PATENT DOCUMENT

Publication Number: US-12096498-B2
Application Number: US-202318119463-A
Country: US
Kind Code: B2

Title: Separation of control plane and user plane in new radio (NR) systems

Abstract:
Embodiments of a Next Generation Node B (gNB) are described herein. The gNB may be configured with logical nodes, including a gNB central unit (gNB-CU) and a gNB distributed unit (gNB-DU). The gNB-CU may include a gNB-CU control plane (gNB-CU-CP) for control-plane functionality, and a gNB-CU user plane (gNB-CU-UP) for user-plane functionality. The gNB may initiate an E1 interface setup procedure, a bearer context setup procedure, and a UE context setup procedure to establish a UE context that includes a signaling radio bearer (SRB) and a data radio bearer (DRB) configuration. The UE context setup request message may be configured to include quality-of-service parameters for the DRB configuration.

Claims:
What is claimed is: 
     
       1. An apparatus, comprising:
 at least one processor configured to implement a new radio node B central unit control plane (gNB-CU-CP) for control-plane functionality of a gNB-CU logical node, the gNB-CU-CP configured to communicate control plane messages with a new radio node B distributed unit (gNB-DU) over an F1 control plane interface (F1-C), wherein the at least one processor is configured to:
 transmit or receive first messages, the first messages including:
 a UE context setup request message to the gNB-DU over the F1-C, wherein the UE context setup message is configured to include first quality-of-service parameters; 
 a UE context modify message to the gNB-DU over the F1-C, wherein the UE context modify message is configured to include second quality-of-service parameters; 
 a UE context release message to the gNB-DU over the F1-C; and 
 an uplink radio-resource control (RRC) message transfer message from the gNB-DU over the F1-C. 
 
 
 
     
     
       2. The apparatus of  claim 1 , wherein the UE context setup request message further includes one or more of: an aggregate maximum bit rate (AMBR), a latency, a bit error rate, and a packet error rate. 
     
     
       3. The apparatus of  claim 1 , wherein the UE context modify message includes an updated value of one of the parameters of the UE context setup request message. 
     
     
       4. The apparatus of  claim 1 , wherein the UE context release message indicates that a data radio bearer (DRB) is to be released. 
     
     
       5. The apparatus of  claim 1 , wherein the at least one processor is further configured to:
 receive, from the gNB-DU, a request from a UE for on-demand system information (SI) related to a capability of the UE to camp on a cell that includes a disaggregated gNB; and 
 send to the gNB-DU on the F1 interface, a downlink RRC message transfer that includes the on-demand SI. 
 
     
     
       6. The apparatus of  claim 1 , wherein the at least one processor is further configured to:
 receive, from the gNB-DU, an uplink RRC message transfer that includes one or more measurement reports or a response to an RRC connection request from the UE; and 
 send to the gNB-DU on the F1 interface, a downlink RRC message transfer to configure, reconfigure, or release an RRC connection at the UE. 
 
     
     
       7. The apparatus of  claim 1 , wherein the gNB-CU-CP is configured to communicate with a gNB-CU user plane (gNB-CU-UP) for user-plane functionality of the gNB-CU logical node over an E1 interface. 
     
     
       8. The apparatus of  claim 1 , wherein the apparatus is configured to transmit or receive all of the UE context setup request message, the UE context modify message, the UE context release message, and the uplink RRC message transfer message in a single session. 
     
     
       9. An apparatus, comprising:
 at least one processor configured to implement a new radio node B central unit user plane (gNB-CU-UP) for user-plane functionality of a gNB-CU logical node, the gNB-CU-UP configured to communicate with a gNB-CU control plane (gNB-CU-CP) for control-plane functionality of a gNB-CU logical node over an E1 interface, wherein the at least one processor is configured to:
 transmit or receive first messages according to an E1 application protocol (E1-AP), the first messages including:
 a GNB-CU-UP E1 setup request message from the gNB-CU-UP, wherein the E1 setup request message includes a gNB-CU-UP ID that is at least a local ID; 
 a radio bearer configuration message to the gNB-CU-UP over the E1 interface to configure one or more data radio bearers (DRBs), wherein the radio bearer configuration message includes a user equipment ID and a DRB ID; 
 a reset message over the E1 interface from the gNB-CU-UP or to the gNB-CU-UP; and 
 an error indication message over the E1 interface from the gNB-CU-UP indicating a cause of the error. 
 
 
 
     
     
       10. The apparatus of  claim 9 , wherein the gNB-CU-UP is configured to communicate control plane messages with a new radio node B distributed unit (gNB-DU) over an F1 control plane interface (F1-C). 
     
     
       11. The apparatus of  claim 9 , wherein a bearer context setup procedure is performed after completion of an E1 interface setup procedure. 
     
     
       12. The apparatus of  claim 9 , wherein the at least one processor is configured to transmit or receive the GNB-CU-UP E1 setup request message, the radio bearer configuration message, the reset message, and the error indication message in a single session. 
     
     
       13. An apparatus, comprising:
 at least one processor configured to implement a new radio node B distributed unit (gNB-DU), the gNB-DU configured to communicate control plane messages with a new radio node B central unit control plane (gNB-CU-CP) over an F1 control plane interface (F1-C), the new radio node B central unit control plane (gNB-CU-CP) for control-plane functionality of a gNB-CU logical node, wherein the at least one processor is configured to:
 transmit or receive first messages, the first messages including:
 a UE context setup request message to the gNB-DU over the F1-C, wherein the UE context setup message is configured to include first quality-of-service parameters; 
 a UE context modify message to the gNB-DU over the F1-C, wherein the UE context modify message is configured to include second quality-of-service parameters; 
 a UE context release message to the gNB-DU over the F1-C; and 
 an uplink radio-resource control (RRC) message transfer message from the gNB-DU over the F1-C. 
 
 
 
     
     
       14. The apparatus of  claim 13 , wherein the at least one processor is configured to transmit or receive the UE context setup request message, the UE context modify message, the context release message, and the uplink RRC message transfer message in a single session. 
     
     
       15. The apparatus of  claim 13 , wherein the gNB-CU-CP is configured to communicate with a gNB-CU user plan (gnB-CU-UP) for user plane functionality of the gNB CU logical node over and E1 interface. 
     
     
       16. The apparatus of  claim 13 , wherein the UE context setup request message further includes one or more of: an aggregate maximum bit rate (AMBR), a latency, a bit error rate, and a packet error rate. 
     
     
       17. The apparatus of  claim 13 , wherein the UE context modify message includes an updated value of one of the parameters of the UE context setup request message. 
     
     
       18. The apparatus of  claim 13 , wherein the UE context release message indicates that a data radio bearer (DRB) is to be released. 
     
     
       19. The apparatus of  claim 13 , wherein the at least one processor is further configured to:
 transmit, to the gNB-CU-CP, a request from a UE for on-demand system information (SI) related to a capability of the UE to camp on a cell that includes a disaggregated gNB; and 
 receive, from the gNB-CU-CP on the F1 interface, a downlink RRC message transfer that includes the on-demand SI. 
 
     
     
       20. The apparatus of  claim 13 , wherein the at least one processor is further configured to:
 transmit, to the gNB-CU-CP, an uplink RRC message transfer that includes one or more measurement reports or a response to an RRC connection request from the UE; and 
 receive, from the gNB-CU-CP on the F1 interface, a downlink RRC message transfer to configure, reconfigure, or release an RRC connection at the UE. 
 
     
     
       21. The apparatus of  claim 13 , wherein the second quality-of-service parameters are modified quality-of-service parameters, different from the first quality-of-service parameters. 
     
     
       22. The apparatus of  claim 13 , wherein the first quality-of-service parameters are the same as the second quality-of-service parameters. 
     
     
       23. The apparatus of  claim 1 , wherein the second quality-of-service parameters are modified quality-of-service parameters, different from the first quality-of-service parameters. 
     
     
       24. The apparatus of  claim 1 , wherein the first quality-of-service parameters are the same as the second quality-of-service parameters. 
     
     
       25. A method, comprising:
 implementing a new radio node B central unit control plane (gNB-CU-CP) for control-plane functionality of a gNB-CU logical node, the gNB-CU-CP configured to communicate control plane messages with a new radio node B distributed unit (gNB-DU) over an F1 control plane interface (F1-C), wherein said implementing the gNB-CU-CP comprises:
 transmitting a UE context setup request message to the gNB-DU over the F1-C, wherein the UE context setup message is configured to include first quality-of-service parameters; 
 transmitting a UE context modify message to the gNB-DU over the F1-C, wherein the UE context modify message is configured to include second quality-of-service parameters; 
 transmitting a UE context release message to the gNB-DU over the F1-C; and 
 receiving an uplink radio-resource control (RRC) message transfer message from the gNB-DU over the F1-C. 
 
 
     
     
       26. The method of  claim 25 , wherein the second quality-of-service parameters are modified quality-of-service parameters, different from the first quality-of-service parameters. 
     
     
       27. The method of  claim 25 , wherein the first quality-of-service parameters are the same as the second quality-of-service parameters. 
     
     
       28. A method, comprising:
 implementing a new radio node B distributed unit (gNB-DU), the gNB-DU configured to communicate control plane messages with a new radio node B central unit control plane (gNB-CU-CP) over an F1 control plane interface (F1-C), the new radio node B central unit control plane (gNB-CU-CP) for control-plane functionality of a gNB-CU logical node, wherein said implementing the gNB-DU comprises:
 receiving a UE context setup request message from the gNB-CU-CP over the F1-C, wherein the UE context setup message is configured to include first quality-of-service parameters; 
 receiving a UE context modify message from the gNB-CU-CP over the F1-C, wherein the UE context modify message is configured to include second quality-of-service parameters; 
 receiving a UE context release message from the gNB-CU-CP over the F1-C; and 
 transmitting an uplink radio-resource control (RRC) message transfer message to the gNB-CU-CP over the F1-C. 
 
 
     
     
       29. The method of  claim 28 , wherein the second quality-of-service parameters are modified quality-of-service parameters, different from the first quality-of-service parameters. 
     
     
       30. The method of  claim 28 , wherein the first quality-of-service parameters are the same as the second quality-of-service parameters.

Description:
PRIORITY CLAIM 
     This application is a continuation of U.S. application Ser. No. 17/517,182, filed Nov. 2, 2021, which is a continuation of U.S. application Ser. No. 16/615,081, filed Nov. 19, 2019 (now U.S. Pat. No. 11,197,332), which is a U.S. National Stage Filing under 35 U.S.C. 371 from International Application No. PCT/US2018/038284, filed Jun. 19, 2018 and published in English as WO 2018/236867 on Dec. 27, 2018, which claims priority to U.S. Provisional Patent Application Ser. No. 62/521,958, filed Jun. 19, 2017, each of which is incorporated herein by reference in its entirety. 
     The claims in the instant application are different than those of the parent application and/or other related applications. The Applicant therefore rescinds any disclaimer of claim scope made in the parent application and/or any predecessor application in relation to the instant application. Any such previous disclaimer and the cited references that it was made to avoid, may need to be revisited. Further, any disclaimer made in the instant application should not be read into or against the parent application and/or other related applications. 
    
    
     TECHNICAL FIELD 
     Embodiments pertain to \wireless communications. Some 15 embodiments relate to \wireless networks including 3GPP (Third Generation Partnership Project) networks, 3GPP LTE (Long Term Evolution) networks, and 3GPP LTE-A (LTE Advanced) networks. Some embodiments relate to Fifth Generation (5G) networks. Some embodiments relate to New Radio (NR) networks. Some embodiments relate to control plane functionality and/or user plane functionality. Some embodiments relate to splitting of control plane functionality and user plane functionality. 
     BACKGROUND 
     Base stations and mobile devices operating in a cellular network may exchange data. Functionality related to various protocol layers may be implemented in a base station to support communication; with mobile devices. In an example scenario, a large number of mobile devices may communicate with the base station. In another example scenario, performance targets for a mobile device, such as latency, delay and/or other, may be challenging for the base station to meet. Accordingly, there is a general need for methods and systems to implement communication between the base station and the mobile devices in these and other scenarios. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1 A  is a functional diagram of an example network in accordance with some embodiments; 
         FIG.  1 B  is a functional diagram of another example network in accordance with some embodiments; 
         FIG.  2    illustrates a block diagram of an example machine in accordance with some embodiments; 
         FIG.  3    illustrates a user device in accordance with some aspects; 
         FIG.  4    illustrates a base station in accordance with some aspects; 
         FIG.  5    illustrates an exemplary communication circuitry according to some aspects; 
         FIG.  6    illustrates the operation of a method of communication in accordance with some embodiments; 
         FIG.  7    illustrates the operation of another method of communication in accordance with some embodiments; 
         FIG.  8    illustrates the operation of another method of communication in accordance with some embodiments; 
         FIG.  9    illustrates examples of protocol layers and functional splits in accordance with some embodiments; 
         FIG.  10    illustrates an example architecture in accordance with some embodiments; 
         FIG.  11 A  and  FIG.  11 B  illustrate example operations and example messages that may be exchanged in accordance with some embodiments; 
         FIG.  12    illustrates additional example operations and additional example messages that may be exchanged in accordance with some embodiments; and 
         FIG.  13    illustrates additional example operations and additional example messages that may be exchanged in accordance with some embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     The following description and the drawings sufficiently illustrate specific embodiments to enable those skilled in the art to practice them. Other embodiments may incorporate structural, logical, electrical, process, and other changes. Portions and features of some embodiments may be included in, or substituted for, those of other embodiments. Embodiments set forth in the claims encompass all available equivalents of those claims. 
       FIG.  1 A  is a functional diagram of an example network in accordance with some embodiments.  FIG.  1 B  is a functional diagram of another example network in accordance with some embodiments. In references herein, “ FIG.  1   ” may include  FIG.  1 A  and  FIG.  1 B . In some embodiments, the network  100  may be a Third Generation Partnership Project (3GPP) network. In some embodiments, the network  150  may be a 3GPP network. In a non-limiting example, the network  150  may be a new radio (NR) network. It should be noted that embodiments are not limited to usage of 3GPP networks, however, as other networks may be used in some embodiments. As an example, a Fifth Generation (5G) network may be used in some cases. As another example, a New Radio (NR) network may be used in some cases. As another example, a wireless local area network (WLAN) may be used in some cases. Embodiments are not limited to these example networks, however, as other networks may be used in some embodiments, in some embodiments, a network may include one or more components shown in  FIG.  1 A . Some embodiments may not necessarily include all components shown in  FIG.  1 A , and some embodiments may include additional components not shown in  FIG.  1 A . In some embodiments, a network may include one or more components shown in  FIG.  1 B . Some embodiments may not necessarily include all components shown in  FIG.  1 B , and some embodiments may include additional components not shown in  FIG.  1 B . In some embodiments, a network may include one or more components shown in  FIG.  1 A  and one or more components shown in  FIG.  1 B . In some embodiments, a network may include one or more components shown in  FIG.  1 A , one or more components shown in  FIG.  1 B  and one or more additional components. 
     The network  100  may comprise a radio access network (RAN)  101  and the core network  120  (e.g., shown as an evolved packet core (EPC)) coupled together through an S1 interface  115 . For convenience and brevity sake, only a portion of the core network  120 , as well as the RAN  101 , is shown. In a non-limiting example, the RAN  101  may be an evolved universal terrestrial radio access network (E-UTRAN). In another non-limiting example, the RAN  101  may include one or more components of a New Radio (NR) network. In another non-limiting example, the RAN  101  may include one or more components of an E-UTRAN and one or more components of another network (including but not limited to an NR network). 
     The core network  120  may include a mobility management entity (MME)  122 , a serving gateway (serving GW)  124 , and packet data network gateway (PDN GW)  126 . In some embodiments, the network  100  may include (and/or support) one or more Evolved Node-B&#39;s (eNBs)  104  (which may operate as base stations) for communicating with User Equipment (UE)  102 . The eNBs  104  may include macro eNBs and low power (LP) eNBs, in some embodiments. 
     In some embodiments, the network  100  may include (and/or support) one or more Next Generation Node-B&#39;s (gNBs)  105 . In some embodiments, one or more eNBs  104  may be configured to operate as gNBs  105 . Embodiments are not limited to the number of eNBs  104  shown in  FIG.  1 A  or to the number of gNBs  105  shown in  FIG.  1 A . In some embodiments, the network  100  may not necessarily include eNBs  104 . Embodiments are also not limited to the connectivity of components shown in  FIG.  1 A . 
     It should be noted that references herein to an eNB  104  or to a gNB  105  are not limiting. In some embodiments, one or more operations, methods and/or techniques (such as those described herein) may be practiced by a base station component (and/or other component), including but not limited to a gNB  105 , an eNB  104 , a serving cell, a transmit receive point (TRP) and/or other. In some embodiments, the base station component may be configured to operate in accordance with a New Radio (NR) protocol and/or NR standard, although the scope of embodiments is not limited in this respect. In some embodiments, the base station component may be configured to operate in accordance with a Fifth Generation (5G) protocol and/or 5G standard, although the scope of embodiments is not limited in this respect. 
     In some embodiments, the gNB  105  may include multiple components. In a non-limiting example shown in  130 , the gNB  105  may comprise one or more of: a central unit control (CU-C) entity  106 , a central unit user (CU-U) entity  107 , a distributed unit (DU)  108  and/or other component(s). The CU-C entity  106  and the CU-U entity  107  may communicate over the E1 interface  109 , although the scope of embodiments is not limited in this respect. The CU-C entity  106  and the DU  108  may communicate over the F1-C interface  110 , although the scope of embodiments is not limited in this respect. The CU-U  107  entity and the DU  108  may communicate over the F1-U interface  111 , although the scope of embodiments is not limited in this respect. In some embodiments, an F1 interface may comprise the F1-U interface  110  and the F1-C interface  111 . 
     In some embodiments, the CU-C entity  106 , the CU-U entity  107 , and the DU  108  may be part of a disaggregated gNB  105 . One or more of the CU-C entity  106 , the CU-U entity  107 , and the DU  108  may be co-located, in some embodiments. One or more of the CU-C entity  106 , the CU-U entity  107 , and the DU  108  may not necessarily be co-located, in some embodiments. Other arrangements are possible, including arrangements in which two or more of the CU-U entity  107 , the CU-C entity  106  and the DU  108  are co-located. 
     The scope of embodiments is not limited to arrangements in which the CU-C entity  106 , the CU-U entity  107 , and the DU  108  are part of a disaggregated gNB  105 , however. In some embodiments, one or more of the techniques, operations and/or methods described herein may be practiced by a CU-C entity  106 , a CU-U  107  entity and/or a DU  108  that may not necessarily be included in a disaggregated gNB  105 . 
     References herein to communication between the gNB  105  and another component (such as the UE  102 , MME  122 , SGW  124  and/or other) are not limiting. In some embodiments, such communication may be performed between the component (such as the UE  102 , MME  122 , SGW  124  and/or other) and one of the CU-C entity  106 , CU-U entity  107 , DU  108 . 
     References herein to an operation, technique and/or method performed by the gNB  105  are not limiting. In some embodiments, such an operation, technique and/or method may be performed by one of the CU-C entity  106 , CU-U entity  107 , DU  108 . 
     In some embodiments, one or more of the UEs  102 , gNBs  105 , CU-C entity  106 , CU-U entity  107 , DU  108  and/or eNBs  104  may be configured to operate in accordance with an NR protocol and/or NR techniques. References to a UE  102 , eNB  104 . CU-C entity  106 , CU-U entity  107 , DU  108  and/or gNB  105  as part of descriptions herein are not limiting. For instance, descriptions of one or more operations, techniques and/or methods practiced by a gNB  105  are not limiting. In some embodiments, one or more of those operations, techniques and/or methods may be practiced by an eNB  104  and/or other base station component. 
     In some embodiments, the UE  102  may transmit signals (data, control and/or other) to the gNB  105 , and may receive signals (data, control and/or other) from the gNB  105 . In some embodiments, the UE  102  may transmit signals (data, control and/or other) to the eNB  104 , and may receive signals (data, control and/or other) from the eNB  104 . These embodiments will be described in more detail below. In some embodiments, the UE  102  may transmit signals to a component of a disaggregated gNB  105  (such as the DU  108 ). In some embodiments, the UE  102  may receive signals from a component of a disaggregated gNB  105  (such as the DU  108 ). 
     The MME  122  is similar in function to the control plane of legacy Serving GPRS Support Nodes (SGSN). The MME  122  manages mobility aspects in access such as gateway selection and tracking area list management. The serving GW  124  terminates the interface toward the RAN  101 , and routes data packets between the RAN  101  and the core network  120 . In addition, it may be a local mobility anchor point for inter-eNB handovers and also may provide an anchor for inter-3GPP mobility. Other responsibilities may include lawful intercept, charging, and some policy enforcement. The serving GW  124  and the MME  122  may be implemented in one physical node or separate physical nodes. The PDN GW  126  terminates an SGi interface toward the packet data network (PDN). The PDN GW  126  routes data packets between the EPC  120  and the external PDN, and may be a key node for policy enforcement and charging data collection. It may also provide an anchor point for mobility with non-LTE accesses. The external PDN can be any kind of IP network, as well as an IP Multimedia Subsystem (IMS) domain. The PDN GW  126  and the serving GW  124  may be implemented in one physical node or separated physical nodes. 
     In some embodiments, the eNBs  104  (macro and micro) terminate the air interface protocol and may be the first point of contact for a UE  102 . In some embodiments, an eNB  104  may fulfill various logical functions for the network  100 , including but not limited to RNC (radio network controller functions) such as radio bearer management, uplink and downlink dynamic radio resource management and data packet scheduling, and mobility management. 
     In some embodiments, UEs  102  may be configured to communicate Orthogonal Frequency Division Multiplexing (OFDM) communication signals with an eNB  104  and/or gNB  105  over a multicarrier communication channel in accordance with an Orthogonal Frequency Division Multiple Access (OFDMA) communication technique. In some embodiments, eNBs  104  and/or gNBs  105  may be configured to communicate OFDM communication signals with a UE  102  over a multi carrier communication channel in accordance with an OFDMA communication technique. The OFDM  20  signals may comprise a plurality of orthogonal subcarriers. 
     The S1 interface  115  is the interface that separates the RAN  101  and the EPC  120 . It may be split into two parts: the S1-U, which carries traffic data between the eNBs  104  and the serving GW  124 , and the S1-MME, which is a signaling interface between the eNBs  104  and the MME  122 . The X2 interface is the interface between eNBs  104 . The X2 interface comprises two parts, the X2-C and X2-U. The X2-C is the control plane interface between the eNBs  104 , while the X2-U is the user plane interface between the eNBs  104 . 
     In some embodiments, similar functionality and/or connectivity described for the eNB  104  may be used for the gNB  105 , although the scope of embodiments is not limited in this respect. In a non-limiting example, the S1 interface  115  (and/or similar interface) may be split into two parts: the S1-U, which carries traffic data between the gNBs  105  and the serving GW  124 , and the S1-MME, which is a signaling interface between the gNBs  105  and the MME  122 . The X2 interface (and/or similar interface) may enable communication between eNBs  104 , communication between gNBs  105  and/or communication between an eNB  104  and a gNB  105 . 
     With cellular networks, LP cells are typically used to extend coverage to indoor areas where outdoor signals do not reach well, or to add network capacity in areas with very dense phone usage, such as train stations. As used herein, the term low power (LP) eNB refers to any suitable relatively low power eNB for implementing a narrower cell (narrower than a macro cell) such as a femtocell, a picocell, or a micro cell. Femtocell eNBs are typically provided by a mobile network operator to its residential or enterprise customers. A femtocell is typically the size of a residential gateway or smaller and generally connects to the user&#39;s broadband line. Once plugged in, the femtocell connects to the mobile operator&#39;s mobile network and provides extra coverage in a range of typically 30 to 50 meters for residential femtocells. Thus, a LP eNB might be a femtocell eNB since it is coupled through the PDN GW  126 . Similarly, a picocell is a wireless communication system typically covering a small area, such as in-building (offices, shopping malls, train stations, etc.), or more recently in-aircraft. A picocell eNB can generally connect through the X2 link to another eNB such as a macro eNB through its base station controller (BSC) functionality. Thus, LP eNB may be implemented with a picocell eNB since it is coupled to a macro eNB via an X2 interface. Picocell eNBs or other LP eNBs may incorporate some or all functionality of a macro eNB. In some cases, this may be referred to as an access point base station or enterprise femtocell. In some embodiments, various types of gNBs  105  may be used, including but not limited to one or more of the eNB types described above. 
     In some embodiments, the network  150  may include one or more components configured to operate in accordance with one or more 3GPP standards, including but not limited to an NR standard. The network  150  shown in  FIG.  1 B  may include a next generation RAN (NG-RAN)  155 , which may include one or more gNBs  105 . In some embodiments, the network  150  may include the E-UTRAN  16   tt  which may include one or more eNBs. The E-UTRAN  160  may be similar to the RAN  101  described herein, although the scope of embodiments is not limited in this respect. 
     In some embodiments, the network  150  may include the MME  165 . The MME  165  may be similar to the MME  122  described herein, although the scope of embodiments is not limited in this respect. The MME  165  may perform one or more operations or functionality similar to those described herein regarding the MME  122 , although the scope of embodiments is not limited in this respect. 
     In some embodiments, the network  150  may include the SGW  170 . The SGW  170  may be similar to the SGW  124  described herein, although the scope of embodiments is not limited in this respect. The SGW  170  may perform one or more operations or functionality similar to those described herein regarding the SGW  124 , although the scope of embodiments is not limited in this respect. 
     In some embodiments, the network  150  may include component(s) and/or module(s) for functionality for a user plane function (UPF) and user plane functionality for PGW (PGW-U), as indicated by  175 . In some embodiments, the network  150  may include component(s) and/or module(s) for functionality for a session management function (SMF) and control plane functionality for PGW (PGW-C), as indicated by  180 . In some embodiments, the component(s) and/or module(s) indicated by  175  and/or  180  may be similar to the PGW  126  described herein, although the scope of embodiments is not limited in this respect. The component(s) and/or module(s) indicated by  175  and/or  180  may perform one or more operations or functionality similar to those described herein regarding the PGW  126 , although the scope of embodiments is not limited in this respect. One or both of the components  170 ,  172  may perform at least a portion of the functionality described herein for the PGW  126 , although the scope of embodiments is not limited in this respect. 
     Embodiments are not limited to the number or type of components shown in  FIG.  1 B . Embodiments are also not limited to the connectivity of components shown in  FIG.  1 B . 
     In some embodiments, a downlink resource grid may be used for downlink transmissions from an eNB  104  to a UE  102 , while uplink transmission from the UE  102  to the eNB  104  may utilize similar techniques. In some embodiments, a downlink resource grid may be used for downlink transmissions from a gNB  105  to a UE  102 , while uplink transmission from the UE  102  to the gNB  105  may utilize similar techniques. The grid may be a time-frequency grid, called a resource grid or time-frequency resource grid, which is the physical resource in the downlink in each slot. Such a time-frequency plane representation is a common practice for OFDM systems, which makes it intuitive for radio resource allocation. Each column and each row of the resource grid correspond to one OFDM symbol and one OFDM subcarrier, respectively. The duration of the resource grid in the time domain corresponds to one slot in a radio frame. The smallest time-frequency unit in a resource grid is denoted as a resource element (RE). There are several different physical downlink channels that are conveyed using such resource blocks. With particular relevance to this disclosure, two of these physical downlink channels are the physical downlink shared channel and the physical down link control channel. 
     As used herein, the term “circuitry” may refer to, be part of, or include an Application Specific Integrated Circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or group), and/or memory (shared, dedicated, or group) that execute one or more software or firmware programs, a combinational logic circuit, and/or other suitable hardware components that provide the described functionality. In some embodiments, the circuitry may be implemented in, or functions associated with the circuitry may be implemented by, one or more software or firmware modules. In some embodiments, circuitry may include logic, at least partially operable in hardware. Embodiments described herein may be implemented into a system using any suitably configured hardware and/or software. 
       FIG.  2    illustrates a block diagram of an example machine in accordance with some embodiments. The machine  200  is an example machine upon which any one or more of the techniques and/or methodologies discussed herein may be performed. In alternative embodiments, the machine  200  may operate as a standalone device or may be connected (e.g., networked) to other machines. In a networked deployment, the machine  200  may operate in the capacity of a server machine, a client machine, or both in server-client network environments. In an example, the machine  200  may act as a peer machine in peer-to-peer (P2P) (or other distributed) network environment. The machine  200  may be a UE  102 , eNB  104 , gNB  105 , CU-C entity  106 , CU-U entity  107 , DU  108 , access point (AP), station (STA), user, device, mobile device, base station, personal computer (PC), a tablet PC, a set-top box (STB), a personal digital assistant (PDA), a mobile telephone, a smart phone, a web appliance, a network router, switch or bridge, or any machine capable of executing instructions (sequential or otherwise) that specify actions to be taken by that machine. Further, while only a single machine is illustrated, the term “machine” shall also be taken to include any collection of machines that individually or jointly execute a set (or multiple sets) of instructions to perform any one or more of the methodologies discussed herein, such as cloud computing, software as a service (SaaS), other computer cluster configurations. 
     Examples as described herein, may include, or may operate on, logic or a number of components, modules, or mechanisms. Modules are tangible entities (e.g., hardware) capable of performing specified operations and may be configured or arranged in a certain manner. In an example, circuits may be arranged (e.g., internally or with respect to external entities such as other circuits) in a specified manner as a module. In an example, the whole or part of one or more computer systems (e.g., a standalone, client or server computer system) or one or more hardware processors may be configured by firmware or software (e.g., instructions, an application portion, or an application) as a module that operates to perform specified operations. In an example, the software may reside on a machine readable medium. In an example, the software, when executed by the underlying hardware of the module, causes the hardware to perform the specified operations. 
     Accordingly, the term “module” is understood to encompass a tangible entity, be that an entity that is physically constructed, specifically configured (e.g., hardwired), or temporarily (e.g., transitorily) configured (e.g., programmed) to operate in a specified manner or to perform part or all of any operation described herein. Considering examples in which modules are temporarily configured, each of the modules need not be instantiated at any one moment in time. For example, where the modules comprise a general-purpose hardware processor configured using software, the general-purpose hardware processor may be configured as respective different modules at different times. Software may accordingly configure a hardware processor, for example, to constitute a particular module at one instance of time and to constitute a different module at a different instance of time. 
     The machine (e.g., computer system)  200  may include a hardware processor  202  (e.g., a central processing unit (CPU), a graphics processing unit (GPU), a hardware processor core, or any combination thereof), a main memory  204  and a static memory  206 , some or all of which may communicate with each other via an interlink (e.g., bus)  208 . The machine  200  may further include a display unit  210 , an alphanumeric input device  212  (e.g., a keyboard), and a user interface (UI) navigation device  214  (e.g., a mouse). In an example, the display unit  210 , input device  212  and UI navigation device  214  may be a touch screen display. The machine  200  may additionally include a storage device (e.g., drive unit)  216 , a signal generation device  218  (e.g., a speaker), a network interface device  220 , and one or more sensors  221 , such as a global positioning system (GPS) sensor, compass, accelerometer, or other sensor. The machine  200  may include an output controller  228 , such as a serial (e.g., universal serial bus (USB), parallel, or other wired or wireless (e.g., infrared (IR), near field communication (NFC), etc.) connection to communicate or control one or more peripheral devices (e.g., a printer, card reader, etc.). 
     The storage device  216  may include a machine readable medium  222  on which is stored one or more sets of data structures or instructions  224  (e.g., software) embodying or utilized by any one or more of the techniques or functions described herein. The instructions  224  may also reside, completely or at least partially, within the main memory  204 , within static memory  206 , or within the hardware processor  202  during execution thereof by the machine  200 . In an example, one or any combination of the hardware processor  202 , the main memory  204 , the static memory  206 , or the storage device  216  may constitute machine readable media. In some embodiments, the machine readable medium may be or may include a non-transitory computer-readable storage medium. In some embodiments, the machine readable medium may be or may include a computer-readable storage medium. 
     While the machine readable medium  222  is illustrated as a single medium, the term “machine readable medium” may include a single medium or multiple media (e.g., a centralized or distributed database, and/or associated caches and servers) configured to store the one or more instructions  224 . The term “machine readable medium” may include any medium that is capable of storing, encoding, or carrying instructions for execution by the machine  200  and that cause the machine  200  to perform any one or more of the techniques of the present disclosure, or that is capable of storing, encoding or carrying data structures used by or associated with such instructions. Non-limiting machine readable medium examples may include solid-state memories, and optical and magnetic media. Specific examples of machine readable media may include: non-volatile memory, such as semiconductor memory devices (e.g., Electrically Programmable Read-Only Memory (EPROM), Electrically Erasable Programmable Read-Only Memory (EEPROM)) and flash memory devices; magnetic disks, such as internal hard disks and removable disks; magneto-optical disks; Random Access Memory (RAM); and CD-ROM and DVD-ROM disks. In some examples, machine readable media may include non-transitory machine readable media. In some examples, machine readable media may include machine readable media that is not a transitory propagating signal. 
     The instructions  224  may further be transmitted or received over a communications network  226  using a transmission medium via the network interface device  220  utilizing any one of a number of transfer protocols (e.g., frame relay, internet protocol (IP), transmission control protocol (TCP), user datagram protocol (UDP), hypertext transfer protocol (HTTP), etc.). Example communication networks may include a local area network (LAN), a wide area network (WAN), a packet data network (e.g., the Internet), mobile telephone networks (e.g., cellular networks), Plain Old Telephone (POTS) networks, and wireless data networks (e.g., Institute of Electrical and Electronics Engineers (IEEE) 802.11 family of standards known as Wi-Fi®, IEEE 802.16 family of standards known as WiMax®), IEEE 802.15.4 family of standards, a Long Term Evolution (LTE) family of standards, a Universal Mobile Telecommunications System (UMTS) family of standards, peer-to-peer (P2P) networks, among others. In an example, the network interface device  220  may include one or more physical jacks (e.g., Ethernet, coaxial, or phone jacks) or one or more antennas to connect to the communications network  226 . In an example, the network interface device  220  may include a plurality of antennas to wirelessly communicate using at least one of single-input multiple-output (SIMO), multiple-input multiple-output (MIMO), or multiple-input single-output (MISO) techniques. In some examples, the network interface device  220  may wirelessly communicate using Multiple User MIMO techniques. The term “transmission medium” shall be taken to include any intangible medium that is capable of storing, encoding or carrying instructions for execution by the machine  200 , and includes digital or analog communications signals or other intangible medium to facilitate communication of such software. 
       FIG.  3    illustrates a user device in accordance with some aspects. In some embodiments, the user device  300  may be a mobile device. In some embodiments, the user device  300  may be or may be configured to operate as a User Equipment (UE). In some embodiments, the user device  300  may be arranged to operate in accordance with a new radio (NR) protocol. In some embodiments, the user device  300  may be arranged to operate in accordance with a Third Generation Partnership Protocol (3GPP) protocol. The user device  300  may be suitable for use as a UE  102  as depicted in  FIG.  1   , in some embodiments. It should be noted that in some embodiments, a UE, an apparatus of a UE, a user device or an apparatus of a user device may include one or more of the components shown in one or more of  FIGS.  2 ,  3 , and  5   . In some embodiments, such a UE, user device and/or apparatus may include one or more additional components. 
     In some aspects, the user device  300  may include an application processor  305 , baseband processor  310  (also referred to as a baseband module), radio front end module (RMEM)  315 , memory  320 , connectivity module  325 , near field communication (NFC) controller  330 , audio driver  335 , camera driver  340 , touch screen  345 , display driver  350 , sensors  355 , removable memory  360 , power management integrated circuit (PMIC)  365  and smart battery  370 . In some aspects, the user device  300  may be a User Equipment (UE). 
     In some aspects, application processor  305  may include, for example, one or more CPU cores and one or more of cache memory, low drop-out voltage regulators (LDOs), interrupt controllers, serial interfaces such as serial peripheral interface (SPI), inter-integrated circuit (I 2 C) or universal programmable serial interface module, real time clock (RTC), timer-counters including interval and watchdog timers, general purpose input-output (IO), memory card controllers such as secure digital/multi-media card (SD/MMC) or similar, universal serial bus (USB) interfaces, mobile industry processor interface (MIPI) interfaces and Joint Test Access Group (JTAG) test access ports. 
     In some aspects, baseband module  310  may be implemented, for example, as a solder-down substrate including one or more integrated circuits, a single packaged integrated circuit soldered to a main circuit board, and/or a multi-chip module containing two or more integrated circuits. 
       FIG.  4    illustrates a base station in accordance with some aspects. In some embodiments, the base station  400  may be or may be configured to operate as an Evolved Node-B (eNB). In some embodiments, the base station  400  may be or may be configured to operate as a Next Generation Node-B (gNB). In some embodiments, the base station  400  may be arranged to operate in accordance with a new radio (NR) protocol. In some embodiments, the base station  400  may be arranged to operate in accordance with a Third Generation Partnership Protocol (3GPP) protocol. It should be noted that in some embodiments, the base station  400  may be a stationary non-mobile device. The base station  400  may be suitable for use as an eNB  104  as depicted in  FIG.  1   , in some embodiments. The base station  400  may be suitable for use as a gNB  105  as depicted in  FIG.  1   , in some embodiments. It should be noted that in some embodiments, an eNB, an apparatus of an eNB, a gNB, an apparatus of a gNB, a CU-C entity  106 , a CU-U entity  107 , a DU  108 , an apparatus of a CU-C entity  106 , an apparatus of a CU-U entity  107 , an apparatus of a DU  108 , a base station and/or an apparatus of a base station may include one or more of the components shown in one or more of  FIGS.  2 ,  4 , and  5   . In some embodiments, such an eNB, gNB. CU-C entity  106 . CU-U entity  107 , DU  108 , base station and/or apparatus may include one or more additional components. 
       FIG.  4    illustrates a base station or infrastructure equipment radio head  400  in accordance with an aspect. The base station  400  may include one or more of application processor  405 , baseband modules  410 , one or more radio front end modules  415 , memory  420 , power management circuitry  425 , power tee circuitry  430 , network controller  435 , network interface connector  440 , satellite navigation receiver module  445 , and user interface  450 . In some aspects, the base station  400  may be an Evolved Node-B (eNB), which may be arranged to operate in accordance with a 3GPP protocol, new radio (NR) protocol and/or Fifth Generation (5G) protocol. In some aspects, the base station  400  may be a Next Generation Node-B (gNB), which may be arranged to operate in accordance with a 3GPP protocol, new radio (NR) protocol and/or Fifth Generation (5G) protocol. 
     In some aspects, application processor  405  may include one or more CPU cores and one or more of cache memory, low drop-out voltage regulators (LDOs), interrupt controllers, serial interfaces such as SPI, I 2 C or universal programmable serial interface module, real time clock (RTC), timer-counters including interval and watchdog timers, general purpose  10 , memory card controllers such as SD/MMC or similar, USB interfaces, MIPI interfaces and Joint Test Access Group (JTAG) test access ports. 
     In some aspects, baseband processor  410  may be implemented, for example, as a solder-down substrate including one or more integrated circuits, a single packaged integrated circuit soldered to a main circuit board or a multi-chip module containing two or more integrated circuits. 
     In some aspects, memory  420  may include one or more of volatile memory including dynamic random access memory (DRAM) and/or synchronous dynamic random access memory (SDRAM), and nonvolatile memory (NVM) including high-speed electrically erasable memory (commonly referred to as Flash memory), phase change random access memory (PRAM), magneto-resistive random access memory (MRAM) and/or a three-dimensional cross-point memory. Memory  420  may be implemented as one or more of solder down packaged integrated circuits, socketed memory modules and plug-in memory cards. 
     In some aspects, power management integrated circuitry  425  may include one or more of voltage regulators, surge protectors, power alarm detection circuitry and one or more backup power sources such as a battery or capacitor. Power alarm detection circuitry may detect one or more of brown out (under-voltage) and surge (over-voltage) conditions. 
     In some aspects, power tee circuitry  430  may provide for electrical power drawn from a network cable to provide both power supply and data connectivity to the base station  400  using a single cable. In some aspects, network controller  435  may provide connectivity to a network using a standard network interface protocol such as Ethernet. Network connectivity may be provided using a physical connection which is one of electrical (commonly referred to as copper interconnect), optical or wireless. 
     In some aspects, satellite navigation receiver module  445  may include circuitry to receive and decode signals transmitted by one or more navigation satellite constellations such as the global positioning system (GPS), Globalnaya Navigatsionnaya Sputnikovaya Sistema (GLONASS), Galileo and/or BeiDou. The receiver  445  may provide data to application processor  405  which may include one or more of position data or time data. Application processor  405  may use time data to synchronize operations with other radio base stations. In some aspects, user interface  450  may include one or more of physical or virtual buttons, such as a reset button, one or more indicators such as light emitting diodes (LEDs) and a display screen. 
       FIG.  5    illustrates an exemplary communication circuitry according to some aspects. Circuitry  500  is alternatively grouped according to functions. Components as shown in  5 X) are shown here for illustrative purposes and may include other components not shown here in  FIG.  5   . In some aspects, the communication circuitry  500  may be used for millimeter wave communication, although aspects are not limited to millimeter wave communication. Communication at any suitable frequency may be performed by the communication circuitry  500  in some aspects. 
     It should be noted that a device, such as a UE  102 , eNB  104 , gNB  105 , CU-C entity  106 , CU-U entity  107 , DU  108 , the user device  300 , the base station  400 , the machine  200  and/or other device may include one or more components of the communication circuitry  500 , in some aspects. 
     The communication circuitry  500  may include protocol processing circuitry  505 , which may implement one or more of medium access control (MAC), radio link control (RLC), packet data convergence protocol (PDCP), radio resource control (RRC) and non-access stratum (NAS) functions. Protocol processing circuitry  505  may include one or more processing cores (not shown) to execute instructions and one or more memory structures (not shown) to store program and data information. 
     The communication circuitry  500  may further include digital baseband circuitry  510 , which may implement physical layer (PHY) functions including one or more of hybrid automatic repeat request (HARQ) functions, scrambling and/or descrambling, coding and/or decoding, layer mapping and/or de-mapping, modulation symbol mapping, received symbol and/or bit metric determination, multi-antenna port pre-coding and/or decoding which may include one or more of space-time, space-frequency or spatial coding, reference signal generation and/or detection, preamble sequence generation and/or decoding, synchronization sequence generation and/or detection, control channel signal blind decoding, and other related functions. 
     The communication circuitry  500  may further include transmit circuitry  515 , receive circuitry  520  and/or antenna array circuitry  530 . The communication circuitry  500  may further include radio frequency (RF) circuitry  525 . In an aspect of the disclosure, RF circuitry  525  may include multiple parallel RF chains for one or more of transmit or receive functions, each connected to one or more antennas of the antenna array  530 . 
     In an aspect of the disclosure, protocol processing circuitry  505  may include one or more instances of control circuitry (not shown) to provide control functions for one or more of digital baseband circuitry  510 , transmit circuitry  515 , receive circuitry  520 , and/or radio frequency circuitry  525   
     In some embodiments, processing circuitry may perform one or more operations described herein and/or other operation(s). In a non-limiting example, the processing circuitry may include one or more components such as the processor  202 , application processor  305 , baseband module  310 , application processor  405 , baseband module  410 , protocol processing circuitry  505 , digital baseband circuitry  510 , similar component(s) and/or other component(s). 
     In some embodiments, a transceiver may transmit one or more elements (including but not limited to those described herein) and/or receive one or more elements (including but not limited to those described herein). In a non-limiting example, the transceiver may include one or more components such as the radio front end module  315 , radio front end module  415 , transmit circuitry  515 , receive circuitry  520 , radio frequency circuitry  525 , similar component(s) and/or other component(s). 
     One or more antennas (such as  230 ,  312 ,  412 ,  530  and/or others) may comprise one or more directional or omnidirectional antennas, including, for example, dipole antennas, monopole antennas, patch antennas, loop antennas, microstrip antennas or other types of antennas suitable for transmission of RF signals. In some multiple-input multiple-output (MIMO) embodiments, one or more of the antennas (such as  230 ,  312 ,  412 ,  530  and/or others) may be effectively separated to take advantage of spatial diversity and the different channel characteristics that may result. 
     In some embodiments, the UE  102 , eNB  104 , gNB  105 , CU-C entity  106 , CU-U entity  107 , DU  108 , user device  300 , base station  400 , machine  200  and/or other device described herein may be a mobile device and/or portable wireless communication device, such as a personal digital assistant (PDA), a laptop or portable computer with wireless communication capability, a web tablet, a wireless telephone, a smartphone, a wireless headset, a pager, an instant messaging device, a digital camera, an access point, a television, a wearable device such as a medical device (e.g., a heart rate monitor, a blood pressure monitor, etc.), or other device that may receive and/or transmit information wirelessly. In some embodiments, the UE  102 , eNB  104 , gNB  105 , CU-C entity  106 , CU-U entity  107 , DU  108 , user device  300 , base station  400 , machine  200  and/or other device described herein may be configured to operate in accordance with 3GPP standards, although the scope of the embodiments is not limited in this respect. In some embodiments, the UE  102 , eNB  104 , gNB  105 , CU-C entity  106 , CU-U entity  107 . DU  108 , user device  300 , base station  400 , machine  200  and/or other device described herein may be configured to operate in accordance with new radio (NR) standards, although the scope of the embodiments is not limited in this respect. In some embodiments, the UE  102 , eNB  104 , gNB  105 , CU-C entity  106 , CU-U entity  107 , DU  108 , user device  300 , base station  400 , machine  200  and/or other device described herein may be configured to operate according to other protocols or standards, including IEEE 802.11 or other IEEE standards. In some embodiments, the UE  102 , eNB  104 , gNB  105 , CU-C entity  106 , CU-U entity  107 , DU  108 , user device  300 , base station  400 , machine  200  and/or other device described herein may include one or more of a keyboard, a display, a non-volatile memory port, multiple antennas, a graphics processor, an application processor, speakers, and other mobile device elements. The display may be an LCD screen including a touch screen. 
     Although the UE  102 , eNB  104 , gNB  105 , CU-C entity  106 , CU-U entity  107 , DU  108 , user device  300 , base station  400 , machine  200  and/or other device described herein may each be illustrated as having several separate functional elements, one or more of the functional elements may be combined and may be implemented by combinations of software-configured elements, such as processing elements including digital signal processors (DSPs), and/or other hardware elements. For example, some elements may comprise one or more microprocessors, DSPs, field-programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), radio-frequency integrated circuits (RFICs) and combinations of various hardware and logic circuitry for performing at least the functions described herein. In some embodiments, the functional elements may refer to one or more processes operating on one or more processing elements. 
     Embodiments may be implemented in one or a combination of hardware, firmware and software. Embodiments may also be implemented as instructions stored on a computer-readable storage device, which may be read and executed by at least one processor to perform the operations described herein. A computer-readable storage device may include any non-transitory mechanism for storing information in a form readable by a machine (e.g., a computer). For example, a computer-readable storage device may include read-only memory (ROM), random-access memory (RAM), magnetic disk storage media, optical storage media, flash-memory devices, and other storage devices and media. Some embodiments may include one or more processors and may be configured with instructions stored on a computer-readable storage device. 
     It should be noted that in some embodiments, an apparatus of the UE  102 , eNB  104 , gNB  105 , CU-C entity  106 , CU-U entity  107 , DU  108 , machine  200 , user device  300  and/or base station  400  may include various components shown in  FIGS.  2 - 5   . Accordingly, techniques and operations described herein that refer to the UE  102  may be applicable to an apparatus of a UE. In addition, techniques and operations described herein that refer to the eNB  104  may be applicable to an apparatus of an eNB. In addition, techniques and operations described herein that refer to the gNB  105  may be applicable to an apparatus of a gNB. In addition, techniques and operations described herein that refer to the CU-C entity  106 , may be applicable to an apparatus of a CU-C entity. In addition, techniques and operations described herein that refer to the CU-U entity  107  may be applicable to an apparatus of a CU-U entity. In addition, techniques and operations described herein that refer to the DU  108  may be applicable to an apparatus of a DU. 
     It should be noted that some of the descriptions herein may refer to performance of operations, methods and/or techniques by elements such as the CU-C entity  106 , CU-U entity  107 , and the DU  108 . Such references are not limiting, however. One or more of the operations, methods and/or techniques may be performed by one or more other entities, in some embodiments. In a non-limiting example, an operation, method and/or technique described herein as performed by the CU-C entity  106  may be performed by a gNB-CU control plane (gNB-CU-CP) entity, in some embodiments. In another non-limiting example, an operation, method and/or technique described herein as performed by the CU-U entity  107  may be performed by a gNB-CU user plane (gNB-CU-UP) entity, in some embodiments. In another non-limiting example, an operation, method and/or technique described herein as performed by the DU  108  may be performed by a gNB distributed unit (gNB-DU) entity, in some embodiments. 
     In accordance with some embodiments, a Next Generation Node B (gNB) may be configured with logical nodes, including a gNB central unit (gNB-CU) and a gNB distributed unit (gNB-DU). The gNB-CU may comprise a gNB-CU control plane (gNB-CU-CP) for control-plane functionality, and a gNB-CU user plane (gNB-CU-UP) for user-plane functionality. The gNB-CU-CP may be configured to communicate with the gNB-CU-UP over an E1 interface. The gNB-CU-UP may be configured to communicate user plane messages with the gNB-DU over an F1 user-plane interface (F1-U). The gNB-CU-CP may be configured to communicate control plane messages with the gNB-DU over an F1 control plane interface (F1-C). An apparatus of the gNB may comprise memory and processing circuitry. The processing circuitry may be configured to initiate an E1 interface setup procedure to establish the E1 interface by sending a GNB-CU-UP E1 setup request message from the gNB-CU-UP to the gNB-CU-CP. The processing circuitry may be further configured to initiate a bearer context setup procedure to establish a bearer context in the gNB-CU-UP by sending a bearer context setup request message from the gNB-CU-CP to the gNB-CU-UP over the E1 interface. The processing circuitry may be further configured to initiate a UE context setup procedure to establish UE context by sending a UE context setup request message from the gNB-CU-CP to the gNB-DU over the F1-C, the UE context including a signaling radio bearer (SRB) configuration and a data radio bearer (DRB) configuration. The processing circuitry may be further configured to transfer an initial radio-resource control (RRC) message as an uplink (UL) PDCP-PDU from the gNB-DU to the gNB-CU-CP over the F1-C. The UE context setup request message may be configured to include quality-of-service parameters for the DRB configuration. The memory may be configured to store the DRB configuration. These embodiments are described in more detail below. 
       FIG.  6    illustrates the operation of a method of communication in accordance with some embodiments. It is important to note that embodiments of the method  600  may include additional or even fewer operations or processes in comparison to what is illustrated in  FIG.  6   . In some embodiments, the method  600  may include one or more operations not shown in  FIG.  6   , including but not limited to one or more operations shown in one or more of  FIGS.  11 - 13   . 
     In addition, embodiments of the method  600  are not necessarily limited to the chronological order that is shown in  FIG.  6   . In describing the method  600 , reference may be made to one or more of  FIGS.  1 A,  1 B,  2 - 5  and  7 - 12   , although it is understood that the method  600  may be practiced with any other suitable systems, interfaces and components. 
     In some embodiments, a CU-C entity  106  may perform one or more operations of the method  600 , but embodiments are not limited to performance of the method  600  and/or operations of it by the CU-C entity  106 . In some embodiments, a gNB  105 , an eNB  104  configured to operate as a gNB  105 , an eNB  104 , a UE  102  and/or other component may perform one or more operations of the method  600  (and/or similar operations). In some embodiments, a gNB  105 , an eNB  104  configured to operate as a gNB  105 , an eNB  104 , a UE  102  and/or other component may perform one or more operations that may be reciprocal to one or more operations of the method  600 . 
     In some embodiments, the CU-C entity  106 , CU-U entity  107 , DU  108  and/or gNB  105  may be arranged to operate in accordance with a New Radio (NR) standard and/or protocol, although the scope of embodiments is not limited in this respect. While the method  600  and other methods described herein may refer to CU-C entities  106 , CU-U entities  107 , DUs  108 , eNBs  104 , gNBs  105  and/or UEs  102  operating in accordance with 3GPP standards, 5G standards, NR standards and/or other standards, embodiments of those methods are not limited to just those devices, and may also be practiced on other devices, such as a Wi-Fi access point (AP) or user station (STA). In addition, the method  600  and other methods described herein may be practiced by wireless devices configured to operate in other suitable types of wireless communication systems, including systems configured to operate according to various IEEE standards such as IEEE 802.11. The method  600  and/or other methods described herein may also be applicable to an apparatus of a CU-C entity  106 , an apparatus of a CU-U entity  107 , an apparatus of a DU  108  and/or an apparatus of a gNB  105  and/or an apparatus of another device described above. 
     It should also be noted that embodiments are not limited by references herein (such as in descriptions of the methods  600 ,  700  and  800  and/or other descriptions herein) to transmission, reception and/or exchanging of elements such as frames, messages, requests, indicators, signals or other elements. In some embodiments, such an element may be generated, encoded or otherwise processed by processing circuitry (such as by a baseband processor included in the processing circuitry) for transmission. The transmission may be performed by a transceiver or other component, in some cases. In some embodiments, such an element may be decoded, detected or otherwise processed by the processing circuitry (such as by the baseband processor). The element may be received by a transceiver or other component, in some cases. In some embodiments, the processing circuitry and the transceiver may be included in a same apparatus. The scope of embodiments is not limited in this respect, however, as the transceiver may be separate from the apparatus that comprises the processing circuitry, in some embodiments. 
     In some embodiments, the CU-C entity  106 , CU-U entity  107 , DU  108  and/or gNB  105  may be arranged to operate in accordance with a New Radio (NR) protocol and/or standard, although the scope of embodiments is not limited in this respect. 
     In some embodiments, the CU-C entity  106  may be included in a disaggregated Next Generation Node-B (gNB)  105  that comprises a central unit (CU) and a distributed unit (DU)  108 . The CU may comprise the CU-C entity  106  for control-plane functionality and the CU-U entity  107  for user-plane functionality. 
     In some embodiments, the CU-C entity  106  may be configurable for operation in which the CU-C entity  106  and the CU-U entity  107  are not co-located. In some embodiments, the CU-C entity  106  may be configurable for operation in which the CU-C entity  106  and the DU  108  are not co-located. Other arrangements are possible, including arrangements in which two or more of the CU-U entity  107 , the CU-C entity  106  and the DU  108  are co-located. 
     At operation  605 , the CU-C entity  106  may transmit, to a DU  108 , a UE context setup message that includes one or more parameters for an establishment of a data radio bearer (DRB). The UE context setup message may be included in a 3GPP standard, NR standard and/or other standard, although the scope of embodiments is not limited in this respect. Embodiments are not limited to usage of the UE context setup message in operation  605 , as any suitable message may be used. 
     In some embodiments, one or more messages exchanged between the CU-C entity  106  and the DU  108  (including but not limited to the message of operation  605 ) may be transmitted on an F1 interface, although the scope of embodiments is not limited in this respect. 
     In some embodiments, the DRB may be established for exchange of data packets between a UE  102  and the CU-U entity  107  via the DU  108 , although the scope of embodiments is not limited in this respect. 
     In some embodiments, the parameters of the UE context setup message of operation  605  may be related to one or more of: a physical (PHY) layer of the DU  108 , a medium access control (MAC) layer of the DU  108 , a radio link control (RLC) layer of the DU  108  and/or other layer. In a non-limiting example, the parameters may include one or more of: an aggregate maximum bit rate (AMBR) for the UE, a quality of service (QoS) parameter, a latency, a bit error rate, a packet error rate and/or other. 
     At operation  610 , the CU-C entity  106  may transmit, to the CU-U entity  107 , a UE context setup message that includes information related to the DRB. The UE context setup message may be included in a 3GPP standard, NR standard and/or other standard, although the scope of embodiments is not limited in this respect. Embodiments are not limited to usage of the UE context setup message in operation  610 , as any suitable message may be used. 
     In some embodiments, one or more messages exchanged between the CU-C entity  106  and the CU-U entity  107  (including but not limited to the message of operation  610 ) may be transmitted on an E1 interface, although the scope of embodiments is not limited in this respect. 
     In a non-limiting example, the UE context setup message of operation  610  may include an access stratum (AS) security key for encryption and decryption of the data packets of the DRB. Additional information and/or alternate information may be included in the message of operation  610 , in some embodiments. 
     In some embodiments, the UE context setup message of operation  610  and the UE context setup message of operation  605  may be different messages, although the scope of embodiments is not limited in this respect. 
     At operation  615 , the CU-C entity  106  may transmit, to the DU  108 , a UE context modify message. The UE context modify message may be included in a 3GPP standard. NR standard and/or other standard, although the scope of embodiments is not limited in this respect. Embodiments are not limited to usage of the UE context modify message in operation  615 , as any suitable message may be used. 
     In some embodiments, the UE context modify message may include one or more updated values of one of the parameters of the UE context setup message of operation  605 . Additional information and/or alternate information may be included, in some embodiments. 
     At operation  620 , the CU-C entity  106  may transmit, to the DU  108 , a UE context release message to indicate that the DRB is to be released. The UE context release message may be included in a 3GPP standard. NR standard and/or other standard, although the scope of embodiments is not limited in this respect. Embodiments are not limited to usage of the UE context release message in operation  620 , as any suitable message may be used. 
     At operation  625 , the CU-C entity  106  may receive, from a core network (CN), control signaling that indicates that the UE  102  is to be paged. In some embodiments, the CU-C entity  106  may receive the control signaling from a component of the CN (such as the MME  122 , SGW  124  and/or other component), although the scope of embodiments is not limited in this respect. 
     In some embodiments, the control signaling may indicate that the UE  102  is to be paged for reception of one or more downlink data packets, although the scope of embodiments is not limited in this respect. For instance, the UE  102  may be paged for other purposes, in some cases. 
     In some embodiments, the control signaling may include information related to one or more of: a paging identifier of the UE  102 , paging identifiers of a group of UEs  102  (which may include the UE  102 ), a paging occasion and/or other information. 
     At operation  630 , the CU-C entity  106  may transmit, to the DU  108 , a paging configure message. The paging configure message may be included in a 3GPP standard, NR standard and/or other standard, although the scope of embodiments is not limited in this respect. Embodiments are not limited to usage of the paging configure message in operation  630 , as any suitable message may be used. 
     In some embodiments, the paging configure message may indicate one or more of: a paging identity of the UE  102 , a paging occasion in which the UE  102  is to be paged and/or other information. 
     At operation  635 , the CU-C entity  106  may transmit, to the DU  108 , minimum system information (MSI). In some embodiments, the CU-C entity  106  may determine the MSI, although the scope of embodiments is not limited in this respect. 
     In some embodiments, the CU-C entity  106  may transmit the MSI to the DU  108  for broadcast by the DU  108 , although the scope of embodiments is not limited in this respect. In some embodiments, the MSI may include a master information block (MIB) and a type 1 SI block (SIB-1). In some embodiments, the MSI may include one or more of: an MIB, an SIB-1 and/or other. 
     At operation  640 , the CU-C entity  106  may receive, from the DU  108 , a request for on-demand system information. At operation  645 , the CU-C entity  106  may determine the on-demand system information. At operation  650 , the CU-C entity  106  may transmit, to the DU  108 , the on-demand system information. 
     In some embodiments, the CU-C entity  106  may receive the request from the DU  108 , wherein the DU  108  operates as a relay for the UE  102 . In some embodiments, the CU-C entity  106  may receive the request from the DU  108  on behalf of the UE  102 . 
     In a non-limiting example, the on-demand system information may be related to a capability of the UE  102  to camp on a cell that includes the disaggregated gNB  105 . Additional information and/or alternate information may be included in the on-demand system information, in some embodiments. In some embodiments, the on-demand system information may be specific to the UE  102 , although the scope of embodiments is not limited in this respect. 
     In some embodiments, the CU-C entity  106  may transmit the on-demand system information to the DU  108  as part of a downlink RRC message transfer. In some embodiments, the CU-C entity  106  may transmit a downlink RRC message transfer that includes the on-demand system information. The downlink RRC message transfer may be included in a 3GPP standard. NR standard and/or other standard, although the scope of embodiments is not limited in this respect. Embodiments are not limited to usage of the downlink RRC message transfer in operation  650 , as any suitable message may be used. 
     At operation  655 , the CU-C entity  106  may receive, from the CU-U entity  107 , a CU-U error indication message. The CU-U error indication message may be included in a 3GPP standard, NR standard and/or other standard, although the scope of embodiments is not limited in this respect. Embodiments are not limited to usage of the CU-U error indication message in operation  655 , as any suitable message may be used. 
     At operation  660 , the CU-C entity  106  may transmit, to the DU entity  108 , a DL RRC message transfer message. In some embodiments, the message may be intended for the UE  102  and forwarded by the DU  108 , although the scope of embodiments is not limited in this respect. The message may be used to configure, reconfigure or release RRC connection. The DL RRC message transfer message may be included in a 3GPP standard, NR standard and/or other standard, although the scope of embodiments is not limited in this respect. Embodiments are not limited to usage of the DL RRC message transfer message in operation  660 , as any suitable message may be used. 
     At operation  665 , the CU-C entity  106  may receive, from the DU entity  108 , a UL RRC message transfer message, which may encapsulate the RRC message sent by the UE  102 . The message may be used for one or more of: to report measurement results, to respond to an RRC connection request and/or other operation(s). The UL RRC message transfer message may be included in a 3GPP standard, NR standard and/or other standard, although the scope of embodiments is not limited in this respect. Embodiments are not limited to usage of the UL RRC message transfer message in operation  665 , as any suitable message may be used. 
     In some embodiments, the CU-U error indication message may indicate one or more of: a packet data convergence protocol (PDCP) outage of the DRB, a hardware failure, an unavailability of a transport resource and/or other information. Additional information and/or alternate information may be included, in some embodiments. 
     One or more of the messages described herein may be included in a standard and/or protocol, including but not limited to Third Generation Partnership Project (3GPP), 3GPP Long Term Evolution (LTE), Fourth Generation (4G), Fifth Generation (5G), New Radio (NR) and/or other. The scope of embodiments is not limited to usage of those particular messages, however. Embodiments are not limited to the names of the messages described herein. The scope of embodiments is also not limited to usage of elements that are included in standards. 
     In some embodiments, a CU-C entity  106  may comprise memory. The memory may be configurable to store information that identifies the AS security key. The memory may store one or more other elements and the apparatus may use them for performance of one or more operations. The CU-C entity  106  may include processing circuitry, which may perform one or more operations (including but not limited to operation(s) of the method  600  and/or other methods described herein). The processing circuitry may include a baseband processor. The baseband circuitry and/or the processing circuitry may perform one or more operations described herein, including but not limited to encoding of one or more UE context setup messages. The CU-C entity  106  may include a transceiver to transmit one or more UE context setup messages. The transceiver may transmit and/or receive other blocks, messages and/or other elements. 
       FIG.  7    illustrates the operation of another method of communication in accordance with some embodiments.  FIG.  8    illustrates the operation of another method of communication in accordance with some embodiments. Embodiments of the methods  700  and  800  may include additional or even fewer operations or processes in comparison to what is illustrated in  FIGS.  7 - 8    and embodiments of the methods  700  and/or  800  are not necessarily limited to the chronological order that is shown in  FIGS.  7 - 8   . In some embodiments, the method  700  may include one or more operations not shown in  FIG.  7   , including but not limited to one or more operations shown in one or more of  FIGS.  11 - 13   . In some embodiments, the method  800  may include one or more operations not shown in  FIG.  8   , including but not limited to one or more operations shown in one or more of  FIGS.  11 - 13   . 
     In describing the methods  700  and/or  800 , reference may be made to one or more of the figures described herein, although it is understood that the methods  700  and/or  800  may be practiced with any other suitable systems, interfaces and components. In addition, embodiments of the methods  700  and/or  800  may be applicable to UEs  102 , eNBs  104 , gNBs  105 , CU-C entities  106 , CU-U entities  107 . DUs  108 , APs, STAs and/or other wireless or mobile devices. The methods  700  and/or  800  may also be applicable to an apparatus of a UE  102 , eNB  104 , gNB  105 , CU-C entity  106 , CU-U entity  107 , DU  108  and/or other device described above. 
     In some embodiments, a CU-U  107  entity may perform one or more operations of the method  700 , but embodiments are not limited to performance of the method  700  and/or operations of it by the CU-U entity  107 . In some embodiments, another component (such as the CU-C entity  106 , DU  108 , gNB  105 , eNB  104  and/or other) may perform one or more operations of the method  700  (and/or similar operations). In some embodiments, another component (such as the CU-C entity  106 , DU  108 , gNB  105 , eNB  104  and/or other) may perform one or more operations that may be reciprocal to one or more operations of the method  700 . 
     In some embodiments, a DU  108  may perform one or more operations of the method  800 , but embodiments are not limited to performance of the method  800  and/or operations of it by the DU  108 . In some embodiments, another component (such as the CU-C entity  106 , CU-U entity  107 , gNB  105 , eNB  104  and/or other) may perform one or more operations of the method  800  (and/or similar operations). In some embodiments, another component (such as the CU-C entity  106 , CU-U entity  107 , gNB  105 , eNB  104  and/or other) may perform one or more operations that may be reciprocal to one or more operations of the method  800 . 
     It should be noted that one or more operations of one of the methods  600 ,  700 ,  800  may be the same as, similar to and/or reciprocal to one or more operations of the other methods. For instance, an operation of the method  600  may be the same as, similar to and/or reciprocal to an operation of the method  700 , in some embodiments. In a non-limiting example, an operation of the method  600  may include transmission of an element (such as a frame, block, message and/or other) from the CU-C entity  106  to the CU-U entity  107 , and an operation of the method  700  may include reception of a same element (and/or similar element) from the CU-C entity  106  by the CU-U entity  107 . In some cases, descriptions of operations and techniques described as part of one of the methods  600 ,  700 ,  800  may be relevant to one or both of the other methods. 
     In addition, previous discussion of various techniques and concepts may be applicable to the methods  700  and/or  800  in some cases, including but not limited to disaggregated gNB  105 , F1 interface, F1-C interface, F1-U interface, E1 interface, paging, on-demand SI, MSI, messages (including but not limited to messages described regarding the method  600 ) and/or other. In addition, the examples shown in one or more of the figures may also be applicable, in some cases, although the scope of embodiments is not limited in this respect. 
     At operation  705 , the CU-U entity  107  may receive, from the CU-C entity  106 , a UE context setup message. The UE context setup message may be included in a 3GPP standard, NR standard and/or other standard, although the scope of embodiments is not limited in this respect. Embodiments are not limited to usage of the UE context setup message in operation  705 , as any suitable message may be used. 
     In some embodiments, the UE context setup message may include information related to security of a DRB. In a non-limiting example, an AS security key may be included in the UE context setup message. 
     In some embodiments, the DRB may be at least party for communication between the UE  102  and the DU  108 , although the scope of embodiments is not limited in this respect. In some embodiments, the CU-U  107  may operate as a relay between the DU  108  and a core network (CN) for the DRB. In some embodiments, the CU-U  107  may operate as a relay between the DU  108  and one or more components of the CN for the DRB. 
     At operation  710 , the CU-U entity  107  may receive, from the DU  108 , one or more uplink data packets. In some embodiments, the CU-U entity  107  may receive the one or more uplink data packets from the DU  108  on the DRB. 
     At operation  715 , the CU-U entity  107  may decrypt the one or more uplink data packets based at least partly on the information (received from the CU-C entity  106  at operation  705 ) related to security of the DRB. In some embodiments, the CU-LU entity  107  may decrypt the one or more uplink data packets based at least partly on an AS security key included in the UE context setup message of operation  705 . 
     At operation  720 , the CU-U entity  107  may forward the one or more uplink data packets to the core network (CN). In some embodiments, the CU-U entity  107  may forward the one or more uplink data packets to one or more components of the CN. In a non-limiting example, the CU-U entity  107  may forward the one or more uplink data packets to the SGW  124 . 
     In some embodiments, the CU-U entity  107  may forward decrypted uplink data packet(s) to the CN, although the scope of embodiments is not limited in this respect. For instance, some embodiments may not necessarily include operation  715 . 
     In some embodiments, the CU-U entity  107  may be configurable for operation in which the CU-U entity  107  and the CU-C entity  106  are not co-located. In some embodiments, the CU-U entity  107  may be configurable for operation in which the CU-U entity  107  and the DU  108  are not co-located. Other arrangements are possible, including arrangements in which two or more of the CU-U entity  107 , the CU-C entity  106  and the DU  108  are co-located. 
     In some embodiments, a CU-U entity  107  may comprise memory. The memory may be configurable to store information that identifies the AS security key. The memory may store one or more other elements and the apparatus may use them for performance of one or more operations. The CU-U entity  107  may include processing circuitry, which may perform one or more operations (including but not limited to operation(s) of the method  700  and/or other methods described herein). The processing circuitry may include a baseband processor. The baseband circuitry and/or the processing circuitry may perform one or more operations described herein, including but not limited to decoding of one or more UE context setup messages. The CU-U entity  107  may include a transceiver to receive one or more UE context setup messages. The transceiver may transmit and/or receive other blocks, messages and/or other elements. 
     At operation  805 , the DU  108  may receive, from the CU-C entity  106 , a UE context setup message. The UE context setup message may be included in a 3GPP standard, NR standard and/or other standard, although the scope of embodiments is not limited in this respect. Embodiments are not limited to usage of the UE context setup message in operation  805 , as any suitable message may be used. 
     In some embodiments, the UE context setup message may configure a DRB between the UE  102  and the CU-U entity  106  via the DU  108 . In some embodiments, the UE context setup message may be used to configure a DRB between the UE  102  and the CU-U entity  106  via the DU  108 . In some embodiments, the UE context setup message may include information related to a DRB between the UE  102  and the CU-U entity  106  via the DU  108 . 
     In a non-limiting example, the UE context setup message may include one or more of: an aggregate maximum bit rate (AMBR) for the UE  102 , a quality of service (QoS) parameter, a latency, a bit error rate, a packet error rate and/or other. 
     At operation  810 , the DU  108  may receive, from the CU-C entity  106 , a UE context modify message that includes an updated value of one of the parameters of the UE context setup message. The UE context modify message may be included in a 3GPP standard, NR standard and/or other standard, although the scope of embodiments is not limited in this respect. Embodiments are not limited to usage of the UE context modify message in operation  810 , as any suitable message may be used. 
     At operation  815 , the DU  108  may receive an uplink data packet from the UE  102 . In some embodiments, the DU  108  may receive the uplink data packet from the UE  102  on the DRB, although the scope of embodiments is not limited in this respect. 
     At operation  820 , the DU  108  may transmit the uplink data packet to the CU-U entity  107 . In some embodiments, the DU  108  may forward the uplink data packet to the CU-U entity  107 . 
     In some embodiments, the DU  108  may perform one or more operations similar to operations  815 - 820  for the downlink. For instance, the DU  108  may receive a downlink data packet from CU-U that is intended for the UE  102 . The DU  108  may transmit and/or forward the downlink data packet to the UE  102 . 
     At operation  825 , the DU  108  may receive, from the CU-C entity  106 , a paging configure message. The paging configure message may be included in a 3GPP standard, NR standard and/or other standard, although the scope of embodiments is not limited in this respect. Embodiments are not limited to usage of the paging configure message in operation  825 , as any suitable message may be used. 
     In some embodiments, the paging configure message may indicate that the UE  102  is to be paged for reception of one or more downlink data packets, although the scope of embodiments is not limited in this respect. For instance, the UE  102  may be paged for other purposes, in some cases. 
     In some embodiments, the paging configure message may include information related to one or more of: a paging identifier of the UE  102 , paging identifiers of a group of UEs  102  (which may include the UE  102 ), a paging occasion and/or other information. 
     At operation  830 , the DU  108  may determine a paging occasion for the UE  102 . It should be noted that some embodiments may not necessarily include operation  830 . For instance, the paging occasion may be indicated in the paging configure message, in some embodiments. 
     At operation  835 , the DU  108  may transmit, to the UE  102 , control signaling that indicates that the UE  102  is to be paged. 
     In some embodiments, if the CU-C entity  106  and the DU  108  are synchronized, the DU  108  may transmit the control signaling in a paging occasion indicated by the paging configure message. 
     In some embodiments, if the CU-C entity  106  and the DU  108  are not synchronized, the DU  108  may determine a paging occasion for the UE  102  based on information included in the paging configure message. Such information may be related to one or more of: a paging identity of the UE  102 , a paging group of the UE  102  and/or other. The DU  108  may transmit the control signaling to the UE  102  in the determined paging occasion. 
     At operation  840 , the DU  108  may receive, from the CU-C entity  106 , minimum system information (MSI). At operation  845 , the DU  108  may transmit the MSI. In some embodiments, the DU  108  may transmit the MSI in accordance with a broadcast transmission, although the scope of embodiments is not limited in this respect. 
     At operation  850 , the DU  108  may receive, from the UE  102 , a request for on-demand system information. In a non-limiting example, the on-demand system information may be related to a capability of the UE  102  to camp on a cell that includes the disaggregated gNB  105 . Additional information and/or alternate information may be included in the on-demand system information, in some embodiments. In some embodiments, the on-demand system information may be specific to the UE  102 , although the scope of embodiments is not limited in this respect. 
     In a non-limiting example, the request from the UE  102  for the on-demand SI is included in a type-1 message (msg-1) of a random access procedure or a type-3 message (msg-3) of the random access procedure. These messages (msg-1, msg-3) may be included in a 3GPP standard, NR standard and/or other standard, although the scope of embodiments is not limited in this respect. Embodiments are not limited to usage of these messages (msg-1, msg-3) in operation  850 , as any suitable message may be used. 
     At operation  855 , the DU  108  may transmit, to the CU-C entity  106 , the request for on-demand system information. In some embodiments, the DU  108  may transmit the request to the CU-C entity  106  as part of an uplink RRC message transfer. In some embodiments, the DU  108  may transmit an uplink RRC message transfer that includes the request. The uplink RRC message transfer may be included in a 3GPP standard. NR standard and/or other standard, although the scope of embodiments is not limited in this respect. Embodiments are not limited to usage of the uplink RRC message transfer in operation  855 , as any suitable message may be used. 
     At operation  860 , the DU  108  may receive, from the CU-C entity  106 , the on-demand system information. In some embodiments, the DU  108  may receive the on-demand system information from the CU-C entity  106  as part of a downlink RRC message transfer. In some embodiments, the DU  108  may receive a downlink RRC message transfer that includes the on-demand system information. The downlink RRC message transfer may be included in a 3GPP standard, NR standard and/or other standard, although the scope of embodiments is not limited in this respect. Embodiments are not limited to usage of the downlink RRC message transfer in operation  860 , as any suitable message may be used. 
     At operation  865 , the DU  108  may determine the on-demand system information. 
     In some embodiments, one or both of operations  855 - 860  may not necessarily be included. For instance, the DU  108  may determine the on-demand information (at operation  865 ), and may not necessarily send the request to the CU-C entity  106 . 
     In some embodiments, operation  865  may not necessarily be included. For instance, the DU  108  may obtain the on-demand system information from the CU-C entity  106  at operation  860  instead of determination of the on-demand system information. 
     In some embodiments, a first portion of the on-demand system information may be determined by the DU  108  and a second portion of the on-demand system information may be received from the CU-C entity  106 . 
     At operation  870 , the DU  108  may transmit, to the UE  102 , the on-demand system information. 
     At operation  875 , the DU  108  may transmit to the CU-C entity  106 , a UL RRC message transfer message. The message may be received from the UE  102 . The message may be used for one or more of: to report measurement results, to respond to an RRC connection request and/or other operation(s). 
     At operation  880 , the DU  108  may receive from the CU-C  106 , a DL RRC message transfer message. The message may be intended for the UE  102 , although the scope of embodiments is not limited in this respect. The message may be used for one or more of: configuring an RRC connection, reconfiguring the RRC connection, releasing the RRC connection and/or other operation(s). 
     In some embodiments, the DU  108  may be configurable for operation in which the DU and the CU-U entity  107  are not co-located. In some embodiments, the DU  108  may be configurable for operation in which the CU-C entity  106  and the DU  108  are not co-located. Other arrangements are possible, including arrangements in which two or more of the CU-U entity  107 , the CU-C entity  106  and the DU  108  are co-located. 
     In some embodiments, a DU  108  may comprise memory. The memory may be configurable to store information related to a received UE context setup message. The memory may store one or more other elements and the apparatus may use them for performance of one or more operations. The DU  108  may include processing circuitry, which may perform one or more operations (including but not limited to operation(s) of the method  800  and/or other methods described herein). The processing circuitry may include a baseband processor. The baseband circuitry and/or the processing circuitry may perform one or more operations described herein, including but not limited to decoding of one or more UE context setup messages. The DU  108  may include a transceiver to receive one or more UE context setup messages. The transceiver may transmit and/or receive other blocks, messages and/or other elements. 
       FIG.  9    illustrates examples of protocol layers and functional splits in accordance with some embodiments.  FIG.  10    illustrates an example architecture in accordance with some embodiments.  FIG.  11 A  and  FIG.  11 B  illustrate example operations and example messages that may be exchanged in accordance with some embodiments. In references herein. “ FIG.  11   ” may include  FIG.  11 A  and  FIG.  11 B .  FIG.  12    illustrates additional example operations and additional example messages that may be exchanged in accordance with some embodiments.  FIG.  13    illustrates additional example operations and additional example messages that may be exchanged in accordance with some embodiments. It should be noted that the examples shown in  FIGS.  9 - 13    may illustrate some or all of the concepts and techniques described herein in some cases, but embodiments are not limited by the examples. For instance, embodiments are not limited by the name, number, type, size, ordering, arrangement and/or other aspects of the operations, messages, gNBs  105 , UEs  102 , CU-C entities  106 , CU-U entities  107 , DUs  108 , and other elements as shown in  FIGS.  9 - 13   . Although some of the elements shown in the examples of  FIGS.  9 - 13    may be included in a 3GPP LTE standard, 5G standard. NR standard and/or other standard, embodiments are not limited to usage of such elements that are included in standards. 
     Referring to  FIG.  9   , multiple elements  905 - 945  of a RAN architecture  900  are shown. Embodiments are not limited to the elements shown. In some embodiments, a RAN architecture may not necessarily include all elements shown in  FIG.  9   . In some embodiments, a RAN architecture may include one or more additional elements not shown in  FIG.  9   . In some embodiments, one or more of the elements  905 - 945  may be included in a 3GPP standard, NR standard, 5G standard and/or other standard, although the scope of embodiments is not limited in this respect. As shown in  FIG.  9   , different options (indicated by “option  1 ” through “option  8 ”) are possible for a functional split within the RAN architecture  900  (for instance, a NR base station) between central and distributed units. For instance, as indicated by  1050 , a functional split according to “option  2 ” is between the PDCP  910  and the high RLC  915 . Some descriptions herein may refer to techniques that use the split according to option  2 , but it is understood that embodiments are not limited to usage of the split according to option  2 . Some or all techniques described herein may be applicable to embodiments in which another split (including but not limited to other options shown in  FIG.  9   ) is used, in some cases. 
     Referring to  FIG.  10   , the RAN architecture  1000  includes C-plane/U-plane separation for CU. In some embodiments, NG-C and NG-U may be applicable to RAN3 arrangements. In some embodiments, SA2 arrangements may use N2 and N3 instead of NG-C and NG-U, respectively. 
     In some embodiments, a control plane (CP) of a Next Generation Node-B (gNB)  105  may use and/or include RRC  1032  and PDCP  1034  of the signaling radio bearer (SRB), which may be included into a control central unit (CU-C)  1030 . In some embodiments, a user plane (UP) of the gNB  105  may include RLC  1012 , MAC  1014  and PHY  1016 , which may be deployed in the distributed unit (DU)  1010 , while PDCP of the data radio bearer (DRB) (shown as PDCP-U  1044 ) and service data application protocol (SDAP)  1042  may be included in another CU (CU-U)  1040 . The RAN  1000  may include one or more interfaces (including but not limited to  1020 ,  1022 ,  1050 ,  1060 ,  1062 ). 
     In some embodiments, the CU-C  1030  may perform one or more control functions and may support the PDCP of SRB (shown as PDCP-C  1034 ). In some embodiments, RRC  1032  and/or NGAP of one or more UEs  102  may be performed by the CU-C  1030 . In some embodiments, functionality related to access/mobility management and performance optimization, including but not limited to RRM, may be implemented in a central manner in CU-C  1030 . In some cases, the CU-C  1030  may have a global view of the network. 
     In some embodiments, the user-plane central unit (CU-U)  1040  may terminate GTP-U (such as the NG-U interface  1062 ) towards 5GC  1070 . The CU-C  1030  may perform one or more operations related to SDAP. A non-limiting example of such an operation is mapping between QoS flows and DRBs. Such a mapping may be included in a 5G arrangement and/or NR arrangement, although the scope of embodiments is not limited in this respect. In some embodiments, the CU-C  1040  may perform one or more operations related to PDCP of DRB (indicated by PDCP-U  1044 ). In some embodiments, CU-U  1040  may perform one or more operations related to PDCP of SRB. In a non-limiting example, the CU-U  1040  may be configured by the CU-C  1030  to perform one or more operations related to PDCP of SRB. 
     In some embodiments, the distributed unit (DU)  1010  may perform one or more operations related to RLC  1012 , PHY  1014  and/or MAC  1016 . 
     In some embodiments, the 5GC may operate as a mobility anchor and/or gateway for different services. 
     In some embodiments, the E1 interface  1050  may perform one or more of: communicate messages between CU-C  1030  and CU-U  1040  (including but not limited to messages to set up UE context); configure GTP-U end points, SDAP  1042 , and PDCP of DRB/SRB; transfer RRC messages; and/or other. 
     In some embodiments, the F1-C interface  1020  may perform one or more of: communicate messages between CU-C  1030  and DU  1010 , including but not limited to messages to configure PHY  1014 , MAC  1016  and RLC  1012 : transfer PDCP PDU of RRC messages; and/or other. 
     In some embodiments, the F1-U interface  1022  may perform one or more of: transfer PDCP PDU of DRB/SRB between CU-U  1040  and the DU  1010 . 
     In some embodiments, the NG-U interface  1062  (and/or N3 interface) may perform one or more of: transfer GTP-U between 5GC  1070  and CU-U  1040 ; and/or other. In some embodiments, the NG-C interface  1060  may perform one or more of: communicate control messages between CU-C  1030  and 5GC  1070 ; and/or other. 
     In some embodiments, one or more messages may be exchanged between two or more of the elements shown in  FIG.  10   . In a non-limiting example, such messages may be part of an F1-AP (an application protocol used on the control plane of the F1 interface). Example messages are shown in the table below. The direction of the messages (such as which components may exchange the messages) are also shown. In addition, example fields are also shown. Embodiments are not limited to the message names shown in the table. Embodiments are also not limited to the fields shown in the table or to the field names shown in the table. In some embodiments, one or more additional fields may be used in one or more messages. In some embodiments, a message shown in the table may not necessarily include all corresponding fields shown in the table. 
     
       
         
           
               
               
               
             
               
                   
               
               
                 Message name 
                 Direction 
                 Main fields included 
               
               
                   
               
             
            
               
                 DU capability 
                 DU→CU-C 
                 Supported antenna and MIMO modes, supported 
               
               
                 indication 
                   
                 frequency bands, hardware capacity (including 
               
               
                   
                   
                 computing and networking interface), and/or other. 
               
               
                 DU configure 
                 CU-C → DU 
                 Radio frame structure (including scheduling of System 
               
               
                   
                   
                 Information Block). antenna installation, system 
               
               
                   
                   
                 Information intended for UE including Master 
               
               
                   
                   
                 Information Block (MIB), System Information Block 
               
               
                   
                   
                 (SIB) type x: x = 1, 2, 3, . . . similar to those defined in 
               
               
                   
                   
                 TS36.331, and/or other. 
               
               
                 DU error indication 
                 DU → CU-C 
                 Cause of error, including hardware failure, outage of 
               
               
                   
                   
                 radio bearer, transport resource unavailable, and/or 
               
               
                   
                   
                 other. 
               
               
                 Paging configure 
                 CU-C → DU 
                 Paging message from NG-Core to a specific group of 
               
               
                   
                   
                 UEs including UE Paging Identity chosen from S-TMSI or 
               
               
                   
                   
                 IMSI, message to notify the system information change or 
               
               
                   
                   
                 ETWS. 
               
               
                 Radio bearer 
                 CU-C → DU 
                 UE Identity, signaling radio bearer (SRB)/data radio 
               
               
                 configure 
                   
                 bearer (DRB) ID, Transport layer address of CU-U, all 
               
               
                   
                   
                 parameters of RLC, MAC and PHY that similar to 
               
               
                   
                   
                 those defined in 3GPP 36.331, such as RLC, MAC 
               
               
                   
                   
                 and PHY configure, and MAC control element (CE), 
               
               
                   
                   
                 and/or other. 
               
               
                 UE context setup 
                 CU-C → DU 
                 UE identity, UE Aggregate Maximum Bit Rate (AMBR), 
               
               
                   
                   
                 QoS parameters implemented by the MAC layer (e.g. 
               
               
                   
                   
                 maximum latency, bit/packet error rate), and/or other. 
               
               
                 UE context modify 
                 CU-C → DU 
                 UE identity, UE AMBR, QoS parameters implemented 
               
               
                   
                   
                 by the MAC layer (e.g. maximum latency, bit/packet 
               
               
                   
                   
                 error rate), and/or other. 
               
               
                 UE context release 
                 CU-C → DU 
                 UE Identity 
               
               
                 UL RRC message 
                 DU → CU-C 
                 UE Identity, RRC PDCP PDU or RRC PDU 
               
               
                 transfer 
               
               
                 DL RRC message 
                 CU-C → DU 
                 UE Identity, RRC PDCP PDU or RRC PDU 
               
               
                 transfer 
               
               
                   
               
            
           
         
       
     
     In some embodiments, a recipient (including but not limited to one of the elements shown in  FIG.  10   ) may send a response and/or acknowledgement in response to a message from a sender (including but not limited to one of the elements shown in  FIG.  10   ). In some embodiments, the CU-C  1030  may issue two kinds of paging configuration messages, depending on whether DU  1010  and CU-C  1030  are synchronized. 
     In some embodiments, if the DU  1010  and CU-C  1030  are synchronized and CU-C  1030  is aware of a paging occasion of a UE group, a related paging configuration message may include one or more of: the paging occasion that is intended for DU  1010 , one or more UE paging identities, and/or other. In some cases, the UE paging identities may be transparently transferred to the intended UEs  102  by DU  1010 . 
     In some embodiments, if the DU  1010  and the CU-C  1030  are not synchronized, the paging configuration message may include one or more UE paging identities. The DU  1010  may perform one or more of: grouping the corresponding UEs  102  according to their radio identities (including but not limited to C-RNTI), determining a paging occasion for each UE group, forming and sending over-the-air paging message for each UE group; and/or other. 
     In some embodiments, there may be at least two categories of system information (SI) that are to be delivered to the UE  102 : minimum SI and on-demand SI. In some embodiments, minimum SI intended for a UE  102  may be formed by DU  1010  based at least partly on information included in a DU configuration message (and/or other message) received at the DU  1010  from the CU-C  1030 . 
     In some embodiments, the minimum SI intended for UE  102  may be formed by the CU-C  1030  and may be included in a cell configuration message and/or other message sent by the CU-C  1030 . The DU  1010  may determine an occasion to send the message. 
     In some embodiments, minimum SI intended for the UE  102  may be formed by CU-C  1030 . The minimum SI may also indicate to DU  1010  an occasion in which the SI is to be sent to the UE  102 . 
     In some embodiments, on-demand SI may be formed by CU-C  1030  based at least partly on a request from the UE  102 . The on-demand SI may be sent to the DU  1010  in a message, including but not limited to a DL RRC message. The DU  1010  may receive the on-demand SI request from the UE  102  (such as in msg1 or msg3) and may send a message (including but not limited to an F1-AP on-demand SI request) to the CU-C  1030 . The CU-C  1030  may respond with a message (including but not limited to a DL RRC message transfer F1-AP message). This message may include the SI information. 
     In some embodiments, if the on-demand SI is requested by msg1 or unencrypted msg3, the DU  1010  may generate the SI information and may send it to the UE  102 . In some cases, relevant SI information may have already been configured in the DU  1010  (such as through usage of F1-AP signaling, OAM and/or other). 
     In some embodiments, one or more messages may be exchanged between two or more of the elements shown in  FIG.  10   . In a non-limiting example, such messages may be part of an E1-AP (an application protocol used on the E1 interface). Example messages are shown in the table below. The direction of the messages (such as which components may exchange the messages) are also shown. In addition, example fields are also shown. Embodiments are not limited to the message names shown in the table. Embodiments are also not limited to the fields shown in the table or to the field names shown in the table. In some embodiments, one or more additional fields may be used in one or more messages. In some embodiments, a message shown in the table may not necessarily include all corresponding fields shown in the table. 
     
       
         
           
               
               
               
             
               
                   
               
               
                 Message name 
                 Direction 
                 Main fields included 
               
               
                   
               
             
            
               
                 E1 interface setup 
                 CU-C −&gt; 
                 CU-U id, potentially also global CU-C id. 
               
               
                   
                 CU-U or 
                 May also include CU-U capabilities (see below). 
               
               
                   
                 CU-U −&gt; 
                 Message exchange: E1 Setup Request, E1 Setup 
               
               
                   
                 CU-C 
                 Response, E1 Setup Failure. 
               
               
                 CU-U capability 
                 CU-U → 
                 Supported number of UEs (e.g. 100 UE with 1 Gbps each), 
               
               
                 indication 
                 CU-C 
                 supported networking interfaces (e.g. 20X10GE, 10X1GE), 
               
               
                   
                   
                 supported encryption/integrity protection algorithms, etc. 
               
               
                 CU-U error 
                 CU-U → 
                 Cause of error, including outage of PDCP entity for a 
               
               
                 indication 
                 CU-C 
                 specific radio bearer, hardware failure, transport resource 
               
               
                   
                   
                 unavailable, etc. 
               
               
                 Reset 
                 CU-U −&gt; 
                 PDCP-U id or DRB ID, TEID. 
               
               
                   
                 CU-C or 
                 Used to initialize PDCP-U or GTP-U entity after node setup 
               
               
                   
                 CU-C −&gt; 
                 or after any failure events 
               
               
                   
                 CU-U 
               
               
                 CU-U configure 
                 CU-C → 
                 Networking address of interfaces on F1-U/NG-U, 
               
               
                   
                 CU-U 
                 encryption/integrity protection algorithms in use, 
               
               
                   
                   
                 percentage of dormant computing resource for energy 
               
               
                   
                   
                 saving etc. 
               
               
                 Radio bearer 
                 CU-C → 
                 UE identity, SDAP configure, DRB ID, DRB/SRB configure 
               
               
                 configure 
                 CU-U 
                 (PDCP configure), Transport layer/network address of DU. 
               
               
                   
                   
                 May also include 
               
               
                 UE context setup 
                 CU-C → 
                 UE identity, AS Security keys, DRB/SRB configure 
               
               
                   
                 CU-U 
               
               
                 UE context modify 
                 CU-C → 
                 UE identity, AS security keys, DRB/SRB configure 
               
               
                   
                 CU-U 
               
               
                 UE context 
                 CU-C → 
                 UE Identity 
               
               
                 release 
                 CU-U 
               
               
                 GTP-U end point 
                 CP-C → 
                 UE Identity, TEID, DRB ID, Transport layer/network 
               
               
                 configure 
                 CU-U 
                 address of 5GC 
               
               
                 UL RRC message 
                 CU-U → 
                 UE Identity, RRC PDU 
               
               
                 transfer 
                 CU-C 
               
               
                 DL RRC message 
                 CU-C → 
                 UE Identity, RRC PDU 
               
               
                 transfer 
                 CU-U 
               
               
                   
               
            
           
         
       
     
     In some embodiments, a recipient (including but not limited to one of the elements shown in  FIG.  10   ) may send a response and/or acknowledgement in response to a message from a sender (including but not limited to one of the elements shown in  FIG.  10   ). 
     In some embodiments, security key&#39;s used by CU-U  1030  for encryption/integrity protection may be configured by CU-C  1030  in a message. In some embodiments, the CU-C  1040  may transmit the message to the CU-U  1040 . In a non-limiting example, the message may be a UE context setup/modify message. In some embodiments, the message may be sent as part of an initial AS security establishment. In some embodiments, the message may be sent as part of a change of security keys. 
     
       
         
           
               
               
               
             
               
                   
               
               
                 Message name 
                 Direction 
                 Main fields included 
               
               
                   
               
             
            
               
                 E1 interface setup 
                 CU-C −&gt; 
                 CU-U id. Potentially also global CU-C id. 
               
               
                   
                 CU-U or 
                 May also include CU-U capabilities (see below). 
               
               
                   
                 CU-U −&gt; 
                 Message exchange: E1 Setup Request, E1 Setup Response, E1 
               
               
                   
                 CU-C 
                 Setup Failure. 
               
               
                 CU-U capability 
                 CU-U → 
                 Supported number of UEs (e.g. 100 UE with 1 Gbps each) 
               
               
                 indication 
                 CU-C 
               
               
                 CU-U error 
                 CU-U → 
                 Cause of error, including outage of PDCP entry for a specific radio 
               
               
                 indication 
                 CU-C 
                 bearer, hardware failure, transport resource unavailable, etc. 
               
               
                 Reset 
                 CU-U −&gt; 
                 PDCP-U id or DRB ID. TEID. 
               
               
                   
                 CU-C or 
                 Used to initialize PDCP-U or GTP-U entity after node setup or 
               
               
                   
                 CU-C −&gt; 
                 after any failure events. 
               
               
                   
                 CU-U 
               
               
                 CU-U configure 
                 CU-C → 
                 Networking address of interfaces on F1-U/NG-U, encryption/ 
               
               
                   
                 CU-U 
                 integrity protection algorithms in use. 
               
               
                   
                   
                 Percentage of dormant computing resource for energy saving 
               
               
                   
                   
                 etc. 
               
               
                 Radio bearer 
                 CU-C → 
                 UE identity, SDAP configure, DRB ID, DRB/SRB configure (PDCP 
               
               
                 configure 
                 CU-U 
                 configure). Transport layer/network address of DU May also 
               
               
                   
                   
                 include 
               
               
                 UE context setup 
                 CU-C → 
                 UE identity, AS Security keys, DRB/SRB configure 
               
               
                   
                 CU-U 
               
               
                 UE context modify 
                 CU-C → 
                 UE identity, AS security keys, DRB/SRB configure 
               
               
                   
                 CU-U 
               
               
                 UE context release 
                 CU-C→ 
                 UE identity 
               
               
                   
                 CU-U 
               
               
                 GTP-U end point 
                 CP-C → 
                 UE Identity, TEID, DRB ID, Transport layer/network address of 
               
               
                 configure 
                 CU-U 
                 5GC 
               
               
                 UL RRC message 
                 CU-U → 
                 UE Identity, RRC PDU 
               
               
                 transfer 
                 CU-C 
               
               
                 DL RRC message 
                 CU-C → 
                 UE Identity, RRC PDU 
               
               
                 transfer 
                 CU-U 
               
               
                   
               
            
           
         
       
     
     In some embodiments, a recipient (including but not limited to one of the elements shown in  FIG.  10   ) may send a response and/or acknowledgement in response to a message from a sender (including but not limited to one of the elements shown in  FIG.  10   ). 
     In some embodiments, security keys used by CU-U  1040  for encryption/integrity protection may be configured by CU-C  1030  in a message. In some embodiments, the CU-C  1040  may transmit the message to the CU-U  1040 . In a non-limiting example, the message may be a UE context setup/modify message. In some embodiments, the message may be sent as part of an initial AS security establishment. In some embodiments, the message may be sent as part of a change of security keys. 
     Referring to  FIG.  11   , an example  1100  is shown. In some embodiments, the example  1100  may be for one or more of: RRC connection establishment, RRC connection reconfiguration, security activation and/or other. The scope of embodiments is not limited in this respect, however, as one or more of the operations shown in  FIG.  11    may be performed as part of other procedures/processes/methods. In some embodiments, one or more operations shown in  FIG.  11    may be performed during an initial attach. In some embodiments, the example  1100  may be based at least partly on F1-U based on GTP-U. A TEID may include information regarding the identity of radio bearers. In the example  1100 , one or more of the messages included in the above tables may be exchanged between DU  1010 , CU-C  1030  and/or CU-U  1040 . In some embodiments, various RRC messages (such as  1110 - 1114  and/or other) may be exchanged between the DU  1010  and the UE  102 . In some embodiments, various RRC messages (such as  1121 - 1127  and/or other) may be exchanged between the DU  1010  and the CU-C  1030 . 
     Referring to  FIG.  12   , an example  1200  is shown. In some embodiments, the example  1200  may be for intra CU-U handover. The scope of embodiments is not limited in this respect, however, as one or more of the operations shown in  FIG.  12    may be performed as part of other procedures/processes/methods. In the example  1200 , one or more of the messages included in the above tables may be exchanged between the UE  102 , source DU  1010 , target DU  1010 , CU-C  1030  and/or CU-U  1040 . In some embodiments, the handover may be from source DU  1010  to target DU  1010 . In some embodiments, as part of the intra CU-U handover, the same CU-U  1040  may be used before and after the handover. 
     In some embodiments, a measurement operation (indicated by  1205 ) may include one or more of: transmission of a measurement report from UE  102  to source DU  1010 : a UL RRC message transfer from source DU  1010  to CU-C  1030 ; and/or other. The measurement operation may at least partly trigger the handover procedure, in some embodiments. 
     In some embodiments, after a handover decision has been made by the CU-C  1030  (as indicated by  1210 ), the CU-C  1030  may send an RB configure message (as indicated by  1215 ) via E1 to CU-U  1040 . In a non-limiting example, the RB configure message  1215  may indicate that a transport layer/network address is to change from source DU  1010  to target DU  1010 . 
     In some embodiments, the CU-C  1030  may send a UE context setup message and/or RB configure message (as indicated by  1220 ) via F1-C to target DU  1010 . In a non-limiting example, the message(s) indicated by  1220  may be used to set up UE context and radio bearers. 
     In some embodiments, the CU-C  1030  may send a DL RRC message (as indicated by  1212 ) via F1-C to source DU  1010 . In a non-limiting example, the message may include information related to RRC connection reconfiguration. 
     In some embodiments, the source DU  1010  may send an RRC message (as indicated by  1213 ) to the UE  102 . In some embodiments, the DU  1010  may transparently transfer the message  1212  to the UE  102 . 
     In some embodiments, the UE context setup and RB configure message (indicated by  1220 ) sent from CU-C  1030  to target DU  1010  may be included in one message (including but not limited to a combined message). In some embodiments, the UE context setup and RB configure message (indicated by  1220 ) sent from CU-C  1030  to target DU  1010  may be separate messages. 
     Referring to  FIG.  13   , an example  1300  is shown. In some embodiments, the example  1300  may be for inter CU-U handover. The scope of embodiments is not limited in this respect, however, as one or more of the operations shown in  FIG.  13    may be performed as part of other procedures/processes/methods. In the example  1300 , one or more of the messages included in the above tables may be exchanged between the UE  102 , source DU  1010 , target DU  1010 , CU-C  1030 , source CU-U  1040  and/or target CU-U  1040 . In some embodiments, the handover may be from source DU  1010  to target DU  1010 . In some embodiments, as part of the inter CU-U handover, the source CU-U  1040  may be used before the handover and the target CU-U  1040  may be used after the handover. 
     In some embodiments, as indicated by  1310 , the UE context may be set up in the target CU-U  1040 . 
     In some embodiments, a user plane and control plane of a radio access system may be separated. The system may include at least the CU-C  1030 , the CU-U As  40  and the DU  1010 . 
     In some embodiments, the CU-C  1030  may perform one or more of: radio resource control for UE  102 , composition of RRC messages to UE  102  for connection control, handover, measurement. UE capability enquiry and/or other; transfer of NAS message between UE  102  and the core network: reception and analysis of RRC messages from UE  102  (such as measurement report, RRC connection request, acknowledgement of commands issued by the controller and/or other); issue of response(s); initiation of handover; performance of air interface control (such as cell configuration, setting up/modifying/deleting radio bearers that transfer data or signaling with UE  102 , setting up/releasing UE context and/or other); performance of radio resource management (such as admission control, load balancing, mobility control and/or other); implementation of NG2 AP with the core network to support mobility management and session management; performance of CU-U control; intra-CU mobility management; load balancing; support of inter-CU mobility and/or other. 
     In some embodiments, the CU-U  1040  may control transfer of data between UE  102  (via DU  1010 ) and NG-Core. 
     In some embodiments, the DU  1010  may transfer control-plane messages and user data towards UE  102 . 
     In some embodiments, the system may comprise an interface between CU-C  1030  and CU-U  1040  that may transfer signaling to support part of the functions at CU-C  1030  and CU-U  1040 . In some embodiments, the system may comprise an interface between the CU-C  1030  and DU  1010  that transfers signaling to support part of the functions at CU-C  1030  and DU  1010 . In some embodiments, the system may comprise an interface between CU-C  1030  and DU  1010  that transfers signaling/data to support part of the functions at CU-C  1030  and DU  1010 . 
     In some embodiments, the CU-C  1030  may perform function(s) related to one or more of: PDCP of SRB, RRC, RRM, NG2 AP, inter-gNB AP and/or other control functions. In some embodiments, the CU-U  1040  may perform function(s) related to one or more of: SDAP. PDCP of DRB (or SRB) and GTP-U end point. In some embodiments, the DU  1010  may perform function(s) related to one or more of: RLC, MAC and PHY. 
     In Example 1, an apparatus of a Next Generation Node-B (gNB) may comprise processing circuitry. The apparatus may further comprise memory. The gNB may be configured with logical nodes including a gNB central unit (gNB-CU) and a gNB distributed unit (gNB-DU). The gNB-CU may comprise a gNB-CU control plane (gNB-CU-CP) for control-plane functionality, a gNB-CU user plane (gNB-CU-UP) for user-plane functionality. The gNB-CU-CP may be configured to communicate with the gNB-CU-UP over an E1 interface. The gNB-CU-UP may be configured to communicate user plane messages with the gNB-DU over an F1 user-plane interface (F1-U). The gNB-CU-CP may be configured to communicate control plane messages with the gNB-DU over an F1 control plane interface (F1-C). The processing circuitry may be configured to initiate an E1 interface setup procedure to establish the E1 interface by sending a GNB-CU-UP E1 setup request message from the gNB-CU-UP to the gNB-CU-CP. The processing circuitry may be further configured to initiate a bearer context setup procedure to establish a bearer context in the gNB-CU-IP by sending a bearer context setup request message from the gNB-CU-CP to the gNB-CU-UP over the E1 interface. The processing circuitry may be further configured to initiate a UE context setup procedure to establish UE context by sending a UE context setup request message from the gNB-CU-CP to the gNB-DU over the F1-C, the UE context including a signaling radio bearer (SRB) configuration and a data radio bearer (DRB) configuration. The processing circuitry may be further configured to transfer an initial radio-resource control (RRC) message as an uplink (UL) PDCP-PDU from the gNB-DU to the gNB-CU-CP over the F1-C. The UE context setup request message may be configured to include quality-of-service parameters for the DRB configuration. The memory may be configured to store the DRB configuration. 
     In Example 2, the subject matter of Example 1, wherein the gNB-DU may be configured to host radio-link control (RLC), medium-access control (MAC) and physical (PHY) layers of the gNB. The gNB-DU may be configured to communicate with user equipment over a user interface (uu). 
     In Example 3, the subject matter of one or any combination of Examples 1-2, wherein the bearer context setup procedure may be performed after completion of the E1 interface setup procedure. 
     In Example 4, the subject matter of one or any combination of Examples 1-3, wherein the processing circuitry may be further configured to transfer an RRC message as a downlink (DL) Packet Data Convergence Protocol (PDCP) Protocol Data Unit (PDU) to the gNB-DU from the gNB-CU-CP over the F1-C. 
     In Example 5, the subject matter of one or any combination of Examples 1-4, wherein the UE context setup request message may further include one or more of: an aggregate maximum bit rate (AMBR), a latency, a bit error rate, and a packet error rate. 
     In Example 6, the subject matter of one or any combination of Examples 1-5, wherein the processing circuitry may be further configured to send to the gNB-DU, a UE context modify request message that includes an updated value of one of the parameters of the UE context setup request message. 
     In Example 7, the subject matter of one or any combination of Examples 1-6, wherein the processing circuitry may be further configured to send to the gNB-DU on the F1 interface, a UE context release request message to indicate that a DRB is to be released. 
     In Example 8, the subject matter of one or any combination of Examples 1-7, wherein the gNB-CU-CP may be configured to send to the gNB-CU-UP, a second UE context setup request message that includes an access stratum (AS) security key for encryption and decryption of the data packets of the DRB. 
     In Example 9, the subject matter of one or any combination of Examples 1-8, wherein the processing circuitry may be further configured to receive, from a core network (CN), control signaling that indicates that the UE is to be paged for reception of a downlink data packet. The processing circuitry may be further configured to send to the gNB-DU, a paging configure message that indicates: a paging identity of a UE, or a paging occasion of in which the UE is to be paged. 
     In Example 10, the subject matter of one or any combination of Examples 1-9, wherein the processing circuitry may be further configured to send to the gNB-DU for broadcast, minimum system information (SI) that includes a master information block (MIB) and a type 1 SI block (SIB-1). 
     In Example 11, the subject matter of one or any combination of Examples 1-10, wherein the processing circuitry may be further configured to receive, from the gNB-DU, a request from a UE for on-demand system information (SI) related to a capability of the UE to camp on a cell that includes the disaggregated gNB. The processing circuitry may be further configured to send to the gNB-DU on the F1 interface, a downlink RRC message transfer that includes the on-demand SI. 
     In Example 12, the subject matter of one or any combination of Examples 1-11, wherein the processing circuitry may be further configured to receive, from the gNB-DU, an uplink RRC message transfer that includes one or more measurement reports or a response to an RRC connection request from the UE. The processing circuitry may be further configured to send to the gNB-DU on the F1 interface, a downlink RRC message transfer to configure, reconfigure, or release an RRC connection at the UE. 
     In Example 13, a computer-readable storage medium may store instructions for execution by processing circuitry of a Next Generation Node-B (gNB). The gNB may be configured with logical nodes including a gNB central unit (gNB-CU) and a gNB distributed unit (gNB-DU). The gNB-CU may comprise a gNB-CU control plane (gNB-CU-CP) for control-plane functionality, a gNB-CU user plane (gNB-CU-UP) for user-plane functionality. The gNB-CU-CP may be configured to communicate with the gNB-CU-UP over an E1 interface, the gNB-CU-UP configured to communicate user plane messages with the gNB-DU over an F1 user-plane interface (F1-U). The gNB-CU-CP may be configured to communicate control plane messages with the gNB-DU over an F1 control plane interface (F1-C). The operations may configure the processing circuitry to initiate an E1 interface setup procedure to establish the E1 interface. The operations may further configure the processing circuitry to initiate an error indication procedure to indicate a cause of error for a UE. The operations may further configure the processing circuitry to initiate a bearer context setup procedure to establish a bearer context in the gNB-CU-UP by sending a bearer context setup request message from the gNB-CU-CP to the gNB-CU-UP over the E1 interface. The operations may further configure the processing circuitry to initiate a UE context setup procedure to establish UE context by sending a UE context setup request message from the gNB-CU-CP to the gNB-DU over the F1-C, the UE context including a signaling radio bearer (SRB) and a data radio bearer (DRB) configuration. The operations may further configure the processing circuitry to transfer an initial radio-resource control (RRC) message as an uplink (UL) PDCP-PPDU from the gNB-DU to the gNB-CU-CP over the F1-C. The UE context setup request message may be configured to include quality-of-service parameters for the DRB configuration. 
     In Example 14, the subject matter of Example 13, wherein the gNB-DU may be configured to host radio-link control (RLC), medium-access control (MAC) and physical (PHY) layers of the gNB. The gNB-DU may be configured to communicate with User Equipment (UE) over a user interface (uu). 
     In Example 15, the subject matter of one or any combination of Examples 13-14, wherein the bearer context setup procedure may be performed after completion of the E1 interface setup procedure. 
     In Example 16, the subject matter of one or any combination of Examples 13-15, wherein the operations may further configure the processing circuitry to transfer an RRC message as a downlink (DL) PDCP-PDU to the gNB-DU from the gNB-CU-CP over the F1-C. 
     In Example 17, the subject matter of one or any combination of Examples 13-16, wherein the UE context setup request message may further include one or more of, an aggregate maximum bit rate (AMBR), a latency, a bit error rate, and a packet error rate. 
     In Example 18, the subject matter of one or any combination of Examples 13-17, wherein the operations may further configure the processing circuitry to initiate the E1 interface setup procedure by: sending a GNB-CU-UP E1 setup request message from the gNB-CU-UP to the gNB-CU-CP; or sending a GNB-CU-CP E1 setup request message from the gNB-CU-CP to the gNB-CU-UP. 
     In Example 19, an apparatus of a Next Generation Node-B (gNB) may comprise processing circuitry. The apparatus may further comprise memory. The gNB may be configured with logical nodes including a gNB central unit (gNB-CU) and a gNB distributed unit (gNB-DU). The gNB-CU may comprise a gNB-CU control plane (gNB-CU-CP) for control-plane functionality, a gNB-CU user plane (gNB-CU-UP) for user-plane functionality. The gNB-CU-CP may be configured to communicate with the gNB-CU-UP over an E1 interface. The gNB-CU-UP may be configured to communicate user plane messages with the gNB-DU over an F1 user-plane interface (F1-U). The gNB-CU-CP may be configured to communicate control plane messages with the gNB-DU over an F1 control plane interface (F1-C). The processing circuitry may be configured to initiate a UE context setup procedure to establish UE context by sending a UE context setup request message from the gNB-CU-CP to the gNB-DU over the F1-C, the UE context including a signaling radio bearer (SRB) and a data radio bearer (DRB) configuration. The processing circuitry may be further configured to transfer an initial radio-resource control (RRC) message as an uplink (UL) PDCP-PPDU from the gNB-DU to the gNB-CU-CP over the F1-C. The processing circuitry may be further configured to transfer another RRC message as a downlink (DL) PDCP-PDU to the gNB-DU from the gNB-CU-CP over the F1-C. The UE context setup request message may be configured to include quality-of-service parameters for the DRB configuration. The memory may be configured to store the DRB configuration. 
     In Example 20, the subject matter of Example 19, wherein the gNB-DU may be configured to host radio-link control (RLC), medium-access control (MAC) and physical (PHY) layers of the gNB. The gNB-DU may be configured to communicate with User Equipment (UE) over a user interface (uu). 
     In Example 21, the subject matter of one or any combination of Examples 19-20, wherein the processing circuitry may be further configured to initiate an E1 interface setup procedure to establish the E1 interface by sending a GNB-CU-UP F1 setup request message from the gNB-CU-UP to the gNB-CU-CP or by sending a GNB-CU-CP E1 setup request message from the gNB-CU-CP to the gNB-CU-UP. The processing circuitry may be further configured to initiate an error indication procedure to indicate the cause of error for a UE. The processing circuitry may be further configured to initiate a bearer context setup procedure to establish a bearer context in the gNB-CU-UP by sending a bearer context setup request message from the gNB-CU-CP to the gNB-CU-UP over the E1 interface. The bearer context setup procedure may be performed after completion of the E1 interface setup procedure. 
     In Example 22, the subject matter of one or any combination of Examples 19-21, wherein the gNB-CU-CP may be configured to send, to the gNB-CU-UP, another UE context setup request message that includes an access stratum (AS) security key for encryption and decryption of the data packets of the DRB. 
     In Example 23, the subject matter of one or any combination of Examples 19-22, wherein the UE context setup request message may further include one or more of: an aggregate maximum bit rate (AMBR), a latency, a bit error rate, and a packet error rate. 
     In Example 24, a Next Generation Node-B (gNB) may be configured with logical nodes including a gNB central unit (gNB-CU) and a gNB distributed unit (gNB-DU). The gNB-CU may comprise a gNB-CU control plane (gNB-CU-CP) for control-plane functionality, a gNB-CU user plane (gNB-CU-UP) for user-plane functionality. The gNB-CU-CP may be configured to communicate with the gNB-CU-UP over an E1 interface. The gNB-CU-UP may be configured to communicate user plane messages with the gNB-DU over an F1 user-plane interface (F1-U). The gNB-CU-CP may be configured to communicate control plane messages with the gNB-DU over an F1 control plane interface (F1-C). An apparatus of the gNB may comprise means for initiating an E1 interface setup procedure to establish the E1 interface. The apparatus may further comprise means for initiating an error indication procedure to indicate a cause of error for a UE. The apparatus may further comprise means for initiating a bearer context setup procedure to establish a bearer context in the gNB-CU-UP by sending a bearer context setup request message from the gNB-CU-CP to the gNB-CU-UP over the E1 interface. The apparatus may further comprise means for initiating a UE context setup procedure to establish UE context by sending a UE context setup request message from the gNB-CU-CP to the gNB-DU over the F1-C, the UE context including a signaling radio bearer (SRB) and a data radio bearer (DRB) configuration. The apparatus may further comprise means for transferring an initial radio-resource control (RRC) message as an uplink (UL) PDCP-PPDU from the gNB-DU to the gNB-CU-CP over the F1-C. The UE context setup request message may be configured to include quality-of-service parameters for the DRB configuration. 
     In Example 25, the subject matter of Example 24, wherein the gNB-DU may be configured to host radio-link control (RLC), medium-access control (MAC) and physical (PHY) layers of the gNB. The gNB-DU may be configured to communicate with User Equipment (UE) over a user interface (uu). 
     In Example 26, the subject matter of one or any combination of Examples 24-25, wherein the bearer context setup procedure may be performed after completion of the E1 interface setup procedure. 
     In Example 27, the subject matter of one or any combination of Examples 24-26, wherein the apparatus may further comprise means for transferring an RRC message as a downlink (DL) PDCP-PDU to the gNB-DU from the gNB-CU-CP over the F1-C. 
     In Example 28, the subject matter of one or any combination of Examples 24-27, wherein the UE context setup request message may further include one or more of: an aggregate maximum bit rate (AMBR), a latency, a bit error rate, and a packet error rate. 
     In Example 29, the subject matter of one or any combination of Examples 24-28, wherein the apparatus may further comprise means for initiating the E1 interface setup procedure by: sending a GNB-CU-UP E1 setup request message from the gNB-CU-UP to the gNB-CU-CP; or sending a GNB-CU-CP E1 setup request message from the gNB-CU-CP to the gNB-CU-UP. 
     The Abstract is provided to comply with 37 C.F.R. Section 1.72(b) requiring an abstract that will allow the reader to ascertain the nature and gist of the technical disclosure. It is submitted with the understanding that it will not be used to limit or interpret the scope or meaning of the claims. The following claims are hereby incorporated into the detailed description, with each claim standing on its own as a separate embodiment.

Metadata:
Filing Date: 20230309
Publication Date: 20240917
Grant Date: 20240917
Priority Date: 20170619
Inventors: SIROTKIN, ALEXANDER
Yu, Yifan
HUANG, MIN
HAN, Jaemin
YANG, FENG
Assignee: APPLE INC
CPC Classifications: [{"code": "H04W92/20", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W80/02", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W88/085", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W80/02", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W92/20", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W76/12", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04W76/12", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04W92/20", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W80/02", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W76/12", "inventive": true, "first": true, "tree": "[]"}]
Family ID: 64737822