WO2017080261A1

WO2017080261A1 - Method and apparatus for updating gateway information

Info

Publication number: WO2017080261A1
Application number: PCT/CN2016/092722
Authority: WO
Inventors: 吴锦花; 宗在峰; 梁爽; 卢飞; 周晓云
Original assignee: 中兴通讯股份有限公司
Priority date: 2015-11-09
Filing date: 2016-08-01
Publication date: 2017-05-18
Also published as: CN106686622A

Abstract

Disclosed are a method and apparatus for updating gateway information. The method comprises: when a mobility management element (MME) knows that an evolved node B (eNodeB) of a user equipment (UE) is changed, if a gateway control plane entity (GwC) has subscribed a position update report of the UE, the MME sends a session creation request message or a bearer modification request message to the GwC, the session creation request message or the bearer modification request message carrying position information of the UE; and the MME acquire a gateway user plane entity (GwU) address and a tunnel endpoint identifier (TEID) from a session creation response or a bearer modification response message returned by the GwC.

Description

Gateway information updating method and device

Technical field

The present application relates to, but is not limited to, the field of mobility management, and in particular, to a gateway information update method and apparatus.

Background technique

FIG. 1 is a schematic structural diagram of an EPS (Evolved Packet System) of 3GPP (3rd Generation Partnership Project). As shown in FIG. 1 , the 3GPP EPS includes E-UTRAN (Evolved Universal Terrestrial). Radio Access Network, evolved universal mobile communication system terrestrial radio access network), MME (Mobility Management Entity), S-GW (Serving Gateway), PDN GW or P-GW (Packet Data Network Gateway) The packet data network gateway, the HSS (Home Subscriber Server), the PCRF (Policy and Charging Rules Function), and other supporting nodes.

The MME and the E-UTRAN are connected through an S1-MME interface, and are used for control plane related operations such as mobility management, non-access stratum signaling processing, and user mobility management context management; the S-GW is passed with the E-UTRAN. The access gateway device connected to the S1-U interface forwards data between the E-UTRAN and the P-GW, and is used to buffer the paging waiting data; the P-GW is the EPS and PDN (Packet Data Network Gateway, packet) A border gateway for data networks, for PDN access and forwarding of data between EPS and PDN. The PCRF is responsible for the formulation of policy decisions and charging rules, and the operator's IP services (interacting with the operator's IP service entity), providing service data flow-based gating, quality of service control, and charging rules to the GW (Gateway, Gateway). The bearer plane performs the policy and charging rules established by the PCRF. When the bearer is established, the GW performs QoS (Quality of Service) authorization and gating control according to the rules sent by the PCRF. According to the charging rule sent by the PCRF, the corresponding service data flow charging operation is performed, and the charging may be online charging or offline charging. If it is online charging, you need to work with OCS (Online Charging System) for credit management. The related charging information is exchanged between the OFCS (Offline Charging System) and the offline charging system. GW and The interface between the PCRFs is a Gx interface, the interface between the OCS and the OCS is a Gy interface, and the interface between the OFCS and the OFCS is a Gz interface.

In 3GPP, the User Equipment (UE) can find the corresponding PDN through the APN (Access Point Name), and establish an IP-CAN (IP Connectivity Access Network) for accessing the PDN network. The PDN connection for the session.

As demand grows, EPS gateways gradually create some constraints. The user data stream processing is concentrated on the PDN egress gateway, which causes the gateway device to have complicated functions and poor scalability. The control plane of the gateway is highly coupled with the forwarding plane, which is not conducive to the smooth evolution of the core network. The frequency of the forwarding surface expansion is higher than that of the control plane. The tight coupling causes the control plane to forward and expand synchronously. The short equipment update period leads to an increase in the composite cost. Network layer data forwarding is difficult to identify users and service features. It can only be forwarded according to the QoS delivered by the upper layer, resulting in inefficient use of network resources. It is difficult to finely control the data flow based on user and service characteristics. In addition, a large number of strategies require manual configuration, resulting in increased management complexity and high operating costs. Therefore, the control functions and forwarding functions in the packet domain gateway need to be further separated to meet the needs of network development and market applications.

2 is an architecture of a GW control plane and a user plane separated in a non-roaming scenario based on the present invention. The architecture splits the S-GW/P-GW in the original EPS architecture into two functional network elements: GwC (Gateway Controller, Gateway Control Entity) and GwU (Gateway User). GwC is responsible for the control plane functions of the S/P-GW, including load sharing, GwU selection, IP address and tunnel identification assignment, policy and charging control. The GwU includes the SGwU (Serving Gateway User) and the PGwU (Packet Data Network Gateway User), which respectively correspond to the user planes of the S-GW and the P-GW, and is responsible for the user plane of the S/P-GW. Related functions include data flow identification and deep packet parsing, QoS processing and bearer binding, and buffering of downstream paging data. The user plane and control plane interface of the docking correspond to GwC and SGwU/PGwU respectively, and the other corresponding interface functions are compared with the original EPS architecture.

After the GW control plane and the user plane are separated, many problems of the related art EPS gateway are solved, but new technical problems are also introduced. For example, the switching mechanism that causes the related art cannot support the correct and reliable transmission of the data stream in some scenarios.

Summary of the invention

The following is an overview of the topics detailed in this document. This Summary is not intended to limit the scope of the claims.

In the related art mechanism, the MME performs selection of the S-GW based on the user location and the contract information. When the location of the UE moves to initiate the handover and tracking area update procedure, the MME determines whether the S-GW needs to be reselected, and performs S-GW selection and information update of the uplink and downlink data transmission paths. If it is determined that the S-GW needs to be reselected, the appropriate S-GW is reselected according to the updated location information and the subscription information, and the newly selected S-GW uplink user plane address and tunnel identifier are sent to the eNodeB ( Evolved Node B, the evolved Node B), updates the uplink data transmission path information to ensure the correct transmission of the uplink data. The new eNodeB information, for example, the eNodeB downlink user plane address and the tunnel identifier are sent to the S-GW, and the downlink data transmission path information is updated to ensure the correct transmission of the downlink data. If the reselection of the S-GW is not required, the information such as the current user plane address and the tunnel identifier of the current S-GW is sent to the new eNodeB, and the new eNodeB downlink user plane address and the tunnel identifier are transmitted to the current The S-GW performs reconstruction of the uplink and downlink data channels.

After the S-GW control and the user plane function are separated, the GW selection by the MME according to the existing mechanism is actually the selection of the GwC, and the GwC is responsible for selecting and managing the GwU in its corresponding GwU group. According to the mechanism described above, the data cannot be correctly forwarded in a scenario where the GwC does not need to be switched but the GwU is reselected. For example, the switching process based on the S1 interface. After the MME receives the handover request message of the original eNodeB, the MME determines that the GwC does not need to be changed, and the current GwU address and the tunnel identifier are sent to the new eNodeB, and the new eNodeB does not necessarily obtain the final GwU address and Tunnel ID. If GwU is reselected, the upstream and downstream data channels are set up incorrectly. If the uplink data arrives at the eNodeB, it will be transmitted to the old GwU. This may result in the failure to connect to the GwU or the GwU to be discarded after it is received. Business continuity and data integrity cannot be guaranteed.

Therefore, after the GW control plane and the user plane are separated, the related technology switching mechanism cannot support the correct and reliable transmission of the data stream in some scenarios, and the continuity and integrity of the service cannot be guaranteed.

This paper provides a method and apparatus for correct and reliable uplink data flow in a GW control plane and a user plane separation architecture.

A method for updating gateway information includes:

The mobile management unit MME sends a create session request or a modify bearer request message to the GwC if the gateway control plane entity GwC has subscribed to the location update report of the UE when the evolved Node B eNodeB of the user equipment UE is changed. The location information of the UE is carried in the create session request or the modify bearer request message;

The MME obtains a gateway user plane entity GwU address and a tunnel endpoint identifier TEID from the Create Session Response or Modify Bearer Response message returned by the GwC.

Optionally, the location information includes a tracking area identifier TAI and user location information ECGI.

Optionally, the manner in which the MME learns that the eNodeB of the UE is changed includes receiving any one or any of the following messages:

Attach request, tracking area update request, service request, handover request, forward relocation request.

Optionally, the method further includes:

In the process flow that the UE is attached to the network, the MME receives the create session response message sent by the GwC, and learns, according to the create session response message, whether the GwC subscribes to the location update report of the UE.

Optionally, the obtaining, according to the creating a session response message, whether the GwC subscribes to the UE location update report includes:

When the MME carries the user location update action in the create session response message, it is learned that the GwC subscribes to the location update report of the UE to the MME.

Optionally, after the MME obtains the GwU address and the tunnel endpoint identifier TEID from the Create Session Response or the Modify Bearer Response message returned by the GwC, the MME further includes:

If the MME does not send the GwU address and the TEID to the changed eNodeB, the MME transmits the acquired GwU address and the TEID to the changed eNodeB.

If the MME has sent the GwU address and the TEID to the changed eNodeB, it is determined whether the acquired GwU address and the TEID are the same as those sent to the changed eNodeB, and if not, the acquired GwU address and TEID are sent. Give the changed eNodeB.

Optionally, the method further includes:

The MME, in the handover request or the initial context request of the changed eNodeB, carries a pending transaction indication, where the pending transaction indication is used to notify the changed eNodeB to receive the GwU address and the TEID again, or to confirm that the GwU is not Before the change, the data that is uplinked to GwU and the downlink forwarding data are cached.

A gateway information updating device, configured in the mobility management unit MME, includes:

a requesting module, configured to: when the evolved Node B eNodeB of the user equipment UE is changed, if the gateway control plane entity GwC has subscribed to the location update report of the UE, send a create session request or modify a bearer request message to the GwC Carrying the location information of the UE in the create session request or modify bearer request message;

The obtaining module is configured to: obtain a gateway user plane entity GwU address and a tunnel endpoint identifier TEID from the create session response or modify bearer response message returned by the GwC.

Optionally, the manner in which the requesting module learns that the eNodeB of the UE changes includes receiving any one or any of the following messages:

Optionally, the device further includes:

The receiving module is configured to: in the process flow that the UE is attached to the network, receive a create session response message sent by the GwC, and learn, according to the create session response message, whether the GwC subscribes to the location update report of the UE.

Optionally, the receiving module is configured to:

When the user session update action is carried in the create session response message, the GwC is notified to subscribe to the location update report of the UE.

Optionally, the device further includes:

The first sending module is configured to: when the GwU address and the TEID are not sent to the changed eNodeB, send the GwU address and the TEID acquired by the acquiring module to the changed eNodeB.

Optionally, the device further includes:

The second sending module is configured to: when the GwU address and the TEID have been sent to the changed eNodeB, determine whether the acquired GwU address and the TEID are the same as those sent to the changed eNodeB, and if they are different, send the obtained The GwU address and the TEID are given to the changed eNodeB.

Optionally, the sending module is further configured to: in the handover request or the initial context request of the changed eNodeB, carry a pending transaction indication, where the pending transaction indication is used to notify the changed eNodeB to receive again The GwU address and the TEID are encrypted, and the data that is uplinked to the GwU and the downlink forwarding data are buffered before the GwU is confirmed to be unchanged.

A computer readable storage medium storing computer executable instructions that, when executed by a processor, implement the above method.

In the embodiment of the present invention, when the GW control plane and the user plane are separated, the MME can learn the correct GwU address and the tunnel endpoint identifier, and further inform the eNodeB, so as to ensure that the uplink data stream can be correctly and reliably transmitted when the GwU is changed. .

Other aspects will be apparent upon reading and understanding the drawings and detailed description.

BRIEF abstract

1 is a schematic structural diagram of an evolved packet system of 3GPP;

2 is a schematic structural diagram of separating a GW control plane from a user plane in a non-roaming scenario;

3 is a schematic flowchart of a gateway information update method according to Embodiment 1;

4 is a schematic diagram of a GwC subscription location change event report in an attach process;

FIG. 5 is a schematic diagram of establishing a correct uplink data channel in a handover process based on an S1 interface;

Figure 6 is a schematic diagram of establishing a correct uplink data channel in a service request process;

FIG. 7 is a schematic diagram of a gateway information updating apparatus of Embodiment 2.

Embodiments of the invention

Embodiments of the present invention will be described below with reference to the drawings and embodiments.

It should be noted that, if not conflicting, the features of the embodiments of the present invention and the embodiments may be combined with each other, and are all within the protection scope of the present application. Additionally, although logical sequences are shown in the flowcharts, in some cases the steps shown or described may be performed in a different order than the ones described herein.

Embodiment 1 A method for updating gateway information, as shown in FIG. 3, includes steps S110-S120:

S110. When the MME is informed that the eNodeB of the UE is changed, if the GwC has subscribed to the location update report of the UE, send a create session request or modify a bearer request message to the GwC, in the create session request or modify the bearer request message. Carrying location information of the UE. The location information may include, but is not limited to, at least a TAI (Tracking Area Identity) and an ECGI (User Location Information).

S120. The MME obtains a GwU address and a TEID (Tunnel Endpoint Identifier) from the Create Session Response or the Modify Bearer Response message returned by the GwC. The TEID may be one or more.

In this embodiment, the user location update includes at least an eNodeB change.

In this embodiment, the GwC address and the TEID carried in the GwC in the Create Session Response or the Modify Bearer Response message are the current correct GwU address and the TEID; the GwC may determine whether to perform the GwU reselection according to the location information, if not The reselection returns the original GwU address and TEID. If you want to reselect, GwU is selected and the changed GwU address and TEID are returned.

Optionally, the manner in which the MME learns that the eNodeB of the UE is changed may include, but is not limited to, receiving any one or any of the following messages: an attach request, a tracking area update request, a service request, a handover request, and a forward transfer weight. Location request.

Optionally, the method further includes:

In this optional mode, the create session response message indicates that the GwC subscribes to the bit of the UE. The manner of updating the report may be, but is not limited to, the GwC carrying a user location update action in the create session response message. The obtaining, according to the creating a session response message, whether the GwC subscribes to the location update report of the UE may include: when the MME sends a user location update action, the MME learns that the GwC is sent to the MME. Subscribe to the location update report of the UE (ie, the event escalation of the user location update subscribed to the UE).

Optionally, after the step S120, the method may further include:

It can be seen that if the GwU is changed, the GwU address and the TEID sent in the alternative are the changed GwU address and the TEID.

Optionally, after the step S120, the method may further include:

In this alternative, after the MME learns that the eNodeB is switched, the GW sends the GwU address and the TEID to the changed eNodeB according to the existing procedure; and then sends the location information to the GwC; if the MME finds the GwU address and the TEID returned by the GwC, If the eNodeB is sent to the changed eNodeB, the MME sends the GwU address and the TEID to the changed eNodeB again; if they are the same, they can no longer send; in other alternatives, they can also be configured to send the acquired whether they are the same or not. The GwU address and TEID are given to the changed eNodeB.

In this alternative, the method may further include:

The MME, in the handover request or the initial context request of the changed eNodeB, carries a Pending Transaction, where the Pending Transaction is used to notify the changed eNodeB to receive the GwU address and the TEID again, or It is confirmed that the data that is uplinked to GwU and the downlink forwarding data are buffered before the GwU is changed.

In this alternative, the Pending Transaction is equivalent to notifying the changed eNodeB to wait for the GwU to reselect. If the GwU address and the TEID sent by the MME are received again, the GwU reselection is confirmed, and the MME resends. GwU address and TEID instead of MME The GwU address and the TEID sent for the first time are used for the transmission of the uplink data. If the eNodeB does not receive the GwU address and the TEID sent by the MME again within the predetermined time period, the GwU does not change, and the GwU address and TEID sent by the MME for the first time are used. Perform uplink data transmission.

In this alternative, the eNodeB adds a cache function. The eNodeB buffers the data that is uplinked to the GwU and the data that is forwarded after receiving the GwU address and the TEID again, or confirming that the GwU is not changed.

In other alternatives, the following schemes can also be adopted:

After the MME learns that the eNodeB is switched, the GW sends the GwU address and the TEID to the changed eNodeB according to the existing procedure; and then sends the location information to the GwC; the GwU address and the TEID acquired from the GwC are sent to the changed eNodeB. Whether the same is the same, the acquired GwU address and TEID are sent again to the changed eNodeB;

The Pending Transaction is configured to notify the changed eNodeB to cache the data that is uplinked to the GwU and the downlink forwarding data before receiving the GwU address and the TEID again;

The changed eNodeB buffers the data that is uplinked to the GwU and the data that is forwarded, until the GwU address and the TEID are received from the MME for the second time, and the GwU address and the TEID received for the second time are used for uplink data transmission.

Implementation example one

Process flow (1)

In the process of the UE attaching to the network, when the GwC sends a create session response message to the MME, the message carries a user location update action, and is used for the GwC to subscribe to the MME for the event report of the user location update. The UE location update includes at least a change of the eNodeB. If the default user location update action is created in the session response message, the MME does not trigger the sending of the location update report of the UE to the GwC when the eNodeB of the UE is changed (ie, sending a session request to carry the location information of the UE) Or modify the bearer request message). As shown in FIG. 4, the processing flow (1) includes the following steps:

Step 301: The UE initiates an attach operation to the EPS network, and the network completes the authentication and authorization for the UE. As described in 301-1 to 301-6:

301-1. The UE sends an attach request message to the eNodeB, where the message includes: the user identifier, the last visited tracking area, the core network capability of the UE, the attachment type, the NAS (Non-access stratum) serial number, and the PDN. Type and other information.

301-2. The eNodeB selects an MME according to an RRC (Radio Resource Control) parameter and a selected network, or an MME selection function. The eNodeB then forwards the attach message to the new MME along with the TAI and ECGI identity of the cell in which the UE is located.

301-3. If the MME changes since the UE was last attached, the current new MME obtains the old MME address, and sends an identity request message to the old MME to request the IMSI (International Mobile Subscriber Identification Number). Code) and mobility context.

301-4. If the UE cannot be identified in both the new and old MMEs, the new MME sends an identity request message to the UE to request the IMSI. The UE notifies the network using an identity response message containing the IMSI.

301-5a. If no UE context exists in the network, or if the attach request message does not have integrity protection or encryption, or if the integrity check fails, the authentication process and the NAS security up and down establishment process must be performed. If the UE context exists in the network and the attachment request message is integrity protected or encrypted, the integrity check is successful. This step is optional. If the NAS security algorithm changes, this step only performs the NAS security context establishment process. The authentication and NAS security context establishment process is performed as defined in the Security Features section. After this step, all NAS messages will be protected by the NAS security function indicated by the MME.

301-5b. Obtain a mobile device identifier IMEI from the UE. The IMEI logo must be transmitted in encrypted form, except in the case of emergency attachment and cannot be authenticated. In order to minimize the delay of signaling, the mobile device identity acquisition may be incorporated in the NAS security context establishment process of step 301-5a. The MME sends a mobile device identity detection request to the EIR (Equipment Identity Register), and the EIR responds with the detected result by the mobile device identity detection response message. The MME determines whether to continue the attach procedure or reject the UE according to the result.

301-6. If the UE sets an encryption option transmission flag in the attach request message, this step may obtain an encryption option from the UE.

Step 302: The MME selects a GW according to an existing EPC network, and performs gateway selection. Alternatively, obtain the IP addresses of the SGW and PGW control planes. Whether the gateway type is the SGW or the GW separated from the control plane and the user plane has no effect on the GW selection of the MME. In this example, the GW type is a GW where the control plane and the user plane are separated, where the SGW control plane IP address is the IP address of the GwC.

Steps 303-306 are optional steps. If there is old context information in the network (for example, an active bearer context exists in the MME), the MME deletes the old bearer context information in the GW by deleting the session request procedure.

Step 303: The MME sends a Delete Session Request message to the GwC.

Step 304: The GwC initiates an IP-CAN session termination operation to the PCRF.

Step 305: The GwC sends a delete flow table request to the SGWU and the PGWU.

Step 306: The GwC replies to the MME with a Delete Session Response message.

Step 307: The MME sends a Create Session Request message of the S1-MME interface to the GwC, and carries the user identifier, the APN identifier, the MME control plane TEID, the GwC address, the PGW address, the PDN address, the bearer identifier, the handover indication, and the like. . The handover indication indicates whether the current attachment is an initial attachment or a handover attachment. The GwC has different operations in the subsequent steps according to the indication. For details, refer to the subsequent steps. The PGW address is the address of the GwC (when the GW is set) or the address of the selected P-GW (when the GW is set).

Step 308: The GwC selects the correct GwU according to the gateway selection function, that is, selects the GwU that performs the forwarding function as the SGWU and the PGWU. The TEID is assigned to the GwU, including the default bearer TEID of the PGWU, and the UL (Uplink, uplink) and DL (Downlink) TEID of the SGWU. The GwC assigns an IP address to the PDN connection of the UE or acquires an IP address from the external PDN.

Step 309: When the PCRF is deployed and the session request message is created, the handover indication does not exist, and the GwC performs an IP-CAN session establishment process to obtain a default PCC (Policy and Charging Control) criterion of the UE. If there is a handover indication, the GwC performs an IP-CAN session modification procedure. The IP-CAN session establishment or modification operation on the Gx interface is initiated to the PCRF to trigger the establishment of the relevant bearer. If no dynamic PCC is deployed, GwC adopts a local QoS policy.

Step 310: The GwC sends a flow table to the SGWU, including: an IP address of the PGWU, a TEID, and the like.

Step 311: The GwC sends a flow table to the PGWU, including: an IP address of the SGWU, a TEID, a meter, and other statistics.

Step 312: The GwC responds to the Create Session Response message to the MME. Contains the IP address of the SGWU, the user plane TEID, the control plane TEID, the IP address of the PGWU, and the TEID. And the message carries the user location update action, and is used by the GwC to subscribe to the MME to update the event of the user location update. The user location update includes at least a change of the eNodeB. If the default user location update action in the session response message is created, the MME does not trigger the sending of the location update report to the GwC when the UE senses that the UE location changes. The message also carries related parameters defined by other EPS network S1-MME interfaces. If the GwC subscribes to the user location update report, the MME will send the location information of the UE to the GwC for the GwC to decide whether to perform the GwU reselection.

Step 313: The access network signaling interaction and the air interface bearer establishment. The eNodeB sends an RRC Connection Reconfiguration message to the UE, which includes an EPS RB (Resource Block) ID and an Attach Accept message. The UE sends an RRC Connection Reconfiguration Complete message to the eNodeB. The eNodeB sends an Initial Context Response message to the new MME. The message contains the TEID of the eNode B and the address of the eNodeB for the downlink data transmission of the S1-U interface. The UE sends a Direct Transfer message to the eNodeB, which contains an Attach Complete message. The eNodeB forwards the Attach Complete message to the new MME using the uplink NAS transport message.

Step 314: The MME sends the user plane address and the TEID of the eNodeB to the GW through the Modify Bearer Request message (in this example, to the GwC).

Step 315: The GwC updates the flow table to the SGwU, and sends the user plane address and the TEID of the eNodeB to the SGwU. After the downlink data channel is completed, data can be sent to the UE.

Step 316: If the connection scenario is switched, the GwC updates the flow table to the PGwU, and notifies the GwUPGwU to send data from the network side.

Step 317: The GwC replies to the MME with a Modify Bearer Response. Message.

Process flow (2)

The following is a process of initiating a handover between eNodeBs based on the S1 interface when the source eNodeB and the target eNodeB are not connected to the X2 interface. After receiving the handover request message, the MME detects that the location of the UE has changed, that is, the eNodeB of the UE has been handed over, and the GW subscribes to the location update report of the UE, and the MME sends a create session request or a modify bearer request message, where Carry location information to GWC. The location information includes at least a TAI and an ECGI. The GWC determines whether the GwU needs to be reselected and executed according to the location information provided by the MME, and returns a create session response or a modify bearer response message to the MME, and returns the correct GWU address and TEID information to the MME, and the MME sends the information to the eNodeB to establish the correct The upstream data transmission channel. The manner in which the MME perceives the eNodeB change includes: receiving an attach request, or receiving a tracking area update request, or receiving a service request, or receiving a handover request, or receiving a forward relocation request. Here, an example of a scenario in which a handover request is received or a forward relocation request is received is described. As shown in FIG. 5, the processing flow (2) includes the following steps:

Step 401: The source eNodeB sends a Handover Required to the source MME (if the MME changes). The handover request message carries a source-to-target transparent container, a target (target) eNodeB ID (Identity), a target TAI, and directly forwards the tag. A list of bearers performing data forwarding is indicated in the transparent container. The purpose of the TAI is to facilitate the selection of a suitable target MME.

Step 402: If the MME changes, the source MME selects the target MME, and sends a Forward Relocation Request message to the target MME, where the message includes the MME user context, the source to the target transparent container, and the target eNodeB identifier. Target tracking area identification and other information. The target TAI is used by the MME to determine whether SGW/GwC reselection is to be performed. The MME user context may further include: a GW type identifier or a control plane user plane separation identifier, indicating that the GW type is a GW (the MME and the GwC interaction) separated by the user plane control plane or the GW of the user plane control plane is unified (the MME and the MME) S-GW interaction).

Step 403: The MME determines whether S-GW/GwC reselection is to be performed (whether the source S-GW can continue to serve the UE), and if necessary, selects a new S-GW/GwC. If the MME does not relocate Then, the source MME determines whether to perform reselection of the S-GW/GwC and selects when it is to be reselected. Otherwise, the destination MME determines whether to perform reselection of the S-GW/GwC and selects when the reselection is to be performed. In this example, the GW is separated by the user plane control plane, and the MME determines whether to perform GwC reselection and select a new GwC when needed.

After receiving the handover request message, the MME confirms that the eNodeB has changed (determined according to the eNodeB ID), and the GwC subscribes to the location update report of the UE, and the MME sends a create session request or a modify bearer request message to the GWC, and carries the location information to the GW. GwC, including TAI, ECGI (including eNodeB ID), Serving Network (service network) and other location information. The GWC performs judgment and execution of GwU reselection.

Step 403a. Optionally, if the GwU reselection is performed, and the GwU user plane address and the TEID are allocated by the GwU, the GwC sends a routing information update request to acquire a new GwU user plane address and TEID.

Step 404: The GwC determines whether to perform the GwU reselection according to the location information in the create session request or the modify bearer request message, and the GwU selection function, and if necessary, perform the GwU selection. The GwU user plane address and TEID for the uplink data transmission of the S1-U interface are allocated for the GwU. The GwC sends a create session response or a modify bearer response message to the target MME, carrying the allocated GwU address and the user faceted TEID. If the GwU is reselected, the GwU address is the new GwU address after the reselection.

Step 405: The target MME sends a Handover Request message to the target eNodeB, and creates a UE context on the target eNodeB, including bearer information and a security context. The message carries the GwU address and the uplink TEID and EPS bearer QoS for the user plane allocated for each EPS bearer.

Step 406: The target eNodeB sends a Handover Request Acknowledge message to the target MME, where the message includes the address and TEID allocated by the target eNodeB for the uplink and downlink packets of the S1-U interface, and the address and TEID allocated for receiving the forwarding data.

Step 407: If the MME changes, the target MME sends a forward relocation response message to the source MME, where the message carries the address and TEID allocated by the eNodeB for receiving and forwarding data, and the message is forwardly forwarded, and the message includes the GwU forwarding address forwarded indirectly. And TEID.

Step 408: Indirect forwarding, the target MME sends a Create Indirect Data Forwarding Tunnel Request message to the GwC, where the message carries the target eNodeB user plane address and TEID for data forwarding.

Step 409: The GwC sends a routing information update message to the SGWU, and carries the IP address and TEID information of the target eNodeB used for data forwarding.

Step 409a: The GwC sends a routing information update message to the PGWU, and carries the IP address and TEID information of the target eNodeB for data forwarding.

Step 410: The GwC sends a Create Indirect Data Forwarding Tunnel Response message to the target MME, where the message carries the address and TEID used by the GwU to forward the uplink data of the S1-U interface. If the GwC is not relocated, the MME is the source MME.

Steps 411-415 perform an air interface switching operation and an indirect forwarding process of the data packet:

Step 411: The source MME sends a Handover Command message to the source eNodeB, where the message carries the address and TEID used by the GwU for data forwarding. The source eNodeB constructs a Handover Command message to the UE using a Target to Source transparent container.

Step 412: The source eNodeB starts to forward downlink data from the source eNodeB through the GwU to the target eNodeB.

Step 413: After successfully synchronizing to the target cell, the UE sends a Handover Confirm message to the target eNodeB. The downlink forwarding data from the source eNodeB is transmitted to the UE, and the uplink data is transmitted by the target eNodeB to the GwU.

Step 414: The target eNodeB sends a Handover Notify message to the target MME, where the message carries the TAI and the ECGI.

Step 415: If the target MME is relocated, the target MME sends a Forward Relocation Complete message to the source MME.

In step 415a, in response, the source MME may send a Forward Relocation Complete Acknowledge message to the target MME.

Step 416: The target MME sends a Modify Bearer Request message to the GwC, and carries the user plane address and the TEID of the target eNodeB. Optionally, the MME may also carry the Location information of the UE.

Step 417: If the user location information is reported in step 416, and the PCRF signs the event information, the GwC initiates an IP-CAN session modification operation with the PCRF, and reports the event information.

Step 418: The GwC sends a routing information update message to the SGwU, and carries the IP address and TEID information of the target eNodeB.

Step 418a: The GwC sends a routing information update message to the PGwU, carrying the IP address and TEID information of the target eNodeB.

Step 419: The GwC sends a Modify Bearer Response message to the target MME. The GwC sends one or more "end marker" packets on the old path immediately after the path conversion to assist the target eNodeB in performing the reordering function.

Step 420: The downlink data runs through, and the source network side radio resource is released.

Step 421: The source MME sends a Delete Indirect Data Forwarding Tunnel Request message to the GwC to release the temporary resource allocated for indirect forwarding.

Step 422: The GwC sends a flow table update request to the SGwU, and deletes the flow table information used for data forwarding.

Step 423: The GwC returns a delete forward data channel request response message to the source MME.

Process flow (3)

The following is a service request procedure, that is, a process in which the UE establishes a signaling connection for the transmission of the upper layer signaling or the reserved resource of the active bearer in the IDLE state. After receiving the service request message, the MME detects that the location of the UE has changed, that is, the eNodeB has switched. If the GwC subscribes to the location update report, the MME sends a create session request or a modify bearer request message to the GW, where the location information is carried. The location information includes at least a TAI and an ECGI. Based on the location information provided by the MME, the GwC determines whether the GwU needs to be reselected and executed. The MME returns a Create Session Response message or a Modify Bearer Response message, and returns the correct GwU address and the tunnel identifier TEIDs information to the MME, and the MME transmits the information to the eNodeB to establish a correct uplink data transmission channel. The manner in which the MME perceives that the eNodeB changes includes: receiving an attach request, or receiving Received a tracking area update request, or received a service request, or received a handover request, or received a forward relocation request. Here, an example of a scenario in which a service request is received is described. As shown in FIG. 6, the process flow (3) includes the following steps:

Step 501: The UE sends a Service Request message to the MME by using the NAS message encapsulated in the RRC message. The message is forwarded to the MME by the eNodeB, and the message is encapsulated in an Initial UE Message of the S1-AP type. The initial UE message carries the user identifier and user location related information, including the TAI and the ECGI.

Step 502: The NAS authentication and security activation process may be performed according to the needs of the network.

Step 503: After receiving the service request message, the MME confirms that the eNodeB has changed (determined according to the eNodeB ID), and the GwC has previously subscribed to the location update report of the UE, and the MME sends a Create Session Request to the GwC. The message includes location information such as TAI, ECGI (including eNodeB ID), Serving Network (service network). GwC performs judgment and execution of GwU reselection.

Step 503a. Optionally, if the GwU reselection is performed, and the GwU user plane address and the TEID are allocated by the GWU, the GwC sends a routing information update request to acquire a new GwU user plane address and TEID.

Step 504: The GwC determines whether to perform the GwU reselection according to the location information in the create session request message and the GwU selection function, and if necessary, performs the GwU selection. The GWU is allocated a GWU address and TEID for uplink data transmission of the S1-U interface. The GwC sends a Create Session Response message to the MME, and carries the allocated GwU address and the user-side TEID to the MME. If the GwU is reselected, the GwU address is the new GwU address after the reselection.

Step 505: The MME sends an S1-AP type message Initial Context Setup Request to the eNodeB, where the message carries the GwU address and the TEID on the user plane, and carries information such as QoS, security context, and MME signaling connection identifier.

Step 506: The eNodeB performs a radio bearer setup process according to the received GwU address, the TEID on the user plane, and the bearer QoS. And establish a user plane security context. When the user plane radio bearer setup and service request are completed and the EPS bearer status is synchronized between the UE and the MME After that, the UE will delete the EPS bearer without the radio bearer. If a radio bearer of a default EPS bearer is not established, the UE locally deactivates all EPS bearers associated with this default bearer.

Step 507: The uplink data of the UE is forwarded to the GwU through the eNodeB. The eNodeB sends the uplink data to the GwU address and TEID provided in step 505. SGwU forwards the upstream data to PGwU.

Step 508: The eNodeB sends an S1-AP type message Initial Context Setup Complete to the MME, where the message carries an eNodeB user plane address and TEID for downlink data transmission, and other bearer related information.

Step 509: The MME sends a Modify Bearer Request message to the GwC, where the message carries the eNodeB user plane address and TEID for downlink data transmission, and other bearer related information.

Step 510: The GwC sends a flow table to the SGWU, and updates routing information, where the user plane IP address and TEID information of the eNodeB are included.

Step 510a: The GwC sends a flow table to the PGWU, and updates routing information, where the user plane IP address and TEID information of the eNodeB are included. At this point, the downlink data channel is established, and the GwU can send downlink data to the UE through the channel.

Step 511: The GwC responds to the MME with a Modify Bearer Response message.

Figure 5 and Figure 6 show that the MME sends a Create Session Request or Modify Bearer Request to notify the GwC location change in the S1 interface-based handover process or the service request process, obtains the correct GwU address and tunnel identifier, and provides it to the eNodeB to establish the correct uplink. Schematic diagram of the data channel.

Process flow (4)

In the scenario of process flow (2), the corresponding implementation manner may also be:

After receiving the handover request message, the MME detects that the location of the UE has changed, that is, the eNodeB has switched, and the GwC subscribes to the location update report, and the MME does not immediately perform steps 403-404 in the process flow (2), namely: The process of processing the correct GwU address and the TEID is obtained by creating a session request or modifying the bearer request message to carry the location information to the GwC. In the process, the MME first performs an existing service request process, and sends the currently stored GwU address and TEID to the changed eNodeB, and sends a Pending Transaction to the changed eNodeB; until step 416, the MME further modifies The bearer request message carries the eNodeB address and the TEID.

The GwC carries the final GwU address and TEID to the MME in the modify bearer response message in step 419. The MME compares the GwU information. If the GwU is changed, the MME changes the bearer modification process to the eNodeB, and delivers the final GwU address and TEID to the eNodeB.

The eNodeB first caches the data, and after receiving the updated GwU address and TEID, completes the bearer modification process and updates the GwU information. And the transmission of the cached data is completed; or the updated GwU address and the TEID are not received within the predetermined time period, and it is confirmed that the GwU is not changed, and the original bearer is used to transmit the cached data.

Optionally, in the process flow (4), the eNodeB needs to add a cache function. The data that is uplinked to GwU and the data that is forwarded are buffered before the updated GwU address and TEID are received, or before the GwU is confirmed to be unchanged.

Optionally, in the handover request of step 405, the MME carries a Pending Transaction to the eNodeB, and informs that there may be a reselection and information update of the GwU (ie, receiving the GwU address and the TEID again). It is convenient for the eNodeB to cache the uplink data to the GwU and the downlink forwarding data when the data transmission fails. The cache time period and mode depend on the actual product implementation, which is not limited here.

Process flow (4) The rest of the detailed process is handled in the same way as in (2), and no repeated description is made.

Process flow (5)

In the scenario of process flow (3), the corresponding implementation manner may also be:

When the MME detects that the location of the UE has changed, that is, the eNodeB has switched, and the GwC subscribes to the location update report of the UE, the MME does not immediately perform steps 503-504 in the process flow (3), that is, The process of creating a session request or modifying a bearer request message carries the location information to the GwC to obtain the correct GwU address and TEID. In this process, the MME first performs the existing handover process, and sends the currently stored GwU address and TEID to the change. The eNodeB is sent, and the Pending Transaction is sent to the changed eNodeB. Until step 509, the MME carries the eNodeB address and the TEID in the modify bearer request message.

The GwC carries the final GwU address and the TEID to the MME in the modify bearer response message in step 511. The MME compares the GwU information. If the GwU is changed, the MME changes the bearer modification process to the eNodeB, and delivers the final GwU address and TEID to the eNodeB.

Optionally, in process flow (5), the eNodeB needs to add a new cache function. The data that is uplinked to GwU and the data that is forwarded are buffered before the updated GwU address and TEID are received, or before the GwU is confirmed to be unchanged.

Optionally, the MME sends a Pending Transaction to the eNodeB in the initial context request of the eNodeB in step 505, and informs that there may be a GwU reselection and information update (ie, receiving the GwU address and the TEID again). It is convenient for the eNodeB to cache the uplink data to the GwU and the downlink forwarding data when the data transmission fails. The cache time period and mode depend on the actual product implementation, which is not limited here.

Process flow (5) The rest of the detailed process is processed in the same way as in (3), and no repeated description is made.

As described above, the processing flows (1) and (2), the processing flows (1) and (3), the processing flows (1) and (4), and the processing flows (1) and (5) constitute the two scenarios respectively. The four processing flows of the two embodiments. A method for supporting correct and reliable data flow transmission in a scenario where the user location changes in the GW control plane and the user plane separation architecture is described in detail. The method is also applicable to other scene processing of UE location change. And the processing of data transmission in a communication architecture where control and user plane functions are separated. The method is also applicable to the GW control plane that is required to perform the GWU reselection, or the GWC is required to perform the GWU reselection in the GW, and the GW sends the new GWUID and the address to the eNodeB through the MME, thereby ensuring that The processing of the uplink data stream can be correctly and reliably transmitted when the GwU is changed.

Embodiment 2: A device for updating gateway information, which is set in the MME, as shown in FIG. 7, includes:

The requesting module 71 is configured to: when the evolved Node B eNodeB of the user equipment UE is changed, if the gateway control plane entity GwC has subscribed to the location update report of the UE, send a create session request or modify a bearer request message to the The GwC carries the location information of the UE in the create session request or the modify bearer request message;

The obtaining module 72 is configured to: obtain a gateway user plane entity GwU address and a tunnel endpoint identifier TEID from the create session response or modify bearer response message returned by the GwC.

Optionally, the device further includes:

In this optional mode, the receiving module is configured to:

Optionally, the device further includes:

The second sending module is configured to: when the GwU address and the TEID have been sent to the changed eNodeB, determine the acquired GwU address and TEID and send the modified eNodeB to the eNodeB. Whether the same is the same, if different, the acquired GwU address and TEID are sent to the changed eNodeB.

In this optional mode, the sending module may be further configured to: in the handover request or the initial context request of the changed eNodeB, carry a pending transaction indication, where the pending transaction indication is used to notify the changed eNodeB to After receiving the GwU address and the TEID, or confirming that the GwU is not changed, the data that is uplinked to the GwU and the downlink forwarding data are buffered.

The embodiment of the invention further provides a computer readable storage medium storing computer executable instructions, which are implemented by the processor to implement the above gateway information update method.

One of ordinary skill in the art will appreciate that all or a portion of the steps described above can be accomplished by a program that instructs the associated hardware, such as a read-only memory, a magnetic or optical disk, and the like. Alternatively, all or part of the steps of the above embodiments may also be implemented using one or more integrated circuits. Correspondingly, the modules/units in the foregoing embodiments may be implemented in the form of hardware or in the form of software functional modules. Embodiments of the invention are not limited to any specific form of combination of hardware and software.

The embodiments disclosed in the present application are as described above, but the description is only for the purpose of understanding the present application, and is not intended to limit the present application. Any modifications and changes in the form and details of the embodiments may be made by those skilled in the art without departing from the spirit and scope of the disclosure. The scope defined by the appended claims shall prevail.

Industrial applicability

Claims

A method for updating gateway information includes:

The mobile management unit MME sends a create session request or a modify bearer request message to the GwC if the gateway control plane entity GwC has subscribed to the location update report of the UE when the evolved Node B eNodeB of the user equipment UE is changed. The location information of the UE is carried in the create session request or the modify bearer request message;

The MME obtains a gateway user plane entity GwU address and a tunnel endpoint identifier TEID from the Create Session Response or Modify Bearer Response message returned by the GwC.
The method of claim 1 wherein:

The location information includes a tracking area identifier TAI and user location information ECGI.
The method of claim 1, wherein the manner in which the MME learns that the eNodeB of the UE changes comprises receiving any one or any of the following messages:

Attach request, tracking area update request, service request, handover request, forward relocation request.
The method of claim 1 further comprising:

In the process flow that the UE is attached to the network, the MME receives the create session response message sent by the GwC, and learns, according to the create session response message, whether the GwC subscribes to the location update report of the UE.
The method of claim 4, wherein the obtaining, according to the create session response message, whether the GwC subscribes to the UE location update report comprises:

When the MME carries the user location update action in the create session response message, it is learned that the GwC subscribes to the location update report of the UE to the MME.
The method according to any one of claims 1 to 5, further comprising: after obtaining the GwU address and the tunnel endpoint identifier TEID from the Create Session Response or the Modify Bearer Response message returned by the GwC, the MME further includes:

If the MME does not send the GwU address and the TEID to the changed eNodeB, the MME transmits the acquired GwU address and the TEID to the changed eNodeB.
The method according to any of claims 1 to 5, wherein the MME is from the GwC After the obtained session response or modify bearer response message is obtained, the GwU address and the tunnel endpoint identifier TEID are also included:

If the MME has sent the GwU address and the TEID to the changed eNodeB, it is determined whether the acquired GwU address and the TEID are the same as those sent to the changed eNodeB, and if not, the acquired GwU address and TEID are sent. Give the changed eNodeB.
The method of claim 7 further comprising:

The MME, in the handover request or the initial context request of the changed eNodeB, carries a pending transaction indication, where the pending transaction indication is used to notify the changed eNodeB to receive the GwU address and the TEID again, or to confirm that the GwU is not Before the change, the data that is uplinked to GwU and the downlink forwarding data are cached.
A gateway information updating device, configured in the mobility management unit MME, includes:

a requesting module, configured to: when the evolved Node B eNodeB of the user equipment UE is changed, if the gateway control plane entity GwC has subscribed to the location update report of the UE, send a create session request or modify a bearer request message to the GwC Carrying the location information of the UE in the create session request or modify bearer request message;

The obtaining module is configured to: obtain a gateway user plane entity GwU address and a tunnel endpoint identifier TEID from the create session response or modify bearer response message returned by the GwC.
The apparatus of claim 9, wherein the manner in which the requesting module learns that the eNodeB of the UE changes comprises receiving any one or more of the following messages:

Attach request, tracking area update request, service request, handover request, forward relocation request.
The apparatus of claim 9 further comprising:

The receiving module is configured to: in the process flow that the UE is attached to the network, receive a create session response message sent by the GwC, and learn, according to the create session response message, whether the GwC subscribes to the location update report of the UE.
The device of claim 11 wherein

The receiving module is configured to: when the user session update action is carried in the create session response message, learn that the GwC subscribes to the location update report of the UE.
The apparatus of any one of claims 9 to 12, further comprising:

The first sending module is configured to: when the GwU address and the TEID are not sent to the changed eNodeB, send the GwU address and the TEID acquired by the acquiring module to the changed eNodeB.
The apparatus of any one of claims 9 to 12, further comprising:

The second sending module is configured to: when the GwU address and the TEID have been sent to the changed eNodeB, determine whether the acquired GwU address and the TEID are the same as those sent to the changed eNodeB, and if they are different, send the obtained The GwU address and the TEID are given to the changed eNodeB.
The apparatus of claim 14 wherein:

The sending module is further configured to: in the handover request or the initial context request of the changed eNodeB, carry a pending transaction indication, where the pending transaction indication is used to notify the changed eNodeB to receive the GwU address and the TEID again, Alternatively, it is confirmed that the data uplinked to the GwU and the downlink forwarding data are buffered before the GwU is changed.