PATENT DOCUMENT

Publication Number: US-11122505-B2
Application Number: US-201615767562-A
Country: US
Kind Code: B2

Title: Downlink data handling for idle mode UE when the SGW is split into control plane node and user plane node

Abstract:
An apparatus for use in a serving gateway user plane (SGW-U) of an evolved packet core (EPC) of a wireless communication network is disclosed. The apparatus comprises one or more processors configured to process a downlink (DL) data signal comprising a DL data packet for a user equipment (UE) in the network, buffer the DL data packet in the DL data signal and identify a serving gateway control plane (SGW-C) associated with the SGW-U that serves the UE, when the UE is in idle mode. The one or more processors is further configured to provide an SGW-U DL data notification message to the SGW-C, generated selectively based on a priority of the received DL data signal, in order to inform the SGW-C about the availability of DL data for the UE.

Claims:
What is claimed is: 
     
       1. An apparatus for a serving gateway user plane (SGW-U) comprising a user plane node associated with a serving gateway (SGW) of an evolved packet core (EPC) of a wireless communication network, the apparatus comprising:
 one or more processors configured to: 
 process a received downlink (DL) data signal comprising a DL data packet for a user equipment (UE) in the wireless communication network; 
 buffer the DL data packet; 
 identify a serving gateway control plane (SGW-C) associated with the SGW-U that serves the UE, wherein the SGW-C comprises a control plane node associated with the SGW; 
 provide an SGW-U DL data notification message to the SGW-C, in order to inform the SGW-C about an availability of the DL data packet for the UE; 
 process an SGW-C DL data notification acknowledge message received from the SGW-C, in response to the SGW-U DL data notification message provided to the SGW-C, wherein the SGW-C DL data notification acknowledge message comprises a DL buffering requested indication comprising a DL buffering duration time; and 
 introduce a delay corresponding to the DL buffering duration time prior to providing a subsequent SGW-U DL data notification message to the SGW-C, when subsequent data packets are received at the SGW-U before an expiration of the DL buffering duration time. 
 
     
     
       2. The apparatus of  claim 1 , wherein the SGW-U DL data notification message to the SGW-C comprises information on one or more of allocation and retention priority (ARP), evolved packet system (EPS) bearer ID and paging priority indication associated with the DL data packet, and wherein the SGW-U DL data notification message is configured to establish evolved packet system (EPS) bearers of the UE in the wireless communication network. 
     
     
       3. The apparatus of  claim 1 , wherein the one or more processors are further configured to drop the DL data packet and not generate the SGW-U DL data notification message to the SGW-C, when the DL data packet is received on a low priority bearer, based on a request from the SGW-C or a mobility management entity (MME) associated therewith. 
     
     
       4. The apparatus of  claim 1 , wherein the one or more processors are configured to introduce a predetermined delay prior to providing the SGW-U DL data notification message to the SGW-C, based on a request to delay sending the SGW-U DL data notification message to the SGW-C, received from the SGW-C associated therewith. 
     
     
       5. The apparatus of  claim 1 , wherein the DL buffering duration time indicates a time required to establish radio bearers of the UE, in order to send the DL data to the UE. 
     
     
       6. The apparatus of  claim 1 , wherein the SGW-C DL data notification acknowledge message comprises an indication that the SGW-U DL data notification message provided to the SGW-C is temporarily rejected by a mobility management entity (MME) or a service GPRS support node (SGSN) associated therewith. 
     
     
       7. The apparatus of  claim 6 , wherein the one or more processors are further configured to start a locally configured guard timer having a predetermined delay associated therewith, and buffer subsequent DL data packets, until a modify bearer request message is received from a second MME or a second SGSN associated therewith, or the locally configured guard timer is expired, when the SGW-C DL data notification acknowledge message comprises the indication that the SGW-U DL data notification message is temporarily rejected. 
     
     
       8. The apparatus of  claim 7 , wherein, upon receiving the modify bearer request message, the one or more processors are further configured to provide the SGW-U DL data notification message again to the SGW-C, for subsequent transmission to the second MME or the second SGSN from which the modify bearer request message is received. 
     
     
       9. The apparatus of  claim 7 , wherein the one or more processors are further configured to release the buffered DL data packets, if the locally configured guard timer is expired or a delete session request message is received from an MME or an SGSN associated therewith, before receiving the modify bearer request message. 
     
     
       10. An apparatus for a serving gateway control plane (SGW-C) comprising a control plane node associated with a serving gateway (SGW) of a wireless communication network, the apparatus comprising:
 one or more processors configured to: 
 process a serving gateway user plane (SGW-U) downlink (DL) data notification message received from a serving gateway user plane (SGW-U) comprising a user plane node associated with the SGW, wherein the SGW-U DL data notification message indicates an availability of a DL data for a user equipment (UE) served by the SGW-C; 
 provide a first SGW-C DL data notification message, generated based on the SGW-U DL data notification message, to a mobility management entity (MME) associated with the UE; 
 process an MME DL data notification acknowledge (ACK) message received from the MME, in response to providing the first SGW-C DL data notification message to the MME, wherein the MME DL data notification ACK message comprises a DL buffering duration time; and 
 provide an SGW-C DL data notification acknowledge message to the SGW-U, in response to processing the MME DL data notification ACK message from the MME, wherein the SGW-C DL data notification acknowledge message comprises a status information associated with the SGW-U DL data notification message and the DL buffering duration time, wherein the DL buffering duration time causes the SGW-U to introduce a delay corresponding to the DL buffering duration time prior to providing a subsequent SGW-U DL data notification message to the SGW-C, when subsequent data packets are received at the SGW-U before an expiration of the DL buffering duration time. 
 
     
     
       11. The apparatus of  claim 10 , wherein the first SGW-C DL data notification message provides to the MME, an indication of the availability of the DL data for the UE. 
     
     
       12. The apparatus of  claim 11 , wherein the first SGW-C DL data notification message to the SGW-C comprises information on one or more of an allocation and retention priority (ARP), evolved packet system (EPS) bearer ID and paging priority indication associated with the DL data, and wherein the first SGW-C DL data notification message is configured to establish evolved packet system (EPS) bearers of the UE in the wireless communication network. 
     
     
       13. The apparatus of  claim 10 , wherein the one or more processors are further configured to provide a second SGW-C DL data notification message, generated based on the SGW-U DL data notification message, to a service GPRS support node (SGSN) associated with the UE, in order to transfer the DL data to the UE, prior to providing the SGW-C DL data notification acknowledge message to the SGW-U, wherein the second SGW-C DL data notification message comprises an indication of the availability of the DL data for the UE. 
     
     
       14. The apparatus of  claim 13 , wherein the one or more processors are further configured to:
 process an SGSN DL data notification acknowledge message received from the SGSN, in response to the second SGW-C DL data notification message from the SGW-C, prior to providing the SGW-C DL data notification acknowledge message to the SGW-U, 
 wherein the SGSN DL data notification acknowledge message comprises a status information associated with the second SGW-C DL data notification message, and 
 wherein the SGW-C DL data notification acknowledge message to the SGW-U is generated based on the SGSN DL data notification acknowledge message. 
 
     
     
       15. A non-transitory computer-readable medium storing executable instructions that, in response to execution, cause one or more processors of a mobility management entity (MME) of a wireless communication network, to perform operations comprising:
 processing a first serving gateway control plane (SGW-C) downlink (DL) data notification message received from a serving gateway control plane (SGW-C) comprising a control plane node associated with a serving gateway (SGW), wherein the first SGW-C DL data notification message indicates an availability of a DL data for a user equipment (UE) served by the MME; and 
 providing an MME DL data notification acknowledge message to the SGW-C, in response to the first SGW-C DL data notification message, wherein the MME DL data notification acknowledge message comprises a status information associated with the first SGW-C DL data notification message and a DL buffering requested indication comprising a DL buffering duration time, wherein the MME DL data notification acknowledge message causes the SGW-C to provide an SGW-C DL data notification acknowledge message comprising the DLexper buffering duration time to a serving gateway user plane (SGW-U) comprising a user plane node associated with the SGW to cause the SGW-U to introduce a delay corresponding to the DL buffering duration time prior to providing a subsequent SGW-U DL data notification message to the SGW-C, when subsequent data packets are received at the SGW-U before an expiration of the DL buffering duration time. 
 
     
     
       16. The non-transitory computer-readable medium of  claim 15 , wherein the first SGW-C DL data notification message comprises information on one or more of an allocation and retention priority (ARP), evolved packet system (EPS) bearer ID and paging priority indication associated with the DL data, and wherein the MME is configured to establish evolved packet system (EPS) bearers of the UE in the wireless communication network, based on the first SGW-C DL data notification message. 
     
     
       17. The non-transitory computer-readable medium of  claim 15 , wherein the operations further comprise deriving the DL buffering duration time required to establish radio bearers of the UE, when the UE is in a power saving mode. 
     
     
       18. The non-transitory computer-readable medium of  claim 15 , wherein the operations further comprise rejecting the first SGW-C DL data notification message from the SGW-C, when a tracking area update (TAU) procedure with the MME changes or a routing area update (RAU) procedure of the MME is in progress, and wherein the MME DL data notification acknowledge message comprises an indication that the first SGW-C DL data notification message has been temporarily rejected. 
     
     
       19. The apparatus of  claim 10 , wherein the one or more processors are further configured to provide a request to delay sending the SGW-U DL data notification message to the SGW-C, to the SGW-U.

Description:
REFERENCE TO RELATED APPLICATIONS 
     This application is a National Phase entry application of International Patent Application No. PCT/US2016/049380 filed Aug. 30, 2016, which claims priority to International Patent Application PCT/CN2015/094005 filed on Nov. 6, 2015, entitled “DOWNLINK DATA HANDLING FOR IDLE MODE UE WHEN THE SGW IS SPLIT INTO CONTROL PLANE NODE AND USER PLANE NODE” in the name of Changhong Shan and is hereby incorporated by reference in its entirety. 
     FIELD 
     The present disclosure relates to the field of wireless communications, and more specifically to a method and an apparatus for handling downlink (DL) data for an idle mode user equipment (UE) in wireless communication networks. 
     BACKGROUND 
     In recent years, demand for access to fast mobile wireless data for mobile electronic devices has fueled the development of the 3rd Generation Partnership Project (3GPP) long term evolution (LTE) communication system (hereinafter “LTE system”). In LTE systems, serving gateway (SGW) is the gateway which terminates the interface towards E-UTARN. SGW is responsible for handovers with neighboring eNodeBs, also for data transfer in terms of all packets across user plane. For idle state UEs, the SGW terminates the downlink (DL) data path and triggers paging when downlink data arrives for the UE. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Some examples of circuits, apparatuses and/or methods will be described in the following by way of example only. In this context, reference will be made to the accompanying Figures. 
         FIG. 1  illustrates an architecture of a wireless communication network, according to one embodiment of the disclosure. 
         FIG. 2  illustrates a signal flow that enables a wireless communication network to handle downlink (DL) data for a UE in idle mode in the network, according to one embodiment of the disclosure. 
         FIG. 3  illustrates a block diagram of an apparatus for use in a serving gateway user plane (SGW-U) of a wireless communication network, that facilitates handling downlink (DL) data for an idle mode user equipment (UE) in the network, according to the various embodiments described herein. 
         FIG. 4  illustrates a block diagram of an apparatus for use in a serving gateway control plane (SGW-C) of a wireless communication network, that facilitates handling downlink (DL) data for an idle mode user equipment (UE) in the network, according to the various embodiments described herein. 
         FIG. 5  illustrates a block diagram of an apparatus for use in a mobility management entity (MME) of a wireless communication network, that facilitates handling downlink (DL) data for an idle mode user equipment (UE) in the network, according to the various embodiments described herein. 
         FIG. 6  illustrates a flowchart of a method for a serving gateway user plane (SGW-U) of a wireless communication network that facilitates handling downlink (DL) for an idle mode UE in the network, according to one embodiment of the disclosure. 
         FIG. 7  illustrates a flowchart of a method for a serving gateway control plane (SGW-C) of a wireless communication network that facilitates handling downlink (DL) for an idle mode UE in the network, according to one embodiment of the disclosure. 
         FIG. 8  illustrates a flowchart of a method for a mobility management entity (MME) of a wireless communication network that facilitates handling downlink (DL) for an idle mode UE in the network, according to one embodiment of the disclosure. 
         FIG. 9  illustrates, for one embodiment, example components of an electronic device. 
     
    
    
     DETAILED DESCRIPTION 
     In one embodiment of the disclosure, an apparatus for use in a serving gateway user plane (SGW-U) of an evolved packet core (EPC) of a wireless communication network is disclosed. The apparatus comprises a processing circuit configured to process a downlink (DL) data signal comprising a DL data packet for a user equipment (UE) in the network; and identify a serving gateway control plane (SGW-C) associated with the SGW-U that serves the UE, when the UE is in idle mode. The apparatus further comprises a memory circuit configured to buffer the DL data packet in the DL data signal, when the UE is in the idle mode. 
     In one embodiment of the disclosure, an apparatus for use in a serving gateway control plane (SGW-C) of a wireless communication network is disclosed. The apparatus comprises a processing circuit configured to process an SGW-U downlink (DL) data notification message received from a serving gateway user plane (SGW-U) associated therewith, wherein the SGW-U DL data notification message indicates an availability of a DL data for an idle mode user equipment (UE) served by the SGW-C. The processing circuit is further configured to provide a SGW-C DL data notification acknowledge message to the SGW-U, in response to the SGW-U DL data notification message, wherein the SGW-C DL data notification acknowledge message comprises a status information associated with the SGW-U DL data notification message. 
     In one embodiment of the disclosure, an apparatus for use in a mobility management entity (MME) of a wireless communication network is disclosed. The apparatus comprises a processing circuit configured to process a first SGW-C downlink (DL) data notification message received from a serving gateway control plane (SGW-C) associated therewith, wherein the first SGW-C DL data notification message indicates an availability of a DL data for an idle mode user equipment (UE) served by the MME. The processing circuit is further configured to provide an MME DL data notification acknowledge message to the SGW-C, in response to the first SGW-C DL data notification message, wherein the MME DL data notification acknowledge message comprises a status information associated with the first SGW-C DL data notification message. 
     The present disclosure will now be described with reference to the attached drawing figures, wherein like reference numerals are used to refer to like elements throughout, and wherein the illustrated structures and devices are not necessarily drawn to scale. As utilized herein, terms “component,” “system,” “interface,” and the like are intended to refer to a computer-related entity, hardware, software (e.g., in execution), and/or firmware. For example, a component can be a processor (e.g., a microprocessor, a controller, or other processing device), a process running on a processor, a controller, an object, an executable, a program, a storage device, a computer, a tablet PC and/or a user equipment (e.g., mobile phone, etc.) with a processing device. By way of illustration, an application running on a server and the server can also be a component. One or more components can reside within a process, and a component can be localized on one computer and/or distributed between two or more computers. A set of elements or a set of other components can be described herein, in which the term “set” can be interpreted as “one or more.” 
     Further, these components can execute from various computer readable storage media having various data structures stored thereon such as with a module, for example. The components can communicate via local and/or remote processes such as in accordance with a signal having one or more data packets (e.g., data from one component interacting with another component in a local system, distributed system, and/or across a network, such as, the Internet, a local area network, a wide area network, or similar network with other systems via the signal). 
     As another example, a component can be an apparatus with specific functionality provided by mechanical parts operated by electric or electronic circuitry, in which the electric or electronic circuitry can be operated by a software application or a firmware application executed by one or more processors. The one or more processors can be internal or external to the apparatus and can execute at least a part of the software or firmware application. As yet another example, a component can be an apparatus that provides specific functionality through electronic components without mechanical parts; the electronic components can include one or more processors therein to execute software and/or firmware that confer(s), at least in part, the functionality of the electronic components. 
     Use of the word exemplary is intended to present concepts in a concrete fashion. As used in this application, the term “or” is intended to mean an inclusive “or” rather than an exclusive “or”. That is, unless specified otherwise, or clear from context, “X employs A or B” is intended to mean any of the natural inclusive permutations. That is, if X employs A; X employs B; or X employs both A and B, then “X employs A or B” is satisfied under any of the foregoing instances. In addition, the articles “a” and “an” as used in this application and the appended claims should generally be construed to mean “one or more” unless specified otherwise or clear from context to be directed to a singular form. Furthermore, to the extent that the terms “including”, “includes”, “having”, “has”, “with”, or variants thereof are used in either the detailed description and the claims, such terms are intended to be inclusive in a manner similar to the term “comprising.” 
     As indicated above, in LTE systems, the serving gateway (SGW) terminates the downlink (DL) data path and triggers paging when downlink data arrives for a UE in idle state. In current SGW implementations, the control plane and the user plane are tightly coupled together. When SGW receives a data packet for a UE that is not user plane connected (i.e., in idle mode), dedicated bearers for the UE has to be established, in order to forward the data packet to the UE. For UEs in idle mode, the SGW handles DL data as defined in section 5.3.4.3 of technical specification (TS) 23.401. However, in some embodiments, the SGW may be split into a user plane node, SGW-U and a control plane node, SGW-C, respectively. 
     Various embodiments described herein facilitates handling of downlink data at SGW-U and SGW-C when the downlink data arrives at SGW-U for a UE in idle mode. In one embodiment, an apparatus and a method that facilitates handling of DL data at the SGW-U is disclosed. In another embodiment, an apparatus and a method that facilitates handling of DL data at the SGW-C is disclosed. In yet another embodiment, an apparatus and a method that facilitates handling of DL data at a mobility management entity (MME) is disclosed. 
       FIG. 1  illustrates an architecture of a wireless communication network  100 , according to one embodiment of the disclosure. In some embodiments, the wireless communication network  100  facilitates handling control and data traffic to and from user equipments (UEs) in the network. The wireless communication network  100  comprises a UE  102 , an eNodeB  104  and a mobility managing node, for example, mobility management entity (MME)  106 . The network  100  further comprises a serving gateway user plane (SGW-U)  108   a , a serving gateway control plane (SGW-C)  108   b , a packet data network gateway user plane (PGW-U)  110   a  and a packet data network gateway control plane (PGW-C)  110   b . Furthermore, the network  100  comprises a home subscriber server (HSS)  112 , a traffic detection function user plane (TDF-U)  114   a  and a traffic detection function control plane (TDF-C)  114   b . In some embodiments, the network  100  further comprises an additional mobility managing node, for example, serving GPRS support node (SGSN) (not shown) associated with the network. 
     In some embodiments, the MME  106 , the SGW-U  108   a , the SGW-C  108   b , the PGW-U  110   a , the PGW-C  110   b  and HSS  112  forms an evolved packet core (EPC) and is referred to as a core network. In some embodiments, the UE  102  is coupled to the eNodeB  104  over a Uu interface  103  and the eNodeB  104  is coupled to the MME  106  over a S1-MME interface  105 . Further, the network  100  comprises a S1-U interface  107  between the eNodeB  104  and the SGW-U  108   a , an S11 interface between the MME  106  and the SGW-C  108   b , and an SGWi interface  109  between the SGW-U and SGW-C. In addition, the network  100  comprises interfaces S5/8-C  113  and S5/8-C  113  between SGW-C  108   b  and PGW-C  110   b , and SGW-U  108   a  and PGW-U  110   a , respectively. Furthermore, the network  100  comprises a PGWi interface  117  between the PGW-U  110   a  and the PGW-C  110   b . In some embodiments, the SGW-C  108   b  and PGW-C  110   b  may be collocated in the cloud. In such embodiments, the S5/8-C interface  113  may not be included, and signaling interaction between SGW-C  108   b  and PGW-C  110   b  may not be required. Further, in some embodiments, SGW-U  108   a  and PGW-U  110   a  also may be collocated, thus S5/8-U  115  may not be included, and SGWi  109  and PGWi  117  may be combined into one interface. In some embodiments, the SGSN (not shown) is coupled to the MME via an S3 interface (not shown) and the SGSN is coupled to the SGW-C via an S4 interface (not shown). 
     In some embodiments, when the SGW-U  108   a  receives data packets (i.e., downlink data) for a UE (e.g., UE  102 ) in the network that is not user plane connected (i.e., UE in idle mode), dedicated bearers have to be established for the UE in order to forward the downlink (DL) data to the UE. In such embodiments, the SGW-U  108   a  may buffer the data packets and send the data packets to the UE only when the dedicated bearers for the UE are established in the network. The signal flow that enables the SGW-U  108   a  to handle the DL data is described in greater detail below. 
       FIG. 2  illustrates a signal flow that enables a wireless communication network  200  to handle downlink (DL) data for a UE in idle mode in the network, according to one embodiment of the disclosure. In this embodiment, the serving gateway (SGW) of the network  200  is split into SGW-U and SGW-C. In some embodiments, the wireless communication network  200  in  FIG. 2  is similar to the wireless communication network  100  in  FIG. 1 . The wireless communication network  200  comprises a UE  202 , an eNodeB  204 , and MME  206  and/or a SGSN  208 . Further, the network  200  comprises a SGW-C  210 , a SGW-U  212 , a PGW-C  214  and a PGW-U  216 . In some embodiments, the signal flow described below comprises a network triggered service request procedure. 
     The SGW-U  212  initiates the DL data transfer to the UE  202 , when the SGW-U  212  has DL data available for the UE  212 . In some embodiments, the DL data is received at the SGW-U via a DL data signal  218  comprising a DL data packet from the PGW-U  216  in the network  200 . In some embodiments, if the UE  212  is in idle mode or is not user plane connected (i.e., the SGW-U context data indicates no downlink user plane tunnel endpoint identifier (DL-TEID)), dedicated bearers have to be established for the UE  212 , in order to forward the data packet to the UE  212 . In such embodiments, the SGW-U  212  is configured to buffer the data packets, prior to forwarding the data packets to the UE  202 . Further, the SGW-U  212  is configured to identify a SGW-C, for example, the SGW-C  210  associated with the SGW-U  212  that serves the UE  202 , in order to establish dedicated bearers for the UE  202  in the network. 
     Upon identifying the SGW-C  210  that serves the UE  202 , the SGW-U  212  is configured to selectively generate a SGW-U DL data notification message  220  and provide the generated SGW-U DL data notification message  220  to the SGW-C  210 , based on a priority of the received DL data packet. For example, in some embodiments, if the MME  206  and the SGW-C  210  have requested the SGW-U  212  to throttle downlink low priority traffic (for example, during an initial attach procedure), and if the DL data packet is received on a low priority bearer to be throttled, the SGW-U  212  may drop the downlink data packet. In such embodiments, the SGW-U  212  may not generate the SGW-U DL data notification message  220 . In some embodiments, the SGW-U DL data notification message  220  indicates the availability of DL data for the UE  202 . In some embodiments, the SGW-U DL data notification message  220  comprises information on allocation and retention priority (ARP) and EPS bearer ID associated with a bearer on which the DL data packet is received. When supporting paging policy differentiation, the SGW-U  212  may indicate in the SGW-U DL data notification message  220 , a paging policy indication that is related to the downlink data that triggered the SGW-U DL data notification message  220 , as discussed in clause 4.9 of technical specification (TS) 23.401. 
     In some embodiments, if the MME  206  and the SGW-C  210  have requested the SGW-U  212  to delay sending the downlink data notification (as discussed in 3GPP TS 23.401, sec. 5.3.4.2 on “Handling of abnormal conditions in UE triggered Service Request”), the SGW-U  212  may buffer the downlink data and wait until a timer expires before sending the SGW-U DL data notification message  220 . In some embodiments, the delay introduced by the timer corresponds to a delay provided by the MME  206  and the SGW-C  210 . If however, the DL-TEID and eNodeB address for UE  202  is received at the SGW-U  212  before the expiry of the timer, the timer may be cancelled and the network triggered service request procedure may be completed by sending the DL data from the SGW-C  212  to the UE  202 . Further, if the SGW-U  212  receives additional DL data packets for the UE  202 , before the expiry of the timer, the SGW-U does not restart the timer. 
     Upon receiving the SGW-U DL data notification message  220 , the SGW-C  210  is configured to generate a first SGW-C DL data notification message  222  and provide the generated first SGW-C DL data notification message  222  to an MME, for example, the MME  206  serving the UE  202 . In some embodiments, the SGW-C  210  is further configured to generate a second SGW-C DL data notification message  226  and provide the generated second SGW-C DL data notification message  226  to the SGSN  208 . In some embodiments, the first SGW-C DL data notification message  222  and the second SGW-C DL data notification message  226  generated at the SGW-C  210  indicates the availability of DL data for the UE  202 . In some embodiments, the first SGW-C DL data notification message  222  and the second SGW-C DL data notification message  226  comprises information on allocation and retention priority (ARP) and EPS bearer ID associated with a bearer on which the DL data packet is received. When supporting paging policy differentiation, the SGW-C  210  may indicate in the first SGW-C DL data notification message  222  and in the second SGW-C DL data notification message  226 , a paging policy indication that is related to the downlink data that triggered first SGW-C DL data notification message  222  and the second SGW-C DL data notification message  226 , respectively, as discussed in clause 4.9 of TS 23.401. 
     The MME  206  is configured to generate an MME DL data notification acknowledge (Ack) message  224 , in response to receiving the first SGW-C DL data notification message  222  from the SGW-C  210  and provide the generated MME DL data notification acknowledge (Ack) message  224  to the SGW-C  210 . In some embodiments, the MME DL data notification ack message  224  comprises a status information associated with the first SGW-C DL data notification message  222 . Upon receiving the MME DL data notification ack message  224 , the SGW-C  210  is configured to generate an SGW-C DL data notification ack message  230 , based on the received MME DL data notification ack message  224 . In some embodiments, the SGW-C DL data notification ack message  230  comprises a status information associated with the SGW-U DL data notification message  220 . 
     The SGSN  208  is configured to generate an SGSN DL data notification acknowledge (Ack) message  228 , in response to receiving the second SGW-C DL data notification message  226  from the SGW-C  210  and provide the generated SGSN DL data notification acknowledge (Ack) message  228  to the SGW-C  210 . In some embodiments, the SGSN DL data notification ack message  228  comprises a status information associated with the second SGW-C DL data notification message  226 . Upon receiving the SGSN DL data notification ack message  224 , the SGW-C  210  is configured to generate the SGW-C DL data notification ack message  230 , based on the received SGSN DL data notification ack message  228 . In some embodiments, the SGW-C DL data notification ack message  230  comprises a status information associated with the SGW-U DL data notification message  220 . 
     In some embodiments, if the MME  206  and the SGSN  208  identifies that the UE  202  is in a power saving state (i.e., a power saving mode) and cannot be reached by paging at the moment, the MME  206  and SGSN  208  is configured to invoke extended buffering, depending on operator configuration. In such embodiments, the MME  206 /SGSN  208  is configured to derive a DL buffering duration time based on an expected time to establish radio bearers to the UE  202 . The MME  206 /SGSN  208  stores a value for the DL buffering duration time in the context for the UE. The DL buffering duration time is used for UEs, for example, UE  202 , using power saving state and indicates that there are buffered data in the SGW-U  212  and that the user plane setup procedure is needed when the UE  202  makes signaling with the network. When the DL buffering duration time has expired, the MME  206 /SGSN  208  considers no DL data to be buffered and no indications of buffered DL data are sent during context transfers at TAU procedures. 
     In such embodiments, the MME DL data notification ack message  224  and the SGSN DL data notification ack message  228  to the SGW-C  210  comprises a DL buffering requested indication comprising the derived DL buffering duration time as indicated above. Further, the SGW-C DL data notification ack message  230  comprises the DL buffering requested indication comprising the derived DL buffering duration time. Upon receiving the DL buffering requested indication in the SGW-C DL data notification ack message  230 , the SGW-U  212  is configured to store the received DL buffering duration time and not send any additional DL data notification messages, if subsequent downlink data packets are received at the SGW-U  212  before the DL buffering duration time has expired for the UE  202 . 
     In some embodiments, if the SGW-U  212 , while waiting for the user plane to be established, is triggered to send a second, different SGW-U DL data notification message for a bearer with higher priority (i.e. ARP priority level) than the first SGW-U DL data notification message (e.g., the SGW-U DL data notification message  220 ) was sent for, the SGW-U  212  sends a new SGW-U DL data notification message indicating the higher priority to the SGW-C  210 . If the SGW-U  212  receives additional downlink data packets for a bearer with same or lower priority than the first DL data notification message (e.g., the SGW-U DL data notification message  220 ) was sent for or if the SGW-U  212  has sent the second DL data notification message indicating the higher priority and receives additional downlink data packets for the UE  202 , the SGW-U  212  buffers these downlink data packets and does not send a new SGW-U DL data notification message. 
     In some embodiments, if a tracking area update (TAU) procedure with the MME  206  change or a routing area update (RAU) procedure is in progress when the MME  206  receives a first SGW-C DL data notification message (e.g., the first SGW-C DL data notification message  222 ) from the SGW-C  210 , the MME  206  may reject the first SGW-C DL data notification message with an indication that the first SGW-C DL data notification message has been temporarily rejected. In such embodiments, the MME DL data notification ack message  224  to the SGW-C  210  comprises an indication that the first SGW-C DL data notification message  222  has been temporarily rejected. The rejection of the first SGW-C DL data notification message  222 , in some embodiments, corresponds to a rejection of the SGW-U DL data notification message  220  from the SGW-U  212 . Therefore, in such embodiments, the SGW-C DL data notification ack message  230  to the SGW-U  212  comprises an indication that the SGW-U DL data notification message  220  has been temporarily rejected. 
     Similarly, if the routing area update (RAU) procedure with SGSN  208  change or the TAU procedure is in progress when the SGSN (e.g., the SGSN  208 ) receives a DL data notification message (e.g., the second SGW-C DL data notification message  226 ), the SGSN (i.e., the SGSN  208 ) may reject the second SGW-C DL data notification message with an indication that the second SGW-C DL data notification message has been temporarily rejected. In such embodiments, the SGSN DL data notification ack message  228  to the SGW-C  210  comprises an indication that the second SGW-C DL data notification message  226  has been temporarily rejected. The rejection of the second SGW-C DL data notification message  226 , in some embodiments, corresponds to a rejection of the SGW-U DL data notification message  220  from the SGW-U  212 . Therefore, in such embodiments, the SGW-C DL data notification ack message  230  to the SGW-U  212  comprises an indication that the SGW-U DL data notification message  220  has been temporarily rejected. 
     Upon receiving the indication that the SGW-U DL data notification message  220  has been temporarily rejected, in some embodiments, the SGW-U  212  may start a locally configured guard timer and buffers all downlink user packets received for the UE  202  and waits for a modify bearer request message to come from an MME or SGSN associated therewith. Upon reception of a modify bearer request message, the SGW-U  212  may resend the SGW-U DL data notification message  220  to the SGW-C  210 , and the SGW-C  210  may re-send the first SGW-C DL data notification message  222  or the second SGW-C DL data notification message  226 , respectively, only to the new MME or the new SGSN from which the SGW-C  210  received the modify bearer request message. In the embodiments where the SGW-U  212  or the SGW-C  210  does not receive a modify bearer request message from an MME or a SGSN, the SGW-U  212  releases the buffered downlink user packets at an expiry of the guard timer or receiving a delete session request message from the MME or the SGSN. 
       FIG. 3  illustrates a block diagram of an apparatus  300  for use in a serving gateway user plane (SGW-U) of a wireless communication network, that facilitates handling downlink (DL) data for an idle mode user equipment (UE) in the network, according to the various embodiments described herein. The apparatus  300  is explained herein with reference to the SGW-U  212  in  FIG. 2 . The apparatus  300  includes a processing circuitry  310  coupled with an interface circuitry  320 . In some embodiments, the apparatus  300  further comprises a memory circuit  330  configured to store instructions and data associated with the SGW-U. In some embodiments, the processing circuitry  310  can comprise one or more processors. In some embodiments, various functions of the processing circuity  310  are performed using different processors. However, in other embodiments, various functions of the processing circuitry  310  can be performed in a single processor. In some embodiments, the memory circuit  330  can be a single memory or a plurality of memories. In some embodiments, the plurality of memories can be in a single location, e.g., a semiconductor chip, or in other embodiments, the plurality of memories can be in different locations. As used herein, the term “circuitry” or “circuit” 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. 
     The interface circuitry  320  may be configured to communicate with other network entities over various interfaces using appropriate networking communication protocols. The interface circuitry  320  may be capable of communicating over any number of wired or wireless communication interfaces. In some embodiments, the interface circuitry  320  may communicate over Ethernet or other computer networking technologies using a variety of physical media interfaces such as, but not limited to, coaxial, twisted-pair compare, and fiber-optics media interfaces. The processing circuitry  310  may be configured to provide higher-layer operations that include generating and processing signals transmitted and received by the interface circuitry  320 . 
     In some embodiments, the apparatus  300  can be included within the SGW-U  212  in  FIG. 2 . When downlink (DL) data is available for UE in the network, the apparatus  300  within the SGW-U  212  receives the DL data from a PDN gateway (e.g., the PGW-U  216 ) associated therewith. In such embodiments, the processing circuitry  310  within the apparatus  300  is configured to receive a DL data signal (e.g., the DL data signal  218 ) comprising a DL data packet via the interface circuitry  320 . The processing circuitry  310  is further configured to process the DL data signal and identify the UE (e.g., the UE  202 ) to which the DL data is to be send. If the UE (e.g., the UE  202 ) is in idle mode, the processing circuitry  310  is configured to buffer the DL data packet and store the DL data packet in the memory circuit  330 . 
     Further, the processing circuit  310  is configured to identify an SGW-C (e.g., the SGW-C  210 ) serving the UE (e.g., the UE  202 ). In addition, the processing circuitry  310  is configured to provide an SGW-U DL data notification message (e.g., the SGW-U DL data notification message  220 ), selectively generated based on a priority of the received DL data signal at the processing circuit  310 , to the SGW-C (e.g., the SGW-C  210 ). For example, in some embodiments, the processing circuitry  310  is configured to drop the DL data packet and not provide the SGW-U DL data notification message to the SGW-C, when the DL data packet is received on a low priority bearer, based on a request from the SGW-C (e.g., the SGW-C  210 ) or a mobility management entity (MME) (e.g., MME  206 ) associated therewith. In some embodiments, the generated SGW-U DL data notification message is provided to the SGW-C, via the interface circuitry  320 , in order to inform the SGW-C about the availability of DL data for the UE. 
     In some embodiments, the processing circuitry  301  is further configured to introduce a predetermined delay prior to providing the SGW-U DL data notification message to the SGW-C, based on a request from the SGW-C (e.g., the SGW-C  210 ) or a mobility management entity (MME) (e.g., MME  206 ) associated therewith to delay sending the SGW-U DL data notification message to the SGW-C. In some embodiments, the predetermined delay is provided by the MME or the SGW-C and is stored in the memory circuit  330 . 
     In some embodiments, the processing circuitry  320  is further configured to process an SGW-C DL data notification ack message (e.g., the SGW-C DL data notification ack message  230 ) received from the SGW-C (e.g., the SGW-C  210 ), via the interface circuitry  320 , in response to sending the SGW-U DL data notification message to the SGW-C. In some embodiments, the SGW-C DL data notification acknowledge message received from the SGW-C comprises a status information associated with the SGW-U DL data notification message. In some embodiments, the SGW-C DL data notification acknowledge message (e.g., the SGW-C DL data notification ack message  230 ) received from the SGW-C comprises a DL buffering requested indication comprising a DL buffering duration time that indicates a time required to establish radio bearers of the UE, in order to send the DL data to the UE. In some embodiments, the DL buffering duration time is stored in the memory circuit  330 . In such embodiments, the processing circuitry  310  is configured to introduce a delay corresponding to the DL buffering duration time prior to providing a subsequent SGW-U DL data notification message to the SGW-C, when subsequent data packets are received at the SGW-U before the expiration of the DL buffering duration time. 
     In some embodiments, the SGW-C DL data notification acknowledge message (e.g., the SGW-C DL data notification ack message  230 ) received from the SGW-C at the processing circuit  310  comprises an indication that the SGW-U DL data notification message (e.g., the SGW-U DL data notification message  220 ) provided to the SGW-C is temporarily rejected by a mobility management entity MME or a service GPRS support node (SGSN) associated therewith. In such embodiments, the processing circuitry  310  is configured to start a locally configured guard timer having a predetermined delay associated therewith, and buffer subsequent DL data packets in the memory circuit  330 , until a modify bearer request message is received from an MME or an SGSN associated therewith, or the guard timer is expired. The processing circuitry  310 , upon receiving the modify bearer request message, is configured to provide the SGW-U DL data notification message again to the SGW-C, for subsequent transmission to the MME or the SGSN from which the modify bearer request message is received. In some embodiments, the processing circuitry  310  is further is configured to release the buffered DL data packets, if the guard timer is expired or a delete session request message is received from an MME or a SGSN associated therewith, before receiving the modify bearer request message. 
       FIG. 4  illustrates a block diagram of an apparatus  400  for use in a serving gateway control plane (SGW-C) of a wireless communication network, that facilitates handling downlink (DL) data for an idle mode user equipment (UE) in the network, according to the various embodiments described herein. The apparatus  400  is explained herein with reference to the SGW-C  210  in  FIG. 2 . The apparatus  400  includes a processing circuitry  410  coupled with an interface circuitry  420 . In some embodiments, the apparatus  400  further comprises a memory circuit  430  configured to store instructions and data associated with the SGW-C. In some embodiments, the processing circuitry  410  can comprise one or more processors. In some embodiments, various functions of the processing circuity  410  are performed using different processors. However, in other embodiments, various functions of the processing circuitry  410  can be performed in a single processor. In some embodiments, the memory circuit  430  can be a single memory or a plurality of memories. In some embodiments, the plurality of memories can be in a single location, e.g., a semiconductor chip, or in other embodiments, the plurality of memories can be in different locations. As used herein, the term “circuitry” or “circuit” 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. 
     The interface circuitry  420  may be configured to communicate with other network entities over various interfaces using appropriate networking communication protocols. The interface circuitry  420  may be capable of communicating over any number of wired or wireless communication interfaces. In some embodiments, the interface circuitry  420  may communicate over Ethernet or other computer networking technologies using a variety of physical media interfaces such as, but not limited to, coaxial, twisted-pair compare, and fiber-optics media interfaces. The processing circuitry  410  may be configured to provide higher-layer operations that include generating and processing signals transmitted and received by the interface circuitry  420 . 
     In some embodiments, the apparatus  400  can be included within the SGW-C  210  in  FIG. 2 . When downlink (DL) data is available for a UE in the network, the apparatus  400  receives the DL data from a SGW-U (e.g., the SGW-U  212 ) associated therewith. In such embodiments, the processing circuitry  410  is configured to receive an SGW-U DL data notification message (e.g., the SGW-U DL data notification message  220 ) via the interface circuitry  420 , from an SGW-U (e.g., the SGW-U  212 ) associated therewith. In some embodiments, the SGW-U DL data notification message indicates an availability of a DL data for a user equipment (UE) served by the SGW-C. Upon receiving the SGW-U DL data notification message, the processing circuitry  410  is configured to generate a first SGW-C DL data notification message (e.g., the first SGW-C DL data notification message  222 ) for subsequent transmission to an MME (e.g., the MME  206 ) associated therewith, via the interface circuitry  420 . In some embodiments, the processing circuitry  410  is further configured to receive an MME DL data notification ack message (e.g., the MME DL data notification ack message  224 ) from the MME via the interface circuitry  420 , in response to the first SGW-C DL data notification message. In some embodiments, the MME DL data notification ack message provides a status information associated with the first SGW-C DL data notification message. 
     In some embodiments, the processing circuitry  410  is further configured to generate a second SGW-C DL data notification message (e.g., the second SGW-C DL data notification message  226 ) for subsequent transmission to a SGSN (e.g., the SGSN  208 ) associated therewith, via the interface circuitry  420 , upon receiving the SGW-U DL data notification message from the SGW-U. In such embodiments, the processing circuitry  410  is further configured to receive a SGSN DL data notification ack message (e.g., the SGSN DL data notification ack message  228 ) from the SGSN via the interface circuitry  420 , in response to the second SGW-C DL data notification message. In some embodiments, the SGSN DL data notification ack message provides a status information associated with the second SGW-C DL data notification message. 
     Upon receiving the MME DL data notification ack message or the SGSN DL data notification ack message, the processing circuitry  410  is configured to generate an SGW-C DL data notification ack message (e.g., the SGW-C DL data notification ack message  230 ) for subsequent transmission to the SGW-U (e.g., the SGW-U  212 ), via the interface circuitry  420 . The SGW-C DL data notification ack message is generated based on the received MME DL data notification ack message or the SGSN DL data notification ack message, and comprises a status information associated with the SGW-U DL data notification message. 
       FIG. 5  illustrates a block diagram of an apparatus  500  for use in a mobility management entity (MME) of a wireless communication network, that facilitates handling downlink (DL) data for an idle mode user equipment (UE) in the network, according to the various embodiments described herein. The apparatus  500  is explained herein with reference to the MME  206  in  FIG. 2 . The apparatus  500  includes a processing circuitry  510  coupled with an interface circuitry  520 . In some embodiments, the apparatus  500  further comprises a memory circuit  530  configured to store instructions and data associated with the SGW-C. In some embodiments, the processing circuitry  510  can comprise one or more processors. In some embodiments, various functions of the processing circuity  510  are performed using different processors. However, in other embodiments, various functions of the processing circuitry  510  can be performed in a single processor. In some embodiments, the memory circuit  530  can be a single memory or a plurality of memories. In some embodiments, the plurality of memories can be in a single location, e.g., a semiconductor chip, or in other embodiments, the plurality of memories can be in different locations. As used herein, the term “circuitry” or “circuit” 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. 
     The interface circuitry  520  may be configured to communicate with other network entities over various interfaces using appropriate networking communication protocols. The interface circuitry  520  may be capable of communicating over any number of wired or wireless communication interfaces. In some embodiments, the interface circuitry  520  may communicate over Ethernet or other computer networking technologies using a variety of physical media interfaces such as, but not limited to, coaxial, twisted-pair compare, and fiber-optics media interfaces. The processing circuitry  510  may be configured to provide higher-layer operations that include generating and processing signals transmitted and received by the interface circuitry  520 . 
     In some embodiments, the apparatus  500  can be included within the MME  206  in  FIG. 2 . The processing circuitry  510  is configured to process a first SGW-C downlink (DL) data notification message (e.g., the first SGW-C downlink (DL) data notification message  222 ) received from a serving gateway control plane (SGW-C) (e.g., the SGW-C  210 ) associated therewith via the interface circuitry  520 . In some embodiments, the first SGW-C DL data notification message indicates an availability of a DL data for an idle mode user equipment (UE) (e.g., the UE  202 ) served by the MME. In some embodiments, the first SGW-C DL data notification message comprises information on one or more of an allocation and retention priority (ARP), evolved packet system (EPS) bearer ID and paging priority indication associated with the DL data. 
     Upon receiving the first SGW-C downlink (DL) data notification message, the processing circuitry  510  is configured to generate an MME DL data notification acknowledge message (e.g., the MME DL data notification acknowledge message  224 ) and provide the generated MME DL data notification acknowledge message to the SGW-C (e.g., the SGW-C  210 ) via the interface circuitry  520 , in response to the first SGW-C DL data notification message. In some embodiments, the MME DL data notification acknowledge message comprises a status information associated with the first SGW-C DL data notification message. In some embodiments, the processing circuitry  510  is further configured to establish evolved packet system (EPS) bearers of the UE (e.g., the UE  202 ) in the network, based on the received first SGW-C DL data notification message as described in the clause 5.3.4.3 of TS 23.401. 
     In some embodiments, if a tracking area update (TAU) procedure with the MME change or a routing area update (RAU) procedure is in progress when the MME, (e.g., the MME  206 ) receives a first SGW-C DL data notification message (e.g., the first SGW-C DL data notification message  222 ) from the SGW-C  210 , the processing circuitry  510  may reject the first SGW-C DL data notification message with an indication that the first SGW-C DL data notification message has been temporarily rejected. In such embodiments, the MME DL data notification ack message to the SGW-C comprises an indication that the first SGW-C DL data notification message has been temporarily rejected. 
     In some embodiments, if the MME (e.g., the MME  206 ) identifies that the UE (e.g., the UE  202 ) is in a power saving state (i.e., a power saving mode) and cannot be reached by paging at the moment, the MME is configured to invoke extended buffering, depending on operator configuration. In such embodiments, the processing circuitry  510  is configured to derive a DL buffering duration time based on an expected time to establish radio bearers to the UE (e.g., the UE  202 ). In such embodiments, the MME DL data notification ack message to the SGW-C  210  comprises a DL buffering requested indication comprising the derived DL buffering duration time. In some embodiments, the DL buffering duration time indicates to the SGW-C, a delay required to send a subsequent first SGW-C DL notification message to the MME. In some embodiments, the memory circuit  530  is configured to store a value for the DL buffering duration time in the context for the UE. 
       FIG. 6  illustrates a flowchart of a method  600  for a serving gateway user plane (SGW-U) of a wireless communication network that facilitates handling downlink (DL) for an idle mode UE in the network, according to one embodiment of the disclosure. The method  600  is described herein with reference to the apparatus  300  in  FIG. 3  and the wireless communication network  200  in  FIG. 2 . In some embodiments, the apparatus  300  is included within the SGW-U  212  in  FIG. 2 . At  602 , a DL data signal comprising a DL data packet for a UE in the network is processed in the processing circuit  310 . At  604 , a serving gateway control plane (SGW-C) associated with the SGW-U that serves the UE is identified at the processing circuit  310 , when the UE is in idle mode. At  606 , the DL data packet in the DL data signal is stored in the memory circuit  330 . At  608 , an SGW-U DL data notification message is selectively generated at the processing circuit  310  and provided to the SGW-C, based on a priority of the received DL data signal, in order to inform the SGW-C about the availability of DL data for the UE. At  610 , a SGW-C DL data notification acknowledge message received from the SGW-C, in response to the SGW-U DL data notification message, is processed at the processing circuit  310 . In some embodiments, the SGW-C DL data notification acknowledge message comprises a status information associated with the SGW-U DL data notification message. 
       FIG. 7  illustrates a flowchart of a method  700  for a serving gateway control plane (SGW-C) of a wireless communication network that facilitates handling downlink (DL) for an idle mode UE in the network, according to one embodiment of the disclosure. The method  700  is described herein with reference to the apparatus  400  in  FIG. 4  and the wireless communication network  200  in  FIG. 2 . In some embodiments, the apparatus  400  is included within the SGW-C  210  in  FIG. 2 . At  702 , an SGW-U downlink (DL) data notification message received from a serving gateway user plane (SGW-U) associated with the SGW-C is processed at the processing circuit  410 . In some embodiments, the SGW-U downlink (DL) data notification message is received via the interface circuitry  420  and the SGW-U DL data notification message indicates an availability of a DL data for a user equipment (UE) served by the SGW-C. 
     At  704 , a first SGW-C DL data notification message is generated at the processing circuit  410 , based on the received SGW-U DL data notification message, and provided to an MME associated with the UE. In some embodiments, the first SGW-C DL data notification message is provided to the MME via the interface circuitry  420  and the first SGW-C DL data notification message indicates an availability of DL data for a UE served by the MME. At  706 , a second SGW-C DL data notification message is generated at the processing circuit  410 , based on the received SGW-U DL data notification message, and provided to an SGSN associated with the UE. In some embodiments, the second SGW-C DL data notification message is provided to the SGSN via the interface circuitry  420  and the second SGW-C DL data notification message indicates an availability of DL data for a UE served by the SGSN. 
     At  708 , an MME DL data notification acknowledge message received from the MME, in response to the first SGW-C DL data notification message, is processed at the processing circuit  410 . In some embodiments, the MME DL data notification acknowledge message is received via the interface circuitry  420  and the MME DL data notification acknowledge message comprises a status information associated with the first SGW-C DL data notification message. At  710 , an SGSN DL data notification acknowledge message received from the SGSN, in response to the second SGW-C DL data notification message, is processed at the processing circuit  410 . In some embodiments, the SGSN DL data notification acknowledge message is received via the interface circuitry  420  and the SGSN DL data notification acknowledge message comprises a status information associated with the second SGW-C DL data notification message. 
     At  712 , an SGW-C DL data notification acknowledge message is generated at the processing circuit  410  and provided to the SGW-U, wherein the SGW-C DL data notification acknowledge message comprises a status information associated with the SGW-U DL data notification message. In some embodiments, the SGW-C DL data notification acknowledge message is generated at the processing circuit  410 , based on the received MME DL data notification acknowledge message. However, in other embodiments, the SGW-C DL data notification acknowledge message is generated at the processing circuit  410 , based on the received SGSN DL data notification acknowledge message. In some embodiments, SGW-C DL data notification acknowledge message is provided to the SGW-U via the interface circuitry  420 . 
       FIG. 8  illustrates a flowchart of a method  800  for a mobility management entity (MME) of a wireless communication network that facilitates handling downlink (DL) for an idle mode UE in the network, according to one embodiment of the disclosure. The method  800  is described herein with reference to the apparatus  500  in  FIG. 5  and the wireless communication network  200  in  FIG. 2 . In some embodiments, the apparatus  500  is included within the MME  206  in  FIG. 2 . At  802 , a first SGW-C downlink (DL) data notification message received from a serving gateway control plane (SGW-C) associated with the MME is processed at the processing circuit  510 . In some embodiments, the first SGW-C DL data notification message is received via the interface circuitry  520  and the first SGW-C DL data notification message indicates an availability of a DL data for a user equipment (UE) served by the MME. At  804 , an MME DL data notification acknowledge message is generated at the processing circuit  510  and provided to the SGW-C, in response to the first SGW-C DL data notification message. In some embodiments, the MME DL data notification acknowledge message comprises a status information associated with the first SGW-C DL data notification message. 
     While the methods are illustrated and described above as a series of acts or events, it will be appreciated that the illustrated ordering of such acts or events are not to be interpreted in a limiting sense. For example, some acts may occur in different orders and/or concurrently with other acts or events apart from those illustrated and/or described herein. In addition, not all illustrated acts may be required to implement one or more aspects or embodiments of the disclosure herein. Also, one or more of the acts depicted herein may be carried out in one or more separate acts and/or phases. 
     Embodiments described herein may be implemented into a system using any suitably configured hardware and/or software.  FIG. 9  illustrates, for one embodiment, example components of an electronic device  900 . In embodiments, the electronic device  900  may be, implement, be incorporated into, or otherwise be a part of a user equipment (UE), an evolved NodeB (eNB), for example. In some embodiments, the electronic device  100  may include application circuitry  102 , baseband circuitry  104 , Radio Frequency (RF) circuitry  106 , front-end module (FEM) circuitry  108  and one or more antennas  110 , coupled together at least as shown. 
     The application circuitry  902  may include one or more application processors. For example, the application circuitry  902  may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The processor(s) may include any combination of general-purpose processors and dedicated processors (e.g., graphics processors, application processors, etc.). The processors may be coupled with and/or may include memory/storage and may be configured to execute instructions stored in the memory/storage to enable various applications and/or operating systems to run on the system. 
     The baseband circuitry  904  may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The baseband circuitry  904  may include one or more baseband processors and/or control logic to process baseband signals received from a receive signal path of the RF circuitry  906  and to generate baseband signals for a transmit signal path of the RF circuitry  906 . Baseband processing circuity  904  may interface with the application circuitry  902  for generation and processing of the baseband signals and for controlling operations of the RF circuitry  906 . For example, in some embodiments, the baseband circuitry  904  may include a second generation (2G) baseband processor  904   a , third generation (3G) baseband processor  904   b , fourth generation (4G) baseband processor  904   c , and/or other baseband processor(s)  904   d  for other existing generations, generations in development or to be developed in the future (e.g., fifth generation (5G), 6G, etc.). The baseband circuitry  904  (e.g., one or more of baseband processors  904   a - d ) may handle various radio control functions that enable communication with one or more radio networks via the RF circuitry  906 . The radio control functions may include, but are not limited to, signal modulation/demodulation, encoding/decoding, radio frequency shifting, etc. In some embodiments, modulation/demodulation circuitry of the baseband circuitry  904  may include Fast-Fourier Transform (FFT), precoding, and/or constellation mapping/demapping functionality. In some embodiments, encoding/decoding circuitry of the baseband circuitry  904  may include convolution, tail-biting convolution, turbo, Viterbi, and/or Low Density Parity Check (LDPC) encoder/decoder functionality. Embodiments of modulation/demodulation and encoder/decoder functionality are not limited to these examples and may include other suitable functionality in other embodiments. 
     In some embodiments, the baseband circuitry  904  may include elements of a protocol stack such as, for example, elements of an evolved universal terrestrial radio access network (EUTRAN) protocol including, for example, physical (PHY), media access control (MAC), radio link control (RLC), packet data convergence protocol (PDCP), and/or radio resource control (RRC) elements. A central processing unit (CPU)  904   e  of the baseband circuitry  904  may be configured to run elements of the protocol stack for signaling of the PHY, MAC, RLC, PDCP and/or RRC layers. In some embodiments, the baseband circuitry may include one or more audio digital signal processor(s) (DSP)  904   f . The audio DSP(s)  904   f  may be include elements for compression/decompression and echo cancellation and may include other suitable processing elements in other embodiments. Components of the baseband circuitry may be suitably combined in a single chip, a single chipset, or disposed on a same circuit board in some embodiments. In some embodiments, some or all of the constituent components of the baseband circuitry  904  and the application circuitry  902  may be implemented together such as, for example, on a system on a chip (SOC). 
     In some embodiments, the baseband circuitry  904  may provide for communication compatible with one or more radio technologies. For example, in some embodiments, the baseband circuitry  904  may support communication with an evolved universal terrestrial radio access network (EUTRAN) and/or other wireless metropolitan area networks (WMAN), a wireless local area network (WLAN), a wireless personal area network (WPAN). Embodiments in which the baseband circuitry  904  is configured to support radio communications of more than one wireless protocol may be referred to as multi-mode baseband circuitry. 
     RF circuitry  906  may enable communication with wireless networks using modulated electromagnetic radiation through a non-solid medium. In various embodiments, the RF circuitry  906  may include switches, filters, amplifiers, etc. to facilitate the communication with the wireless network. RF circuitry  906  may include a receive signal path which may include circuitry to down-convert RF signals received from the FEM circuitry  908  and provide baseband signals to the baseband circuitry  904 . RF circuitry  906  may also include a transmit signal path which may include circuitry to up-convert baseband signals provided by the baseband circuitry  904  and provide RF output signals to the FEM circuitry  908  for transmission. 
     In some embodiments, the RF circuitry  906  may include a receive signal path and a transmit signal path. The receive signal path of the RF circuitry  906  may include mixer circuitry  906   a , amplifier circuitry  906   b  and filter circuitry  906   c . The transmit signal path of the RF circuitry  906  may include filter circuitry  906   c  and mixer circuitry  906   a . RF circuitry  906  may also include synthesizer circuitry  906   d  for synthesizing a frequency for use by the mixer circuitry  906   a  of the receive signal path and the transmit signal path. In some embodiments, the mixer circuitry  906   a  of the receive signal path may be configured to down-convert RF signals received from the FEM circuitry  908  based on the synthesized frequency provided by synthesizer circuitry  906   d . The amplifier circuitry  906   b  may be configured to amplify the down-converted signals and the filter circuitry  906   c  may be a low-pass filter (LPF) or band-pass filter (BPF) configured to remove unwanted signals from the down-converted signals to generate output baseband signals. Output baseband signals may be provided to the baseband circuitry  904  for further processing. In some embodiments, the output baseband signals may be zero-frequency baseband signals, although this is not a requirement. In some embodiments, mixer circuitry  906   a  of the receive signal path may comprise passive mixers, although the scope of the embodiments is not limited in this respect. 
     In some embodiments, the mixer circuitry  906   a  of the transmit signal path may be configured to up-convert input baseband signals based on the synthesized frequency provided by the synthesizer circuitry  906   d  to generate RF output signals for the FEM circuitry  908 . The baseband signals may be provided by the baseband circuitry  904  and may be filtered by filter circuitry  906   c . The filter circuitry  906   c  may include a low-pass filter (LPF), although the scope of the embodiments is not limited in this respect. 
     In some embodiments, the mixer circuitry  906   a  of the receive signal path and the mixer circuitry  906   a  of the transmit signal path may include two or more mixers and may be arranged for quadrature downconversion and/or upconversion respectively. In some embodiments, the mixer circuitry  906   a  of the receive signal path and the mixer circuitry  906   a  of the transmit signal path may include two or more mixers and may be arranged for image rejection (e.g., Hartley image rejection). In some embodiments, the mixer circuitry  906   a  of the receive signal path and the mixer circuitry  906   a  may be arranged for direct downconversion and/or direct upconversion, respectively. In some embodiments, the mixer circuitry  906   a  of the receive signal path and the mixer circuitry  906   a  of the transmit signal path may be configured for super-heterodyne operation. 
     In some embodiments, the output baseband signals and the input baseband signals may be analog baseband signals, although the scope of the embodiments is not limited in this respect. In some alternate embodiments, the output baseband signals and the input baseband signals may be digital baseband signals. In these alternate embodiments, the RF circuitry  906  may include analog-to-digital converter (ADC) and digital-to-analog converter (DAC) circuitry and the baseband circuitry  904  may include a digital baseband interface to communicate with the RF circuitry  906 . 
     In some dual-mode embodiments, a separate radio IC circuitry may be provided for processing signals for each spectrum, although the scope of the embodiments is not limited in this respect. 
     In some embodiments, the synthesizer circuitry  906   d  may be a fractional-N synthesizer or a fractional N/N+1 synthesizer, although the scope of the embodiments is not limited in this respect as other types of frequency synthesizers may be suitable. For example, synthesizer circuitry  906   d  may be a delta-sigma synthesizer, a frequency multiplier, or a synthesizer comprising a phase-locked loop with a frequency divider. 
     The synthesizer circuitry  906   d  may be configured to synthesize an output frequency for use by the mixer circuitry  906   a  of the RF circuitry  906  based on a frequency input and a divider control input. In some embodiments, the synthesizer circuitry  906   d  may be a fractional N/N+1 synthesizer. 
     In some embodiments, frequency input may be provided by a voltage controlled oscillator (VCO), although that is not a requirement. Divider control input may be provided by either the baseband circuitry  904  or the applications processor  902  depending on the desired output frequency. In some embodiments, a divider control input (e.g., N) may be determined from a look-up table based on a channel indicated by the applications processor  902 . 
     Synthesizer circuitry  906   d  of the RF circuitry  906  may include a divider, a delay-locked loop (DLL), a multiplexer and a phase accumulator. In some embodiments, the divider may be a dual modulus divider (DMD) and the phase accumulator may be a digital phase accumulator (DPA). In some embodiments, the DMD may be configured to divide the input signal by either N or N+1 (e.g., based on a carry out) to provide a fractional division ratio. In some example embodiments, the DLL may include a set of cascaded, tunable, delay elements, a phase detector, a charge pump and a D-type flip-flop. In these embodiments, the delay elements may be configured to break a VCO period up into Nd equal packets of phase, where Nd is the number of delay elements in the delay line. In this way, the DLL provides negative feedback to help ensure that the total delay through the delay line is one VCO cycle. 
     In some embodiments, synthesizer circuitry  906   d  may be configured to generate a carrier frequency as the output frequency, while in other embodiments, the output frequency may be a multiple of the carrier frequency (e.g., twice the carrier frequency, four times the carrier frequency) and used in conjunction with quadrature generator and divider circuitry to generate multiple signals at the carrier frequency with multiple different phases with respect to each other. In some embodiments, the output frequency may be a LO frequency (fLO). In some embodiments, the RF circuitry  906  may include an IQ/polar converter. 
     FEM circuitry  908  may include a receive signal path which may include circuitry configured to operate on RF signals received from one or more antennas  910 , amplify the received signals and provide the amplified versions of the received signals to the RF circuitry  906  for further processing. FEM circuitry  908  may also include a transmit signal path which may include circuitry configured to amplify signals for transmission provided by the RF circuitry  906  for transmission by one or more of the one or more antennas  910 . 
     In some embodiments, the FEM circuitry  908  may include a TX/RX switch to switch between transmit mode and receive mode operation. The FEM circuitry may include a receive signal path and a transmit signal path. The receive signal path of the FEM circuitry may include a low-noise amplifier (LNA) to amplify received RF signals and provide the amplified received RF signals as an output (e.g., to the RF circuitry  906 ). The transmit signal path of the FEM circuitry  908  may include a power amplifier (PA) to amplify input RF signals (e.g., provided by RF circuitry  906 ), and one or more filters to generate RF signals for subsequent transmission (e.g., by one or more of the one or more antennas  910 . 
     In some embodiments, the electronic device  900  may include additional elements such as, for example, memory/storage, display, camera, sensor, and/or input/output (I/O) interface. 
     While the apparatus has been illustrated and described with respect to one or more implementations, alterations and/or modifications may be made to the illustrated examples without departing from the spirit and scope of the appended claims. In particular regard to the various functions performed by the above described components or structures (assemblies, devices, circuits, systems, etc.), the terms (including a reference to a “means”) used to describe such components are intended to correspond, unless otherwise indicated, to any component or structure which performs the specified function of the described component (e.g., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary implementations of the invention. 
     In particular regard to the various functions performed by the above described components (assemblies, devices, circuits, systems, etc.), the terms (including a reference to a “means”) used to describe such components are intended to correspond, unless otherwise indicated, to any component or structure which performs the specified function of the described component (e.g., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary implementations of the disclosure. In addition, while a particular feature may have been disclosed with respect to only one of several implementations, such feature may be combined with one or more other features of the other implementations as may be desired and advantageous for any given or particular application. 
     Examples can include subject matter such as a method, means for performing acts or blocks of the method, at least one machine-readable medium including instructions that, when performed by a machine cause the machine to perform acts of the method or of an apparatus or system for concurrent communication using multiple communication technologies according to embodiments and examples described herein. 
     Example 1 is an apparatus for use in a serving gateway user plane (SGW-U) of an evolved packet core (EPC) of a wireless communication network, comprising a memory and one or more processors configured to process a downlink (DL) data signal comprising a DL data packet for a user equipment (UE) in the network; buffer the DL data packet; identify a serving gateway control plane (SGW-C) associated with the SGW-U that serves the UE, when the UE is in idle mode; and provide an SGW-U DL data notification message to the SGW-C, generated selectively based on a priority of the received DL data signal, in order to inform the SGW-C about the availability of DL data for the UE. 
     Example 2 is an apparatus including the subject matter of example 1, wherein the SGW-U DL data notification message to the SGW-C comprises information on one or more of allocation and retention priority (ARP), evolved packet system (EPS) bearer ID and paging priority indication associated with the DL data, and wherein the SGW-U DL data notification message is configured to establish evolved packet system (EPS) bearers of the UE in the network. 
     Example 3 is an apparatus including the subject matter of examples 1-2, including or omitting elements, wherein the processing circuit is further configured to process a SGW-C DL data notification acknowledge message received from the SGW-C, in response to the SGW-U DL data notification message provided to the SGW-C, wherein the SGW-C DL data notification acknowledge message comprises a status information associated with the SGW-U DL data notification message. 
     Example 4 is an apparatus including the subject matter of examples 1-3, including or omitting elements, wherein the processing circuit is configured to drop the DL data packet and not generate the SGW-U DL data notification message to the SGW-C, when the DL data packet is received on a low priority bearer, based on a request from the SGW-C or a mobility management entity (MME) associated therewith. 
     Example 5 is an apparatus including the subject matter of examples 1-4, including or omitting elements, wherein the processing circuit is further configured to introduce a predetermined delay prior to providing the SGW-U DL data notification message to the SGW-C, based on a request to delay sending the SGW-U DL data notification message to the SGW-C, from the SGW-C or a mobility management entity (MME) associated therewith. 
     Example 6 is an apparatus including the subject matter of examples 1-5, including or omitting elements, wherein the SGW-C DL data notification acknowledge message comprises a DL buffering requested indication comprising the DL buffering duration time that indicates a time required to establish radio bearers of the UE, in order to send the DL data to the UE. 
     Example 7 is an apparatus including the subject matter of examples 1-6, including or omitting elements, wherein the processing circuit is further configured to introduce a delay corresponding to the DL buffering duration time prior to providing a subsequent SGW-U DL data notification message to the SGW-C, when subsequent data packets are received at the SGW-U before the expiration of the DL buffering duration time. 
     Example 8 is an apparatus including the subject matter of examples 1-7, including or omitting elements, wherein the SGW-C DL data notification acknowledge message comprises an indication that the SGW-U DL data notification message provided to the SGW-C is temporarily rejected by a mobility management entity MME or a service GPRS support node (SGSN) associated therewith. 
     Example 9 is an apparatus including the subject matter of examples 1-8, including or omitting elements, wherein the processing circuit is further configured to start a locally configured guard timer having a predetermined delay associated therewith, and buffer subsequent DL data packets, until a modify bearer request message is received from an MME or an SGSN associated therewith, or the guard timer is expired, when the SGW-C DL data notification acknowledge message comprises an indication that the SGW-U DL data notification message is temporarily rejected. 
     Example 10 is an apparatus including the subject matter of examples 1-9, including or omitting elements, wherein the processing circuit, upon receiving the modify bearer request message, is configured to provide the SGW-U DL data notification message again to the SGW-C, for subsequent transmission to an MME or a SGSN from which the modify bearer request message is received. 
     Example 11 is an apparatus including the subject matter of examples 1-10, including or omitting elements, wherein the processing circuit is configured to release the buffered DL data packets, if the guard timer is expired or a delete session request message is received from an MME or a SGSN associated therewith, before receiving the modify bearer request message. 
     Example 12 is an apparatus for use in a serving gateway control plane (SGW-C) of a wireless communication network, comprising a processing circuit configured to process an SGW-U downlink (DL) data notification message received from a serving gateway user plane (SGW-U) associated therewith, wherein the SGW-U DL data notification message indicates an availability of a DL data for a user equipment (UE) served by the SGW-C; and provide a SGW-C DL data notification acknowledge message to the SGW-U, in response to the SGW-U DL data notification message, wherein the SGW-C DL data notification acknowledge message comprises a status information associated with the SGW-U DL data notification message. 
     Example 13 is an apparatus including the subject matter of example 12, wherein the processing circuit is further configured to provide a first SGW-C DL data notification message, generated based on the received SGW-U DL data notification message, to a mobility management entity (MME) associated with the UE, prior to providing the SGW-C DL data notification acknowledge message to the SGW-U and wherein the first SGW-C DL data notification message provides to the MME, an indication of the availability of the DL data for the UE. 
     Example 14 is an apparatus including the subject matter of examples 12-13, including or omitting elements, wherein the first SGW-C DL data notification message to the SGW-C comprises information on one or more of an allocation and retention priority (ARP), evolved packet system (EPS) bearer ID and paging priority indication associated with the DL data, and wherein the first SGW-C DL data notification message is configured to establish evolved packet system (EPS) bearers of the UE in the network. 
     Example 15 is an apparatus including the subject matter of examples 12-14, including or omitting elements, wherein the processing circuit is further configured to provide a second SGW-C DL data notification message, generated based on the received SGW-U DL data notification message, to a service GPRS support node (SGSN) associated with the UE, in order to transfer the DL data to the UE, prior to providing the SGW-C DL data notification acknowledge message to the SGW-U, wherein the second SGW-C DL data notification message comprises an indication of the availability of the DL data for the UE. 
     Example 16 is an apparatus including the subject matter of examples 12-15, including or omitting elements, wherein the processing circuit is further configured to process an MME DL data notification acknowledge message received from the MME, in response to the first SGW-C DL data notification message, prior to providing the SGW-C DL data notification acknowledge message to the SGW-U, wherein the MME DL data notification acknowledge message comprises a status information associated with the first SGW-C DL data notification message, and wherein the SGW-C DL data notification acknowledge message to the SGW-U is generated based on the received MME DL data notification acknowledge message. 
     Example 17 is an apparatus including the subject matter of examples 12-16, including or omitting elements, wherein the processing circuit is further configured to process an SGSN DL data notification acknowledge message received from the SGSN, in response to the second SGW-C DL data notification message from the SGW-C, prior to providing the SGW-C DL data notification acknowledge message to the SGW-U, wherein the SGSN DL data notification acknowledge message comprises a status information associated with the second SGW-C DL data notification message, and wherein the SGW-C DL data notification acknowledge message to the SGW-U is generated based on the received SGSN DL data notification acknowledge message. 
     Example 18 is an apparatus for use in a mobility management entity (MME) of a wireless communication network, comprising a processing circuit configured to process a first SGW-C downlink (DL) data notification message received from a serving gateway control plane (SGW-C) associated therewith, wherein the first SGW-C DL data notification message indicates an availability of a DL data for a user equipment (UE) served by the MME; and provide an MME DL data notification acknowledge message to the SGW-C, in response to the first SGW-C DL data notification message, wherein the MME DL data notification acknowledge message comprises a status information associated with the first SGW-C DL data notification message. 
     Example 19 is an apparatus including the subject matter of example 18, wherein the first SGW-C DL data notification message comprises information on one or more of an allocation and retention priority (ARP), evolved packet system (EPS) bearer ID and paging priority indication associated with the DL data, and wherein the MME is configured to establish evolved packet system (EPS) bearers of the UE in the network, based on the received first SGW-C DL data notification message. 
     Example 20 is an apparatus including the subject matter of examples 18-19, including or omitting elements, wherein the processing circuit is further configured to derive a DL buffering duration time required to establish radio bearers of the UE, when the UE is in a power saving mode, and wherein the MME DL data notification acknowledge message comprises a DL buffering requested indication comprising the DL buffering duration time. 
     Example 21 is an apparatus including the subject matter of examples 18-20, including or omitting elements, wherein the processing circuit is configured to reject the first SGW-C DL data notification message from the SGW-C, when a tracking area update (TAU) procedure with the MME change or a routing area update (RAU) procedure of the MME is in progress, and wherein the MME DL data notification acknowledge message comprises an indication that the first SGW-C DL data notification message has been temporarily rejected. 
     Example 22 is a computer-readable medium storing executable instructions that, in response to execution, cause one or more processors of a serving gateway user plane (SGW-U) of an evolved packet core (EPC) of a wireless communication network, to perform operations comprising processing a downlink (DL) data signal comprising a DL data packet for a user equipment (UE) in the network; buffering the DL data packet; identifying a serving gateway control plane (SGW-C) associated with the SGW-U that serves the UE, when the UE is in idle mode; and providing an SGW-U DL data notification message to the SGW-C, generated selectively based on a priority of the received DL data signal, in order to inform the SGW-C about the availability of DL data for the UE. 
     Example 23 is a computer-readable medium including the subject matter of example 22, wherein the SGW-U DL data notification message to the SGW-C comprises information on one or more of allocation and retention priority (ARP), evolved packet system (EPS) bearer ID and paging priority indication associated with the DL data, and wherein the SGW-U DL data notification message is configured to establish evolved packet system (EPS) bearers of the UE in the network. 
     Example 24 is a computer-readable medium including the subject matter of examples 22-23, including or omitting elements, further cause the one or more processors to process a SGW-C DL data notification acknowledge message received from the SGW-C, in response to the SGW-U DL data notification message provided to the SGW-C, wherein the SGW-C DL data notification acknowledge message comprises a status information associated with the SGW-U DL data notification message. 
     Example 25 is a computer-readable medium including the subject matter of examples 22-24, including or omitting elements, further cause the one or more processors to drop the DL data packet and not generate the SGW-U DL data notification message to the SGW-C, when the DL data packet is received on a low priority bearer, based on a request from the SGW-C or a mobility management entity (MME) associated therewith. 
     Example 26 is a computer-readable medium including the subject matter of examples 22-25, including or omitting elements, further cause the one or more processors to introduce a predetermined delay prior to providing the SGW-U DL data notification message to the SGW-C, based on a request to delay sending the SGW-U DL data notification message to the SGW-C, from the SGW-C or a mobility management entity (MME) associated therewith. 
     Example 27 is a computer-readable medium including the subject matter of examples 22-26, including or omitting elements, wherein the SGW-C DL data notification acknowledge message comprises a DL buffering requested indication comprising the DL buffering duration time that indicates a time required to establish radio bearers of the UE, in order to send the DL data to the UE. 
     Example 28 is a computer-readable medium including the subject matter of examples 22-27, including or omitting elements, further cause the one or more processors to introduce a delay corresponding to the DL buffering duration time prior to providing a subsequent SGW-U DL data notification message to the SGW-C, when subsequent data packets are received at the SGW-U before the expiration of the DL buffering duration time. 
     Example 29 is a computer-readable medium including the subject matter of examples 22-28, including or omitting elements, wherein the SGW-C DL data notification acknowledge message comprises an indication that the SGW-U DL data notification message provided to the SGW-C is temporarily rejected by a mobility management entity MME or a service GPRS support node (SGSN) associated therewith. 
     Example 30 is a computer-readable medium including the subject matter of examples 22-29, including or omitting elements, further cause the one or more processors to start a locally configured guard timer having a predetermined delay associated therewith, and buffer subsequent DL data packets, until a modify bearer request message is received from an MME or an SGSN associated therewith, or the guard timer is expired, when the SGW-C DL data notification acknowledge message comprises an indication that the SGW-U DL data notification message is temporarily rejected. 
     Example 31 is a computer-readable medium including the subject matter of examples 22-30, including or omitting elements, upon receiving the modify bearer request message, further cause the one or more processors to provide the SGW-U DL data notification message again to the SGW-C, for subsequent transmission to an MME or a SGSN from which the modify bearer request message is received. 
     Example 32 is a computer-readable medium including the subject matter of examples 22-31, including or omitting elements, further cause the one or more processors to release the buffered DL data packets, if the guard timer is expired or a delete session request message is received from an MME or a SGSN associated therewith, before receiving the modify bearer request message. 
     Example 33 is a computer-readable medium storing executable instructions that, in response to execution, cause one or more processors of a serving gateway control plane (SGW-C) of a wireless communication network, to perform operations comprising processing an SGW-U downlink (DL) data notification message received from a serving gateway user plane (SGW-U) associated therewith, wherein the SGW-U DL data notification message indicates an availability of a DL data for a user equipment (UE) served by the SGW-C; and providing a SGW-C DL data notification acknowledge message to the SGW-U, in response to the SGW-U DL data notification message, wherein the SGW-C DL data notification acknowledge message comprises a status information associated with the SGW-U DL data notification message. 
     Example 34 is a computer-readable medium including the subject matter of example 33, further cause the one or more processors to provide a first SGW-C DL data notification message, generated based on the received SGW-U DL data notification message, to a mobility management entity (MME) associated with the UE, prior to providing the SGW-C DL data notification acknowledge message to the SGW-U and wherein the first SGW-C DL data notification message provides to the MME, an indication of the availability of the DL data for the UE. 
     Example 35 is a computer-readable medium including the subject matter of examples 33-34, including or omitting elements, wherein the first SGW-C DL data notification message to the SGW-C comprises information on one or more of an allocation and retention priority (ARP), evolved packet system (EPS) bearer ID and paging priority indication associated with the DL data, and wherein the first SGW-C DL data notification message is configured to establish evolved packet system (EPS) bearers of the UE in the network. 
     Example 36 is a computer-readable medium including the subject matter of examples 33-35, including or omitting elements, further cause the one or more processors to provide a second SGW-C DL data notification message, generated based on the received SGW-U DL data notification message, to a service GPRS support node (SGSN) associated with the UE, in order to transfer the DL data to the UE, prior to providing the SGW-C DL data notification acknowledge message to the SGW-U, wherein the second SGW-C DL data notification message comprises an indication of the availability of the DL data for the UE. 
     Example 37 is a computer-readable medium including the subject matter of examples 33-36, including or omitting elements, further cause the one or more processors to process an MME DL data notification acknowledge message received from the MME, in response to the first SGW-C DL data notification message, prior to providing the SGW-C DL data notification acknowledge message to the SGW-U, wherein the MME DL data notification acknowledge message comprises a status information associated with the first SGW-C DL data notification message, and wherein the SGW-C DL data notification acknowledge message to the SGW-U is generated based on the received MME DL data notification acknowledge message. 
     Example 38 is a computer-readable medium including the subject matter of examples 33-37, including or omitting elements, further cause the one or more processors to process an SGSN DL data notification acknowledge message received from the SGSN, in response to the second SGW-C DL data notification message from the SGW-C, prior to providing the SGW-C DL data notification acknowledge message to the SGW-U, wherein the SGSN DL data notification acknowledge message comprises a status information associated with the second SGW-C DL data notification message, and wherein the SGW-C DL data notification acknowledge message to the SGW-U is generated based on the received SGSN DL data notification acknowledge message. 
     Example 39 is a computer-readable medium storing executable instructions that, in response to execution, cause one or more processors of a mobility management entity (MME) of a wireless communication network, to perform operations comprising processing a first SGW-C downlink (DL) data notification message received from a serving gateway control plane (SGW-C) associated therewith, wherein the first SGW-C DL data notification message indicates an availability of a DL data for a user equipment (UE) served by the MME; and providing an MME DL data notification acknowledge message to the SGW-C, in response to the first SGW-C DL data notification message, wherein the MME DL data notification acknowledge message comprises a status information associated with the first SGW-C DL data notification message. 
     Example 40 is a computer-readable medium including the subject matter of example 39, wherein the first SGW-C DL data notification message comprises information on one or more of an allocation and retention priority (ARP), evolved packet system (EPS) bearer ID and paging priority indication associated with the DL data, and wherein the MME is configured to establish evolved packet system (EPS) bearers of the UE in the network, based on the received first SGW-C DL data notification message. 
     Example 41 is a computer-readable medium including the subject matter of examples 39-40, including or omitting elements, further cause the one or more processors to derive a DL buffering duration time required to establish radio bearers of the UE, when the UE is in a power saving mode, and wherein the MME DL data notification acknowledge message comprises a DL buffering requested indication comprising the DL buffering duration time. 
     Example 42 is a computer-readable medium including the subject matter of examples 39-41, including or omitting elements, further cause the one or more processors to reject the first SGW-C DL data notification message from the SGW-C, when a tracking area update (TAU) procedure with the MME change or a routing area update (RAU) procedure of the MME is in progress, and wherein the MME DL data notification acknowledge message comprises an indication that the first SGW-C DL data notification message has been temporarily rejected. 
     Example 43 is an apparatus for use in a serving gateway user plane (SGW-U) of an evolved packet core (EPC) of a wireless communication network, comprising means for processing a downlink (DL) data signal comprising a DL data packet for a user equipment (UE) in the network; means for buffering the DL data packet; means for identifying a serving gateway control plane (SGW-C) associated with the SGW-U that serves the UE, when the UE is in idle mode; and means for providing an SGW-U DL data notification message to the SGW-C, generated selectively based on a priority of the received DL data signal, in order to inform the SGW-C about the availability of DL data for the UE. In some embodiments, the means for performing the various functions comprises one or more processors, wherein the various functions are performed in different processors. However, in other embodiments, the various functions can be performed in a same processor. 
     Example 44 is an apparatus including the subject matter of example 43, wherein the SGW-U DL data notification message to the SGW-C comprises information on one or more of allocation and retention priority (ARP), evolved packet system (EPS) bearer ID and paging priority indication associated with the DL data, and wherein the SGW-U DL data notification message is configured to establish evolved packet system (EPS) bearers of the UE in the network. 
     Example 45 is an apparatus including the subject matter of examples 43-44, including or omitting elements, further comprising means for processing a SGW-C DL data notification acknowledge message received from the SGW-C, in response to the SGW-U DL data notification message provided to the SGW-C, wherein the SGW-C DL data notification acknowledge message comprises a status information associated with the SGW-U DL data notification message. 
     Example 46 is an apparatus including the subject matter of examples 43-45, including or omitting elements, further comprising means for dropping the DL data packet and not generating the SGW-U DL data notification message to the SGW-C, when the DL data packet is received on a low priority bearer, based on a request from the SGW-C or a mobility management entity (MME) associated therewith. 
     Example 47 is an apparatus including the subject matter of examples 43-46, including or omitting elements, further comprising means for introducing a predetermined delay prior to providing the SGW-U DL data notification message to the SGW-C, based on a request to delay sending the SGW-U DL data notification message to the SGW-C, from the SGW-C or a mobility management entity (MME) associated therewith. 
     Example 48 is an apparatus including the subject matter of examples 43-47, including or omitting elements, wherein the SGW-C DL data notification acknowledge message comprises a DL buffering requested indication comprising the DL buffering duration time that indicates a time required to establish radio bearers of the UE, in order to send the DL data to the UE. 
     Example 49 is an apparatus including the subject matter of examples 43-48, including or omitting elements, further comprising means for introducing a delay corresponding to the DL buffering duration time prior to providing a subsequent SGW-U DL data notification message to the SGW-C, when subsequent data packets are received at the SGW-U before the expiration of the DL buffering duration time. 
     Example 50 is an apparatus including the subject matter of examples 43-49, including or omitting elements, wherein the SGW-C DL data notification acknowledge message comprises an indication that the SGW-U DL data notification message provided to the SGW-C is temporarily rejected by a mobility management entity MME or a service GPRS support node (SGSN) associated therewith. 
     Example 51 is an apparatus including the subject matter of examples 43-50, including or omitting elements, further comprising means for starting a locally configured guard timer having a predetermined delay associated therewith, and buffering subsequent DL data packets, until a modify bearer request message is received from an MME or an SGSN associated therewith, or the guard timer is expired, when the SGW-C DL data notification acknowledge message comprises an indication that the SGW-U DL data notification message is temporarily rejected. 
     Example 52 is an apparatus including the subject matter of examples 43-51, including or omitting elements, further comprising means for providing the SGW-U DL data notification message again to the SGW-C, upon receiving the modify bearer request message, for subsequent transmission to an MME or a SGSN from which the modify bearer request message is received. 
     Example 53 is an apparatus including the subject matter of examples 43-52, including or omitting elements, further comprising means for releasing the buffered DL data packets, if the guard timer is expired or a delete session request message is received from an MME or a SGSN associated therewith, before receiving the modify bearer request message. 
     Example 54 is an apparatus including the subject matter of examples 43-53, including or omitting elements, further comprising means for storing the buffered data packet. In some embodiments, the means for performing the above function comprises a memory. 
     Example 55 is an apparatus for use in a serving gateway control plane (SGW-C) of a wireless communication network, comprising means for processing an SGW-U downlink (DL) data notification message received from a serving gateway user plane (SGW-U) associated therewith, wherein the SGW-U DL data notification message indicates an availability of a DL data for a user equipment (UE) served by the SGW-C; and means for providing a SGW-C DL data notification acknowledge message to the SGW-U, in response to the SGW-U DL data notification message, wherein the SGW-C DL data notification acknowledge message comprises a status information associated with the SGW-U DL data notification message. In some embodiments, the means for performing the various functions comprises one or more processors, wherein the various functions are performed in different processors. However, in other embodiments, the various functions can be performed in a same processor. 
     Example 56 is an apparatus including the subject matter of example 55, further comprising means for providing a first SGW-C DL data notification message, generated based on the received SGW-U DL data notification message, to a mobility management entity (MME) associated with the UE, prior to providing the SGW-C DL data notification acknowledge message to the SGW-U and wherein the first SGW-C DL data notification message provides to the MME, an indication of the availability of the DL data for the UE. 
     Example 57 is an apparatus including the subject matter of examples 55-56, including or omitting elements, wherein the first SGW-C DL data notification message to the SGW-C comprises information on one or more of an allocation and retention priority (ARP), evolved packet system (EPS) bearer ID and paging priority indication associated with the DL data, and wherein the first SGW-C DL data notification message is configured to establish evolved packet system (EPS) bearers of the UE in the network. 
     Example 58 is an apparatus including the subject matter of examples 55-57, including or omitting elements, further comprising means for providing a second SGW-C DL data notification message, generated based on the received SGW-U DL data notification message, to a service GPRS support node (SGSN) associated with the UE, in order to transfer the DL data to the UE, prior to providing the SGW-C DL data notification acknowledge message to the SGW-U, wherein the second SGW-C DL data notification message comprises an indication of the availability of the DL data for the UE. 
     Example 59 is an apparatus including the subject matter of examples 55-58, including or omitting elements, further comprising means for processing an MME DL data notification acknowledge message received from the MME, in response to the first SGW-C DL data notification message, prior to providing the SGW-C DL data notification acknowledge message to the SGW-U, wherein the MME DL data notification acknowledge message comprises a status information associated with the first SGW-C DL data notification message, and wherein the SGW-C DL data notification acknowledge message to the SGW-U is generated based on the received MME DL data notification acknowledge message. 
     Example 60 is an apparatus including the subject matter of examples 55-59, including or omitting elements, further comprising means for processing an SGSN DL data notification acknowledge message received from the SGSN, in response to the second SGW-C DL data notification message from the SGW-C, prior to providing the SGW-C DL data notification acknowledge message to the SGW-U, wherein the SGSN DL data notification acknowledge message comprises a status information associated with the second SGW-C DL data notification message, and wherein the SGW-C DL data notification acknowledge message to the SGW-U is generated based on the received SGSN DL data notification acknowledge message. 
     Example 61 is an apparatus for use in a mobility management entity (MME) of a wireless communication network, comprising means for processing a first SGW-C downlink (DL) data notification message received from a serving gateway control plane (SGW-C) associated therewith, wherein the first SGW-C DL data notification message indicates an availability of a DL data for a user equipment (UE) served by the MME; and means for providing an MME DL data notification acknowledge message to the SGW-C, in response to the first SGW-C DL data notification message, wherein the MME DL data notification acknowledge message comprises a status information associated with the first SGW-C DL data notification message. In some embodiments, the means for performing the various functions comprises one or more processors, wherein the various functions are performed in different processors. However, in other embodiments, the various functions can be performed in a same processor. 
     Example 62 is an apparatus including the subject matter of example 61, wherein the first SGW-C DL data notification message comprises information on one or more of an allocation and retention priority (ARP), evolved packet system (EPS) bearer ID and paging priority indication associated with the DL data, and wherein the MME is configured to establish evolved packet system (EPS) bearers of the UE in the network, based on the received first SGW-C DL data notification message. 
     Example 63 is an apparatus including the subject matter of examples 61-62, including or omitting elements, further comprising means for deriving a DL buffering duration time required to establish radio bearers of the UE, when the UE is in a power saving mode, and wherein the MME DL data notification acknowledge message comprises a DL buffering requested indication comprising the DL buffering duration time. 
     Example 64 is an apparatus including the subject matter of examples 61-63, including or omitting elements, further comprising means for rejecting the first SGW-C DL data notification message from the SGW-C, when a tracking area update (TAU) procedure with the MME change or a routing area update (RAU) procedure of the MME is in progress, and wherein the MME DL data notification acknowledge message comprises an indication that the first SGW-C DL data notification message has been temporarily rejected. 
     Various illustrative logics, logical blocks, modules, and circuits described in connection with aspects disclosed herein can be implemented or performed with a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform functions described herein. A general-purpose processor can be a microprocessor, but, in the alternative, processor can be any conventional processor, controller, microcontroller, or state machine. 
     The above description of illustrated embodiments of the subject disclosure, including what is described in the Abstract, is not intended to be exhaustive or to limit the disclosed embodiments to the precise forms disclosed. While specific embodiments and examples are described herein for illustrative purposes, various modifications are possible that are considered within the scope of such embodiments and examples, as those skilled in the relevant art can recognize. 
     In this regard, while the disclosed subject matter has been described in connection with various embodiments and corresponding Figures, where applicable, it is to be understood that other similar embodiments can be used or modifications and additions can be made to the described embodiments for performing the same, similar, alternative, or substitute function of the disclosed subject matter without deviating therefrom. Therefore, the disclosed subject matter should not be limited to any single embodiment described herein, but rather should be construed in breadth and scope in accordance with the appended claims below. 
     In particular regard to the various functions performed by the above described components (assemblies, devices, circuits, systems, etc.), the terms (including a reference to a “means”) used to describe such components are intended to correspond, unless otherwise indicated, to any component or structure which performs the specified function of the described component (e.g., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary implementations of the disclosure. In addition, while a particular feature may have been disclosed with respect to only one of several implementations, such feature may be combined with one or more other features of the other implementations as may be desired and advantageous for any given or particular application.

Metadata:
Filing Date: 20160830
Publication Date: 20210914
Grant Date: 20210914
Priority Date: 20151106
Inventors: SHAN, CHANGHONG
Assignee: APPLE INC
CPC Classifications: [{"code": "H04W76/27", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W76/22", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W76/22", "inventive": true, "first": false, "tree": "[]"}, {"code": "Y02D30/70", "inventive": false, "first": false, "tree": "[]"}, {"code": "Y02D30/70", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W88/16", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W52/0229", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04W68/005", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W52/0229", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04W76/27", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W88/16", "inventive": true, "first": false, "tree": "[]"}, {"code": "Y02D30/70", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W68/005", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W76/22", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W52/0229", "inventive": true, "first": true, "tree": "[]"}]
Family ID: 56894307