Fault tolerance method and device for user plane function (UPF) fault in communication system

Abstract

The embodiment of the invention provides a fault tolerance method and device for UPF faults in a communication system, and relates to the technical field of core networks, and the method is applied to a first SMF in the communication system. The method comprises the following steps: detecting the state of an associated UPF; the first SMF is associated with at least one UPF, and the communication system comprises a plurality of SMFs; based on the status of the associated UPF, the likelihood that the AMF selects the first SMF is adjusted. On the basis, the possibility of selecting the SMF by the AMF can be automatically adjusted, and the automation of networking disaster recovery is enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of core networks, and in particular, to a fault tolerance method and device for UPF faults in a communication system. Background Art

[0002] When terrestrial operators deploy a 5G core network, in order to improve the reliability and disaster tolerance of the core network, different network topologies are deployed in different regions according to factors such as the coverage area of base stations and geographical administrative regions. Moreover, a single manufacturer is responsible for the construction of a region, and all the core network devices in the network topology of this region are built by this manufacturer. For example, AMF (Access and Mobility Management Function), SMF (Session Management function), UPF (User Plane Function), NRF (Network Repository Function), etc. in the network topology. In different network topologies, by setting specific network configuration information for the UPF in the network topology, the UPF is enabled to support the corresponding network functions. A UE (User Equipment) can establish a session with the UPF according to the network functions supported by the UPF.

[0003] In the related art, when a UE needs to establish a session with a target UPF that supports the target network function, the UE sends a session request message to the AMF. After receiving the session request message, the AMF determines the target SMF corresponding to the target network configuration information indicating the target network function carried in the session request message. Then, the AMF forwards the session request message to the target SMF. After receiving the session request message, the target SMF sends a session request message to the target UPF. Further, the target UPF establishes a session with the UE.

[0004] However, when a UPF in the network topology fails, the AMF still selects the SMF associated with the failed UPF, and it is necessary for technicians to manually adjust the possibility of the AMF selecting the SMF, resulting in poor automation of network topology disaster tolerance. Summary of the Invention

[0005] The purpose of the embodiments of the present invention is to provide a fault tolerance method and device for UPF faults in a communication system, so as to automatically adjust the possibility of the AMF selecting the SMF and enhance the automation of network topology disaster tolerance. The specific technical solutions are as follows:

[0006] In a first aspect, to achieve the above object, an embodiment of the present invention provides a fault tolerance method for a UPF failure in a communication system. The method is applied to a first session management function SMF in the communication system, and the method includes:

[0007] Detect the status of the associated UPF; wherein, the first SMF is associated with at least one UPF, and the communication system includes multiple SMFs;

[0008] Based on the status of the associated UPF, adjust the possibility that the AMF selects the first SMF.

[0009] In a possible embodiment, the communication system further includes: an NRF;

[0010] The adjusting the possibility that the AMF selects the first SMF based on the status of the associated UPF includes:

[0011] In the case of detecting that at least one of the associated UPFs fails, based on the number of the failed associated UPFs, determine the status information of the first SMF; wherein, the status information includes: the capacity information of the first SMF, and / or, the load information; send an update message carrying the status information of the first SMF to the NRF.

[0012] In a possible embodiment, the adjusting the possibility that the AMF selects the first SMF based on the status of the associated UPF includes:

[0013] In the case of detecting that at least one of the associated UPFs recovers from a failure, based on the number of the associated UPFs that have recovered from the failure, determine the status information of the first SMF; send an update message carrying the status information of the first SMF to the NRF.

[0014] In a possible embodiment, the communication system further includes: an NRF;

[0015] The adjusting the possibility that the AMF selects the first SMF based on the status of the associated UPF includes:

[0016] In the case of detecting that all the associated UPFs have failed, send an update message indicating that the first SMF is in an unavailable state to the NRF.

[0017] In a possible embodiment, the adjusting the possibility that the AMF selects the first SMF based on the status of the associated UPF includes:

[0018] In the case of detecting that at least one of the associated UPFs recovers from a failure, send an update message indicating that the first SMF is in an available state to the NRF.

[0019] In a possible embodiment, the update message is a TCP message.

[0020] In a possible embodiment, adjusting the possibility that the AMF selects the first SMF based on the status of the associated UPF includes:

[0021] When it is detected that all the associated UPFs have failed, disconnect the communication link with the AMF.

[0022] In a possible embodiment, when it is detected that all the associated UPFs have failed, disconnecting the communication link with the AMF includes:

[0023] When it is detected that all the associated UPFs have failed, send a message for tearing down the communication link to the AMF.

[0024] In a possible embodiment, adjusting the possibility that the AMF selects the first SMF based on the status of the associated UPF includes:

[0025] When it is detected that at least one of the associated UPFs has recovered from a failure, resume the communication link with the AMF.

[0026] In a possible embodiment, when it is detected that at least one of the associated UPFs has recovered from a failure, resuming the communication link with the AMF includes:

[0027] When it is detected that at least one of the associated UPFs has recovered from a failure, send a message for establishing a communication link to the AMF.

[0028] In a possible embodiment, adjusting the possibility that the AMF selects the first SMF based on the status of the associated UPF includes:

[0029] When it is detected that all the associated UPFs have failed, if a session request message sent by the AMF is received, send a session response message carrying an error code to the AMF.

[0030] In a possible embodiment, detecting the status of the associated UPF includes:

[0031] When the time corresponding to the detection period is reached, send a heartbeat detection request message to the associated UPF; for each associated UPF, if the heartbeat detection response message sent by the associated UPF is not received within the first set duration after sending the heartbeat detection request message, determine that the associated UPF has failed; if the heartbeat detection response message sent by the associated UPF is received within the first set duration after sending the heartbeat detection request message, determine that the associated UPF is in a normal state or has recovered from a failure.

[0032] In a possible embodiment, the detecting the state of the associated UPF includes:

[0033] When the time corresponding to the detection period is reached, send a heartbeat detection request message to the associated UPF; for each associated UPF, if the heartbeat detection response message sent by the associated UPF is not received after continuously sending the heartbeat detection request message to the associated UPF for multiple detection periods, determine that the associated UPF has failed; if the heartbeat detection response message sent by the associated UPF is received within the first set duration after sending the heartbeat detection request message, determine that the associated UPF is in a normal state or has recovered from a failure.

[0034] In a second aspect, to achieve the above object, an embodiment of the present invention provides a fault tolerance method for UPF faults in a communication system, where the method is applied to an AMF in the communication system, and the method includes:

[0035] Receive an update message carrying the state of the first SMF, where the state of the first SMF is related to the state of the UPF associated with the first SMF;

[0036] According to the received update message, update the state of the first SMF recorded locally to adjust the possibility of the AMF selecting the first SMF.

[0037] In a possible embodiment, the receiving an update message carrying the state of the first SMF includes:

[0038] Receive an update message carrying the state information of the first SMF sent by the NRF; where the state information includes: the capacity information of the first SMF, and / or, the load information;

[0039] The updating the state of the first SMF recorded locally according to the received update message includes:

[0040] Update the state information of the first SMF recorded locally.

[0041] In a possible embodiment, the receiving an update message carrying the state of the first SMF includes:

[0042] Receive an update message sent by the NRF indicating that the first SMF is in an unavailable state;

[0043] Updating the state of the first SMF recorded locally according to the received update message includes:

[0044] Update the state of the first SMF recorded locally to an unavailable state.

[0045] In a possible embodiment, receiving the update message carrying the state of the first SMF includes:

[0046] Receive an update message sent by the NRF indicating that the first SMF is in an available state;

[0047] Updating the state of the first SMF recorded locally according to the received update message includes:

[0048] Update the state of the first SMF recorded locally to an available state.

[0049] In a possible embodiment, the method further includes:

[0050] If a response message sent by the first SMF is not received within a first set duration after sending a request message to the first SMF, update the state of the first SMF recorded locally to an unavailable state; wherein, the request message includes a heartbeat detection request message, and / or, a session request message.

[0051] In a possible embodiment, the method further includes:

[0052] If a response message sent by the first SMF is received within a first set duration after sending a request message to the first SMF, update the state of the first SMF recorded locally to an available state.

[0053] In a possible embodiment, the method further includes:

[0054] If a message for tearing down a communication link sent by the first SMF is received, update the state of the first SMF recorded locally to an unavailable state.

[0055] In a possible embodiment, the method further includes:

[0056] If a message for establishing a communication link sent by the first SMF is received, update the state of the first SMF recorded locally to an available state.

[0057] In a possible embodiment, receiving the update message carrying the state of the first SMF includes:

[0058] Receive a session response message carrying an error code sent by the first SMF;

[0059] Updating the status of the first SMF recorded locally according to the received update message includes:

[0060] Count the number of session response messages carrying error codes received within a second set duration; when the counted number is greater than a first number, update the status of the first SMF recorded locally to an unavailable state.

[0061] In a possible embodiment, after updating the status of the first SMF recorded locally to an unavailable state, the method further includes:

[0062] When a third set duration is reached, update the status of the first SMF recorded locally to an available state.

[0063] In a third aspect, to achieve the above object, an embodiment of the present invention provides a fault tolerance device for UPF faults in a communication system. The device is applied to a first SMF in the communication system, and the device includes:

[0064] A detection module for detecting the status of an associated UPF; wherein, the first SMF is associated with at least one UPF, and the communication system includes multiple SMFs;

[0065] An adjustment module for adjusting the possibility of the AMF selecting the first SMF based on the status of the associated UPF.

[0066] In a possible embodiment, the communication system further includes: an NRF;

[0067] The adjustment module is specifically configured to, in the case of detecting that at least one of the associated UPFs fails, determine status information of the first SMF based on the number of the associated UPFs that have failed; wherein, the status information includes: capacity information of the first SMF, and / or, load information; send an update message carrying the status information of the first SMF to the NRF.

[0068] In a possible embodiment, the adjustment module is specifically configured to, in the case of detecting that at least one of the associated UPFs recovers from a fault, determine status information of the first SMF based on the number of the associated UPFs that have recovered from the fault; send an update message carrying the status information of the first SMF to the NRF.

[0069] In a possible embodiment, the communication system further includes: an NRF;

[0070] The adjustment module is specifically configured to send an update message indicating that the first SMF is in an unavailable state to the NRF when it is detected that all the associated UPFs have failed.

[0071] In a possible embodiment, the adjustment module is specifically configured to send an update message indicating that the first SMF is in an available state to the NRF when it is detected that at least one of the associated UPFs has recovered from a failure.

[0072] In a possible embodiment, the update message is a TCP message.

[0073] In a possible embodiment, the adjustment module is specifically configured to disconnect the communication link with the AMF when it is detected that all the associated UPFs have failed.

[0074] In a possible embodiment, the adjustment module is specifically configured to send a message for tearing down the communication link to the AMF when it is detected that all the associated UPFs have failed.

[0075] In a possible embodiment, the adjustment module is specifically configured to restore the communication link with the AMF when it is detected that at least one of the associated UPFs has recovered from a failure.

[0076] In a possible embodiment, the adjustment module is specifically configured to send a message for establishing the communication link to the AMF when it is detected that at least one of the associated UPFs has recovered from a failure.

[0077] In a possible embodiment, the adjustment module is specifically configured to, when it is detected that all the associated UPFs have failed and a session request message sent by the AMF is received, send a session response message carrying an error code to the AMF.

[0078] In a possible embodiment, the detection module is specifically configured to send a heartbeat detection request message to the associated UPF at the moment corresponding to the detection period; for each associated UPF, if a heartbeat detection response message sent by the associated UPF is not received within a first set duration after sending the heartbeat detection request message, determine that the associated UPF has failed; if a heartbeat detection response message sent by the associated UPF is received within a first set duration after sending the heartbeat detection request message, determine that the associated UPF has recovered from a failure.

[0079] In a possible embodiment, the detection module is specifically configured to send a heartbeat detection request message to the associated UPF at the moment corresponding to the detection period; for each associated UPF, if no heartbeat detection response message sent by the associated UPF is received after sending the heartbeat detection request message to the associated UPF for a continuous plurality of detection periods, it is determined that the associated UPF has failed; if a heartbeat detection response message sent by the associated UPF is received within a first set duration after sending the heartbeat detection request message, it is determined that the failure of the associated UPF has been recovered.

[0080] Fourthly, to achieve the above object, an embodiment of the present invention provides a fault tolerance device for a UPF failure in a communication system. The device is applied to the AMF in the communication system, and the device includes:

[0081] An update message receiving module, configured to receive an update message carrying a first SMF state, where the first SMF state is related to the state of the UPF associated with the first SMF;

[0082] A first state update module, configured to update the first SMF state recorded locally according to the received update message, so as to adjust the possibility that the AMF selects the first SMF.

[0083] In a possible embodiment, the update message receiving module is specifically configured to receive an update message carrying the state information of the first SMF sent by the NRF; where the state information includes: the capacity information of the first SMF, and / or, the load information;

[0084] The first state update module is specifically configured to update the state information of the first SMF recorded locally.

[0085] In a possible embodiment, the update message receiving module is specifically configured to receive an update message sent by the NRF indicating that the first SMF is in an unavailable state;

[0086] The first state update module is specifically configured to update the first SMF state recorded locally to an unavailable state.

[0087] In a possible embodiment, the update message receiving module is specifically configured to receive an update message sent by the NRF indicating that the first SMF is in an available state;

[0088] The first state update module is specifically configured to update the first SMF state recorded locally to an available state.

[0089] In a possible embodiment, the device further includes:

[0090] A second status update module, configured to update the status of the first SMF recorded locally to an unavailable status if a response message sent by the first SMF is not received within a first set duration after a request message is sent to the first SMF; wherein, the request message includes a heartbeat detection request message and / or a session request message.

[0091] In a possible embodiment, the apparatus further includes:

[0092] A third status update module, configured to update the status of the first SMF recorded locally to an available status if a response message sent by the first SMF is received within a first set duration after a request message is sent to the first SMF.

[0093] In a possible embodiment, the apparatus further includes:

[0094] A fourth status update module, configured to update the status of the first SMF recorded locally to an unavailable status if a message sent by the first SMF for tearing down a communication link is received.

[0095] In a possible embodiment, the apparatus further includes:

[0096] A fifth status update module, configured to update the status of the first SMF recorded locally to an available status if a message sent by the first SMF for establishing a communication link is received.

[0097] In a possible embodiment, the update message receiving module is specifically configured to receive a session response message carrying an error code sent by the first SMF;

[0098] The first status update module is specifically configured to count the number of session response messages carrying an error code received within a second set duration; and update the status of the first SMF recorded locally to an unavailable status when the counted number is greater than a first number.

[0099] In a possible embodiment, the apparatus further includes:

[0100] A sixth status update module, configured to, after the first status update module executes the operation of updating the status of the first SMF recorded locally to an unavailable status, update the status of the first SMF recorded locally to an available status when a third set duration is reached.

[0101] An embodiment of the present disclosure further provides an electronic device, including a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus;

[0102] A memory for storing computer programs;

[0103] A processor, when executing the program stored in the memory, implements the steps of the fault tolerance method for UPF faults in any of the above-mentioned communication systems.

[0104] The embodiments of the present disclosure also provide a computer-readable storage medium, in which a computer program is stored, and when the computer program is executed by a processor, the steps of the fault tolerance method for UPF faults in any of the above-mentioned communication systems are implemented.

[0105] The embodiments of the present invention also provide a computer program product containing instructions, which, when running on a computer, causes the computer to execute the fault tolerance method for UPF faults in any of the above-mentioned communication systems.

[0106] Advantages of the embodiments of the present invention:

[0107] A fault tolerance method and device for UPF faults in a communication system provided by the embodiments of the present invention are applied to the first SMF in the communication system. The method includes: detecting the status of the associated UPF; wherein, the first SMF is associated with at least one UPF, and the communication system includes multiple SMFs; based on the status of the associated UPF, adjusting the possibility of the AMF selecting the first SMF. Based on this, it is possible to automatically adjust the possibility of the AMF selecting the SMF, enhancing the automation of network disaster tolerance.

[0108] Of course, when implementing any product or method of the present invention, it is not necessarily required to achieve all the above-mentioned advantages at the same time. Description of the Drawings

[0109] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention, and those of ordinary skill in the art can also obtain other embodiments based on these drawings.

[0110] Figure 1 A structural diagram of a core network provided by the embodiments of the present invention;

[0111] Figure 2 A flowchart of the first fault tolerance method for UPF faults in a communication system provided by the embodiments of the present invention;

[0112] Figure 3 A flowchart of the second fault tolerance method for UPF faults in a communication system provided by the embodiments of the present invention;

[0113] Figure 4Flowchart of the third fault tolerance method for UPF faults in the communication system provided by the embodiments of the present invention;

[0114] Figure 5 Flowchart of the fourth fault tolerance method for UPF faults in the communication system provided by the embodiments of the present invention;

[0115] Figure 6 Flowchart of the fifth fault tolerance method for UPF faults in the communication system provided by the embodiments of the present invention;

[0116] Figure 7 Flowchart of the sixth fault tolerance method for UPF faults in the communication system provided by the embodiments of the present invention;

[0117] Figure 8 Flowchart of the seventh fault tolerance method for UPF faults in the communication system provided by the embodiments of the present invention;

[0118] Figure 9 Flowchart of the eighth fault tolerance method for UPF faults in the communication system provided by the embodiments of the present invention;

[0119] Figure 10 Flowchart of the ninth fault tolerance method for UPF faults in the communication system provided by the embodiments of the present invention;

[0120] Figure 11 Structural diagram of the fault tolerance device for UPF faults in the first communication system provided by the embodiments of the present invention;

[0121] Figure 12 Structural diagram of the fault tolerance device for UPF faults in the second communication system provided by the embodiments of the present invention;

[0122] Figure 13 Structural diagram of an electronic device provided by the embodiments of the present invention. Detailed implementation manners

[0123] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art based on the present invention belong to the scope of protection of the present invention.

[0124] In the 3GPP standard, for the reliability issue of core network devices in 5G deployment, a deployment solution with a relevant NF Set (Network Function Set) (such as POOL networking) is adopted. To improve the reliability and disaster recovery ability of the core network, different network deployments are carried out in different regions according to factors such as the base station coverage area and geographical administrative region division. Moreover, the core network devices of the network deployment in one region are built by a single manufacturer, and the main core network devices in this region are all built by this manufacturer. The base stations covering this region are only connected to the core network devices deployed in this region.

[0125] Although the 3GPP standard defines that each service-oriented interface and standard interface of 5G core network devices are open standard interfaces, in actual deployment, due to manufacturer implementation issues, it is very difficult to achieve seamless docking between core network devices of different manufacturers. For example, considering the interface maturity, the N16 interface between AMF and SMF has a high fault tolerance and a greater possibility of being open, but the N4 interface between SMF and UPF is generally privately customized and difficult to open. Once there is a disaster recovery situation of core network devices of multiple manufacturers in different locations, the currently defined protocol seems inadequate. This is also the reason why, when deploying core network devices on the ground, it is inclined to deploy the network in the same region according to the same manufacturer to minimize the docking between core network devices of different manufacturers.

[0126] However, some mobile private networks adopt a centralized deployment method. At the same time, due to the requirement for reliability and disaster recovery, it is required that the core network devices be deployed with different network deployments in different regions to support disaster recovery in different locations. Moreover, due to the particularity of base station coverage in some mobile private networks, the corresponding core network devices adopt a centralized deployment method. At the same time, considering the reliability of core network devices, a multi-center and multi-vendor deployment method may also be adopted, that is, different network deployments are carried out in multiple regions, and the core network devices of different centers use core network devices of different manufacturers.

[0127] However, in the network deployment in the above - mentioned manner, the core network devices in different networks come from different manufacturers, and not all interfaces between different manufacturers are fully open. Except for the core network devices with the determined open interfaces, other core network devices need to manually switch the SMF selection algorithm. For example, when all UPFs in a network fail, the connected SMF cannot forward the session request message to the failed UPF. Even if the SMF itself has not failed, the SMF is still in an unavailable state. However, the AMF in this network will still select the unavailable SMF in this network, and it needs to be manually adjusted by technicians to make the AMF select an available SMF. When some UPFs in this network fail, only by manually adjusting the parameters of the SMF can the selection algorithm of the AMF be affected so that the AMF selects an available SMF. It can be seen that in the related art, it is necessary to manually adjust to make the AMF select an available SMF, resulting in poor automation of network disaster tolerance.

[0128] Exemplarily, refer to Figure 1 , Figure 1 which is a structural diagram of a core network provided by an embodiment of the present invention. The core network includes two networks. Figure 1 The site 1 and site 2 in

[0129] respectively represent two different networks. The base station communicates with different networks through the bearer network. When a network includes UDM (Unified Data Management), PCF (Policy Control function), AMF, SMF, and UPF, this network is a 5G core network, abbreviated as 5GC. When a network includes HSS (Home Subscriber Server), PCF, AMF, SMF, and UPF, the core network is a 4G core network, abbreviated as IMS (IP Multimedia Subsystem).

[0130] To solve the above problems, refer to Figure 2 , Figure 2 which is a flowchart of a fault - tolerance method for UPF failure in a communication system provided by an embodiment of the present invention. This method is applied to the first SMF in the communication system. The communication system can be Figure 1 the core network shown in

[0131] S201: Detect the status of the associated UPF.

[0132] Among them, the first SMF is associated with at least one UPF, and the communication system includes multiple SMFs.

[0133] S202: Based on the status of the associated UPF, adjust the possibility of the AMF selecting the first SMF.

[0134] Based on the UPF fault tolerance method in the communication system provided by the embodiments of the present invention, it is possible to automatically adjust the possibility of the AMF selecting the SMF, enhancing the automation of network disaster tolerance.

[0135] Regarding step S201, the core network includes multiple network deployments. One network deployment includes network elements such as AMF, NRF, SMF, and UPF. The first SMF in the embodiments of the present invention is any SMF in the network deployment.

[0136] After the network deployment is completed, the SMF sends a registration request message to the NRF. The registration request message carries the network configuration information corresponding to the SMF. The NRF locally records the correspondence between the SMF and the network configuration information. The correspondence between one SMF and one network configuration information means that the SMF is associated with the UPF having the network configuration information. A UPF having network configuration information means that the UPF supports the corresponding network function.

[0137] The network configuration information includes: network slice information of the network functions supported by the UPF, and / or DNN (Data Network Name).

[0138] The network slice information of the network functions supported by the UPF represents the network slice to which the UPF belongs. The network slice technology can realize flexible allocation of network resources and on-demand combination of network capabilities. Based on a 5G network, multiple network slices with different characteristics can be virtualized. Each network slice is composed of a core network, a radio network, and a transmission network. The network slice can provide multi-level isolation and security, reducing the network construction cost of the operator.

[0139] The DNN of the network functions supported by the UPF represents the private network to which the UPF belongs. The DNN is the identifier of the 5G private network. The terminal used by the user accesses the 5G mobile core network through the UPF in the private network represented by the DNN, which can isolate the access channel of the private network from the public network, thus ensuring the security of network access and the privacy of data transmission. The DNN supports the independent deployment and selection of the UPF. It can be considered that the DNN is the "slicing" technology from the mobile core network to the private network.

[0140] The AMF sends a subscription request message to the NRF, and the network configuration information requested by the AMF is carried in the subscription request message. After receiving the subscription request message, the NRF determines the SMF corresponding to the network configuration information requested by the AMF based on the correspondence between the SMF and the network configuration information recorded locally, and records the correspondence between the AMF and the SMF locally. The correspondence between an AMF and an SMF means that the AMF subscribes to the SMF.

[0141] Moreover, the NRF can also send the identifier of the determined SMF to the AMF. The identifier of the SMF can be a number pre-assigned to the SMF, or the identifier of the SMF can be the IP (Internet Protocol) address of the SMF. Correspondingly, the AMF records the identifier and status of the subscribed SMF locally. The SMF status indicates that the SMF is in an available state or the SMF is in an unavailable state. After the networking deployment is completed, the initial state of each SMF is available.

[0142] Since the status of the first SMF will change, the first SMF detects the status of the associated UPF and updates the status of the first SMF recorded by the AMF based on the status of the associated UPF.

[0143] The first SMF can detect the status of the associated UPF in the following manner.

[0144] Method 1:

[0145] In a possible embodiment, step S201 may include the following steps: at the moment corresponding to the detection period, send a heartbeat detection request message to the associated UPF. For each associated UPF, if the heartbeat detection response message sent by the associated UPF is not received within the first set duration after sending the heartbeat detection request message, it is determined that the associated UPF has failed. If the heartbeat detection response message sent by the associated UPF is received within the first set duration after sending the heartbeat detection request message, it is determined that the associated UPF is in a normal state or the fault has been recovered.

[0146] When the first SMF reaches the moment corresponding to the detection period, it sends a heartbeat detection request message to the associated UPF. The heartbeat detection request message can be a PFCP (Packet Forwarding Control Protocol) message. When the associated UPF fails, the associated UPF cannot respond to the heartbeat detection request message sent by the first SMF. Correspondingly, if the heartbeat detection response message sent by the associated UPF is not received within the first set duration after sending the heartbeat detection request message, the first SMF can determine that the associated UPF has failed.

[0147] If a heartbeat detection response message sent by the associated UPF is received within the first set duration after the heartbeat detection request message is sent, and the associated UPF has not been detected to have failed before, it is determined that the associated UPF is in a normal state. When the failure of the associated UPF is recovered, the associated UPF sends a heartbeat detection response message to the first SMF. Correspondingly, if a heartbeat detection response message sent by the associated UPF is received within the first set duration after the heartbeat detection request message is sent, and the associated UPF has been detected to have failed before, the first SMF can determine that the failure of the associated UPF is recovered.

[0148] The first set duration can be set based on the duration of the detection period and actual requirements. When it is necessary to timely sense the state of the associated UPF, the first set duration can be set to a shorter duration.

[0149] Method 2:

[0150] In a possible embodiment, step S201 may include the following steps: At the moment corresponding to the detection period, a heartbeat detection request message is sent to the associated UPF. For each associated UPF, if the heartbeat detection response message sent by the associated UPF is not received after the heartbeat detection request message is continuously sent to the associated UPF for multiple detection periods, it is determined that the associated UPF has failed. If a heartbeat detection response message sent by the associated UPF is received within the first set duration after the heartbeat detection request message is sent, it is determined that the associated UPF is in a normal state or the failure is recovered.

[0151] After the first SMF sends a heartbeat detection request message to the associated UPF at the moment corresponding to the detection period, the associated UPF may not be able to respond to the heartbeat detection request message sent by the first SMF due to other factors (such as network delay, etc.). It is less accurate to determine that the associated UPF has failed only based on the fact that the associated UPF does not respond to the heartbeat detection request message of the first SMF in one detection period. The first SMF can continue to send a heartbeat detection request message to the associated UPF at the moment corresponding to the detection period. If the heartbeat detection response message sent by the associated UPF is not received after the heartbeat detection request message is continuously sent to the associated UPF for multiple detection periods, the first SMF can determine that the associated UPF has failed. The number of multiple detection periods can be set according to actual requirements. When it is necessary to timely obtain the state of the associated UPF, the number of multiple detection periods can be set to a smaller value, for example, 2.

[0152] If a heartbeat detection response message sent by the associated UPF is received within the first set duration after sending the heartbeat detection request message, and the associated UPF has not been detected to have failed before, it is determined that the associated UPF is in a normal state. When the failure of the associated UPF is recovered, the associated UPF sends a heartbeat detection response message to the first SMF. Correspondingly, if a heartbeat detection response message sent by the associated UPF is received within the first set duration after sending the heartbeat detection request message, and the associated UPF has been detected to have failed before, the first SMF can determine that the failure of the associated UPF is recovered.

[0153] For step S202, after detecting the state of the associated UPF of the first SMF, the first SMF can update the state of the first SMF recorded locally by the AMF based on the state of the associated UPF. Subsequently, when the AMF receives a session request message and selects an SMF based on the updated states of each SMF, it can adjust the possibility of the AMF selecting the first SMF.

[0154] Method 1:

[0155] When it is detected that some of the associated UPFs have failed, the first SMF can process them in the following manner.

[0156] In a possible embodiment, the communication system further includes: NRF; on the basis of Figure 2 refer to Figure 3 , step S202 may include the following steps:

[0157] S2021: When it is detected that at least one of the associated UPFs has failed, determine the state information of the first SMF based on the number of the failed associated UPFs.

[0158] Wherein, the state information includes: the capacity information of the first SMF, and / or, the load information.

[0159] S2022: Send an update message carrying the state information of the first SMF to the NRF.

[0160] There are multiple associated UPFs of the first SMF. When at least one of the associated UPFs fails, the state information of the first SMF will change. Therefore, when it is detected that at least one of the associated UPFs has failed, the first SMF determines the state information of the first SMF based on the number of the failed associated UPFs.

[0161] In one implementation, the status information includes the capacity information of the first SMF. The first SMF determines the number of associated UPFs that have not failed based on the number of associated UPFs that have failed, and uses it as the capacity information of the first SMF. The larger the capacity information of the first SMF, the fewer the number of associated UPFs that have failed, and the more session request messages the first SMF can currently process. When the capacity information of the first SMF is greater than 0, it indicates that the first SMF is in an available state. When the capacity information of the first SMF is 0, it indicates that the first SMF is in an unavailable state.

[0162] In another implementation, the status information includes the load information of the first SMF. The first SMF determines the number of associated UPFs for which sessions have been established, and calculates the ratio of the number of associated UPFs for which sessions have been established to the number of associated UPFs that have not failed, to obtain the load information of the first SMF.

[0163] The first SMF sends an update message carrying the status information of the first SMF to the NRF. The status information includes: the capacity information of the first SMF, and / or, the load information. Correspondingly, the NRF updates the status information of the first SMF recorded locally in the NRF according to the received update message. And, the NRF notifies the AMF to update the status information of the first SMF recorded locally. The processing method of the AMF refers to the relevant introduction in the subsequent embodiments. Subsequently, after receiving the session request message sent by the UE, the AMF selects an SMF based on the updated status information of each SMF, which can realize automatically adjusting the possibility of the AMF selecting the first SMF.

[0164] Method 2:

[0165] When it is detected that some associated UPFs have recovered from a failure, the first SMF can be processed in the following manner.

[0166] In a possible embodiment, based on Figure 2 , referring to Figure 4 , step S202 may include the following steps:

[0167] S2023: When it is detected that at least one associated UPF has recovered from a failure, determine the status information of the first SMF based on the number of associated UPFs that have recovered from the failure.

[0168] S2024: Send an update message carrying the status information of the first SMF to the NRF.

[0169] After a failure occurs in the associated UPF, fault recovery is performed, and the first SMF continues to detect the status of the associated UPF to determine whether the associated UPF has recovered from the fault. Correspondingly, when the first SMF detects that at least one associated UPF has recovered from the fault, it determines the status information of the first SMF based on the number of associated UPFs that have recovered from the fault. The manner of determining the status information of the first SMF refers to the relevant introduction in the foregoing embodiments.

[0170] After the first SMF detects that at least one UPF has recovered from the fault, it sends an update message carrying the status information of the first SMF to the NRF. Correspondingly, the NRF updates the status information of the first SMF recorded locally in the NRF according to the received update message. Moreover, the NRF notifies the AMF to update the status information of the first SMF recorded locally. The processing manner of the AMF refers to the relevant introduction in the subsequent embodiments. Subsequently, after the AMF receives the session request message sent by the UE, it selects an SMF based on the updated status information of each SMF, and can automatically adjust the possibility that the AMF selects the first SMF.

[0171] Method 3:

[0172] When it is detected that all associated UPFs have failed, the first SMF can be processed in the following manner.

[0173] In a possible embodiment, the communication system further includes: NRF. Correspondingly, step S202 may include the following steps: when it is detected that all associated UPFs have failed, send an update message indicating that the first SMF is in an unavailable state to the NRF.

[0174] After the first SMF detects that all associated UPFs have failed, the associated UPF cannot process the session request message. Then the first SMF can update its own status to the unavailable state and send an update message indicating that the first SMF is in the unavailable state to the NRF. For example, the first SMF sends an update message carrying a first preset identifier indicating that the first SMF is in the unavailable state to the NRF.

[0175] The first preset identifier may be Undiscoverable (not discovered), or it may be indicated that the first preset identifier may also be Suspend (suspended).

[0176] Correspondingly, the NRF updates the status of the first SMF recorded locally in the NRF to the unavailable state according to the received update message, and notifies the AMF that subscribes to the first SMF to update the status of the first SMF recorded locally. The processing manner of the AMF refers to the relevant introduction in the subsequent embodiments. Subsequently, after the AMF receives the session request message, it selects an SMF based on the updated status of each SMF, and can automatically adjust the possibility that the AMF selects the first SMF.

[0177] Method 4:

[0178] When it is detected that at least one associated UPF has recovered from a fault, the first SMF may process it in the following manner.

[0179] In a possible embodiment, step S202 may include the following steps: when it is detected that at least one associated UPF has recovered from a fault, send an update message indicating that the first SMF is in an available state to the NRF.

[0180] After updating the state of the first SMF to the unavailable state, when the first SMF detects that at least one associated UPF has recovered from a fault, the recovered associated UPF may process the session request message, then the first SMF may update its own state to the available state and send an update message indicating that the first SMF is in an available state to the NRF. For example, the first SMF sends an update message carrying a second preset identifier indicating that the first SMF is in an available state to the NRF.

[0181] Correspondingly, the NRF updates the state of the first SMF recorded locally in the NRF to the available state according to the received update message, and notifies the AMF subscribing to the first SMF to update the state of the first SMF recorded locally. The processing method of the AMF refers to the relevant introduction in the subsequent embodiments. Subsequently, after receiving the session request message, the AMF selects the SMF based on the updated states of each SMF, which can realize automatically adjusting the possibility that the AMF selects the first SMF.

[0182] In a possible embodiment, the update message sent by the first SMF to the NRF is a TCP (Transmission Control Protocol) message.

[0183] Method 5:

[0184] When it is detected that all associated UPFs have failed, the first SMF may process it in the following manner.

[0185] In a possible embodiment, step S202 may include the following steps: when it is detected that all associated UPFs have failed, disconnect the communication link with the AMF.

[0186] The communication link between the first SMF and the AMF is an HTTP (Hyper Text Transfer Protocol) link. If the first SMF detects that all associated UPFs have failed, the first SMF disconnects the HTTP link with the AMF.

[0187] In one implementation, when it is detected that all associated UPFs have failed, the first SMF sends a message to the AMF for tearing down the communication link. Correspondingly, after receiving this message, the AMF determines to disconnect the communication link with the first SMF and updates the status of the first SMF recorded locally based on this message.

[0188] In another implementation, when the AMF reaches the corresponding moment of the detection period, it sends a heartbeat detection request message to the first SMF. When it is detected that all associated UPFs have failed, the first SMF does not respond to the AMF's heartbeat detection request message. Also, the AMF forwards the session request message to the first SMF after receiving the session request message. Similarly, when it is detected that all associated UPFs have failed, the first SMF does not respond to the AMF's session request message. Correspondingly, the AMF updates the status of the first SMF recorded locally by the AMF based on the situation of the first SMF responding to the request message. The processing method of the AMF refers to the relevant introduction in the subsequent embodiments. Subsequently, after the AMF receives the session request message, it can select the SMF based on the updated statuses of each SMF, which can realize automatically adjusting the possibility of the AMF selecting the first SMF.

[0189] Method 6:

[0190] When it is detected that at least one associated UPF has recovered from the failure, the first SMF can be processed in the following manner.

[0191] In a possible embodiment, step S202 may include the following steps: When it is detected that at least one associated UPF has recovered from the failure, the communication link with the AMF is restored.

[0192] In one implementation, when it is detected that at least one associated UPF has recovered from the failure, the first SMF sends a message to the AMF for establishing a communication link. Correspondingly, after receiving this message, the AMF determines to establish a communication link with the first SMF and updates the status of the first SMF recorded locally based on this message.

[0193] In another implementation, after the first SMF detects that at least one associated UPF has recovered from the failure, if it receives the heartbeat detection request message sent by the AMF, the first SMF sends a corresponding heartbeat detection response message to the AMF. Correspondingly, the AMF updates the status of the first SMF recorded locally by the AMF based on the situation of the first SMF responding to the request message. The processing method of the AMF refers to the relevant introduction in the subsequent embodiments.

[0194] Method 7:

[0195] When it is detected that all associated UPFs have failed, the first SMF can be processed in the following manner.

[0196] In a possible embodiment, step S202 may include the following steps: When it is detected that all associated UPFs have failed, if a session request message sent by the AMF is received, a session response message carrying an error code is sent to the AMF.

[0197] When the UE needs to access the networking of a specified network function, the UE needs to establish a session with the UPF that supports the network function, and then the UE sends a session request message carrying the corresponding network configuration information to the AMF. The network configuration information indicates the network function requested by the UE. Correspondingly, after receiving the session request message of the UE, if the AMF determines that the first SMF is the SMF used to establish a session with the UE, the AMF forwards the session request message to the first SMF.

[0198] After detecting that all associated UPFs have failed, if the first SMF receives a session request message and the associated UPFs are unable to process the session request message, the first SMF sends a session response message carrying an error code to the AMF. Correspondingly, after receiving the session response message sent by the first SMF, the AMF updates the status of the first SMF recorded locally based on the error code carried in the session response message. Subsequently, when the AMF receives a session request message, the AMF selects an SMF based on the updated statuses of each SMF, which can realize automatically adjusting the possibility of the AMF selecting the first SMF.

[0199] See Figure 5 , Figure 5 which is a flowchart of a method for fault tolerance of UPF failures in a communication system provided by an embodiment of the present invention. This method is applied to the AMF in the communication system, and the method may include the following steps:

[0200] S501: Receive an update message carrying the status of the first SMF, where the status of the first SMF is related to the status of the UPFs associated with the first SMF.

[0201] S502: Update the status of the first SMF recorded locally according to the received update message to adjust the possibility of the AMF selecting the first SMF.

[0202] Based on the method for fault tolerance of UPF failures in the communication system provided by the embodiment of the present invention, it is possible to automatically adjust the possibility of the AMF selecting an SMF and enhance the automation of network disaster tolerance.

[0203] The state of the first SMF is related to the state of the UPF associated with the first SMF. For example, when all the UPFs associated with the first SMF fail, even if the SMF does not fail, but the UE and the associated UPF still cannot establish a session through the first SMF, then the first SMF is in an unavailable state. When the UPFs associated with the first SMF are in a normal state or the failures are recovered, the UE and the associated UPF can establish a session through the first SMF, then the first SMF is in an available state.

[0204] The AMF locally records the states of the subscribed SMFs (in this embodiment, the first SMF is taken as an example for illustration). Since the state of the first SMF will change, when the AMF receives an update message indicating the state of the first SMF, indicating that the state of the first SMF has changed, the AMF can update the locally recorded state of the first SMF based on the received update message in the following manner. Subsequently, when the AMF receives a session request message, and selects an SMF based on the updated states of the SMFs, it can adjust the possibility of the AMF selecting the first SMF.

[0205] Method 1:

[0206] In a possible embodiment, step S501 may include the following steps: receiving an update message carried by the NRF with the state information of the first SMF.

[0207] Wherein, the state information includes: the capacity information of the first SMF, and / or, the load information.

[0208] Correspondingly, step S502 may include the following steps: updating the state information of the first SMF recorded locally.

[0209] When the first SMF detects that at least one associated UPF fails, it determines the state information of the first SMF based on the number of the failed associated UPFs. And when the first SMF detects that at least one associated UPF's failure is recovered, it determines the state information of the first SMF based on the number of the associated UPFs whose failures are recovered.

[0210] Then, the first SMF sends an update message carried with the state information of the first SMF to the NRF. The NRF forwards the received update message to the AMF. Correspondingly, when the AMF receives this update message, it determines that the state information of the first SMF has changed, and then updates the state information of the first SMF recorded locally to the state information carried in the update message.

[0211] Method 2:

[0212] In some possible embodiments, step S501 may include the following steps: receiving an update message sent by the NRF indicating that the first SMF is in an unavailable state.

[0213] Correspondingly, step S502 may include the following steps: updating the first SMF status recorded locally to an unavailable status.

[0214] After the first SMF detects that all associated UPFs have failed, it sends an update message indicating that the first SMF is in an unavailable status to the NRF. The NRF forwards this update message to the AMF. Correspondingly, after receiving this update message, if the AMF determines that the first SMF is in an unavailable status, it updates the first SMF status recorded locally to an unavailable status.

[0215] For example, the update message carries a first preset identifier indicating that the first SMF is in an unavailable status. The AMF records the first preset identifier corresponding to the first SMF locally.

[0216] Method 3:

[0217] In a possible embodiment, step S501 may include the following steps: receiving an update message sent by the NRF indicating that the first SMF is in an available status.

[0218] Correspondingly, step S502 may include the following steps: updating the first SMF status recorded locally to an available status.

[0219] After the first SMF is updated to an unavailable status, the first SMF continues to detect the status of the associated UPFs to determine whether the associated UPFs have recovered from the failure. After the first SMF detects that at least one associated UPF has recovered from the failure, the recovered associated UPF can process session request messages, and then the first SMF sends an update message indicating that the first SMF is in an available status to the NRF. The NRF forwards this update message to the AMF. Correspondingly, after receiving this update message, if the AMF determines that the first SMF is in an available status, it updates the first SMF status recorded locally to an available status.

[0220] For example, the update message carries a second preset identifier indicating that the first SMF is in an available status. The AMF records the second preset identifier corresponding to the first SMF locally.

[0221] Method 4:

[0222] In some embodiments, the method may further include the following steps: if a response message sent by the first SMF is not received within a first set duration after a request message is sent to the first SMF, updating the first SMF status recorded locally to an unavailable status. Wherein, the request message includes a heartbeat detection request message and / or a session request message.

[0223] In one implementation, when the AMF reaches the moment corresponding to the detection period, it sends a heartbeat detection request message to the first SMF. In the case where it is detected that all associated UPFs have failed, the first SMF does not respond to the AMF's heartbeat detection request message. Also, the AMF forwards the session request message to the first SMF after receiving the session request message. Similarly, in the case where it is detected that all associated UPFs have failed, the first SMF does not respond to the AMF's session request message. Correspondingly, if a response message sent by the first SMF is not received within the first set duration after sending a request message to the first SMF, indicating that the first SMF is in an unavailable state, the AMF updates the state of the first SMF recorded locally to the unavailable state.

[0224] Method Five:

[0225] In some embodiments, the method may further include the following steps: If a response message sent by the first SMF is received within the first set duration after sending a request message to the first SMF, update the state of the first SMF recorded locally to the available state.

[0226] In one implementation, when the AMF reaches the moment corresponding to the detection period, it sends a heartbeat detection request message to the first SMF. In the case where it is detected that at least one associated UPF's fault has been recovered, the first SMF returns a heartbeat detection response message to the AMF. Also, the AMF forwards the session request message to the first SMF after receiving the session request message. Similarly, in the case where it is detected that at least one associated UPF's fault has been recovered, the first SMF returns a session response message to the AMF. Correspondingly, if a response message sent by the first SMF is received within the first set duration after sending a request message to the first SMF, indicating that the first SMF is in an available state, update the state of the first SMF recorded locally to the available state.

[0227] Method Six:

[0228] In a possible embodiment, the method may further include the following steps: If a message sent by the first SMF for tearing down the communication link is received, update the state of the first SMF recorded locally to the unavailable state.

[0229] In the case where it is detected that all associated UPFs have failed, the first SMF sends a message for tearing down the communication link to the AMF. Correspondingly, after the AMF receives this message, it determines that the first SMF is in an unavailable state, then updates the state of the first SMF recorded locally to the unavailable state, and determines to disconnect the communication link with the first SMF.

[0230] Method Seven:

[0231] In some embodiments, the method may further include the following steps: if a message for establishing a communication link sent by the first SMF is received, update the status of the first SMF recorded locally to the available status.

[0232] In one implementation, when it is detected that at least one associated UPF has recovered from a fault, the first SMF sends a message for establishing a communication link to the AMF. Correspondingly, after receiving the message, the AMF determines that the first SMF is in the available status, then updates the status of the first SMF recorded locally to the available status, and determines to establish a communication link with the first SMF.

[0233] Mode Eight:

[0234] In a possible embodiment, based on Figure 5 refer to Figure 6 , step S501 may include the following steps:

[0235] S5011: Receive a session response message carrying an error code sent by the first SMF.

[0236] Correspondingly, step S502 may include the following steps:

[0237] S5021: Count the number of session response messages carrying an error code received within a second set duration.

[0238] S5022: When the counted number is greater than the first number, update the status of the first SMF recorded locally to the unavailable status.

[0239] After receiving a session request message sent by the UE, if the AMF determines that the first SMF is the SMF for establishing a session with the UE, the AMF forwards the session request message to the first SMF. If a session response message carrying an error code sent by the first SMF is received, it indicates that the first SMF cannot process the session request message. The AMF counts the number of session response messages carrying an error code received within a second set duration. If the counted number is greater than the first number, it indicates that the unavailability of the first SMF causes the first SMF to be unable to process the session request message, and the AMF updates the status of the first SMF recorded locally to the unavailable status.

[0240] In a possible embodiment, after updating the status of the first SMF to the unavailable status, after reaching a third set duration, the first SMF may recover to the available status. To ensure that a session can be established between the UE and the SMF subsequently, the AMF updates the status of the first SMF recorded locally to the available status.

[0241] In a possible embodiment, the AMF may process a session request message sent by the UE for establishing a new session in the following manner.

[0242] In one implementation, after the AMF receives the session request message sent by the UE, if the session request message carries an activation message for a new session, it indicates that the session request message is used to request the establishment of a new session. For example, the session request message is a PDU Session (Protocol Data Unit Session) message carrying an activation message.

[0243] The AMF locally records the correspondence between each SMF and network configuration information. In this correspondence, the AMF determines the SMF corresponding to the network configuration information carried in the received session request message (in this embodiment, the first SMF is taken as an example for illustration).

[0244] If the AMF determines that the first SMF is in an unavailable state according to the states of each SMF recorded locally, it indicates that the first SMF cannot process the session request message. To reduce the processing pressure of the AMF, when the first preset identifier indicating that the first SMF is in an unavailable state is Undiscoverable, the AMF forwards the session request message to the first SMF. After receiving the session request message, since the associated UPF fails and the first SMF cannot establish a session with the UE, the first SMF sends a session response message indicating that the session establishment fails to the AMF, and the AMF forwards the session response message indicating that the session establishment fails to the UE. Alternatively, to reduce the processing pressure of the first SMF, when the first preset identifier indicating that the first SMF is in an unavailable state is Suspend, the AMF directly sends a session response message indicating that the session establishment fails to the UE.

[0245] In a possible embodiment, the AMF can process the session request message sent by the UE for an established session in the following manner.

[0246] In one implementation, if the AMF receives a session request message for an established session, for example, the session request message is a Service Request message. The AMF locally records the correspondence between each SMF and network configuration information. In this correspondence, the AMF determines the SMF corresponding to the network configuration information carried in the session request message (in this embodiment, the first SMF is taken as an example for illustration).

[0247] After the AMF receives the session request message sent by the UE, since the session request message is for an established session, the AMF does not need to determine a new SMF and directly queries the state of the first SMF in the states of each SMF recorded locally. If the first SMF is in an unavailable state, the AMF can directly send a session response message indicating that the session response fails to the UE. For example, a ServiceReject message.

[0248] After the AMF receives the session request message sent by the UE, since the session request message is for an established session, the AMF directly forwards the session request message to the first SMF. After the first SMF receives the session request message, in the case of a failure of the associated UPF, the first SMF sends a session response message indicating session response failure to the AMF. The AMF forwards the session response message indicating session response failure to the UE.

[0249] In a possible embodiment, after the UE receives the session response message sent by the AMF indicating session establishment failure (or session response failure), the UE may resend the session request message to the AMF, and the AMF may re-determine the available-status SMF for establishing a session with the UE according to the status of each SMF recorded locally, so that the UE can establish a session with the UPF through the determined SMF.

[0250] See Figure 7 , Figure 7 is a flowchart of a fault tolerance method for UPF failure in a communication system provided by an embodiment of the present invention. This method is applied to a communication system. The communication system includes: a UE, a base station, an AMF, an NRF, and two network deployments. The two network deployments are namely site 1 and site 2. Among them, site 1 includes SMF1, SMF2, UPF1, and UPF2. Site 2 includes SMFx and UPFx. This method may include the following steps:

[0251] S701: SMF registration.

[0252] In this step, after the network deployment is completed, the SMF (SMF1 and SMF2) sends a registration request message to the NRF, and the network configuration information corresponding to the SMF is carried in the registration request message. The NRF records the correspondence between the SMF and the network configuration information locally.

[0253] S702: The UE registers to the core network.

[0254] In this step, the UE sends a session request message for creating a new PDU session to the AMF. The AMF determines the corresponding available-status SMF and forwards the session request message to the SMF, and establishes a session between the UE and the UPF docked with it through the SMF, completing the process of the UE registering to the core network.

[0255] S703: The SMF perceives UPF failure through PFCP heartbeat.

[0256] In this step, SMF1 and SMF2 can detect whether UPF1 and UPF2 have failed in the same PFCP heartbeat sensing manner. For example, SMF1 sends a heartbeat detection request message, which is a PFCP message, to all connected UPFs (i.e., UPF1 and UPF2). If SMF1 does not receive a heartbeat response message corresponding to the heartbeat detection request message from the UPF, it determines that the UPF has failed.

[0257] S704: SMF notifies the NRF to modify the status to unavailable.

[0258] In this step, after SMF1 determines that all connected UPFs have failed, it sends an update message indicating that SMF1 is in an unavailable state to the NRF, notifying the NRF to update the locally recorded status of SMF1 to unavailable. Similarly, after the NRF receives an update message indicating that SMF2 is in an unavailable state sent by SMF2, it updates the locally recorded status of SMF2 to unavailable.

[0259] S705: The NRF notifies the AMF that the status of the SMF has changed.

[0260] In this step, the NRF sends an update message indicating that SMF1 is in an unavailable state to the AMF subscribed to SMF1, notifying the AMF that the status of SMF1 has changed. After receiving the update message indicating that SMF1 is in an unavailable state, the AMF updates the locally recorded status of SMF1 to unavailable. Similarly, after the AMF receives an update message indicating that SMF2 is in an unavailable state, it updates the locally recorded status of SMF2 to unavailable.

[0261] S706: The UE initiates a PDU session request message.

[0262] In this step, when the UE needs to access the core network, the UE sends a PDU session request message for creating a new PDU session to the AMF through the base station. For example, a PDU Session Establishment Req (PDU session establishment request) message.

[0263] S707: The AMF selects an available SMF.

[0264] In this step, after receiving the session request message for establishing a new PDU session sent by the UE, the AMF selects an SMF in an available state based on the network configuration information carried in the session request message and the locally recorded status of each SMF. Since SMF1 and SMF2 in location 1 are in an unavailable state, the AMF selects the available SMFx in location 2.

[0265] S708: The AMF forwards the PDU session request message to the selected SMF, and the activation process is completed between the UE and the UPF docked thereto through the SMF.

[0266] In this step, the AMF forwards the PDU session request message to the selected SMFx. After receiving the session request message, the SMFx forwards the session request message to the corresponding UPFx, and a session is established among the UE, SMFx, and UPFx to complete the session activation process initiated by the UE.

[0267] S709: Other service processes.

[0268] In this step, after a session is successfully established among the UE, SMFx, and UPFx, the UE can perform other service processes between the SMFx and UPFx.

[0269] S710: The UE initiates a PDU session request message.

[0270] In this step, if a session has been successfully established among the UE, SMF, and UPF, the UE initiates a PDU session request message for other services to the AMF, that is, the UE initiates an old PDU session for an old user. For example, a Service Request message.

[0271] S711: The AMF forwards the PDU session request message to the SMF requested by the UE.

[0272] In this step, after receiving the PDU session request message for other services, the AMF forwards the PDU session request message to the SMF requested by the UE (for example, SMF1). After receiving the PDU session request message, since the connected UPFs (UPF1 and UPF2) fail, the SMF1 sends a session response message indicating session response failure to the AMF. The AMF forwards the received session response message indicating session response failure to the UE.

[0273] S712: The UE re-initiates a PDU session request message and selects a new SMF.

[0274] In this step, after receiving the session response message indicating session response failure, the UE re-initiates a new PDU session request message to the AMF. Correspondingly, the AMF selects a new available SMF (for example, SMFx) based on the received PDU session request message and establishes a session between the UE and the UPF docked thereto through the SMFx.

[0275] Based on the fault tolerance method for UPF faults in the communication system provided by the embodiments of the present invention, the PFCP heartbeat mechanism of the UPF is detected by the SMF to sense whether the UPF has a fault. When all UPFs have faults, the SMF is in an unavailable state. The SMF notifies the surrounding network elements such as the AMF that the SMF is in an unavailable state by refreshing the status recorded in the NRF, so as to automatically adjust the possibility of the AMF selecting the SMF, which can enhance the automation of network disaster tolerance. Moreover, it can reduce the failure of user PDU session activation caused by UPF faults or the signaling delay caused by reselecting the SMF, and improve the user experience.

[0276] See Figure 8 , Figure 8 FIG. is a flowchart of a fault tolerance method for UPF faults in a communication system provided by an embodiment of the present invention. This method is applied to a communication system. The communication system includes: UE, base station, AMF, NRF, and two network deployments. The two network deployments are namely site 1 and site 2. Among them, site 1 includes SMF1, SMF2, UPF1, and UPF2. Site 2 includes SMFx and UPFx. This method may include the following steps:

[0277] S801: SMF registration.

[0278] In this step, after the network deployment is completed, the SMF (SMF1 and SMF2) sends a registration request message to the NRF, and the network configuration information corresponding to the SMF is carried in the registration request message. The NRF locally records the correspondence between the SMF and the network configuration information.

[0279] S802: UE registers to the core network.

[0280] In this step, the UE sends a session request message for creating a new PDU session to the AMF. The AMF determines the corresponding available SMF and forwards the session request message to the SMF, and a session is established between the UE and the UPF docked with it through the SMF to complete the process of the UE registering to the core network.

[0281] S803: The SMF senses UPF faults through PFCP heartbeat.

[0282] In this step, SMF1 and SMF2 can detect whether UPF1 and UPF2 have faults according to the same PFCP heartbeat sensing method. For example, SMF1 sends a heartbeat detection request message, which is a PFCP message, to all UPFs (i.e., UPF1 and UPF2) it is connected to. SMF1 determines that the UPF has a fault when the UPF does not return a heartbeat response message corresponding to the heartbeat detection request message.

[0283] S804: The SMF actively terminates the HTTP link with the AMF and rejects the new connection request message from the AMF.

[0284] In this step, after SMF1 determines that all the connected UPFs (i.e., UPF1 and UPF2) have failed, SMF1 disconnects the HTTP link with the AMF. For example, SMF1 sends a message to the AMF for terminating the communication link. After SMF2 determines that all the connected UPFs (i.e., UPF1 and UPF2) have failed, SMF2 disconnects the HTTP link with the AMF. For example, SMF2 sends a message to the AMF for terminating the communication link.

[0285] S805: The AMF refreshes the link status of the local SMF.

[0286] In this step, after the AMF detects that the HTTP link with SMF1 is disconnected, for example, receives the message sent by SMF1 for terminating the communication link, it updates the status of SMF1 to the unavailable state. After the AMF detects that the HTTP link with SMF2 is disconnected, it updates the status of SMF2 to the unavailable state.

[0287] S806: The UE initiates a PDU session request message.

[0288] In this step, when the UE needs to access the core network, the UE sends a PDU session request message for creating a new PDU session to the AMF through the base station. For example, the PDU Session Establishment Req message.

[0289] S807: The AMF selects an available SMF.

[0290] In this step, after the AMF receives the session request message sent by the UE for establishing a new PDU session, it selects an SMF in the available state based on the network configuration information carried in the session request message and the status of each SMF recorded locally. Since SMF1 and SMF2 in location 1 are in the unavailable state, the AMF selects SMFx in the available state in location 2.

[0291] S808: The AMF forwards the PDU session request message to the selected SMF, and the SMF completes the activation process between the UE and the UPF it is docked with.

[0292] In this step, the AMF forwards the PDU session request message to the selected SMFx. After receiving the session request message, SMFx forwards the session request message to the corresponding UPFx, and a session is established among the UE, SMFx, and UPFx to complete the session activation process initiated by the UE.

[0293] S809: Other business processes.

[0294] In this step, after the session is successfully established between the UE, SMFx, and UPFx, the UE can perform other business processes between the SMFx and UPFx.

[0295] S810: The UE initiates a PDU session request message.

[0296] In this step, if the session has been successfully established between the UE, SMF, and UPF, the UE sends a PDU session request message for other services to the AMF, that is, the PDU session initiated by the UE is an old PDU session of an old user. For example, a Service Request message.

[0297] S811: The AMF sends a PDU session rejection message to the UE.

[0298] In this step, after receiving the PDU session request message for other services, since the link between the AMF and the SMF (e.g., SMF1) requested by the UE is disconnected, the AMF cannot forward the PDU session request message to SMF1. The AMF sends a session response message indicating session response failure to the UE. For example, a Service Reject message.

[0299] S812: The UE re-initiates a PDU session request message and selects a new SMF.

[0300] In this step, after receiving the session response message indicating session response failure, the UE re-sends a new PDU session request message to the AMF. Correspondingly, the AMF selects a new available SMF (e.g., SMFx) based on the received PDU session request message and establishes a session between the UE and the UPF docked with it through SMFx.

[0301] Based on the method for fault tolerance of UPF failures in the communication system provided by the embodiments of the present invention, the PFCP heartbeat mechanism of the UPF is detected by the SMF, and the UPF failure is sensed. If all UPFs fail, the SMF is in an unavailable state. Through the HTTP mechanism, the heartbeat with the AMF is actively disconnected or the link mechanism with the AMF is removed, so as to automatically adjust the AMF to select the SMF. And it can reduce the failure of user PDU session activation caused by UPF failures or the signaling delay caused by reselecting the SMF, and improve the user experience.

[0302] See Figure 9 , Figure 9The following is a flowchart of a fault tolerance method for UPF failures in a communication system provided by an embodiment of the present invention. This method is applied to a communication system. The communication system includes: a UE, a base station, an AMF, an NRF, and two network deployments. The two network deployments are Site 1 and Site 2. Among them, Site 1 includes SMF1, SMF2, UPF1, and UPF2. Site 2 includes SMFx and UPFx. The method may include the following steps:

[0303] S901: SMF registration.

[0304] In this step, after the network deployment is completed, the SMF (SMF1 and SMF2) sends a registration request message to the NRF. The registration request message carries the network configuration information corresponding to the SMF. The NRF records the correspondence between the SMF and the network configuration information locally.

[0305] S902: The UE registers to the core network.

[0306] In this step, the UE sends a session request message for creating a new PDU session to the AMF. The AMF determines the corresponding available SMF and forwards the session request message to the SMF. A session is established between the UE and the UPF it is docked with through the SMF, completing the process of the UE registering to the core network.

[0307] S903: The UE initiates a PDU session request message.

[0308] In this step, when the UE needs to access the core network, the UE sends a PDU session request message for creating a new PDU session to the AMF through the base station. For example, a PDU Session Establishment Req message.

[0309] S904: The AMF selects an available SMF.

[0310] In this step, after receiving the session request message sent by the UE for establishing a new PDU session, the AMF selects an available SMF (such as SMF2) based on the network configuration information carried in the session request message and the status of each SMF recorded locally.

[0311] S905: The AMF forwards the PDU session request message to the selected SMF.

[0312] In this step, the AMF forwards the PDU session request message to the selected SMF2. After receiving the session request message, since the connected UPF (UPF1 and UPF2) fails, SMF2 sends a session response message indicating session establishment failure to the AMF, that is, the session response message carrying the error code in the foregoing embodiment.

[0313] S906: Re-select other available SMFs.

[0314] In this step, after determining that SMF2 is unavailable, the AMF re-selects an SMF (e.g., SMFx) for establishing a session with the UE based on the status of each SMF recorded locally.

[0315] Moreover, the AMF counts the number of session response messages carrying error codes received within the second set duration; when the counted number is greater than the third number, the AMF updates the status of SMF2 recorded locally to the unavailable state.

[0316] S907: The AMF forwards the PDU session request message to the selected SMF, and the activation process is completed between the UE and the UPF docked with it through the SMF.

[0317] In this step, the AMF forwards the PDU session request message to the selected SMFx. After receiving the session request message, SMFx forwards the session request message to the corresponding UPFx, and a session is established among the UE, SMFx, and UPFx to complete the session activation process initiated by the UE.

[0318] S908: Other service processes.

[0319] In this step, after a session is successfully established among the UE, SMFx, and UPFx, the UE can perform other service processes with SMFx and UPFx.

[0320] S909: The UE initiates a PDU session request message.

[0321] In this step, if a session has been successfully established among the UE, SMF, and UPF, the UE initiates a PDU session request message for other services to the AMF, that is, the UE initiates an old PDU session of an old user. For example, a Service Request message.

[0322] S910: The AMF forwards the PDU session request message to the SMF requested by the UE.

[0323] In this step, after receiving the PDU session request message for other services, the AMF forwards the PDU session request message to the SMF requested by the UE (e.g., SMF1). After receiving this PDU session request message, since the connected UPFs (UPF1 and UPF2) fail, SMF1 sends a session response message indicating session response failure to the AMF. The AMF forwards the received session response message indicating session response failure to the UE.

[0324] S911: The AMF sends a PDU session rejection message to the UE.

[0325] In this step, after receiving the session response message indicating session response failure sent by SMF1, the AMF forwards the received session response message indicating session response failure to the UE. For example, a Service Reject message.

[0326] S912: The UE re-initiates a PDU session request message and selects a new SMF.

[0327] In this step, after receiving the session response message indicating session response failure, the UE re-initiates a new PDU session request message to the AMF. Correspondingly, the AMF selects a new available SMF (e.g., SMFx) based on the received PDU session request message, and establishes a session between the UE and the UPF it docks with through SMFx.

[0328] Based on the UPF fault tolerance method in the communication system provided by the embodiments of the present invention, the PFCP heartbeat mechanism of the UPF is detected by the SMF to sense the UPF fault. If all UPFs fail, the AMF is allowed to re-select other SMFs by means of the error code carried in the session response message replied to the AMF. At the same time, the AMF can count the failure messages of the SMF and their error codes within a certain period of time, and update the locally recorded SMF status. And it can reduce the failure of user PDU session activation caused by UPF faults or the signaling delay caused by re-selecting the SMF, and improve the user experience.

[0329] See Figure 10 , Figure 10 which is a flowchart of a UPF fault tolerance method in a communication system provided by the embodiments of the present invention. This method is applied to a communication system. The communication system includes: a UE, a base station, an AMF, an NRF, and two network deployments. The two network deployments are namely site 1 and site 2. Among them, site 1 includes SMF1, SMF2, UPF1, and UPF2. Site 2 includes SMFx and UPFx. This method may include the following steps:

[0330] S1001: SMF registration.

[0331] In this step, after the network deployment is completed, the SMF (SMF1 and SMF2) sends a registration request message to the NRF, and the network configuration information corresponding to the SMF is carried in the registration request message. The NRF records the correspondence between the SMF and the network configuration information locally.

[0332] S1002: The UE registers to the core network.

[0333] In this step, the UE sends a session request message for creating a new PDU session to the AMF. The AMF determines the SMF in the corresponding available state and forwards the session request message to the SMF. The SMF establishes a session between the UE and the UPF it is docked with, completing the process of the UE registering to the core network.

[0334] S1003: The SMF perceives the UPF failure through PFCP heartbeats, and calculates the relative capacity and load based on the failed UPF and all UPFs.

[0335] In this step, SMF1 and SMF2 can detect whether UPF1 and UPF2 have failed in the same PFCP heartbeat perception manner. For example, SMF1 sends a heartbeat detection request message, which is a PFCP message, to all the connected UPFs (i.e., UPF1 and UPF2). When SMF1 does not receive the heartbeat response corresponding to the heartbeat detection request message from the UPF, it determines that the UPF has failed. Then, when SMF1 detects the UPF failure, it calculates the capacity information and load information of SMF1 based on the number of failed UPFs and the number of all UPFs.

[0336] S1004: The SMF notifies the NRF to modify the capacity and load of the SMF.

[0337] In this step, after determining the capacity information and load information, SMF1 sends an update message carrying the capacity information and load information to the NRF to notify the NRF to update the capacity information and load information of SMF1 recorded locally. Similarly, after determining the capacity information and load information, SMF2 sends an update message carrying the capacity information and load information to the NRF to notify the NRF to update the capacity information and load information of SMF2 recorded locally.

[0338] S1005: The NRF notifies the AMF that the state of the SMF has changed.

[0339] In this step, the NRF sends an update message to the AMF that subscribes to SMF1 to notify the AMF that the state of SMF1 has changed. After receiving the update message for SMF1, the AMF updates the capacity information and load information of SMF1 recorded locally. Similarly, after receiving the update message for SMF2, the AMF updates the capacity information and load information of SMF2 recorded locally.

[0340] S1006: The UE initiates a PDU session request message.

[0341] In this step, when the UE needs to access the core network, the UE sends a PDU session request message for creating a new PDU session to the AMF through the base station. For example, a PDU Session Establishment Req message.

[0342] S1007: The AMF selects an available SMF.

[0343] In this step, after receiving the session request message sent by the UE for establishing a new PDU session, the AMF selects an available SMF based on the network configuration information carried in the session request message and the status of each SMF recorded locally. When the capacity information of SMF1 and SMF2 in site 1 is low, the selection of SMF1 and SMF2 is reduced. For example, select SMFx.

[0344] S1008: The AMF forwards the PDU session request message to the selected SMF, and the SMF completes the activation process between the UE and the UPF it is docked with.

[0345] In this step, the AMF forwards the PDU session request message to the selected SMFx. After receiving the session request message, SMFx forwards the session request message to the corresponding UPFx, and a session is established between the UE, SMFx, and UPFx to complete the session activation process initiated by the UE.

[0346] S1009: Other service processes.

[0347] In this step, after a session is successfully established between the UE, SMFx, and UPFx, the UE can perform other service processes with SMFx and UPFx.

[0348] S1010: The UE initiates a PDU session request message.

[0349] In this step, if a session has been successfully established between the UE, SMF, and UPF, the UE sends a PDU session request message for other services to the AMF, that is, the UE initiates an old PDU session of an old user. For example, a Service Request message.

[0350] S1011: The AMF forwards the PDU session request message to the SMF requested by the UE.

[0351] In this step, after receiving a PDU session request message for other services, the AMF forwards the PDU session request message to the SMF requested by the UE (for example, SMF1). After receiving the PDU session request message, since the connected UPFs (UPF1 and UPF2) have failed, SMF1 sends a session response message indicating session response failure to the AMF. The AMF forwards the received session response message indicating session response failure to the UE. After receiving the PDU session request message, if the connected UPF (UPF1 or UPF2) has not failed, SMF1 directly responds to the PDU session request message.

[0352] S1012: The UE re - initiates a PDU session request message and selects a new SMF.

[0353] In this step, after receiving the session response message indicating session response failure, the UE re - initiates a new PDU session request message to the AMF. Correspondingly, the AMF selects a new available SMF (for example, SMFx) based on the received PDU session request message and establishes a session between the UE and the UPF docked with it through SMFx.

[0354] Based on the UPF fault tolerance method in the communication system provided by the embodiments of the present invention, the SMF detects the UPF failure through the PFCP heartbeat mechanism of the UPF. If all or some of the UPFs fail, the SMF refreshes the capacity and load on the NRF after calculation to notify the surrounding network elements of the AMF of the capacity and load of this SMF, so as to automatically adjust the proportion of the AMF to select the SMF, which can enhance the automation of network disaster tolerance. And it can reduce the failure of user PDU session activation caused by UPF failure or the signaling delay caused by re - selecting the SMF, improving the user experience.

[0355] Corresponding to Figure 2 the method embodiment of Figure 11 , Figure 11 FIG. is the structural diagram of a UPF fault tolerance device in a communication system provided by an embodiment of the present invention. The device is applied to the first SMF in the communication system. The device includes:

[0356] A detection module 1101, configured to detect the status of the associated UPF; wherein, the first SMF is associated with at least one UPF, and the communication system includes multiple SMFs;

[0357] An adjustment module 1102, configured to adjust the possibility of the AMF selecting the first SMF based on the status of the associated UPF.

[0358] In a possible embodiment, the communication system further includes: an NRF;

[0359] The adjustment module 1102 is specifically configured to, when detecting that at least one of the associated UPFs fails, determine the status information of the first SMF based on the number of the failed associated UPFs; wherein, the status information includes: the capacity information of the first SMF, and / or, the load information; and send an update message carrying the status information of the first SMF to the NRF.

[0360] In a possible embodiment, the adjustment module 1102 is specifically configured to, when detecting that at least one of the associated UPFs recovers from a failure, determine the status information of the first SMF based on the number of the associated UPFs that have recovered from the failure; and send an update message carrying the status information of the first SMF to the NRF.

[0361] In a possible embodiment, the communication system further includes: an NRF;

[0362] The adjustment module 1102 is specifically configured to, when detecting that all of the associated UPFs have failed, send an update message indicating that the first SMF is in an unavailable state to the NRF.

[0363] In a possible embodiment, the adjustment module 1102 is specifically configured to, when detecting that at least one of the associated UPFs recovers from a failure, send an update message indicating that the first SMF is in an available state to the NRF.

[0364] In a possible embodiment, the update message is a TCP message.

[0365] In a possible embodiment, the adjustment module 1102 is specifically configured to, when detecting that all of the associated UPFs have failed, disconnect the communication link with the AMF.

[0366] In a possible embodiment, the adjustment module 1102 is specifically configured to, when detecting that all of the associated UPFs have failed, send a message for tearing down the communication link to the AMF.

[0367] In a possible embodiment, the adjustment module 1102 is specifically configured to, when detecting that at least one of the associated UPFs recovers from a failure, restore the communication link with the AMF.

[0368] In a possible embodiment, the adjustment module 1102 is specifically configured to, when detecting that at least one of the associated UPFs recovers from a failure, send a message for establishing the communication link to the AMF.

[0369] In a possible embodiment, the adjustment module 1102 is specifically configured to, when it is detected that all the associated UPFs have failed and a session request message sent by the AMF is received, send a session response message carrying an error code to the AMF.

[0370] In a possible embodiment, the detection module 1101 is specifically configured to, at the moment corresponding to the detection period, send a heartbeat detection request message to the associated UPF; for each associated UPF, if a heartbeat detection response message sent by the associated UPF is not received within a first set duration after sending the heartbeat detection request message, determine that the associated UPF has failed; if a heartbeat detection response message sent by the associated UPF is received within a first set duration after sending the heartbeat detection request message, determine that the associated UPF is in a normal state or the fault has been recovered.

[0371] In a possible embodiment, the detection module 1101 is specifically configured to, at the moment corresponding to the detection period, send a heartbeat detection request message to the associated UPF; for each associated UPF, if a heartbeat detection response message sent by the associated UPF is not received after continuously sending heartbeat detection request messages to the associated UPF for multiple detection periods, determine that the associated UPF has failed; if a heartbeat detection response message sent by the associated UPF is received within a first set duration after sending the heartbeat detection request message, determine that the associated UPF is in a normal state or the fault has been recovered.

[0372] Based on the UPF fault tolerance device in the communication system provided by the embodiments of the present invention, the possibility of the AMF automatically selecting the SMF can be realized, and the automaticity of network disaster tolerance can be enhanced.

[0373] Corresponding to the method embodiment of Figure 5 See Figure 12 Figure 12 FIG. is a structural diagram of a UPF fault tolerance device in a communication system provided by an embodiment of the present invention. The device is applied to the AMF in the communication system. The device includes:

[0374] An update message receiving module 1201, configured to receive an update message carrying a first SMF state, where the first SMF state is related to the state of the UPF associated with the first SMF;

[0375] A first state update module 1202, configured to update the locally recorded first SMF state according to the received update message, so as to adjust the possibility of the AMF selecting the first SMF.

[0376] ​In a possible embodiment, the update message receiving module 1201 is specifically configured to receive an update message carrying the status information of the first SMF sent by the NRF; wherein, the status information includes: the capacity information of the first SMF, and / or, the load information;

[0377] The first status update module 1202 is specifically configured to update the status information of the first SMF recorded locally.

[0378] In a possible embodiment, the update message receiving module 1201 is specifically configured to receive an update message sent by the NRF indicating that the first SMF is in an unavailable state;

[0379] The first status update module 1202 is specifically configured to update the status of the first SMF recorded locally to an unavailable state.

[0380] In a possible embodiment, the update message receiving module 1201 is specifically configured to receive an update message sent by the NRF indicating that the first SMF is in an available state;

[0381] The first status update module 1202 is specifically configured to update the status of the first SMF recorded locally to an available state.

[0382] In a possible embodiment, the device further includes:

[0383] A second status update module, configured to update the status of the first SMF recorded locally to an unavailable state if a response message sent by the first SMF is not received within a first set duration after a request message is sent to the first SMF; wherein, the request message includes a heartbeat detection request message, and / or, a session request message.

[0384] In a possible embodiment, the device further includes:

[0385] A third status update module, configured to update the status of the first SMF recorded locally to an available state if a response message sent by the first SMF is received within a first set duration after a request message is sent to the first SMF.

[0386] In a possible embodiment, the device further includes:

[0387] A fourth status update module, configured to update the status of the first SMF recorded locally to an unavailable state if a message for tearing down a communication link sent by the first SMF is received.

[0388] In a possible embodiment, the device further includes:

[0389] A fifth status update module, configured to update the status of the first SMF recorded locally to an available status if a message for establishing a communication link sent by the first SMF is received.

[0390] In a possible embodiment, the update message receiving module 1201 is specifically configured to receive a session response message carrying an error code sent by the first SMF;

[0391] The first status update module 1202 is specifically configured to count the number of session response messages carrying an error code received within a second set duration; when the counted number is greater than a first number, update the status of the first SMF recorded locally to an unavailable status.

[0392] In a possible embodiment, the apparatus further includes:

[0393] A sixth status update module, configured to, after the first status update module 1202 executes the operation of updating the status of the first SMF recorded locally to an unavailable status, update the status of the first SMF recorded locally to an available status when a third set duration is reached.

[0394] Based on the fault tolerance apparatus for UPF faults in the communication system provided by the embodiments of the present invention, it is possible to automatically adjust the possibility of the AMF selecting the SMF, and enhance the automation of network disaster tolerance.

[0395] Embodiments of the present invention further provide an electronic device, as Figure 13 shown, including a processor 1301, a communication interface 1302, a memory 1303, and a communication bus 1304, where the processor 1301, the communication interface 1302, and the memory 1303 complete mutual communication through the communication bus 1304;

[0396] The memory 1303 is used for storing a computer program;

[0397] The processor 1301 is configured to, when executing the program stored on the memory 1303, implement the steps of the fault tolerance method for UPF faults in any of the above-mentioned communication systems.

[0398] The communication bus mentioned in the above electronic device may be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. This communication bus can be divided into an address bus, a data bus, a control bus, etc. For the sake of simplicity, only a thick line is shown in the figure, but it does not mean that there is only one bus or one type of bus.

[0399] The communication interface is used for communication between the above-mentioned electronic device and other devices.

[0400] The memory may include a Random Access Memory (RAM), or may also include a non-volatile memory (Non-Volatile Memory, NVM), such as at least one disk memory. Optionally, the memory may also be at least one storage device located away from the aforementioned processor.

[0401] The above-mentioned processor may be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), etc.; it may also be a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

[0402] In another embodiment provided by the present invention, there is also provided a computer-readable storage medium, in which a computer program is stored, and when the computer program is executed by a processor, the steps of the fault tolerance method for UPF faults in any of the above-mentioned communication systems are implemented.

[0403] In another embodiment provided by the present invention, there is also provided a computer program product containing instructions, which when running on a computer, causes the computer to execute the fault tolerance method for UPF faults in any of the above-mentioned communication systems in the embodiments.

[0404] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions described in the embodiments of the present invention are generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from a website, computer, server, or data center to another website, computer, server, or data center via wired (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.) means. The computer-readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. that includes one or more integrated available media. The available media may be magnetic media (such as floppy disks, hard disks, magnetic tapes), optical media (such as DVDs), or semiconductor media (such as solid state disks (SSDs)).

[0405] It should be noted that in this document, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variation thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of additional identical elements in the process, method, article or device including the element.

[0406] Each embodiment in this specification is described in a related manner. The same or similar parts among the embodiments can be referred to each other, and the differences between each embodiment and other embodiments are emphasized. In particular, for the embodiments of the apparatus, electronic device, computer-readable storage medium, and computer program product, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts can be referred to the description of the method embodiments.

[0407] The above are only the preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention are all included within the protection scope of the present invention.

Claims

1. A fault tolerance method for the user plane function UPF failure in a communication system, characterized in that The method is applied to a first Session Management Function (SMF) in the communication system, and the method includes: Detecting the status of an associated User Plane Function (UPF); wherein, the first SMF is associated with at least one UPF, and the communication system includes multiple SMFs; Adjusting the possibility that an Access and Mobility Management Function (AMF) selects the first SMF based on the status of the associated UPF.

2. The method according to claim 1, wherein The communication system further includes: a Network Repository Function (NRF); The adjusting the possibility that the AMF selects the first SMF based on the status of the associated UPF includes: In the case of detecting that at least one of the associated UPFs fails, determining status information of the first SMF based on the number of the failed associated UPFs; wherein, the status information includes: capacity information of the first SMF, and / or, load information; Sending an update message carrying the status information of the first SMF to the NRF.

3. The method according to claim 2, wherein The adjusting the possibility that the AMF selects the first SMF based on the status of the associated UPF includes: In the case of detecting that at least one of the associated UPFs recovers from a failure, determining status information of the first SMF based on the number of the associated UPFs that recover from the failure; Sending an update message carrying the status information of the first SMF to the NRF.

4. The method according to claim 1, characterized in that, The communication system further includes: NRF; The adjusting the possibility that the AMF selects the first SMF based on the status of the associated UPF includes: In the case of detecting that all of the associated UPFs fail, sending an update message indicating that the first SMF is in an unavailable state to the NRF.

5. The method according to claim 4, wherein The adjusting the possibility that the AMF selects the first SMF based on the status of the associated UPF includes: In the case of detecting that at least one of the associated UPFs recovers from a failure, sending an update message indicating that the first SMF is in an available state to the NRF.

6. The method according to any one of claims 2 to 5, characterized in that The update message is a TCP message.

7. The method according to claim 1, wherein The adjusting the possibility that the AMF selects the first SMF based on the status of the associated UPF includes: In the case of detecting that all of the associated UPFs fail, disconnecting the communication link with the AMF.

8. The method according to claim 7, wherein The disconnecting the communication link with the AMF in the case of detecting that all of the associated UPFs fail includes: In the case of detecting that all of the associated UPFs fail, sending a message for tearing down the communication link to the AMF.

9. The method according to claim 7, wherein The adjusting the possibility that the AMF selects the first SMF based on the status of the associated UPF includes: In the case of detecting that at least one of the associated UPFs recovers from a failure, restoring the communication link with the AMF.

10. The method according to claim 9, characterized in that, The restoring the communication link with the AMF in the case of detecting that at least one of the associated UPFs recovers from a failure includes: In the case of detecting that at least one of the associated UPFs recovers from a failure, sending a message for establishing the communication link to the AMF.

11. The method according to claim 1, characterized in that, The adjusting the possibility that the AMF selects the first SMF based on the status of the associated UPF includes: In the case where it is detected that each of the associated UPFs has failed, if a session request message sent by the AMF is received, a session response message carrying an error code is sent to the AMF.

12. The method according to claim 1, characterized in that, The detecting the status of the associated UPF includes: At the moment corresponding to the detection period, a heartbeat detection request message is sent to the associated UPF; For each associated UPF, if a heartbeat detection response message sent by the associated UPF is not received within a first set duration after the heartbeat detection request message is sent, it is determined that the associated UPF has failed; If a heartbeat detection response message sent by the associated UPF is received within a first set duration after the heartbeat detection request message is sent, it is determined that the associated UPF is in a normal state or the failure has been recovered.

13. The method according to claim 1, wherein The detecting the status of the associated UPF includes: At the moment corresponding to the detection period, a heartbeat detection request message is sent to the associated UPF; For each associated UPF, if a heartbeat detection response message sent by the associated UPF is not received after sending the heartbeat detection request message for a continuous plurality of detection periods, it is determined that the associated UPF has failed; If a heartbeat detection response message sent by the associated UPF is received within a first set duration after the heartbeat detection request message is sent, it is determined that the associated UPF is in a normal state or the failure has been recovered.

14. A fault tolerance method for UPF faults in a communication system, characterized in that, The method is applied to the AMF in the communication system, and the method includes: Receiving an update message carrying a first SMF state, where the first SMF state is related to the state of the UPF associated with the first SMF; According to the received update message, updating the first SMF state recorded locally to adjust the possibility of the AMF selecting the first SMF.

15. The method according to claim 14, characterized in that The receiving an update message carrying a first SMF state includes: Receiving an update message sent by the NRF and carrying the state information of the first SMF; where the state information includes: the capacity information of the first SMF, and / or, the load information; The updating the first SMF state recorded locally according to the received update message includes: Updating the state information of the first SMF recorded locally.

16. The method according to claim 14, wherein The receiving an update message carrying a first SMF state includes: Receiving an update message sent by the NRF indicating that the first SMF is in an unavailable state; The updating the first SMF state recorded locally according to the received update message includes: Updating the first SMF state recorded locally to an unavailable state.

17. The method according to claim 16, characterized in that, The receiving an update message carrying a first SMF state includes: Receiving an update message sent by the NRF indicating that the first SMF is in an available state; The updating the first SMF state recorded locally according to the received update message includes: Updating the first SMF state recorded locally to an available state.

18. The method according to claim 14, wherein, The method further includes: If a response message sent by the first SMF is not received within a first set duration after sending a request message to the first SMF, update the status of the first SMF recorded locally to an unavailable status; wherein, the request message includes a heartbeat detection request message, and / or, a session request message.

19. The method according to claim 18, wherein The method further includes: If a response message sent by the first SMF is received within a first set duration after sending a request message to the first SMF, update the status of the first SMF recorded locally to an available status.

20. The method according to claim 14, wherein The method further includes: If a message for tearing down a communication link sent by the first SMF is received, update the status of the first SMF recorded locally to an unavailable status.

21. The method according to claim 20, wherein The method further includes: If a message for establishing a communication link sent by the first SMF is received, update the status of the first SMF recorded locally to an available status.

22. The method according to claim 14, wherein The receiving an update message carrying the status of the first SMF includes: Receiving a session response message carrying an error code sent by the first SMF; The updating the status of the first SMF recorded locally according to the received update message includes: Counting the number of session response messages carrying an error code received within a second set duration; When the counted number is greater than a first number, update the status of the first SMF recorded locally to an unavailable status.

23. The method according to claim 22, wherein After updating the status of the first SMF recorded locally to an unavailable status, the method further includes: When a third set duration is reached, update the status of the first SMF recorded locally to an available status.

24. A fault tolerance device for UPF faults in a communication system, characterized in that, The apparatus is applied to the first SMF in the communication system, and the apparatus includes: A detection module, configured to detect the status of an associated UPF; wherein, the first SMF is associated with at least one UPF, and the communication system includes multiple SMFs; An adjustment module, configured to adjust the possibility that the AMF selects the first SMF based on the status of the associated UPF.

25. A fault tolerance device for UPF faults in a communication system, characterized in that, The apparatus is applied to the AMF in the communication system, and the apparatus includes: An update message receiving module, configured to receive an update message carrying the status of the first SMF, where the status of the first SMF is related to the status of the UPF associated with the first SMF; A first status update module, configured to update the status of the first SMF recorded locally according to the received update message, so as to adjust the possibility that the AMF selects the first SMF.

26. An electronic device, characterized in that, It includes a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory complete mutual communication through the communication bus; The memory is used for storing a computer program; The processor is configured to implement the method steps of any one of claims 1-13, or claims 14-23 when executing the program stored on the memory.

27. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, and when the computer program is executed by the processor, it implements the method of any one of claims 1-13, or claims 14-23.

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