CN118102404A - Service continuity method and system for diversion gateway change - Google Patents

Abstract

The invention discloses a business continuity method and a system for changing a shunt gateway, which relate to the technical field of mobile communication, are applied under a 5G core network architecture, and when the shunt gateway is changed due to an N2 switching process, a source shunt gateway actively transmits UE IP address and GTPU tunnel information to a target shunt gateway by means of 5G core network switching signaling, so as to complete the association of user information, actively transmits an analog data packet, updates DN route information and ensures business continuity; when the XN switching process causes the change of the distribution gateway, the target distribution gateway initiates the acquisition of the UE IP address and the GTPU tunnel information to the source distribution gateway through the SourceAMF _UE_NGAP_ID field, so as to be related to the user information, update the local DN routing information and ensure the service continuity. The invention can ensure that the shunt gateway is switched in the service forwarding process, and service interruption is avoided or service interruption time is reduced.

Description

A business continuity method and system for offloading gateway changes

Technical Field

The present invention relates to the field of mobile communication technology, and in particular to a service continuity method and system for offloading gateway changes.

Background technique

Traffic distribution gateway products generally refer to systems or devices used for traffic management and routing in network architectures. They can handle functions such as traffic monitoring, logging, current limiting control, blacklist and whitelist management, and load balancing. Here are some key points:

1. Reverse proxy and static resource mapping: Nginx is a widely used diversion gateway product that can realize reverse proxy and static resource mapping, help forward client requests to the correct server, and provide the function of caching static resources.

2. User plane function: In the 5G core network (5GC), UPF (user plane function) is an important network element, which supports the routing and forwarding of user service data, as well as the identification and policy execution of data and services. UPF interacts with other network elements through the N4 interface and is a key component for achieving traffic diversion and management in the 5G network.

3. Microservice Gateway: In the microservice architecture, the API gateway plays an important role. It not only manages the global strategy of the API, but also handles the calls and data exchanges between services. When designing a microservice gateway, it is necessary to consider how to handle tens of billions of traffic to ensure the stability and scalability of the system.

4. Traffic management strategy: Traffic gateway also focuses on global API management strategies, such as global traffic monitoring, logging, global flow control, blacklist and whitelist control, and load balancing of access requests to business systems. These functions are similar to firewalls to a certain extent, but they focus more on fine-grained management and optimization of traffic.

In summary, offload gateway products play a vital role in modern network architecture. Whether in traditional Web services or in emerging 5G networks, they are key components to ensure efficient and secure network operation.

The diversion gateway product is deployed between the base station and the core network. The function of this product is to achieve central and local data diversion. The central traffic is transmitted to the core computer room through the transmission network, and the local traffic is unloaded to the local DN through the diversion gateway to reduce transmission delay. The diversion gateway product implements some UPF functions and completes the interaction between local data and base stations.

Currently, there are fewer offload gateway products related to 5G services on the market, and there is a lack of mature technical solutions. Facing the offload gateway switching scenario caused by terminal movement, there is currently no reference solution.

Summary of the invention

Since the target base station will not obtain the UE IP address information during the offload gateway switching process, the downlink route cannot be updated in time, which will cause service interruption. The present invention provides a service continuity method and system for offload gateway change to ensure that the offload gateway is switched during service forwarding without service interruption or reduce the service interruption time.

In a first aspect, the present invention provides a service continuity method for changing a shunt gateway, and the technical solution adopted to solve the above technical problem is as follows:

A business continuity method for offloading gateway changes is applied under the 5G core network architecture, using 5G core network switching signaling.

When the N2 switching process causes the offload gateway to change, the source offload gateway actively sends the UE IP address and GTPU tunnel information to the target offload gateway to complete the association of user information, and actively sends simulated data packets to update DN routing information to ensure business continuity;

When the XN switching process causes the offload gateway to change, the target offload gateway initiates the UE IP address and GTPU tunnel information acquisition to the source offload gateway through the SourceAMF_UE_NGAP_ID field, and then associates it with the user information and updates the local DN routing information to ensure business continuity.

Optionally, when the N2 switching process causes the offload gateway to change,

The source offload gateway searches for the locally configured target gateway information through the target base station information in the handover request, and proactively forwards the user UE IP and GTPU tunnel information to the target offload gateway;

After the target offload gateway receives the message, it associates the downlink GTPU tunnel information with the latest tunnel information to establish a new relationship;

After the relationship is established, the upstream data packet is simulated to complete the path update.

Further optionally, when the N2 switching process causes the offload gateway to change,

The source offload gateway discovers the target base station by identifying the Handover Required signaling, and identifies the UE-associated GTPU tunnel information and UE IP address;

Through the source offload gateway information associated with the locally configured target base station, the UE IP address and GTPU tunnel are sent to the target offload gateway through the Agent of the source offload gateway;

After receiving the information, the target offload gateway identifies the user information through the Handover Command and Handover Complete information, and associates the latest information with the received downlink GTPU tunnel information and UE IP address;

The target offload gateway simulates the uplink data packet and forwards it to the DN. The routing information of the DN is changed to the target offload gateway, and subsequent data is transmitted to the target base station and terminal through the target offload gateway.

Optionally, when the XN switching process causes the offload gateway to change,

The target base station uses the SourceAMF_UE_NGAP_ID field to index the user information to the source offload gateway, and after completing the data acquisition, associates the latest GTPU tunnel information through the UE IP address to establish a new relationship;

After the relationship is established, the upstream data packet is simulated to complete the path update.

Further optionally, when the XN switching process causes the offload gateway to change,

The target offload gateway obtains SourceAMF_UE_NGAP_ID information based on the received Path Switch Request, queries the source offload gateway information locally, and forwards this information to the source offload gateway through the Agent;

After receiving the data packet, the source offload gateway queries the UE context information and forwards the UE-associated information including the GTPU tunnel information and the UE IP address to the target offload gateway;

The target offload gateway learns the latest tunnel information based on Path Switch Request and Path Switch Request Ack and associates it with the information obtained from the source offload gateway;

The target offload gateway simulates the uplink data packet and forwards it to the DN. The routing information of the DN is changed to the target offload gateway, and subsequent data is transmitted to the target base station and terminal through the target offload gateway.

In a second aspect, the present invention provides a business continuity system for offloading gateway changes, and the technical solution adopted to solve the above technical problems is as follows:

A business continuity system for changing a traffic diversion gateway is applied under a 5G core network architecture and uses 5G core network switching signaling. The implementation process involves a source traffic diversion gateway and a target traffic diversion gateway, wherein:

When the N2 switching process causes the offload gateway to change, the source offload gateway actively sends the UE IP address and GTPU tunnel information to the target offload gateway to complete the association of user information, and actively sends simulated data packets to update DN routing information to ensure business continuity;

When the XN switching process causes the offload gateway to change, the target offload gateway initiates the UE IP address and GTPU tunnel information acquisition to the source offload gateway through the SourceAMF_UE_NGAP_ID field, and then associates it with the user information and updates the local DN routing information to ensure business continuity.

Optionally, when the N2 switching process causes the offload gateway to change,

The source offload gateway searches for the locally configured target gateway information through the target base station information in the handover request, and proactively forwards the user UE IP and GTPU tunnel information to the target offload gateway;

After the target offload gateway receives the message, it associates the downlink GTPU tunnel information with the latest tunnel information to establish a new relationship;

After the relationship is established, the upstream data packet is simulated to complete the path update.

Further optionally, when the N2 switching process causes the offload gateway to change,

The source offload gateway discovers the target base station by identifying the Handover Required signaling, and identifies the UE-associated GTPU tunnel information and UE IP address;

Through the source offload gateway information associated with the locally configured target base station, the UE IP address and GTPU tunnel are sent to the target offload gateway through the Agent of the source offload gateway;

After receiving the information, the target offload gateway identifies the user information through the Handover Command and Handover Complete information, and associates the latest information with the received downlink GTPU tunnel information and UE IP address;

The target offload gateway simulates the uplink data packet and forwards it to the DN. The routing information of the DN is changed to the target offload gateway, and subsequent data is transmitted to the target base station and terminal through the target offload gateway.

Optionally, when the XN switching process causes the offload gateway to change,

The target base station uses the SourceAMF_UE_NGAP_ID field to index the user information to the source offload gateway, and after completing the data acquisition, associates the latest GTPU tunnel information through the UE IP address to establish a new relationship;

After the relationship is established, the upstream data packet is simulated to complete the path update.

Further optionally, when the XN switching process causes the offload gateway to change,

The target offload gateway obtains SourceAMF_UE_NGAP_ID information based on the received Path Switch Request, queries the source offload gateway information locally, and forwards this information to the source offload gateway through the Agent;

After receiving the data packet, the source offload gateway queries the UE context information and forwards the UE-associated information including the GTPU tunnel information and the UE IP address to the target offload gateway;

The target offload gateway learns the latest tunnel information based on Path Switch Request and Path Switch Request Ack and associates it with the information obtained from the source offload gateway;

The target offload gateway simulates the uplink data packet and forwards it to the DN. The routing information of the DN is changed to the target offload gateway, and subsequent data is transmitted to the target base station and terminal through the target offload gateway.

The service continuity method and system for changing a shunt gateway of the present invention has the following beneficial effects compared with the prior art:

The present invention solves the problem that the target base station cannot obtain UE IP address information during the offload gateway switching process, the downlink route cannot be updated in time, and service interruption will occur. It can ensure that the offload gateway is switched during the service forwarding process without service interruption or reduce the service interruption time.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of an N2 switching networking architecture in an embodiment of the present invention;

FIG. 2 is a flow chart of N2 switching in an embodiment of the present invention;

FIG3 is a schematic diagram of an XN switching networking architecture in an embodiment of the present invention;

FIG. 4 is a flow chart of XN switching in an embodiment of the present invention.

Detailed ways

In order to make the technical solution, the technical problem solved and the technical effect of the present invention more clearly understood, the technical solution of the present invention is clearly and completely described below in conjunction with specific embodiments.

The English words in the attached drawings are now explained:

UE, the full name of which is User Equipment, refers to the terminal device that can access the network in the 5G network.

NG-RAN, the full name of which is Next Generation Radio Access Network, is the wireless access network in the 5G system and is named by the 3GPP standardization organization.

UPF, the full name of User Plane Function, is an important part of the 5G core network, mainly responsible for processing and managing the routing and forwarding of user data packets. UPF also includes functions such as data interaction with external data networks, QoS (Quality of Service) processing of the user plane, and implementation of flow control rules. These functions ensure the effective transmission of data and the effective use of network resources.

DN, the full name of Data Network, refers to the target network that the user equipment (UE) wants to access, which can be the Internet, the operator's business network, or the service network provided by a third party. The data network can be any type of network as long as it can connect to the UPF and exchange data.

AMF, the full name of which is Access and Mobility Management Function, is a functional entity responsible for access and mobility management in the 5G network, and is responsible for processing user access requests, mobility management, security authentication and other functions. Specifically, the main responsibilities of AMF include: ① Access control: AMF is responsible for processing access requests from user equipment (UE) to ensure that only authorized devices can access the network; ② Mobility management: AMF tracks and manages the location information of UE, and maintains the stability of the connection during the movement of UE; ③ Security authentication: AMF is also responsible for authenticating and encrypting user equipment to ensure the security of communications.

Embodiment 1:

This embodiment proposes a service continuity method for offloading gateway change, which is applied under the 5G core network architecture and uses the 5G core network switching signaling.

The diversion gateway is deployed between the base station and the core network. The function of the diversion gateway is to divert local business traffic and central business traffic. When the terminal device UE first accesses NG-RAN, the diversion gateway identifies the UE IP address, AMF-UE-NGAP-ID, RAN-UE-NGAP-ID, N3 GTPU tunnel and other information based on the N2 signaling and N3 data packets and stores the association relationship. The uplink data is distinguished as local or central according to the pre-configured routing rules of the diversion gateway. The data diversion gateway to the local will strip the GTPU header information carried by the base station and forward it to the local DN. If the data is to the central computer room, it will be forwarded directly to the central UPF.

With reference to Figures 1-4, when performing local services, the movement of the terminal causes the base station and the offload gateway to change. At this time:

When the N2 switching process causes the offload gateway to change, the source offload gateway actively sends the UE IP address and GTPU tunnel information to the target offload gateway to complete the association of user information, and actively sends simulated data packets to update DN routing information to ensure business continuity;

When the XN switching process causes the offload gateway to change, the target offload gateway initiates the UE IP address and GTPU tunnel information acquisition to the source offload gateway through the SourceAMF_UE_NGAP_ID field, and then associates it with the user information and updates the local DN routing information to ensure business continuity.

N2 switching refers to the process of a mobile device switching from a 4G network to a 5G network, especially under the 5G non-standalone (NSA) network architecture.

In conjunction with FIG. 2 , in this embodiment, when the N2 switching process causes the offload gateway to change,

The source offload gateway discovers the target base station by identifying the Handover Required signaling, and identifies the UE-associated GTPU tunnel information and UE IP address;

Through the source offload gateway information associated with the locally configured target base station, the UE IP address and GTPU tunnel are sent to the target offload gateway through the Agent of the source offload gateway;

After receiving the information, the target offload gateway identifies the user information through the Handover Command and Handover Complete information, and associates the latest information with the received downlink GTPU tunnel information and UE IP address, thereby establishing a new relationship;

After the relationship is established, the target offload gateway simulates the uplink data packet and forwards it to the DN. The routing information of the DN is changed to the target offload gateway, and subsequent data is transmitted to the target base station and terminal device UE through the target offload gateway.

XN handover, where the role of the XN interface: In the 5G network, the XN interface (or Xn interface) is an interface connecting different base stations, which is used to support the handover of user equipment (UE) during movement. When the UE moves from one base station service area to another base station service area, XN handover is required to ensure service continuity. XN handover process: The process of XN handover is similar to X2 handover in 4G LTE. When the UE moves and needs to switch to a new base station, the source base station will initiate a handover request and communicate with the target base station through the XN interface. After confirming that it can serve the UE, the target base station will send an RRC reconfiguration message to the UE, containing the necessary information of the new cell. The UE completes the handover to the new base station based on this information and sends an RRC reconfiguration completion message to confirm that the handover is complete. When the XN handover process causes a change in the offload gateway, although the UPF (user plane function) may not change, in some cases, if the new base station is connected to a different UPF or needs to route data through a different path, then a change in the offload gateway may occur. This change is to ensure that the data stream can be effectively transmitted to the correct destination while maintaining the performance and stability of the network.

In conjunction with FIG. 4 , in this embodiment, when the XN switching process causes the distribution gateway to change,

The target offload gateway obtains SourceAMF_UE_NGAP_ID information based on the received Path Switch Request, queries the source offload gateway information locally, and forwards this information to the source offload gateway through the Agent;

After receiving the data packet, the source offload gateway queries the UE context information and forwards the UE-associated information including the GTPU tunnel information and the UE IP address to the target offload gateway;

The target offload gateway learns the latest tunnel information based on Path Switch Request and Path Switch Request Ack and associates it with the information obtained from the source offload gateway to establish a new relationship;

After the relationship is established, the target offload gateway simulates the uplink data packet and forwards it to the DN. The routing information of the DN is changed to the target offload gateway, and subsequent data is transmitted to the target base station and terminal device UE through the target offload gateway.

Embodiment 2:

In conjunction with Figures 1-4, this embodiment proposes a service continuity system for changing a diversion gateway, which is applied under a 5G core network architecture, with the help of 5G core network switching signaling, and its implementation process involves a source diversion gateway and a target diversion gateway, wherein:

When the N2 switching process causes the offload gateway to change, the source offload gateway actively sends the UE IP address and GTPU tunnel information to the target offload gateway to complete the association of user information, and actively sends simulated data packets to update DN routing information to ensure business continuity;

When the XN switching process causes the offload gateway to change, the target offload gateway initiates the UE IP address and GTPU tunnel information acquisition to the source offload gateway through the SourceAMF_UE_NGAP_ID field, and then associates it with the user information and updates the local DN routing information to ensure business continuity.

It should be added that the diversion gateway is deployed between the base station and the core network. The function of the diversion gateway is to divert local business traffic and central business traffic. When the terminal device UE first accesses NG-RAN, the diversion gateway identifies the UE IP address, AMF-UE-NGAP-ID, RAN-UE-NGAP-ID, N3 GTPU tunnel and other information based on N2 signaling and N3 data packets and stores the association relationship. The uplink data is distinguished as local or central according to the pre-configured routing rules of the diversion gateway. The data diversion gateway to the local will strip the GTPU header information carried by the base station and forward it to the local DN. If the data is to the central computer room, it will be forwarded directly to the central UPF.

When performing local services, terminal movement causes changes in base stations and offload gateways.

N2 switching refers to the process of a mobile device switching from a 4G network to a 5G network, especially under the 5G non-standalone (NSA) network architecture.

In conjunction with FIG. 2 , in this embodiment, when the N2 switching process causes the offload gateway to change,

The source offload gateway discovers the target base station by identifying the Handover Required signaling, and identifies the UE-associated GTPU tunnel information and UE IP address;

Through the source offload gateway information associated with the locally configured target base station, the UE IP address and GTPU tunnel are sent to the target offload gateway through the Agent of the source offload gateway;

After receiving the information, the target offload gateway identifies the user information through the Handover Command and Handover Complete information, and associates the latest information with the received downlink GTPU tunnel information and UE IP address, thereby establishing a new relationship;

After the relationship is established, the target offload gateway simulates the uplink data packet and forwards it to the DN. The routing information of the DN is changed to the target offload gateway, and subsequent data is transmitted to the target base station and terminal device UE through the target offload gateway.

XN handover, where the role of the XN interface: In the 5G network, the XN interface (or Xn interface) is an interface connecting different base stations, which is used to support the handover of user equipment (UE) during movement. When the UE moves from one base station service area to another base station service area, XN handover is required to ensure service continuity. XN handover process: The process of XN handover is similar to X2 handover in 4G LTE. When the UE moves and needs to be handed over to a new base station, the source base station will initiate a handover request and communicate with the target base station through the XN interface. After confirming that it can serve the UE, the target base station will send an RRC reconfiguration message to the UE, containing the necessary information of the new cell. The UE completes the handover to the new base station based on this information and sends an RRC reconfiguration completion message to confirm that the handover is complete. When the XN handover process causes a change in the offload gateway, although the UPF (user plane function) may not change, in some cases, if the new base station is connected to a different UPF or needs to route data through a different path, then a change in the offload gateway may occur. This change is to ensure that the data stream can be effectively transmitted to the correct destination while maintaining the performance and stability of the network.

In conjunction with FIG. 4 , in this embodiment, when the XN switching process causes the distribution gateway to change,

The target offload gateway obtains SourceAMF_UE_NGAP_ID information based on the received Path Switch Request, queries the source offload gateway information locally, and forwards this information to the source offload gateway through the Agent;

After receiving the data packet, the source offload gateway queries the UE context information and forwards the UE-associated information including the GTPU tunnel information and the UE IP address to the target offload gateway;

The target offload gateway learns the latest tunnel information based on Path Switch Request and Path Switch Request Ack and associates it with the information obtained from the source offload gateway to establish a new relationship;

After the relationship is established, the target offload gateway simulates the uplink data packet and forwards it to the DN. The routing information of the DN is changed to the target offload gateway, and subsequent data is transmitted to the target base station and terminal device UE through the target offload gateway.

In summary, the service continuity method and system for changing a diversion gateway of the present invention can ensure that the diversion gateway is switched during service forwarding without service interruption or reduce the service interruption time.

The above specific examples are used to explain the principles and implementation methods of the present invention in detail. These examples are only used to help understand the core technical content of the present invention. Based on the above specific embodiments of the present invention, any improvements and modifications made by technicians in this technical field without departing from the principles of the present invention should fall within the scope of patent protection of the present invention.

Claims (10)

1. A service continuity method for offloading gateway change, characterized in that the method is applied under the 5G core network architecture, using the 5G core network switching signaling, When the N2 switching process causes the offload gateway to change, the source offload gateway actively sends the UE IP address and GTPU tunnel information to the target offload gateway to complete the association of user information, and actively sends simulated data packets to update DN routing information to ensure business continuity; When the XN switching process causes the offload gateway to change, the target offload gateway initiates the UE IP address and GTPU tunnel information acquisition to the source offload gateway through the SourceAMF_UE_NGAP_ID field, and then associates it with the user information and updates the local DN routing information to ensure business continuity. 2. A method for business continuity of offload gateway change according to claim 1, characterized in that when the offload gateway is changed during the N2 switching process, The source offload gateway searches for the locally configured target gateway information through the target base station information in the handover request, and proactively forwards the user UE IP and GTPU tunnel information to the target offload gateway; After the target offload gateway receives the message, it associates the downlink GTPU tunnel information with the latest tunnel information to establish a new relationship; After the relationship is established, the upstream data packet is simulated to complete the path update. 3. A method for business continuity of offload gateway change according to claim 2, characterized in that when the offload gateway is changed during the N2 switching process, The source offload gateway discovers the target base station by identifying the Handover Required signaling, and identifies the UE-associated GTPU tunnel information and UE IP address; Through the source offload gateway information associated with the locally configured target base station, the UE IP address and GTPU tunnel are sent to the target offload gateway through the Agent of the source offload gateway; After receiving the information, the target offload gateway identifies the user information through the Handover Command and Handover Complete information, and associates the latest information with the received downlink GTPU tunnel information and UE IP address; The target offload gateway simulates the uplink data packet and forwards it to the DN. The routing information of the DN is changed to the target offload gateway, and subsequent data is transmitted to the target base station and terminal through the target offload gateway. 4. A method for business continuity of offloading gateway change according to claim 3, characterized in that when the offloading gateway is changed during the XN switching process, The target base station uses the SourceAMF_UE_NGAP_ID field to index the user information to the source offload gateway, and after completing the data acquisition, associates the latest GTPU tunnel information through the UE IP address to establish a new relationship; After the relationship is established, the upstream data packet is simulated to complete the path update. 5. A method for business continuity of offloading gateway change according to claim 4, characterized in that when the offloading gateway is changed during the XN switching process, The target offload gateway obtains SourceAMF_UE_NGAP_ID information based on the received Path Switch Request, queries the source offload gateway information locally, and forwards this information to the source offload gateway through the Agent; After receiving the data packet, the source offload gateway queries the UE context information and forwards the UE-associated information including the GTPU tunnel information and the UE IP address to the target offload gateway; The target offload gateway learns the latest tunnel information based on Path Switch Request and Path Switch Request Ack and associates it with the information obtained from the source offload gateway; The target offload gateway simulates the uplink data packet and forwards it to the DN. The routing information of the DN is changed to the target offload gateway, and subsequent data is transmitted to the target base station and terminal through the target offload gateway. 6. A business continuity system for changing a diversion gateway, characterized in that it is applied under a 5G core network architecture, with the help of 5G core network switching signaling, and its implementation process involves a source diversion gateway and a target diversion gateway, wherein: When the N2 switching process causes the offload gateway to change, the source offload gateway actively sends the UE IP address and GTPU tunnel information to the target offload gateway to complete the association of user information, and actively sends simulated data packets to update DN routing information to ensure business continuity; When the XN switching process causes the offload gateway to change, the target offload gateway initiates the UE IP address and GTPU tunnel information acquisition to the source offload gateway through the SourceAMF_UE_NGAP_ID field, and then associates it with the user information and updates the local DN routing information to ensure business continuity. 7. A business continuity system for offloading gateway change according to claim 6, characterized in that when the offloading gateway is changed during the N2 switching process, The source offload gateway searches for the locally configured target gateway information through the target base station information in the handover request, and proactively forwards the user UE IP and GTPU tunnel information to the target offload gateway; After the target offload gateway receives the message, it associates the downlink GTPU tunnel information with the latest tunnel information to establish a new relationship; After the relationship is established, the upstream data packet is simulated to complete the path update. 8. A business continuity system for offloading gateway change according to claim 7, characterized in that when the offloading gateway is changed during the N2 switching process, The source offload gateway discovers the target base station by identifying the Handover Required signaling, and identifies the UE-associated GTPU tunnel information and UE IP address; Through the source offload gateway information associated with the locally configured target base station, the UE IP address and GTPU tunnel are sent to the target offload gateway through the Agent of the source offload gateway; After receiving the information, the target offload gateway identifies the user information through the Handover Command and Handover Complete information, and associates the latest information with the received downlink GTPU tunnel information and UE IP address; The target offload gateway simulates the uplink data packet and forwards it to the DN. The routing information of the DN is changed to the target offload gateway, and subsequent data is transmitted to the target base station and terminal through the target offload gateway. 9. A business continuity system for offloading gateway change according to claim 8, characterized in that when the offloading gateway is changed during the XN switching process, The target base station uses the SourceAMF_UE_NGAP_ID field to index the user information to the source offload gateway, and after completing the data acquisition, associates the latest GTPU tunnel information through the UE IP address to establish a new relationship; After the relationship is established, the upstream data packet is simulated to complete the path update. 10. A business continuity system for offloading gateway change according to claim 9, characterized in that when the offloading gateway is changed during the XN switching process, The target offload gateway obtains SourceAMF_UE_NGAP_ID information based on the received Path Switch Request, queries the source offload gateway information locally, and forwards this information to the source offload gateway through the Agent; After receiving the data packet, the source offload gateway queries the UE context information and forwards the UE-associated information including the GTPU tunnel information and the UE IP address to the target offload gateway; The target offload gateway learns the latest tunnel information based on Path Switch Request and Path Switch Request Ack and associates it with the information obtained from the source offload gateway; The target offload gateway simulates the uplink data packet and forwards it to the DN. The routing information of the DN is changed to the target offload gateway, and subsequent data is transmitted to the target base station and terminal through the target offload gateway.