Method for implementing service continuity and related device

An apparatus, comprising:

• at least one memory configured to store computer program code;
• and
• at least one processor configured to access said computer program code and operate as instructed by said computer program code, said computer program code comprising:
• first receiving code configured to cause the at least one processor to receive a target relocation message, the target relocation message carrying target traffic routing information, the target traffic routing information comprising a target data network (DN) access identifier (DNAI) and network address translation (NAT) information, the NAT information comprising a target user equipment (UE) network address, a first application server (AS) network address, and a second AS network address, wherein a target UE corresponding to the target UE network address has established a target protocol data unit (PDU) session to a first PDU session anchor (PSA) user plane function (UPF) network element and is configured to communicate with a first AS corresponding to the first AS network address;
• first generating code configured to cause the at least one processor to generate a packet processing rule based on the target traffic routing information, the packet processing rule comprising an NAT rule, the NAT rule comprising:
• translating a target address of an uplink packet transmitted by the target UE from the first AS network address into the second AS network address, and
• translating a source address of a received downlink packet whose target address is the target UE network address from the second AS network address into the first AS network address;
• and
• first delivering code configured to cause the at least one processor to deliver the packet processing rule to a target network device, to cause the target network device to forward, based on the packet processing rule, the uplink packet transmitted by the target UE to a second AS corresponding to the second AS network address and the received downlink packet whose target address is the target UE network address and whose source address is the second AS network address to the target UE.

A non-transitory computer-readable storage medium storing computer instructions that, when executed by at least one processor, cause the at least one processor to:

• receive a target relocation message, the target relocation message carrying target traffic routing information, the target traffic routing information comprising a target data network (DN) access identifier (DNAI) and network address translation (NAT) information, the NAT information comprising a target user equipment (UE) network address, a first application server (AS) network address, and a second AS network address, wherein a target UE corresponding to the target UE network address has established a target protocol data unit (PDU) session to a first PDU session anchor (PSA) user plane function (UPF) network element and is configured to communicate with a first AS corresponding to the first AS network address;
• generate a packet processing rule based on the target traffic routing information, the packet processing rule comprising an NAT rule, the NAT rule comprising:
• translating a target address of an uplink packet transmitted by the target UE from the first AS network address into the second AS network address, and
• translating a source address of a received downlink packet whose target address is the target UE network address from the second AS network address into the first AS network address;
• and
• deliver the packet processing rule to a target network device, to cause the target network device to forward, based on the packet processing rule, the uplink packet transmitted by the target UE to a second AS corresponding to the second AS network address and the received downlink packet whose target address is the target UE network address and whose source address is the second AS network address to the target UE.