Abstract:
A wireless communication system connects User Equipment (UE) to Mobility Management Entities (MMEs). The wireless communication system receives a connection message from the UE. The wireless communication system connects the UE to a first MME responsive to the connection message. The wireless communication system performs MME re-selection for the UE responsive to the connection message. The wireless communication system connects the UE to a second MME responsive to the MME re-selection.

Description:
RELATED CASES 
       [0001]    This patent application is a continuation of U.S. patent application Ser. No. 14/826,302 that was filed on Aug. 14, 2015 and is entitled “LONG TERM EVOLUTION COMMUNICATION SYSTEM TO PERFORM A MOBILITY MANAGEMENT ENTITY RESELECTION.” U.S. patent application Ser. No. 14/826,302 is hereby incorporated by reference into this patent application. 
     
    
     TECHNICAL BACKGROUND 
       [0002]    Wireless data allows users to access services such as mobile Internet, video calling, streaming media, messaging, email, etc. Mobile devices such as laptops and smartphones allow users to access wireless data services. Wireless data may use wireless protocols such as Long Term Evolution (LTE). Wireless communication networks providing wireless data may comprise various network elements, such as wireless access points, Mobility Management Entities (MMEs), Serving Gateways (S-GWs), PDN Gateways (P-GWs), Home Subscriber Servers (HSSs)—including other elements and systems. 
         [0003]    The MMEs control the high-level operation of wireless communication devices in the wireless communication network. The MMEs may perform functions, such as network access control (i.e. authentication and authorization), radio resource management, mobility management, roaming management, paging, tracking area management, UE location monitoring, load balancing between S-GWs—among other functions. The MMEs may send signaling messages about issues such as security and the management of data streams. The MMEs may also retain location information for each mobile device and select the appropriate gateway during the initial registration process. The MMEs are manufactured by different manufacturers and may use different software. 
         [0004]    A network operator may select a MME using a scheduling algorithm (i.e. Round-Robin (RR)). The MME may also be selected using the Global Unique Temporary Identifier (GUTI) transferred by the mobile device. Network operators may desire to assign users to a specific MME based on the criteria such as the services requested by the user. Users may also desire to select a specific MME. Unfortunately, current user MME selection is insufficient. 
       OVERVIEW 
       [0005]    A wireless communication system connects User Equipment (UE) to Mobility Management Entities (MMEs). The wireless communication system receives a connection message from the UE. The wireless communication system connects the UE to a first MME responsive to the connection message. The wireless communication system performs MME re-selection for the UE responsive to the connection message. The wireless communication system connects the UE to a second MME responsive to the MME re-selection. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    The following description and associated figures teach the best mode of the invention. For the purpose of teaching inventive principles, some conventional aspects of the best mode may be simplified or omitted. The following claims specify the scope of the invention. Note that some aspects of the best mode may not fall within the scope of the invention as specified by the claims. Thus, those skilled in the art will appreciate variations from the best mode that fall within the scope of the invention. Those skilled in the art will appreciate that the features described below can be combined in various ways to form multiple variations of the invention. As a result, the invention is not limited to the specific examples described below, but only by the claims and their equivalents. 
           [0007]      FIG. 1  illustrates a Long Term Evolution (LTE) communication system to perform a Mobility Management Entity (MME) reselection. 
           [0008]      FIG. 2  illustrates the operation of the LTE communication system to perform the MME reselection. 
           [0009]      FIG. 3  illustrates the operation of the LTE communication system to perform the MME reselection. 
           [0010]      FIG. 4  illustrates a LTE communication system to perform a MME reselection. 
           [0011]      FIG. 5  illustrates an example of an MME to perform a MME reselection. 
           [0012]      FIG. 6  illustrates an example of User Equipment to perform a MME reselection 
       
    
    
     DETAILED DESCRIPTION 
       [0013]    The following description and associated figures teach the best mode of the invention. For the purpose of teaching inventive principles, some conventional aspects of the best mode may be simplified or omitted. The following claims specify the scope of the invention. Note that some aspects of the best mode may not fall within the scope of the invention as specified by the claims. Thus, those skilled in the art will appreciate variations from the best mode that fall within the scope of the invention. Those skilled in the art will appreciate that the features described below can be combined in various ways to form multiple variations of the invention. As a result, the invention is not limited to the specific examples described below, but only by the claims and their equivalents. 
         [0014]      FIG. 1  illustrates Long Term Evolution (LTE) communication system  100  to perform a Mobility Management Entity (MME) reselection. LTE communication system  100  includes User Equipment (UE)  101  and LTE communication network  120 . LTE communication network  120  includes access nodes  121 - 123 , MMEs  131 - 133 , User Profile Database  141 , and MME selection Database  142 . Although not required, User Profile Database  141  may comprise a Home Subscriber Server (HSS) or any other database containing subscriber or user information. In some examples, MME selection database  142  comprises a Domain Name Server (DNS). 
         [0015]    UE  101  communicates with access nodes  121 - 123  over wireless communication link  111 . Access nodes  121 - 123  communicate with MMEs  131 - 133  over communication link  112 . In some examples, communication link  112  comprises backhaul links of LTE communication network  120 . MMEs  131 - 133  communicate with User Profile DB  141  and MME selection DB  142  over communication link  113 . In some examples, communication link  113  uses database access protocols, such as Diameter. LTE communication system  100  may include other elements that are omitted for clarity 
         [0016]    In operation, access point  121  receives a Radio Resource Control (RRC) connection message for a communication session from UE  101 . Access point  121  assigns MME  131  to UE  101 . Access point  121  may assign MME  131  using a load balancing algorithm, scheduling algorithm (i.e. Round-robin scheduling), user selection, user input, device location, session requirements, device capabilities, RF signal/quality, Globally Unique Temporary Identifier (GUTI), establishment clause, Public Land Mobile Network (PLMN) ID. MMEs may be assigned to specific users and/or services. For example, MME  131  previously assigns UE  101  a GUTI. In the RRC connection message, UE  101  may also transmit the previously assigned GUTI. Access point  121  can use the GUTI transmitted by UE  101  to identify MME  131  as previously assigned to UE  101  and reassigns MME  131  to UE  101 . In some cases, if access point  121  is not connected to MME  131 , then access point  121  may select or assign a new MME to serve UE  101 . 
         [0017]    MME  131  transfers a request for a user profile associated with UE  101  to User Profile database  141 . MME  131  receives the user profile associated with UE  101  from User Profile database  141 . In some examples, user profile includes data such as network ID, PLMN ID, requested services, user QoS, International Mobile Subscriber Identity (IMSI), Application ID, Access Point Names (APNs)—APNs may include default QCIs and bearer metadata (including Aggregate maximum Bit-Rate (AMBR), maximum Bit-Rate, and latency). 
         [0018]    MME  131  performs a MME reselection based on the user profile to determine UE  101  should be assigned to MME  132 . For example, MME  132  may be selected based on the requested services associated with the communication session. In other examples, MME  132  may be selected based on the user QoS associated with UE  101 . MME  131  transfers indication of the selection of MME  132  for delivery to UE  101 . In some examples, the MME  132  indication may be transmitted over NAS data between MME  131  and UE  101 . After receiving indication of MME  132  from MME  131 , UE transfers signaling indicating MME  132  to access node  121 . In some examples, UE  101  may transfer another RRC message indicating MME  132 . Access point  121  assigns UE  101  to MME  132  for the communication session. In some examples, access point  121  transfers a S1AP message to MME  132 . 
         [0019]    Although not required, the MME reselection may be triggered by a flag in the RRC message. In some examples, the MME reselection may be triggered by user input, for instance, user input may be received via a user interface that allows the user to select a specific MME. In another example, a user of UE  101  may select a service associated with the communication session and the selected service may be included in the user profile, MME  132  is selected based on the selected service. In some examples, different MMEs may be assigned for different services such as gaming, media streaming, business use, etc. 
         [0020]    Examples of communication sessions include text messaging, voice calling, video calling, media streaming, video conferencing, gaming, emergency communications, emailing, and/or other types of communication sessions—including combinations thereof. In some examples, access nodes  121 - 123  comprise evolved Node Bs (eNodeBs), base transceiver stations, base stations, and/or other access points—including combinations thereof. Examples of UE  101  include wireless communication devices such as a telephone, cellular phone, mobile phone, smartphone, Personal Digital Assistant (PDA), laptop, computer, e-book, eReader, mobile Internet appliance, or some other wireless communication device with a wireless transceiver—including combinations thereof. 
         [0021]      FIG. 2  illustrates the operation of LTE communication system  100  to perform a MME reselection. Access node  121  receives a RRC connection message for a communication session from UE  101  ( 201 ). Although not required, the RRC connection message may comprise a Non-Access Stratum (NAS) message. In some examples, the initial attach request includes information such as PLMN, tracking area, IMSI, requested services, and/or initial MME selection. 
         [0022]    Access node  121  assigns MME  131  to UE  101  ( 202 ). In some examples, access node  121  assigns MME  131  using the establishment clause. For instance, MME  131  may be designated for emergency communications. The RRC message transferred from UE  101  contains an emergency establishment clause. In other examples, access node  121  may assign MME  131  based on MME load. Although not required, UE  101  may indicate MME  131  as a selected MME. In yet other examples, UE  101  may indicate requested services and access point  121  may assign MME  131  based on the requested services. In some examples, user MME selection may override the MME reselection process. In other examples, the MME reselection may override a user MME selection. 
         [0023]    MME  131  transfers a request for a user profile associated with UE  101  to User Profile database  141  ( 203 ). MME  131  receives the user profile associated with UE  101  from User Profile database  141  ( 204 ). MME  131  performs the MME reselection based on the user profile to determine another MME to serve UE  101  ( 205 ). In some examples, MME performs a Domain Name Server (DNS) lookup based on the user profile. 
         [0024]    The MME reselection may also be based on a UE mode such as home, work, and/or time of day (TOD). For instance, a trucking company may desire to track the location and/or movement of its employees during work hours, therefore a UE may be assigned to the “tracking” or corporate MME during work hours. The MME reselection may also be based on a UE mobility status (i.e. mobile, static, secret), location (including Physical Cell ID (PCI)/Cell ID), QoS, and/or other basis—including combinations thereof. For example, a mobile UE may be assigned to a different MME than a static UE. 
         [0025]    In this example, MME  132  is selected to serve UE  101  instead MME  131 . UE  101  may be one of a group of users that is assigned to MME  132  (i.e. first responders, corporate users, etc.). In other examples, UE  101  may be requesting a service assigned to MME  132  (i.e. VoLTE, gaming, media streaming, video conferencing, emergency, business). MME  131  transfers indication of the selection of MME  132  for delivery to UE  101  ( 206 ). UE  101  transfers signaling indicating MME  132  to access point  121  ( 207 ). UE may send a RRC message indicating MME  132  to access point  121 . Access point  121  assigns UE  101  to MME  132  for the communication session ( 208 ). In some examples, access point  121  transfers a S1AP message to MME  132 . In some examples, MME  132  comprises a “smart” MME that is used to assign/reselect MMEs for UEs. 
         [0026]      FIG. 3  illustrates the operation of LTE communication system  100  to perform a MME reselection. Access point  121  receives a RRC connection message for a communication session from UE  101 . Access point  121  assigns MME  131  to UE  101 . For example, access point  121  uses a Round-Robin scheduling algorithm to assign MME  131  to UE  101 . Access point  121  transfers a S1AP message and NAS data to MME  131 . 
         [0027]    MME  131  transfers a request for a user profile associated with UE  101  to User Profile database  141 . MME  131  receives the user profile associated with UE  101  from User Profile database  141 . MME  131  performs the MME reselection based on the user profile to determine that UE  101  should be assigned to MME  132  instead of MME  131 . In some examples, the MME reselect may be performed by other network elements. MME  131  transfers indication of the selection of MME  132  for delivery to UE  101 . UE  101  transfers signaling indicating MME  132  to access node  121 . Access node  121  assigns UE  101  to MME  132  for the communication session. In other examples. MME  131  may perform an MME handover to MME  132 . 
         [0028]    For example, user of UE  101  may be traveling on a train. The user profile for UE  101  may indicate that UE  101  has a velocity greater than  40  mph or some predetermined threshold. MME  131  performs the MME reselection using the user profile and the mobility status to select MME  132  to serve UE  101 . In this example, MME  132  is a MME that serves mobile UEs. 
         [0029]    In another example, the user profile associated with UE  101  indicates UE  101 &#39;s location is at work. MME  131  determines time of day. In some examples, time of day may be determined by other means. Based on the location of UE  101  and TOD, MME  131  selects MME  132  to serve UE  101 . In this example MME  132  may comprise a corporate MME. 
         [0030]    In another example, the user profile associated with UE  101  indicates UE  101 &#39;s location is at home. MME  131  determines time of day. Based on the user profile, location, and TOD, MME  131  selects MME  132  to serve UE  101 . In this example, MME  132  comprises a non-corporate MME. 
         [0031]      FIG. 4  illustrates Long Term Evolution (LTE) communication system  400  to perform a MME reselection. LTE communication system  400  includes User Equipment (UE)  401  and LTE communication network  420 . LTE communication network  420  includes eNodeBs  421 - 423 , MMEs  431 - 433 , Home Subscriber Server (HSS)  441 , and Domain Name Server (DNS)  442 . UE  401  communicates with eNodeBs  421 - 423  over wireless link  411 . ENodeBs  421 - 423  communicate with MMEs  431 - 433  over backhaul link  412 . MMEs  431 - 433  communicate with HSS  441  and DNS  442  over communication link  413 . LTE communication system  400  may include other elements not pictured for clarity. 
         [0032]    ENodeB  421  receives a RRC connection message for a communication session from UE  401 . ENodeB  421  assigns MME  431  to UE  401 . For example, eNodeB  421  assigns MME  431  based on the requested services for the communication session. ENodeB  421  transfers a S1AP message to MME  431 . MME  431  is overloaded and determines it needs to perform a MME reselection to reassign UE  401 . 
         [0033]    MME  431  transfers a request for a user profile associated with UE  401  to HSS  441 . For example, MME  431  transfers a Diameter message to HSS  441  requesting the user profile associated with UE  401 . MME  431  receives the user profile associated with UE  401  from HSS  441 . MME  431  performs the MME reselection based on the user profile to determine UE  401  should be assigned to MME  432 . In some examples, the MME reselection selects MME  431  to serve UE  401 . In some examples, the reselect is triggered by a flag in the RRC message. In other examples, the MME reselect may be triggered when the selected MME is not available. 
         [0034]    MME  431  transfers indication of the selection of MME  432  for delivery to UE  401 . The indication could be in NAS data transferred directly from MME  431  to UE  401 . In other examples, MME  431  transfers the indication to eNodeB  421  and eNodeB  421  transfers the indication to UE  401  over a RRC message. UE  401  transfers signaling indicating MME  432  eNodeB  421 . The signaling may comprise a RRC message. ENodeB  421  assigns UE  401  to MME  432 . In some examples, eNodeB  421  transfers the RRC message via a S1AP message to MME  432 . Although not required, MME  431  may perform a MME handoff to MME  432 . 
         [0035]      FIG. 5  illustrates MME  501 . MME  501  is an example of MMEs  131 - 133  and MMEs  431 - 433 . Although these systems may use alternative configurations and operations. MME  501  comprises communication transceiver system  502  and processing system  503 . Processing system  503  includes processing circuitry  511  and memory system  512  that stores software  513 . Software  513  comprises software modules  514 - 516 . 
         [0036]    Communication transceiver systems  502  comprise components that communicate over communication links such as network cards, ports, RF transceivers, processing circuitry and software, or some other communication components. Communication transceiver systems  502  may be configured to communicate over metallic, wireless, or optical links. Communication transceiver systems  502  may be configured to use TDM, IP, Ethernet, optical networking, wireless protocols, communication signaling, or some other communication format—including combinations thereof. Communication transceiver system  502  may transfer requests for user profile information to the user profile database and indication of the selected MME to the UE. Communication transceiver systems  502  may also receive S1AP messages and user profile information. 
         [0037]    Processor circuitry  511  comprises microprocessor and other circuitry that retrieves and executes operating software  513  from memory system  512 . Processor circuitry  511  may comprise a single device or could be distributed across multiple devices—including devices in different geographic areas. Processor circuitry  511  may be embedded in various types of equipment. Examples of processor circuitry  511  include central processing units, application specific processors, logic devices, and/or any type of computer processing devices—including combinations thereof. Processor circuitry  511  performs the MME reselection to determine an MME to assign to a UE. 
         [0038]    Memory system  512  comprises a non-transitory computer readable storage medium readable by processing system  503  and capable of storing software  513 , such as a disk drive, flash drive, data storage circuitry, or some other hardware memory apparatus—including combinations thereof. Memory system  512  can include volatile and non-volatile, removable and non-removable media implemented in any method or technology for storage of information, such as computer readable instructions, data structures, program modules, or other data—including combinations thereof. Memory system  512  may comprise a single device or could be distributed across multiple devices—including devices in different geographic areas. Memory system  512  may be embedded in various types of equipment. In some examples, a computer apparatus could comprise memory system  512  and software  513 . 
         [0039]    Software  513  comprises computer programs, firmware, or some other form of machine-readable processing instructions. Software  513  may include an operating system, utilities, drivers, network interfaces, applications, or some other type of software. In this example, software  513  comprises user profile module  514 , reselection module  515 , and indication module  515 . Although software  513  could have alternative configurations in other examples. 
         [0040]    Software  513  may be implemented in program instructions and may be executed by processing system  503 . Software  513  may include additional processes, programs, or components, such as operating system software, database software, or application software—including combinations thereof. Software  513  may also comprise firmware or some other form of machine-readable processing instructions executable by processing system  503 . 
         [0041]    When executed, software  513  directs processing system  503  to operate as described herein to perform a MME reselection. In particular, user profile module  514  directs processing system  503  to transfer a request for the user profile. Reselection module  515  directs processing system  503  to perform the MME selection to determine an MME to service a UE. Indication module  516  directs processing system  503  to transfer an indication of the selected MME to the UE. 
         [0042]      FIG. 6  illustrates User Equipment (UE)  601 . UE  601  is an example of UE  101  and UE  401 , although UE  101  and UE  401  could use alternative configurations. UE  601  comprises wireless communication transceiver system  602 , processing system  603 , and user interface  604 . Processing system  603  is linked to wireless communication transceiver system  602  and user interface  604 . Processing system  603  includes processing circuitry  605  and memory device  606  that stores operating software  607 . UE  601  may include other well-known components such as a battery and enclosure that are not shown for clarity. UE  601  may be a telephone, cellular phone, mobile phone, smartphone, personal digital assistant (PDA), computer, laptop, tablet, e-book, mobile Internet appliance, media player, game console, wireless network interface card, or some other wireless communication apparatus—including combinations thereof. 
         [0043]    Wireless communication transceiver system  602  comprises RF communication circuitry and an antenna. The RF communication circuitry typically includes an amplifier, filter, RF modulator, and signal processing circuitry. Wireless communication transceiver system  602  may also include a memory device, software, processing circuitry, or some other communication device. Wireless communication transceiver system  602  may use various communication formats, such as LTE, CDMA, EVDO, WIMAX, GSM, WIFI, HSPA, or some other wireless communication format—including combinations thereof. 
         [0044]    User interface  604  comprises components that interact with a user to receive user inputs and to present media and/or information. User interface  604  may include a speaker, microphone, buttons, lights, display screen, touch screen, touch pad, scroll wheel, communication port, or some other user input/output apparatus—including combinations thereof. User interface  604  may be omitted in some examples. 
         [0045]    Processing circuitry  605  comprises microprocessor and other circuitry that retrieves and executes operating software  607  from memory device  606 . Memory device  606  comprises a non-transitory storage medium, such as a disk drive, flash drive, data storage circuitry, or some other memory apparatus. Processing circuitry  605  is typically mounted on a circuit board that may also hold memory device  606 , portions of wireless communication transceiver system  602 , and user interface  604 . Operating software  607  comprises computer programs, firmware, or some other form of machine-readable processing instructions. Operating software  607  may include an operating system, utilities, drivers, network interfaces, applications, or some other type of software. When executed by processing circuitry  605 , operating software  607  directs processing system  603  to operate user equipment  601  as described herein. 
         [0046]    When executed, software  607  directs processing system  603  to operate as described herein to perform a MME reselection. In particular, RRC module  611  directs processing system  603  to transfer a RRC message indicating the selected MME. 
         [0047]    Referring back to  FIG. 1 , UE  101  comprises Radio Frequency (RF) communication circuitry and an antenna. The RF communication circuitry typically includes an amplifier, filter, modulator, and signal processing circuitry. UE  101  may also include a user interface, memory device, software, processing circuitry, or some other communication components. UE  101  may be a telephone, computer, e-book, mobile Internet appliance, wireless network interface card, media player, game console, or some other wireless communication apparatus—including combinations thereof. 
         [0048]    Access nodes  121 - 123  comprise RF communication circuitry and antennas. The RF communication circuitry typically includes an amplifier, filter, RF modulator, and signal processing circuitry. Access nodes  121 - 123  may also comprise a router, server, memory device, software, processing circuitry, cabling, power supply, network communication interface, structural support, or some other communication apparatus. Access nodes  121 - 123  could be an eNodeB, base transceiver station, base station, Internet access node, telephony service node, wireless data access point, or some other wireless communication system—including combinations thereof. 
         [0049]    MMEs  131 - 133  comprise a computer system and communication interface. MMEs  131 - 133  may also include other components such as a router, server, data storage system, and power supply. MMEs  131 - 133  may reside in a single device or may be distributed across multiple devices. MMEs  131 - 133  are shown externally to access nodes  121 - 123 , but MMEs  131 - 133  could be integrated within the components of access nodes  121 - 123 . 
         [0050]    LTE network  120  comprises network elements that provide communications services to UE  101  through access nodes  121 - 123 . LTE network  120  may comprise switches, wireless access nodes, Internet routers, network gateways, application servers, computer systems, communication links, or some other type of communication equipment—including combinations thereof. 
         [0051]    Wireless link  111  uses the air or space as the transport media. Wireless link  111  may use various protocols, such as Code Division Multiple Access (CDMA), Evolution Data Only (EVDO), Worldwide Interoperability for Microwave Access (WIMAX), Global System for Mobile Communication (GSM), Long Term Evolution (LTE), Wireless Fidelity (WIFI), High Speed Packet Access (HSPA), or some other wireless communication format. Communication links  112 - 113  use metal, glass, air, space, or some other material as the transport media. Communication links  112 - 113  could use various communication protocols, such as Time Division Multiplex (TDM), Internet Protocol (IP), Ethernet, communication signaling, CDMA, EVDO, WIMAX, GSM, LTE, WIFI, HSPA, or some other communication format—including combinations thereof. Communication links  111 - 113  are representative and may include intermediate links, systems, and networks. 
         [0052]    The above description and associated figures teach the best mode of the invention. The following claims specify the scope of the invention. Note that some aspects of the best mode may not fall within the scope of the invention as specified by the claims. Those skilled in the art will appreciate that the features described above can be combined in various ways to form multiple variations of the invention. As a result, the invention is not limited to the specific embodiments described above, but only by the following claims and their equivalents.