Service continuity implementation method, device, and service continuity implementation system

A session management function entity, comprising:

• at least one processor;
• and
• a memory storing computer-executable instructions that, when executed by the at least one processor, instruct the at least one processor to:
• select a target user plane function entity to serve a terminal;
• send first path information to the target user plane function entity;
• send second path information to a source user plane function entity, wherein the first path information and the second path information are for establishing a forwarding path between the target user plane function entity and the source user plane function entity;
• send a first message to a control device;
• receive indication information of a first application server (AS) from the control device;
• and
• send a first routing rule to the target user plane function entity based on the indication information of the first AS, wherein the first routing rule specifies that data whose destination address is an address of the first AS is to be sent to the first AS.

A service continuity implementation system, comprising:

• a session management function entity configured to:
• select a target user plane function entity to serve a terminal;
• send first path information to the target user plane function entity;
• send second path information to a source user plane function entity, wherein the first path information and the second path information are used to establish a forwarding path between the target user plane function entity and the source user plane function entity;
• and
• send a first message to a controller;
• and
• the controller, wherein the controller configured to send indication information of a first application server (AS),
• wherein the session management function entity is further configured to:
• receive the indication information of the first AS;
• and
• send a first routing rule to the target user plane function entity based on the indication information of the first AS,
• wherein the first routing rule specifies that data whose destination address is an address of the first AS is to be sent to the first AS.