CN102177748A - A network switching method, terminal, gateway and network system - Google Patents

Abstract

The embodiment of the present invention discloses a network switching method, a terminal, a gateway, and a network system. The method includes: the LTE network sends a message to the terminal to indicate that the terminal is allowed to register with the eHRPD network; when the terminal completes the eHRPD network registration through the eHRPD air interface During registration, the eHRPD network side establishes a proxy mobile IP tunnel, and the tunnel completes the handover from the terminal to the eHRPD network. The terminal includes: a registration module and a trigger module. The gateway includes: a receiving module and a tunnel establishing module. The system includes: terminal, base station and HSGW. Through the embodiment of the present invention, the handover interruption time can be shortened, and the complexity of the network and the terminal can be reduced.

Description

A kind of network switching method, terminal, gateway and network system Technical field

The present invention relates to the field of mobile communication technologies, and in particular to a network switching method, a terminal, a gateway and a network system. Background technique

LTE (Long Term Evolution, Long Term Evolution) technology is an evolution of 3GPP (Third Generation Partnership Project, Third Generation Partnership Project), which improves and enhances 3G air access technology, adopts OFDM and Multiple-input and multiple-output is the only standard for its wireless network evolution. In the LTE network, Serving Gateway (Serving Gateway) and PDN Gateway (Packet Data Network Gateway, P-GW) are evolved gateways, responsible for forwarding data packets, and MME (Mobility Management Entity, Mobility Management Entity) is a signaling control The entity is responsible for functions such as authentication and mobility management. The evolved network does not provide the voice function of traditional circuit switching, but only provides high-speed data bearer services, and the evolved network can also support interworking with the third-generation wireless data network and the second-and-fifth generation wireless data network of 3GPP.

HRPD (High Rate Packet Data, high rate packet data) is a 3GPP2 (Third Generation

The third-generation data wireless communication system defined by Partnership Project 2, 3rd Generation Partnership Project 2) does not provide voice functions of traditional circuit switching, but only provides high-speed data bearer services. In the HRPD network, an AN (Access Network, access network) entity is a network element, which is equivalent to a base station and a base station controller, and is responsible for functions such as data modulation, demodulation, and switching. The PCF (Packet Control Function) entity is responsible for data forwarding and packet data session state maintenance. eHRPD (evolved High Rate Packet Data, evolved high rate packet data) is an evolution of HRPD network for interoperability with LTE, that is, in order for HRPD network to interoperate with LTE network, it needs to evolve to eHRPD first.

When a UE (User Equipment, user equipment, also referred to as a terminal) is handed over from an LTE network to an eHRPD network, the prior art generally uses two methods to complete the handover. The first method is non-optimized handover. In the non-optimized handover network architecture, there is no interface between LTE and eHRPD wireless network. LTE and eHRPD access the unified EPC (Evolved Packet Core, Evolved Packet Core) network, and the access anchor point is PDN Gateway. When the UE switches between LTE and eHRPD, the UE performs eHRPD session negotiation, PPP (Point-to-Point Protocol, point-to-point protocol) negotiation and EAP-AKA (Extensible Authentication Protocol- Authentication and Key Agreement, extended Authentication protocol, protocol-authentication and key agreement) authentication, and then the HSGW (HRPD Serving Gateway, HRPD Serving Gateway) initiates the establishment of a proxy mobile IP tunnel to the PDN Gateway, and the PDN Gateway releases the PDN Gateway to the S-GW (Serving Gateway) Gateway, service gateway) proxy mobile IP tunnel to complete the handover from the LTE network to the eHRPD network.

The second method is optimized handover. In the optimized handover mode, two interfaces are added between the LTE network and the eHRPD network. One interface is the S101 interface between the MME and the eAN (evolved Access Network, access network), which is essentially One tunnel forwards the signaling and data between the UE and the target network, and assists the UE to pre-register on the target network or switch from the source network to the target network; the other interface is the S103 interface between the Serving Gateway and the HSGW, which is used for forwarding The data retained in the 3GPP evolved network is sent to the eHRPD network, and then sent to the UE through the eHRPD network. When the UE resides on the LTE network, pre-register through the LTE network and the S101 tunnel in advance, and perform eHRPD session negotiation, PPP negotiation, and EAP-AKA authentication with the target eHRPD network; and S101 tunnel to send a handover message to the target eHRPD, and after the target eHRPD allocates radio resources, the UE leaves LTE to access the target eHRPD, thereby greatly shortening the handover time. Optionally, the S103 tunnel can also be used to solve the problem of lossless data transmission and reduce the packet loss rate during transmission.

In the course of implementing the present invention, the inventor finds that there are at least the following shortcomings in the prior art:

In the first way, when the UE decides to initiate a handover from LTE to eHRPD, it leaves the source LTE network, and performs processes such as eHRPD session negotiation, PPP negotiation, and EAP-AKA authentication on the target eHRPD network. It takes several seconds, resulting in a long switching interruption time, which affects the user experience. Although the second method greatly reduces the service interruption time of handover from LTE to eHRPD, it needs to add two interfaces between the LTE and eHRPD networks, which increases the complexity of the network, and needs to modify the protocol stack of the UE to enable the UE to pass The LTE sends the eHRPD message, thus increasing the complexity of the UE. Contents of the invention

Embodiments of the present invention provide a network switching method, a terminal, a gateway, and a network system, which can shorten the switching time of a UE from an LTE network to an eHRPD network and reduce the complexity of the network and the UE.

Described technical scheme is as follows:

A network switching method, applied to a long-term evolution LTE network and an evolved high-rate packet data eHRPD network, including:

The LTE network side sends a message to the terminal, indicating that the terminal is allowed to register with the eHRPD network; when the terminal completes the registration with the eHRPD network through the eHRPD air interface and decides to switch to the eHRPD network, the The eHRPD network side establishes a proxy mobile IP tunnel from the high-rate packet data service gateway HSGW to the packet data network gateway P-GW, and the proxy mobile IP tunnel completes the handover of the terminal to the eHRPD network.

A terminal, comprising: a registration module, configured to perform eHRPD network registration through an evolved high-rate packet data eHRPD air interface according to an instruction of the LTE network when the terminal resides in the Long Term Evolution LTE network;

A triggering module, configured to establish an air interface connection after the registration module completes the registration and the terminal decides to switch to the eHRPD network, and trigger the eHRPD network to establish a link from the high-rate packet data service gateway HSGW to the packet data network gateway P- A proxy mobile IP tunnel of the GW, and the proxy mobile IP tunnel completes the handover of the terminal from the LTE network to the eHRPD network.

A gateway located in an evolved high-rate packet data eHRPD network, the gateway comprising:

A receiving module, configured to receive a request message sent by the terminal during the registration process of the eHRPD network;

A tunnel establishment module, configured to determine whether the content of the attachment type field carried in the request message received by the receiving module is registration, and if so, do not establish a proxy mobile IP address to the packet data network gateway P-GW during the registration process. Tunnel, when the terminal completes the registration from the LTE network to the eHRPD network and decides to switch to the eHRPD network, establishes a proxy mobile IP tunnel to the P-GW, which is completed by the proxy mobile IP tunnel Handover of the terminal to the eHRPD network.

A network system, comprising:

The terminal is configured to register the eHRPD network through the eHRPD air interface according to an instruction from the LTE network when it resides on the Long Term Evolution LTE network, establish an air interface connection with the eHRPD network, and trigger the eHRPD network to establish a high-level A proxy mobile IP tunnel from the packet data service gateway HSGW to the packet data network gateway P-GW; the base station, located in the LTE network, is used to send a message to the terminal, indicating that the terminal is allowed to register with the eHRPD network;

A high-rate packet data service gateway HSGW, located on the eHRPD network, is used when the terminal completes from the

When the LTE network registers with the eHRPD network, a proxy mobile IP tunnel to the packet data network gateway P-GW is established, and the proxy mobile IP tunnel completes the handover of the terminal from the LTE network to the eHRPD network.

In the embodiment of the present invention, before the UE decides to initiate a handover from LTE to eHRPD, the registration of the eHRPD network is performed through the eHRPD air interface in the LTE network, which greatly reduces the handover interruption time and improves the user experience. Adding interfaces between networks reduces the complexity of the network, and does not need to modify the protocol stack of the UE, which reduces the complexity of the UE. Description of drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Apparently, the drawings in the following description are only is one of the present invention For these embodiments, those of ordinary skill in the art can also obtain other drawings according to these drawings without paying creative efforts.

FIG. 1 is a structural diagram of an LTE network and an eHRPD network provided by an embodiment of the present invention;

FIG. 2 is a flowchart of a network switching method provided by an embodiment of the present invention;

FIG. 3 is a flowchart of registration in a network switching method provided by an embodiment of the present invention;

FIG. 4 is a handover flowchart in the network handover method provided by the embodiment of the present invention;

FIG. 5 is a flowchart of an air interface session keep-alive provided by an embodiment of the present invention;

FIG. 6 is a flowchart of subnet change processing provided by an embodiment of the present invention;

FIG. 7 is another handover flowchart provided by an embodiment of the present invention;

FIG. 8 is a flowchart of another network switching method provided by an embodiment of the present invention;

FIG. 9 is a schematic structural diagram of a terminal provided by an embodiment of the present invention;

FIG. 10 is a schematic structural diagram of a base station provided by an embodiment of the present invention;

FIG. 11 is a schematic diagram of a gateway structure provided by an embodiment of the present invention;

FIG. 12 is a schematic structural diagram of an eAN provided by an embodiment of the present invention;

Fig. 13 is a schematic structural diagram of a network system provided by an embodiment of the present invention. Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The technical solution provided by the embodiment of the present invention is applied to a scenario where a terminal performs handover between an LTE network and an eHRPD network, and the network architecture is shown in FIG. 1 . Above the dotted line in the figure is the LTE network, which provides services for terminal UEs through eNodeB (evolved base station), and below the dotted line is the eHRPD network, which provides services for terminal UEs through HRPD BTS (Base Transceiver Station, Base Transceiver Station).

The terminals in the embodiments of the present invention include dual-mode terminals and multi-mode terminals, for example, dual-mode terminals supporting LTE network access technology and eHRPD network access technology, and supporting HRPD access technology, CDMA2000 lx access technology and LTE access technology multi-mode terminal with access technology. Wherein, the dual-mode terminal includes a single-transmission-double-reception terminal and a dual-transmission-double-reception terminal. A single-transmission and dual-reception terminal refers to a dual-mode terminal with two receivers and one transmitter, which can receive information from two networks (different wireless access technologies) at the same time, but at a certain moment, it can only be connected to one network send information, but cannot send information on two networks at the same time interest. The dual-transmission and dual-reception terminal refers to a dual-mode terminal with two receivers and two transmitters, which can receive information from two networks at the same time, and can send information on two networks at the same time. The cost of a single-transmit and double-receive terminal is lower than that of a dual-transmit and double-receive terminal, and one transmitter consumes less power. The cost of a dual-transmit and double-receive terminal is higher than that of a single-transmit and double-receive terminal, and two transmitters consume more power.

Referring to FIG. 2, an embodiment of the present invention provides a network switching method, which may include:

201: The terminal residing in the LTE network registers with the eHRPD network through the eHRPD air interface according to the instructions of the LTE network;

Among them, the registration process includes: eHRPD session negotiation, PPP negotiation and EAP-AKA authentication and other processes; EAP-AKA is a two-way authentication protocol, which can realize mutual authentication between the terminal and the network;

202: When the terminal decides to switch to the eHRPD network, establish an air interface connection with the eHRPD network, and trigger the eHRPD network to establish a proxy mobile IP tunnel;

Among them, Mobile IP (MIP, Mobile IP) is a protocol for realizing IP mobility, and when a user moves between different IP networks, the same IP address can be guaranteed to be allocated. Proxy Mobile IP (PMIP, Proxy Mobile IP) means that a network element in the network (such as the Serving Gateway in the LTE network or the HSGW in the eHRPD network) initiates the mobile IP protocol on behalf of the terminal. It does not require the terminal to support the Mobile IP protocol, which simplifies terminal processing;

In the embodiment of the present invention, the proxy mobile IP tunnel is established between the HSGW and the P-GW;

203: ώ proxying the mobile IP tunnel to complete the handover of the terminal from the LTE network to the eHRPD network.

In the method of the embodiment of the present invention, the order of each step can be adjusted according to actual needs. In the embodiment of the present invention, before the terminal decides to initiate the handover from LTE to eHRPD, the registration of the eHRPD network is performed through the eHRPD air interface in the LTE network, which greatly reduces the handover interruption time and improves the user experience. Adding interfaces between networks reduces the complexity of the network, and does not need to modify the protocol stack of the terminal, which reduces the complexity of the terminal.

The embodiment of the present invention also provides a handover method from an LTE network to an eHRPD network, including two processes of registration and handover. Referring to FIG. 3, the handover process may include:

301: The terminal is powered on. Since the priority of the LTE network is higher than that of the eHRPD network, the terminal searches for the LTE network first. 302: After the terminal successfully searches for the LTE network, the terminal performs the registration process of the LTE network in the LTE network, that is, the initial attachment process (Initial Attach) of the LTE network. The proxy mobile IP tunnel established during the registration process is located between the S-GW and the P - between GWs.

303: After receiving the system broadcast message of the LTE network, the terminal judges whether the pre-registration field PreRegistrationAllowed in the system broadcast message is set to "allow", that is, judges whether the network side indicates that the terminal is allowed to register to the eHRPD network, if the pre-registration field is set to "Allow", the terminal searches the eHRPD network, if the pre-registration field is If it is set to "not allowed", the terminal will not search the eHRPD network.

Specifically, if the terminal is a single-transmit and dual-receive terminal, the terminal searches for the eHRPD network in the LTE idle state; if the terminal is a dual-transmit and dual-receive terminal, the terminal searches for the eHRPD network in the LTE idle state or the LTE active state.

In this embodiment, in addition to the above method of using the pre-registration field in the system broadcast message for judgment, the terminal may also use other methods for judgment, for example, adding a new field to the system broadcast message, by setting the new field "Allow" or "Not Allowed" indicates that the terminal is currently allowed to register in the eHRPD network, or indicates that the terminal is currently not allowed to register in the eHRPD network.

304: After the terminal searches for the eHRPD network, it starts the registration of the eHRPD network through the eHRPD air interface, that is, starts the initial attachment process of the eHRPD network. The registration process includes: eHRPD air interface session negotiation, PPP negotiation, and EAP-AKA authentication processes, etc. But it does not include PDN connection establishment and subsequent procedures. If the terminal is a single-transmission and dual-reception terminal, after the terminal searches for the eHRPD network, it switches to the eHRPD mode and starts registering with the eHRPD network through the eHRPD air interface; register.

305: The terminal sends a VSNCP (Vendor Specific Network Control Protocol, equipment vendor extended network control protocol) configuration request message VSNCP Config-Req to the HSGW, requesting to establish a PDN connection, and the Attach Type (Attach Type) field in the configuration request message is set to "Registration Only", for example, setting the value of this field to 255 represents "registration", and setting the attachment type field to "registration" is used to indicate that the HSGW in the eHRPD network does not need to be in the registration process of the eHRPD network In this embodiment, the proxy mobile IP tunnel to the P-GW is established. In this embodiment, the proxy mobile IP tunnel between the HSGW and the P-GW is established during the handover process of the terminal from the LTE network to the eHRPD network.

VSNCP is an extended PPP network control protocol, and the VSNCP protocol is usually used in the eHRPD network to establish a PDN connection. In this embodiment, the attachment type field in the VSNCP configuration request message can be set to: "initial attachment", "handover" or "registration". When the attachment type field is set to "initial attachment" or "handover", the HSGW executes the corresponding processing flow.

In this step, the PDN ID in the configuration request message can be set as a default PDN ID, usually 15. If the terminal has established multiple PDN connections in LTE, the terminal does not need to initiate the registration of the non-default PDN connection, but establishes the non-default PDN connection after actually switching to the eHRPD network.

306: The HSGW establishes a gateway control session to the PCRF (Policy and Charging Rules Function, policy and charging rule function) entity, and the gateway control session may not be established when the terminal registers with the eHRPD network, but when the terminal switches to the eHRPD network Build again.

307: The HSGW judges whether the attachment type field in the received VSNCP configuration request message is "registration", if If yes, do not establish a proxy mobile IP tunnel to the P-GW, and directly return the VSNCP configuration confirmation message VSNCP Config-Ack to the terminal; otherwise, perform corresponding processing procedures according to the content of the attachment type field, such as initial attachment procedures, handover procedures, etc. wait.

308: The HSGW sends a VSNCP configuration request message VSNCP Config-Req to the terminal, and the PDN ID carried in the message is the same as the PDN ID in the VSNCP configuration request message sent by the terminal.

309: After receiving the VSNCP configuration request message sent by the HSGW, the terminal returns a VSNCP configuration confirmation message VSNCP Config-Ack to the HSGW, and the VSNCP configuration confirmation message carries the above PDN ID. So far, the terminal has completed the registration process to the eHRPD network.

310: If the terminal satisfies the condition of camping on LTE at this time, the terminal releases the eHRPD air interface connection established in the above eHRPD network registration process, and enters the dormant state. Usually, the terminal first negotiates the air interface session, and then establishes the air interface connection. After the terminal completes the registration with the eHRPD network, the eHRPD air interface connection can be released, but the eHRPD air interface session needs to be kept alive. By keeping the eHRPD air interface session alive, the eHRPD air interface session information can not be kept alive. Lost, eHRPD air interface session information includes but is not limited to: negotiated protocol type, attribute values and parameters used in the negotiated protocol, and so on.

311: When the terminal is a single-transmission and dual-reception terminal, the terminal switches to the LTE mode. If the terminal is a dual-transmission and dual-reception terminal, this step does not need to be performed.

Further, if the terminal receives paging from the LTE network during the eHRPD network registration process, the terminal suspends the ongoing eHRPD network registration, this registration fails, and processes the paging from the LTE network. When the terminal enters the LTE idle state Then re-register with the eHRPD network.

The above process is the eHRPD network registration process for the terminal residing on the LTE network. After the terminal completes the registration to the eHRPD network, if the terminal meets the conditions for switching to the eHRPD network at a certain moment, the terminal will initiate a handover to the eHRPD network. , see Figure 4, the switching process may include:

401: When the terminal judges that the channel quality of the LTE cell is less than the preset first threshold, and the channel quality of the eHRPD cell is higher than the preset second threshold, the terminal decides to switch to the eHRPD network, and sends a connection request message ConnectionRequest in the eHRPD network For the network side, perform standard connection establishment procedures. Wherein, the values of the first threshold and the second threshold are respectively set in advance, and usually the values of the two are different.

402: After the eAN receives the connection request message sent by the terminal, it judges according to the UATI (Unicast Access Terminal Identifier, access terminal unicast identifier) of the terminal carried in the message, and judges the subnet identifier in the UATI (i.e. color Code, Color Code) is its own identification, if yes, it is determined that UATI update is not required, otherwise, it is determined that the terminal has not updated UATI in time, the subnet identification in the UATI is the identification of the source subnet where the terminal is located, and the current terminal is located The subnet of the terminal is the target subnet of the terminal, so it is necessary to update the UATI, and determine the source of the terminal according to the subnet identifier in the UATI The eAN, that is, the S-eAN in the figure, obtains the air interface session information of the terminal from the S-eAN, specifically, executes the standard A13 session migration process to obtain the eHRPD air interface session information from the S-eAN. In Fig. 4, the judgment result is negative as an example for illustration.

403: If the eAN determines that no UATI update is required, the eA sends a TCA (Traffic Channel Assignment, service channel assignment message) to the terminal to establish a traffic channel for the terminal; if the eAN determines that a UATI update is required, the eA sends a UATI assignment to the terminal message (UATI Assignment) and TCA, update the UATI of the terminal, and establish a traffic channel for the terminal.

Among them, UATI is composed of two parts, the subnet ID and the terminal ID. The subnet ID is used to identify different subnets. Each subnet ID uniquely corresponds to a subnet and the eAN of the subnet; the terminal ID is in the subnet is uniquely valid and is used to identify terminals within the subnet.

404: If the terminal receives the TCA, it returns a TCC (Traffic Channel Complete, traffic channel completion message) to the eAN, indicating that the traffic channel is established successfully; if the terminal receives the UATI assignment message and the TCA, the terminal returns the UATI assignment completion message ( UATI Assignment Complete) and TCC, indicating that the UATI update is completed and the traffic channel is established successfully.

405: The eAN sends an All-Registration Request message (All-Registration Request) to the HSGW, and the message includes an Active-Start charging record, indicating that the terminal has accessed the eHRPD network.

406: After receiving the All registration request message, the HSGW judges whether the message contains an Active-Start charging record, and if it does, it indicates that a service channel has been established for the terminal, and the HSGW sends a proxy mobile IP binding update to the P-GW Message (PMIP Binding Update), to establish a proxy mobile IP tunnel.

407: P-GW interacts with PCRF, reports RAT (Radio Access Type, wireless access type) change event, initiates IP-CAN session modification process, and updates IP-CAN session.

408: The P-GW returns a proxy mobile IP binding confirmation message (PMIP Binding Ack). This step can also be performed after 406.

409: The HSGW returns an All-Registration Reply message (All-Registration Reply) message to the eAN, the proxy mobile IP tunnel is established, and the handover from the terminal to the eHRPD network is completed. This step can also be performed after 405.

410: If there is a dedicated QoS (Quality of Service, Quality of Service) flow before the terminal switches to the eHRPD network, the HSGW uses the RSVP (Resource reservation Protocol, Resource Reservation Protocol) protocol to notify the terminal to establish a corresponding QoS flow. This step is an optional step, indicated by a dotted line in the figure.

411: If the terminal has established multiple PDN connections before switching to the eHRPD network, the terminal initiates non-default PDN connection establishment after the switching. This step is also an optional step, indicated by a dotted line in the figure.

In addition, 410 and 411 can also be performed in parallel, and the dedicated QoS flow belonging to a certain PDN has to wait for the corresponding PDN connection It is established after the establishment. If the establishment of the dedicated QoS flow fails, the PCRF is notified to delete the corresponding QoS flow.

412: The P-GW sends a binding release indication message (Binding Revocation Indication) to the S-GW, triggering the release of resources on the LTE side.

The combination of Figure 3 and Figure 4 completely describes the process of registration and switching. Further, after the terminal completes the registration of the eHRPD network, the eHRPD air interface session can also be maintained, including the air interface session keep-alive and subnet change processing, see Figure 5, the air interface session keep-alive process can specifically include:

501: The terminal camps on the LTE network after completing the registration of the eHRPD network.

502: The eAN sends a keep alive request message (KeepAliveRequest) to the terminal to perform eHRPD air interface session detection. 503: After receiving the keep-alive request message, the terminal judges whether the currently received system broadcast message on the LTE network side indicates that registration to the eHRPD network is allowed, such as judging whether the pre-registration field (PreRegistrationAllowed) is "allowed", if yes , then perform eHRPD air interface session keep-alive processing, otherwise, do not perform eHRPD session keep-alive processing, in this case, if the eAN detects that the preset keep-alive timeout expires, delete the eHRPD air interface session and exit the registration state.

Wherein, the terminal performs eHRPD air interface session keep-alive processing, which may specifically include:

If the terminal is a dual-transmission and dual-reception terminal, the dual-transmission and dual-reception terminal performs air interface session keep-alive processing on the eHRPD network; if the terminal is a single-transmission and dual-reception terminal, the single-transmission and dual-reception terminal judges its own state. In the idle state, switch to the eHRPD mode for air interface session keep-alive processing, if it is in the LTE active state, then judge whether the preset keep-alive timeout is reached, if yes, switch to the eHRPD mode for air interface session keep-alive processing, otherwise, A flag is set to indicate that when the single-transmit and dual-receive terminal enters the LTE idle state, the air interface session keep-alive process will be performed.

Wherein, the preset keep-alive timeout time can be set to different values according to needs, for example, 18 hours is preset as the keep-alive timeout time. Further, the number of keep-alive timeouts can also be preset. For example, when the preset keep-alive timeout reaches 3 times, the air interface session is deleted. Then immediately switch to the eHRPD mode for air interface session keep-alive processing.

504: The terminal returns a keep-alive response message (KeepAliveResponse) to the eAN, and the eAN continues to retain the existing air interface session information.

505: The terminal turns off the eHRPD transmitter, switches to the LTE mode, that is, tunes to the LTE network.

Through the air interface session keep-alive process, the terminal can maintain the air interface session to ensure that the air interface session information is not lost, so as to avoid renegotiation of the air interface session when the handover is performed, so as to reduce the handover time of the terminal.

Referring to FIG. 6, after the terminal completes the registration of the eHRPD network, subnet change processing can also be performed, including: 601: After the terminal completes the registration of the eHRPD network, it camps on the LTE network.

602: The eAN periodically broadcasts quick configuration and sector parameter messages (QuickConfig & SectorParameters). 603: After receiving the quick configuration and sector parameter message, the terminal judges whether the subnet in the eHRPD network has changed according to the content of the quick configuration and sector parameter message. If the subnet changes, that is, the terminal has moved from the source subnet to For the target subnet, it is determined whether the currently received system broadcast message on the LTE network side indicates that registration to the eHRPD network is allowed, and if so, UATI update is performed when the terminal is in the LTE idle state, or when the terminal is in the LTE active state , the UATI update is not performed, but the UATI update is performed after the terminal enters the LTE idle state. If the terminal remains in the LTE active state until it is switched to the eHRPD network, the UATI update is performed while the terminal is switched.

Wherein, if the terminal is a single-transmission and dual-reception terminal, UATI update is performed after switching to the eHRPD mode, and if the terminal is a dual-transmission and dual-reception terminal, UATI update is performed directly on the eHRPD network.

604: The terminal performs the UATI assignment process, and obtains a new UATI from the T-eAN/PCF of the target subnet. If the source subnet and the target subnet belong to the same eAN, the eAN re-allocates a UATI to the terminal; if the source subnet If the subnet and the target subnet belong to different eANs, the T-eAN/PCF of the target subnet executes the A13 session to migrate the eHRPD air interface session information from the S-eAN/PCF of the source subnet, allocate a new UATI, and then send it to the terminal.

605: When the terminal is a single-transmission and dual-reception terminal, turn off the eHRPD transmitter and tune to the LTE network. If the terminal is a dual-transmission and dual-reception terminal, this step does not need to be performed.

Through subnet change processing, the terminal can ensure that the UATI is updated, and migrate the eHRPD air interface session information from the source S-eAN/PCF, thereby avoiding the loss of the negotiated air interface session information, so that the air interface session does not need to be renegotiated during the handover execution to reduce Toggle break time.

In addition, in the embodiment of the present invention, after the terminal registers with the eHRPD network, it can also perform PPP session maintenance, as follows:

When the terminal receives the PPP session detection message sent by the HSGW, if the terminal is in the LTE network, it does not respond to the PPP session detection message.

When the eAN air interface session keep-alive detection times out, the eHRPD air interface session will be released, and accordingly, the eAN/PCF will initiate the main A10 connection release, thereby triggering the HSGW to release the PPP session.

Usually, HSGW treats all users as Always-on users (that is, always online), and HSGW does not implement PPP Session timer session timing. The default value of the PPP inactivity timer (PPP inactivity timer) in the HSGW is 0, that is, the PPP inactivity period is infinite, and the HSGW will not initiate PPP session detection. Preferably, the PPP inactive period uses a default value of 0. When the PPP inactive period is configured as a non-zero value, then when the inactive period reaches the specified time, the HSGW will send an LCP Echo Request message to the terminal for PPP session detection After the terminal receives the PPP session detection message, if the terminal is currently camped on the LTE network, it will not return an LCP Echo Reply response message, so that the HSGW will release the PPP session, and re-establish PPP when the terminal switches to the eHRPD network next time. The terminal maintains the PPP session and does not respond to the PPP session detection of the HSGW, which can prevent the establishment of a service channel for the terminal due to the response to the PPP session, so that the network side can identify that the terminal has switched to the eHRPD network, resulting in unnecessary LTE network to eHRPD network switch.

In the embodiment of the present invention, further, after the terminal completes the registration to the eHRPD network, before the eHRPD air interface connection is released, if the terminal meets the conditions for switching to the eHRPD network at this time, the terminal can use the unreleased eHRPD air interface Connection execution switching process, see Figure 7, specifically may include:

701: The terminal completes the registration from the LTE network to the eHRPD network, and before releasing the eHRPD air interface connection, it detects that the terminal meets the conditions for switching to the eHRPD network, and sends a VSNCP configuration request message VSNCP Config-Req to the HSGW, the attachment type in the message The field is set to "Handover Attach", which triggers the establishment of the Proxy Mobile IP tunnel.

702: After the HSGW receives the VSNCP configuration request message, since the eHRPD air interface connection already exists, there is no need to re-establish the eHRPD air interface connection, and the UATI updates and establishes the service channel, directly establishes the proxy mobile IP tunnel, and uses the proxy mobile IP tunnel to complete the terminal Handover to eHRPD network. Wherein, the HSGW establishes the proxy mobile IP tunnel and the terminal completes the handover process to the eHRPD network, which are specifically the same as 406-412 in the embodiment of the present invention, and will not be repeated here.

In the method of the embodiment of the present invention, the order of each step can be adjusted according to actual needs.

The above method provided by the embodiment of the present invention registers through the eHRPD air interface before the terminal switches to the eHRPD network, and completes the eHRPD air interface session negotiation, PPP negotiation, and EAP-AKA authentication before the handover from LTE to eHRPD occurs. At this time, only the eHRPD air interface connection is established and the proxy mobile IP tunnel is switched, which greatly reduces the service interruption time of switching from the LTE network to the eHRPD network. Compared with the existing optimized handover, it is not completed through LTE and S101 tunnels, which greatly reduces the complexity of the network. Moreover, there is no need to modify the protocol stack of the terminal, which reduces the complexity of the terminal. In addition, after the terminal completes the eHRPD network registration, when the terminal is in the LTE idle state, the air interface session is kept alive and the subnet is changed as required, which can ensure that the terminal will not exit the eHRPD registration state and ensure the validity of the eHRPD registration. By preferentially performing eHRPD air interface session information maintenance in the LTE idle state, it is possible to avoid impact on ongoing services of the LTE network, improve service quality, and improve user experience. Referring to FIG. 8, the embodiment of the present invention also provides a network switching method, which may specifically include:

801: The LTE network side sends a message to the terminal, indicating that the terminal is allowed to register with the eHRPD network;

802: When the terminal completes registration to the eHRPD network through the eHRPD air interface and decides to switch to the eHRPD network, the eHRPD network side establishes a proxy mobile IP tunnel, and the proxy mobile IP tunnel completes the handover of the terminal to the eHRPD network. Further, the above method may also include:

During the registration process of the terminal on the eHRPD network, the HSGW on the eHRPD network side receives the device vendor extended network control protocol VSNCP configuration request message sent by the terminal; the HSGW judges whether the attachment type field carried in the configuration request message is registration, and if so, then The HSGW does not establish a proxy mobile IP tunnel to the packet data network gateway during the registration process.

Further, the above method may also include:

After the terminal completes the registration to the eHRPD network, the eAN on the eHRPD network side sends an air interface session keep-alive request message to the terminal; and the eAN receives the air interface session keep-alive response message returned by the terminal according to the instruction from the LTE network side and its own state.

Further, the above method may also include:

When the terminal completes the registration with the eHRPD network and detects that the subnet in the eHRPD network has changed, the eAN of the target subnet where the terminal is currently located judges whether it is the eAN of the source subnet where the terminal is located before the subnet changes. , the eAN allocates an access terminal unicast identifier UATI to the terminal, otherwise, the eAN of the target subnet migrates the eHRPD air interface session information from the eAN of the source subnet, and allocates a new UATI to the terminal, and then sends it to the terminal.

Further, before establishing the proxy mobile IP tunnel on the eHRPD network side, it may also include:

The eAN on the eHRPD network side receives the connection request message sent by the terminal in the eHRPD network;

According to the connection request message, the eAN judges whether the subnet identifier in the access terminal unicast identifier of the terminal is its own identifier; if yes, the eAN sends a service channel assignment message to the terminal, and establishes a service channel for the terminal;

Otherwise, the eAN determines the source eAN of the terminal according to the subnet identifier in the unicast identifier of the access terminal, and obtains the air interface session information of the terminal from the source eAN, and then sends an access terminal unicast identifier assignment message and a traffic channel assignment message to the terminal message, update the access terminal unicast identifier of the terminal, and establish a service channel for the terminal.

In the method of the embodiment of the present invention, the order of each step can be adjusted according to actual needs.

The above method provided by the embodiment of the present invention registers through the eHRPD air interface before the terminal switches to the eHRPD network, and completes the eHRPD air interface session negotiation, PPP negotiation, and EAP-AKA authentication before the handover from LTE to eHRPD occurs. At this time, only the eHRPD air interface connection is established and the proxy mobile IP tunnel is switched, which greatly reduces the service interruption time of switching from the LTE network to the eHRPD network. Compared with the existing optimized handover, it is not completed through LTE and S101 tunnels, which greatly reduces the complexity of the network. Moreover, there is no need to modify the protocol stack of the terminal, which reduces the complexity of the terminal. In addition, after the terminal completes the eHRPD network registration, when the terminal is in the LTE idle state, the air interface session is kept alive and the subnet is changed as required, which can ensure that the terminal will not exit the eHRPD registration state and ensure the validity of the eHRPD registration. By preferentially performing eHRPD air interface session information maintenance in the LTE idle state, it is possible to avoid the ongoing maintenance of the LTE network. The business of the bank is affected, the service quality is improved, and the user experience is improved. Referring to FIG. 9, an embodiment of the present invention also provides a terminal, which may include:

The registration module 901 is configured to register the eHRPD network through the eHRPD air interface according to the instruction of the LTE network when the terminal resides on the LTE network;

The trigger module 902 is configured to establish an air interface connection after the registration module 901 completes the registration and the terminal decides to switch to the eHRPD network, and trigger the eHRPD network to establish a proxy mobile IP tunnel from the HSGW to the P-GW, and the proxy mobile IP tunnel is used to complete Handover of the terminal from the LTE network to the eHRPD network.

When the above-mentioned terminal is a single-sending and double-receiving terminal, the registration module 901 may specifically include:

The first registration unit is used for if the single-transmission and dual-reception terminal residing in the LTE network receives a system broadcast message from the LTE network side, and the system broadcast message indicates that registration to the eHRPD network is allowed, then the single-transmission and dual-reception terminal is When the LTE is idle, switch to the eHRPD mode to register the eHRPD network through the eHRPD air interface;

When the above-mentioned terminal is a dual-transmission and dual-reception terminal, the registration module 901 may specifically include:

The second registration unit is used for if the dual-transmission and dual-reception terminal residing in the LTE network receives a system broadcast message from the LTE network side, and the system broadcast message indicates that registration to the eHRPD network is allowed, then the dual-transmission and dual-reception terminal is In the LTE idle state or the LTE active state, the eHRPD network registration is performed through the eHRPD air interface.

Further, the above-mentioned terminal may further include:

The connection establishment module is configured to send a device vendor extended network control protocol VSNCP configuration request message to the eHRPD network side during the registration process of the terminal on the eHRPD network, and request to establish a packet data network connection. When the attachment type field carried in the configuration request message When the content of is registration, it indicates that the HSGW in the eHRPD network does not need to establish a proxy mobile IP tunnel from the HSGW to the P-GW during the registration process.

Further, when the above-mentioned terminal is a dual-transmission and dual-reception terminal, it may also include:

The first air interface session keep-alive module is configured to, after the dual-transmit and dual-receive terminal registers with the eHRPD network, when the dual-transmit and dual-receive terminal receives the air interface session keep-alive request message sent by the evolved access network eAN, if the dual-transmit and dual-receive terminal The system broadcast message on the LTE network side currently received by the dual-receiving terminal indicates that registration to the eHRPD network is allowed, and the dual-transmitting and dual-receiving terminal performs air interface session keep-alive processing;

Alternatively, when the above-mentioned terminal is a single-transmission and dual-reception terminal, it may also include:

The second air interface session keep-alive module is used to register the eHRPD network after the single-transmission and dual-reception terminal receives the air interface session keep-alive request message sent by the eAN. The received system broadcast message on the LTE network side indicates that registration to the eHRPD network is allowed, and the single-transmit and dual-receive terminal judges its own status. If it is In the LTE idle state, the air interface session keep-alive process is performed. If it is in the LTE active state, it is judged whether the preset keep-alive timeout period is reached. If yes, the air interface session is kept alive. When the dual-receiving terminal enters the LTE idle state, it performs air interface session keep-alive processing.

Further, the above terminal may also include:

The subnet change processing module is configured to, after the terminal registers on the eHRPD network, when the terminal detects that the subnet in the eHRPD network has changed, if the system broadcast message currently received by the terminal on the LTE network side indicates that registration is allowed to On the eHRPD network, when the terminal is in the LTE idle state, the access terminal unicast identity update is performed, or when the terminal is in the LTE active state, the access terminal unicast identity update is performed during handover to the eHRPD network.

Further, the above terminal may also include:

The point-to-point session maintenance module is configured to, after the terminal registers on the eHRPD network, when the terminal receives the point-to-point session detection message sent by the high-rate packet data service gateway, if the terminal is in the LTE network, then it does not respond to the point-to-point session detection message.

Various modules in the embodiment of the present invention can be integrated into one body, or can be deployed separately. The above modules can be combined into one module, or can be further split into multiple sub-modules.

The above-mentioned terminal provided by the embodiment of the present invention registers through the eHRPD air interface before handover to the eHRPD network, and completes the eHRPD air interface session negotiation, PPP negotiation, and EAP-AKA authentication before the handover from LTE to eHRPD occurs. Only the eHRPD air interface connection is established and the proxy mobile IP tunnel is switched, which greatly reduces the service interruption time of switching from the LTE network to the eHRPD network. Compared with the existing optimized handover, it is not completed through LTE and S101 tunnels, which greatly reduces the complexity of the network. Moreover, there is no need to modify the protocol stack of the terminal, which reduces the complexity of the terminal. In addition, after the terminal completes the eHRPD network registration, when the terminal is in the LTE idle state, the air interface session is kept alive and the subnet is changed as required, which can ensure that the terminal will not exit the eHRPD registration state and ensure the validity of the eHRPD registration. By preferentially performing eHRPD air interface session information maintenance in the LTE idle state, it is possible to avoid impact on ongoing services of the LTE network, improve service quality, and improve user experience. Referring to FIG. 10, an embodiment of the present invention also provides a base station located in an LTE network, which may include:

The message generating module 1001 is configured to generate a message indicating that the terminal is allowed to register with the eHRPD network; the sending module 1002 is configured to send the message generated by the message generating module 1001 to a terminal residing in the LTE network, indicating that the terminal is allowed to register with the eHRPD network registration, so that the terminal registers with the eHRPD network through the eHRPD air interface.

The above-mentioned base station provided by the embodiment of the present invention allows the terminal to register with the eHRPD network by instructing the terminal, so that the terminal can complete the registration with the eHRPD network before the handover from the LTE network to the eHRPD network occurs, which greatly reduces the The service interruption time of handover from the LTE network to the eHRPD network is reduced. The embodiment of the present invention also provides a gateway located in the eHRPD network, which may include:

The tunnel establishment module is used to establish a proxy mobile IP tunnel when the terminal completes registration from the LTE network to the eHRPD network and decides to switch to the eHRPD network, and completes the handover from the terminal to the eHRPD network through the proxy mobile IP tunnel.

Further, referring to FIG. 11, the above gateway may also include:

The receiving module 1101 is configured to receive the equipment vendor extended network control protocol VSNCP configuration request message sent by the terminal during the registration process of the eHRPD network;

Correspondingly, the tunnel establishment module 1102 can be specifically configured to determine whether the content of the attachment type field carried in the VSNCP configuration request message received by the receiving module 1101 is registration, and if so, do not establish a tunnel to the packet data network gateway P during the registration process. - The proxy mobile IP tunnel of GW, when the terminal completes the registration from the LTE network to the eHRPD network and decides to switch to the eHRPD network, establishes the proxy mobile IP tunnel to the P-GW, and the proxy mobile IP tunnel completes the handover of the terminal to the eHRPD network , otherwise, perform corresponding processing according to the content of the attachment type field.

The above-mentioned gateway provided by the embodiment of the present invention judges the attachment type field, and does not establish a proxy mobile IP tunnel when the field is registered, so that when the terminal performs eHRPD network registration, the proxy mobile IP tunnel is not established, so that the terminal is switched to In the eHRPD network, the service interruption time of handover is greatly shortened. Referring to FIG. 12, an embodiment of the present invention also provides an eAN located in the eHRPD network, and the eAN may include at least one of the following three modules:

The air interface session keep-alive module 1201 is configured to send an air interface session keep-alive request message to the terminal after the terminal completes the registration from the Long Term Evolution LTE network to the eHRPD network, and receive an air interface message returned by the terminal according to an instruction from the LTE network side and its own state. session keep alive response message;

The subnet change processing module 1202 is used to determine whether the eAN, which is the target subnet where the terminal is currently located, is a subnet when the terminal completes the registration from the LTE network to the eHRPD network and detects that the subnet in the eHRPD network has changed If the eAN of the source subnet where the terminal is located before the change is, assign an access terminal unicast identifier UATI to the terminal, otherwise, migrate the eHRPD air interface session information from the eAN of the source subnet, and assign a UATI to the terminal, and then send to end

¾;

The service channel establishment module 1203 is used to receive the connection request message sent by the terminal in the eHRPD network after judging to switch to the eHRPD network, and judge whether the subnet identifier in the access terminal unicast identifier UATI of the terminal is eAN according to the connection request message ID, if yes, send a traffic channel assignment message to the terminal, and establish a traffic channel for the terminal, otherwise, determining the source eAN of the terminal according to the subnet identifier in the UATI, and obtaining the air interface session information of the terminal from the source eA, and then sending an access terminal unicast identifier assignment message and a traffic channel assignment message to the terminal, updating the UATI of the terminal, and Establish a traffic channel for the terminal.

FIG. 12 illustrates that the eAN includes the above three modules as an example. In practical applications, the eAN may only include any one or any two of the above three modules.

The above-mentioned eAN provided by the embodiment of the present invention can ensure that the terminal will not exit the eHRPD registration state by performing air interface session keep-alive processing and subnet change processing, thereby ensuring the validity of eHRPD registration; performing air interface session migration of the terminal according to the UATI of the terminal, which can When the terminal is handed over from the LTE network to the eHRPD network, it is not necessary to perform eHRPD air interface session negotiation again, and the terminal is not required to perform subnet change processing immediately when it detects a subnet change of the eHRPD network in the LTE active state. Referring to FIG. 13, an embodiment of the present invention also provides a network system, which may include:

The terminal 1301 is configured to register the eHRPD network through the eHRPD air interface according to the instructions of the LTE network when it resides on the LTE network, and then establish an air interface connection, and trigger the eHRPD network to establish a proxy mobile IP tunnel from the HSGW to the P-GW, The proxy mobile IP tunnel is used to complete the handover of the terminal from the LTE network to the eHRPD network;

The base station 1302 is located in the LTE network, and is used to send a message to the terminal when the terminal is camped on the LTE network, indicating that the terminal is allowed to register with the eHRPD network. Specifically, the base station can be an eNodeB;

The high-rate packet data service gateway HSGW 1303 is located on the eHRPD network, and is used to establish a proxy mobile IP tunnel between itself and the P-GW when the terminal completes registration from the LTE network to the eHRPD network and decides to switch to the eHRPD network. The tunnel completes the handover from the terminal to the eHRPD network.

Further, the above system may further include: eAN, located in the eHRPD network, where the eAN includes at least one of the following three modules:

The air interface session keep-alive module is used to send an air interface session keep-alive request message to the terminal after the terminal completes the registration from the LTE network to the eHRPD network, and receive the air interface session keep-alive returned by the terminal according to the instruction from the LTE network side and its own state response message;

The subnet change processing module is used to determine whether the eAN, which is the target subnet where the terminal is currently located, is a subnet change when the terminal completes the registration from the LTE network to the eHRPD network and detects that the subnet in the eHRPD network has changed If the eAN of the source subnet where the terminal is located is, an access terminal unicast identifier UATI is allocated to the terminal, otherwise, the eHRPD air interface session information is migrated from the eAN of the source subnet, and a UATI is allocated to the terminal, and then sent to The terminal; a service channel establishment module, configured to receive the information sent by the terminal in the eHRPD network after it decides to switch to the eHRPD network The connection request message, judging whether the subnet identifier in the access terminal unicast identifier UATI of the terminal is the identifier of the eAN according to the connection request message, and if so, sending a service channel assignment message to the terminal to establish a service channel for the terminal, otherwise, determining the source eAN of the terminal according to the subnet identifier in the UATI, and obtaining the air interface session information of the terminal from the source eAN, and then sending an access terminal unicast identifier assignment message and a traffic channel assignment message to the terminal, updating the UATI of the terminal, and Establish a traffic channel for the terminal.

Each unit of the system in the embodiment of the present invention may be integrated in one device, or may be distributed in multiple devices. The above units can be combined into one unit, and can also be further split into multiple sub-units.

The above system provided by the embodiment of the present invention performs eHRPD network registration before the terminal switches to the eHRPD network, and completes eHRPD air interface session negotiation, PPP negotiation, and EAP-AKA authentication before the handover from the LTE network to the eHRPD network occurs, During the handover, only the eHRPD air interface connection is established and the proxy mobile IP tunnel is handed over, which greatly reduces the service interruption time of the handover from the LTE network to the eHRPD network. Compared with the existing optimized handover, it is not completed through the LTE and S101 tunnels, which greatly reduces the complexity of the network. Moreover, there is no need to modify the protocol stack of the terminal, which reduces the complexity of the terminal. In addition, after the terminal completes the eHRPD network registration, when the terminal is in the LTE idle state, the air interface session is kept alive and the subnet is changed as required, which can ensure that the terminal will not exit the eHRPD registration state and ensure the validity of the eHRPD registration. By preferentially performing eHRPD air interface session information maintenance in the LTE idle state, it is possible to avoid impact on ongoing services of the LTE network, improve service quality, and improve user experience.

Through the above description of the embodiments, those skilled in the art can clearly understand that the present invention can be implemented by means of software plus a necessary general-purpose hardware platform, of course, it can also be implemented by hardware, or a combination of the two. Based on this understanding, the essence of the technical solution of the present invention or the part that contributes to the prior art can be embodied in the form of software products, and the software modules or computer software products can be stored in a storage medium, including several instructions It is used to make a computer device (which may be a personal computer, a server, or a network device, etc.) execute the methods described in various embodiments of the present invention. The storage medium may be random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or known in the technical field any other form of storage media.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection of the present invention within range.

Claims (15)

Claims 1. A network switching method, characterized in that it is applied to a long-term evolution LTE network and an evolved high-rate packet data eHRPD network, including: The LTE network side sends a message to the terminal, indicating that the terminal is allowed to register with the eHRPD network; when the terminal completes the registration with the eHRPD network through the eHRPD air interface and decides to switch to the eHRPD network, the The eHRPD network side establishes a proxy mobile IP tunnel from the high-rate packet data service gateway HSGW to the packet data network gateway P-GW, and the proxy mobile IP tunnel completes the handover of the terminal to the eHRPD network. 2. The network switching method according to claim 1, further comprising: During the registration process of the terminal on the eHRPD network, the high-rate packet data service gateway HSGW on the eHRPD network side receives the request message sent by the terminal; The HSGW judges whether the attachment type field carried in the request message is registration, and if yes, the HSGW does not establish a proxy mobile IP tunnel to the packet data network gateway during the registration process. 3. The network switching method according to claim 1, further comprising: After the terminal completes the registration to the eHRPD network, the evolved access network eAN on the eHRPD network side sends an air interface session keep-alive request message to the terminal; The eAN receives the air interface session keep-alive response message returned by the terminal according to the instruction of the LTE network side and its own state. 4. The network switching method according to claim 1, further comprising: When the terminal completes the registration to the eHRPD network and detects that the subnet in the eHRPD network has changed, the eAN of the target subnet where the terminal is currently located assigns an access terminal unicast identifier UATI to the terminal , sending the UATI to the terminal. 5. The network switching method according to claim 1, characterized in that, before the eHRPD network side establishes a proxy mobile IP tunnel, it further includes: The eAN on the eHRPD network side receives the connection request message sent by the terminal in the eHRPD network; the eAN judges whether the subnet identifier in the access terminal unicast identifier of the terminal is for its own identification; If so, the eAN sends a service channel assignment message to the terminal to establish a service channel for the terminal; otherwise, the eAN determines the terminal's source eAN, and obtain the air interface session information of the terminal from the source eAN, and then send an access terminal unicast identity assignment message to the terminal and a traffic channel assignment message, update the access terminal unicast identifier of the terminal, and establish a traffic channel for the terminal. 6. A terminal, characterized by comprising: a registration module, configured to perform eHRPD network registration through an evolved high-rate packet data eHRPD air interface according to an instruction of the LTE network when the terminal resides in the Long Term Evolution LTE network; A triggering module, configured to establish an air interface connection after the registration module completes the registration and the terminal decides to switch to the eHRPD network, and trigger the eHRPD network to establish a link from the high-rate packet data service gateway HSGW to the packet data network gateway P- A proxy mobile IP tunnel of the GW, and the proxy mobile IP tunnel completes the handover of the terminal from the LTE network to the eHRPD network. 7. The terminal according to claim 6, wherein the registration module comprises: The first registration unit is configured to, if the terminal residing in the LTE network receives a message from the LTE network side, and the message indicates that registration to the eHRPD network is allowed, then when the terminal is in the LTE idle state, switch Go to the eHRPD mode and register the eHRPD network through the eHRPD air interface; or, The second registration unit is configured to, if the terminal residing in the LTE network receives a message from the LTE network side, and the message indicates that registration to the eHRPD network is allowed, then the terminal is in the LTE idle state or LTE activated In the state, register with the eHRPD network through the eHRPD air interface. 8. The terminal according to claim 6, further comprising: A connection establishment module, configured to send a request message to the eHRPD network side during the registration process of the terminal on the eHRPD network, requesting to establish a packet data network connection, and when the content of the attachment type field carried in the request message is registration, Then instruct the high-rate packet data serving gateway HSGW in the eHRPD network not to establish a proxy mobile IP tunnel from the HSGW to the packet data network gateway P-GW in the registration process. 9. The terminal according to claim 6, wherein the terminal further comprises: The first air interface session keep-alive module is configured to, after the terminal registers with the eHRPD network, when the terminal receives the air interface session keep-alive request message sent by the evolved access network eAN, if the terminal currently receives The message on the LTE network side indicates that registration to the eHRPD network is allowed, and the terminal performs air interface session keep-alive processing; or, The second air interface session keep-alive module is configured to, after the terminal registers with the eHRPD network, when the terminal receives the air interface session keep-alive request message sent by iJ eAN, if the terminal currently receives the LTE network side Indicated in the message to allow registration to the eHRPD network, the terminal judges its own state, if it is in the LTE idle state, then performs air interface session keep-alive processing, and if it is in the LTE active state, then judges whether the preset keep-alive timeout is reached time, if yes, proceed Air interface session keep-alive processing, otherwise, a flag is set to indicate that when the terminal enters the LTE idle state, air interface session keep-alive processing is performed. 10. The terminal according to claim 6, wherein the terminal further comprises: A subnet change processing module, configured to, after the terminal registers with the eHRPD network, when the terminal detects that the subnet in the eHRPD network has changed, if the terminal currently receives a message from the LTE network side Indicates that registration to the eHRPD network is allowed, then when the terminal is in the LTE idle state, update the access terminal unicast identity, or when the terminal is in the LTE active state, perform an access terminal during the process of switching to the eHRPD network Incoming terminal unicast identity update. 11. The terminal according to claim 6, further comprising: A point-to-point session maintenance module, configured to, after the terminal registers with the eHRPD network, when the terminal receives a point-to-point session detection message from a high-rate packet data service gateway, if the terminal is in the LTE network, then Do not respond to the point-to-point session detection message. 12. A gateway, characterized in that it is located in an evolved high-rate packet data eHRPD network, and the gateway includes: a receiving module, configured to receive a request message sent by a terminal during the registration process of the eHRPD network; A tunnel establishment module, configured to determine whether the content of the attachment type field carried in the request message received by the receiving module is registration, and if so, do not establish a proxy mobile IP address to the packet data network gateway P-GW during the registration process. Tunnel, when the terminal completes the registration from the LTE network to the eHRPD network and decides to switch to the eHRPD network, establishes a proxy mobile IP tunnel to the P-GW, and the proxy mobile IP tunnel is completed Handover of the terminal to the eHRPD network. 13. A network system, characterized by comprising: The terminal is configured to register the eHRPD network through the eHRPD air interface according to an instruction from the LTE network when it resides on the Long Term Evolution LTE network, establish an air interface connection with the eHRPD network, and trigger the eHRPD network to establish a high-level A proxy mobile IP tunnel from the packet data service gateway HSGW to the packet data network gateway P-GW; the base station, located in the LTE network, is used to send a message to the terminal, indicating that the terminal is allowed to register with the eHRPD network; A high-rate packet data service gateway HSGW, located on the eHRPD network, is used when the terminal completes from the When the LTE network registers with the eHRPD network, a proxy mobile IP tunnel to the packet data network gateway P-GW is established, and the proxy mobile IP tunnel completes the handover of the terminal from the LTE network to the eHRPD network. 14. The network system according to claim 13, further comprising: an evolved access network eAN, located in the eHRPD network; The eAN includes at least one of the following three modules: An air interface session keep-alive module, configured to send an air interface session keep-alive request message to the terminal after the terminal completes registration from the LTE network to the eHRPD network, and receive an instruction from the terminal based on the LTE network side and its own The air interface session keep-alive response message returned by the status; The subnet change processing module is configured to: when the terminal completes the registration from the LTE network to the eHRPD network and detects that the subnet in the eHRPD network has changed, give the eAN as the target subnet where the terminal is currently located The terminal allocates an access terminal unicast identifier UATI, and sends the UATI to the terminal; A service channel establishment module, configured to receive a connection request message sent by the terminal in the eHRPD network after deciding to switch to the eHRPD network, and judge the terminal's access terminal unicast identifier UATI according to the connection request message Whether the subnet identifier is the identifier of the eAN, if so, send a service channel assignment message to the terminal, and establish a service channel for the terminal, otherwise, determine the terminal's address according to the subnet identifier in the UATI The source eAN obtains the air interface session information of the terminal from the source eAN, sends an access terminal unicast identifier assignment message and a traffic channel assignment message to the terminal, updates the UATI of the terminal, and establishes a traffic channel. 15. The network system according to claim 13, wherein the base station comprises: A message generating module, configured to generate a message, the message indicating that the terminal is allowed to register with the evolved high-rate packet data eHRPD network; a sending module, configured to send the message generated by the message generating module to a terminal residing in the LTE network, indicating that the terminal is allowed to register with an evolved high-rate packet data eHRPD network, so that the terminal passes through the eHRPD air interface A registration with the eHRPD network is performed.