to be a suitable candidate for operation as a relay UE for the remote UE, a relay UE may need to be located within a specified distance to the remote UE (or a channel between the remote UE and the remote UE has adequate signal quality), as well as the relay UE being amenable to serving as a relay UE for the remote UE and the relay UE be authorized to serve as a relay UE for the remote UE. As part of the relay UE discovery and authorization, the remote UE is provided with information related to the serving access node (e.g., the PLMN and cell identities of the serving access node). 
     The network control function performs admission control (block  1007 ). Based on the information of the remote UE and the relay UE, the network control function and the serving access node perform a policy check and admission control to allow the indirect 5G connection of the remote UE through the relay UE. In the case of the Layer-2 relay model, the network control function is provided with the QoS flow information of the remote UE. 
       FIG.  11    illustrates an example communication system  1100 . In general, the system  1100  enables multiple wireless or wired users to transmit and receive data and other content. The system  1100  may implement one or more channel access methods, such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), single-carrier FDMA (SC-FDMA), or non-orthogonal multiple access (NOMA). 
     In this example, the communication system  1100  includes electronic devices (ED)  1110   a - 1110   c , radio access networks (RANs)  1120   a - 1120   b , a core network  1130 , a public switched telephone network (PSTN)  1140 , the Internet  1150 , and other networks  1160 . While certain numbers of these components or elements are shown in  FIG.  11   , any number of these components or elements may be included in the system  1100 . 
     The EDs  1110   a - 1110   c  are configured to operate or communicate in the system  1100 . For example, the EDs  1110   a - 1110   c  are configured to transmit or receive via wireless or wired communication channels. Each ED  1110   a - 1110   c  represents any suitable end user device and may include such devices (or may be referred to) as a user equipment or device (UE), wireless transmit or receive unit (WTRU), mobile station, fixed or mobile subscriber unit, cellular telephone, personal digital assistant (PDA), smartphone, laptop, computer, touchpad, wireless sensor, or consumer electronics device. 
     The RANs  1120   a - 1120   b  here include base stations  1170   a - 1170   b , respectively. Each base station  1170   a - 1170   b  is configured to wirelessly interface with one or more of the EDs  1110   a - 1110   c  to enable access to the core network  1130 , the PSTN  1140 , the Internet  1150 , or the other networks  1160 . For example, the base stations  1170   a - 1170   b  may include (or be) one or more of several well-known devices, such as a base transceiver station (BTS), a Node-B (NodeB), an evolved NodeB (eNodeB), a Next Generation (NG) NodeB (gNB), a Home NodeB, a Home eNodeB, a site controller, an access point (AP), or a wireless router. The EDs  1110   a - 1110   c  are configured to interface and communicate with the Internet  115   o  and may access the core network  1130 , the PSTN  1140 , or the other networks  1160 . 
     In the embodiment shown in Figure ii, the base station  1170   a  forms part of the RAN  1120   a , which may include other base stations, elements, or devices. Also, the base station  1170   b  forms part of the RAN mob, which may include other base stations, elements, or devices. Each base station  1170   a - 1170   b  operates to transmit or receive wireless signals within a particular geographic region or area, sometimes referred to as a “cell.” In some embodiments, multiple-input multiple-output (MIMO) technology may be employed having multiple transceivers for each cell. 
     The base stations  1170   a - 1170   b  communicate with one or more of the EDs  1110   a - 1110   c  over one or more air interfaces  1190  using wireless communication links. The air interfaces  1190  may utilize any suitable radio access technology. 
     It is contemplated that the system  1100  may use multiple channel access functionality, including such schemes as described above. In particular embodiments, the base stations and EDs implement 5G New Radio (NR), LTE, LTE-A, or LTE-B. Of course, other multiple access schemes and wireless protocols may be utilized. 
     The RANs  1120   a - 1120   b  are in communication with the core network  1130  to provide the EDs  1110   a - 1110   c  with voice, data, application, Voice over Internet Protocol (VoIP), or other services. Understandably, the RANs  1120   a - 1120   b  or the core network  1130  may be in direct or indirect communication with one or more other RANs (not shown). The core network  1130  may also serve as a gateway access for other networks (such as the PSTN  1140 , the Internet  1150 , and the other networks  1160 ). In addition, some or all of the EDs  1110   a - 1110   c  may include functionality for communicating with different wireless networks over different wireless links using different wireless technologies or protocols. Instead of wireless communication (or in addition thereto), the EDs may communicate via wired communication channels to a service provider or switch (not shown), and to the Internet  1150 . 
     Although  FIG.  11    illustrates one example of a communication system, various changes may be made to  FIG.  11   . For example, the communication system  1100  could include any number of EDs, base stations, networks, or other components in any suitable configuration. 
       FIGS.  12 A and  12 B  illustrate example devices that may implement the methods and teachings according to this disclosure. In particular,  FIG.  12 A  illustrates an example ED  1210 , and  FIG.  12 B  illustrates an example base station  1270 . These components could be used in the system  1100  or in any other suitable system. 
     As shown in  FIG.  12 A , the ED  1210  includes at least one processing unit  1200 . The processing unit  1200  implements various processing operations of the ED  1210 . For example, the processing unit  1200  could perform signal coding, data processing, power control, input/output processing, or any other functionality enabling the ED  1210  to operate in the system  1100 . The processing unit  1200  also supports the methods and teachings described in more detail above. Each processing unit  1200  includes any suitable processing or computing device configured to perform one or more operations. Each processing unit  1200  could, for example, include a microprocessor, microcontroller, digital signal processor, field programmable gate array, or application specific integrated circuit. 
     The ED  1210  also includes at least one transceiver  1202 . The transceiver  1202  is configured to modulate data or other content for transmission by at least one antenna or NIC (Network Interface Controller)  1204 . The transceiver  1202  is also configured to demodulate data or other content received by the at least one antenna  1204 . Each transceiver  1202  includes any suitable structure for generating signals for wireless or wired transmission or processing signals received wirelessly or by wire. Each antenna  1204  includes any suitable structure for transmitting or receiving wireless or wired signals. One or multiple transceivers  1202  could be used in the ED  1210 , and one or multiple antennas  1204  could be used in the ED  1210 . Although shown as a single functional unit, a transceiver  1202  could also be implemented using at least one transmitter and at least one separate receiver. 
     The ED  1210  further includes one or more input/output devices  1206  or interfaces (such as a wired interface to the Internet  1150 ). The input/output devices  1206  facilitate interaction with a user or other devices (network communications) in the network. Each input/output device  1206  includes any suitable structure for providing information to or receiving information from a user, such as a speaker, microphone, keypad, keyboard, display, or touch screen, including network interface communications. 
     In addition, the ED  1210  includes at least one memory  1208 . The memory  1208  stores instructions and data used, generated, or collected by the ED  1210 . For example, the memory  1208  could store software or firmware instructions executed by the processing unit(s)  1200  and data used to reduce or eliminate interference in incoming signals. Each memory  1208  includes any suitable volatile or non-volatile storage and retrieval device(s). Any suitable type of memory may be used, such as random access memory (RAM), read only memory (ROM), hard disk, optical disc, subscriber identity module (SIM) card, memory stick, secure digital (SD) memory card, and the like. 
     As shown in  FIG.  12 B , the base station  1270  includes at least one processing unit  1250 , at least one transceiver  1252 , which includes functionality for a transmitter and a receiver, one or more antennas  1256 , at least one memory  1258 , and one or more input/output devices or interfaces  1266 . A scheduler, which would be understood by one skilled in the art, is coupled to the processing unit  1250 . The scheduler could be included within or operated separately from the base station  1270 . The processing unit  1250  implements various processing operations of the base station  1270 , such as signal coding, data processing, power control, input/output processing, or any other functionality. The processing unit  1250  can also support the methods and teachings described in more detail above. Each processing unit  1250  includes any suitable processing or computing device configured to perform one or more operations. Each processing unit  1250  could, for example, include a microprocessor, microcontroller, digital signal processor, field programmable gate array, or application specific integrated circuit. 
     Each transceiver  1252  includes any suitable structure for generating signals for wireless or wired transmission to one or more EDs or other devices. Each transceiver  1252  further includes any suitable structure for processing signals received wirelessly or by wire from one or more EDs or other devices. Although shown combined as a transceiver  1252 , a transmitter and a receiver could be separate components. Each antenna  1256  includes any suitable structure for transmitting or receiving wireless or wired signals. While a common antenna  1256  is shown here as being coupled to the transceiver  1252 , one or more antennas  1256  could be coupled to the transceiver(s)  1252 , allowing separate antennas  1256  to be coupled to the transmitter and the receiver if equipped as separate components. Each memory  1258  includes any suitable volatile or non-volatile storage and retrieval device(s). Each input/output device  1266  facilitates interaction with a user or other devices (network communications) in the network. Each input/output device  1266  includes any suitable structure for providing information to or receiving/providing information from a user, including network interface communications. 
       FIG.  13    is a block diagram of a computing system  1300  that may be used for implementing the devices and methods disclosed herein. For example, the computing system can be any entity of UE, access network (AN), mobility management (MM), session management (SM), user plane gateway (UPGW), or access stratum (AS). Specific devices may utilize all of the components shown or only a subset of the components, and levels of integration may vary from device to device. Furthermore, a device may contain multiple instances of a component, such as multiple processing units, processors, memories, transmitters, receivers, etc. The computing system  1300  includes a processing unit  1302 . The processing unit includes a central processing unit (CPU)  1314 , memory  1308 , and may further include a mass storage device  1304 , a video adapter  1310 , and an I/O interface  1312  connected to a bus  1320 . 
     The bus  1320  may be one or more of any type of several bus architectures including a memory bus or memory controller, a peripheral bus, or a video bus. The CPU  1314  may comprise any type of electronic data processor. The memory  1308  may comprise any type of non-transitory system memory such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous DRAM (SDRAM), read-only memory (ROM), or a combination thereof. In an embodiment, the memory  1308  may include ROM for use at boot-up, and DRAM for program and data storage for use while executing programs. 
     The mass storage  1304  may comprise any type of non-transitory storage device configured to store data, programs, and other information and to make the data, programs, and other information accessible via the bus  1320 . The mass storage  1304  may comprise, for example, one or more of a solid state drive, hard disk drive, a magnetic disk drive, or an optical disk drive. 
     The video adapter  1310  and the I/O interface  1312  provide interfaces to couple external input and output devices to the processing unit  1302 . As illustrated, examples of input and output devices include a display  1318  coupled to the video adapter  1310  and a mouse, keyboard, or printer  1316  coupled to the I/O interface  1312 . Other devices may be coupled to the processing unit  1302 , and additional or fewer interface cards may be utilized. For example, a serial interface such as Universal Serial Bus (USB) (not shown) may be used to provide an interface for an external device. 
     The processing unit  1302  also includes one or more network interfaces  1306 , which may comprise wired links, such as an Ethernet cable, or wireless links to access nodes or different networks. The network interfaces  1306  allow the processing unit  1302  to communicate with remote units via the networks. For example, the network interfaces  1306  may provide wireless communication via one or more transmitters/transmit antennas and one or more receivers/receive antennas. In an embodiment, the processing unit  1302  is coupled to a local-area network  1322  or a wide-area network for data processing and communications with remote devices, such as other processing units, the Internet, or remote storage facilities. 
       FIG.  14    illustrates a block diagram of an embodiment processing system  1400  for performing methods described herein, which may be installed in a host device. As shown, the processing system  1400  includes a processor  1404 , a memory  1406 , and interfaces  1410 - 1414 , which may (or may not) be arranged as shown in  FIG.  14   . The processor  1404  may be any component or collection of components adapted to perform computations and/or other processing related tasks, and the memory  1406  may be any component or collection of components adapted to store programming and/or instructions for execution by the processor  1404 . In an embodiment, the memory  1406  includes a non-transitory computer readable medium. The interfaces  1410 ,  1412 ,  1414  may be any component or collection of components that allow the processing system  1400  to communicate with other devices/components and/or a user. For example, one or more of the interfaces  1410 ,  1412 ,  1414  may be adapted to communicate data, control, or management messages from the processor  1404  to applications installed on the host device and/or a remote device. As another example, one or more of the interfaces  1410 ,  1412 ,  1414  may be adapted to allow a user or user device (e.g., personal computer (PC), etc.) to interact/communicate with the processing system  1400 . The processing system  1400  may include additional components not depicted in  FIG.  14   , such as long term storage (e.g., non-volatile memory, etc.). 
     In some embodiments, the processing system  1400  is included in a network device that is accessing, or part otherwise of, a telecommunications network. In one example, the processing system  1400  is in a network-side device in a wireless or wireline telecommunications network, such as a base station, a relay station, a scheduler, a controller, a gateway, a router, an applications server, or any other device in the telecommunications network. In other embodiments, the processing system  1400  is in a user-side device accessing a wireless or wireline telecommunications network, such as a mobile station, a user equipment (UE), a personal computer (PC), a tablet, a wearable communications device (e.g., a smartwatch, etc.), or any other device adapted to access a telecommunications network. 
     In some embodiments, one or more of the interfaces  1410 ,  1412 ,  1414  connects the processing system  1400  to a transceiver adapted to transmit and receive signaling over the telecommunications network.  FIG.  15    illustrates a block diagram of a transceiver  1500  adapted to transmit and receive signaling over a telecommunications network. The transceiver  1500  may be installed in a host device. As shown, the transceiver  1500  comprises a network-side interface  1502 , a coupler  1504 , a transmitter  1506 , a receiver  1508 , a signal processor  1510 , and a device-side interface  1512 . The network-side interface  1502  may include any component or collection of components adapted to transmit or receive signaling over a wireless or wireline telecommunications network. The coupler  1504  may include any component or collection of components adapted to facilitate bi-directional communication over the network-side interface  1502 . The transmitter  1506  may include any component or collection of components (e.g., up-converter, power amplifier, etc.) adapted to convert a baseband signal into a modulated carrier signal suitable for transmission over the network-side interface  1502 . The receiver  1508  may include any component or collection of components (e.g., down-converter, low noise amplifier, etc.) adapted to convert a carrier signal received over the network-side interface  1502  into a baseband signal. The signal processor  1510  may include any component or collection of components adapted to convert a baseband signal into a data signal suitable for communication over the device-side interface(s)  1512 , or vice-versa. The device-side interface(s)  1512  may include any component or collection of components adapted to communicate data-signals between the signal processor  1510  and components within the host device (e.g., the processing system  1400 , local area network (LAN) ports, etc.). 
     The transceiver  1500  may transmit and receive signaling over any type of communications medium. In some embodiments, the transceiver  1500  transmits and receives signaling over a wireless medium. For example, the transceiver  1500  may be a wireless transceiver adapted to communicate in accordance with a wireless telecommunications protocol, such as a cellular protocol (e.g., long-term evolution (LTE), etc.), a wireless local area network (WLAN) protocol (e.g., Wi-Fi, etc.), or any other type of wireless protocol (e.g., Bluetooth, near field communication (NFC), etc.). In such embodiments, the network-side interface  1502  comprises one or more antenna/radiating elements. For example, the network-side interface  1502  may include a single antenna, multiple separate antennas, or a multi-antenna array configured for multi-layer communication, e.g., single input multiple output (SIMO), multiple input single output (MISO), multiple input multiple output (MIMO), etc. In other embodiments, the transceiver  1500  transmits and receives signaling over a wireline medium, e.g., twisted-pair cable, coaxial cable, optical fiber, etc. Specific processing systems and/or transceivers may utilize all of the components shown, or only a subset of the components, and levels of integration may vary from device to device. 
     It should be appreciated that one or more steps of the embodiment methods provided herein may be performed by corresponding circuits, units, or modules. For example, a signal may be transmitted by a transmitting circuit, unit, or module. A signal may be received by a receiving circuit, unit, or module. A signal may be processed by a processing circuit, unit, or module. Other steps may be performed by a participating circuit, unit, or module. The respective circuits, units, or modules may be hardware, software, or a combination thereof. For instance, one or more of the circuits, units, or modules may be an integrated circuit, such as field programmable gate arrays (FPGAs) or application-specific integrated circuits (ASICs). 
     Although the present disclosure and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the scope of the disclosure as defined by the appended claims.