Method for inserting SMF and AMF entity

1. A method of inserting a Session Management Function (SMF), the method being applied for an Access and Mobility Management Function (AMF) entity and comprising:

in a case that a User Equipment (UE) moves out of a service area of a first SMF entity currently serving a first Packet Data Unit (PDU) session of the UE, or in a case that selecting a SMF entity for the UE is needed, querying, by using information relevant to the UE, a second SMF entity capable of serving the UE; and

updating the first PDU session by using the second SMF entity,

wherein in a case that the UE moves out of the service area of the first SMF entity currently serving the first PDU session of the UE, or in a case that selecting the SMF entity for the UE is needed, querying, by using information relevant to the UE, the second SMF entity capable of serving the UE, comprises:

determining that the UE moves out of the service area of the first SMF entity according to information of the service area of the first SMF entity provided by a Network Repository Function (NRF) entity; and

querying, by using the information relevant to the UE, the second SMF entity capable of serving the UE;

wherein

determining that the UE moves out of the service area of the first SMF entity according to information of the service area of the first SMF entity provided by the NRF entity, comprises:

obtaining and storing the information of the service area of the first SMF entity provided by the NRF entity; and

determining, according to the information of the service area of the first SMF entity during a registration update process, a service request process, or a handover process of the UE, that the UE moves out of the service area of the first SMF entity;

before in a case that the UE moves out of the service area of the first SMF entity currently serving the first PDU session of the UE, or in a case that selecting a SMF entity for the UE is needed, querying, by using information relevant to the UE, the second SMF entity capable of serving the UE, the method further comprises:

receiving a registration request message or a service request message sent by the UE, or a handover request or a path switch request message sent by a base station serving the UE; and

determining information of the first PDU session of the UE, wherein the information of the first PDU session comprises an identifier (ID) of the first SMF entity and information of a network slice to which the first PDU session belongs.

2. The method according to claim 1 , further comprising:

providing location information of the UE to the first SMF entity.

3. The method according to claim 1 , wherein the first SMF entity comprises an anchor SMF entity or a first intermediate SMF entity.

4. The method according to claim 1 , wherein in a case that a registration request message or a service request message sent by the UE is further received, or a handover request or a path switch request message sent by a base station serving the UE is received, the method further comprises:

determining that the second SMF entity is serving the UE in a network; and

judging whether the second SMF entity is still able to serve the UE or not;

wherein, in a case that the second SMF entity is still able to serve the UE, and if an anchor SMF entity of the first PDU session differs from the second SMF entity, then the second SMF entity is inserted into the first PDU session;

in a case that the second SMF entity is unable to continue providing the service, a third SMF entity capable of serving the UE is queried, and the third SMF entity is inserted into the first PDU session.

5. The method according to claim 1 , wherein, in a case that a registration request message or a service request message sent by the UE is further received, or a handover request or a path switch request message sent by a base station serving the UE is received, the method further comprises:

determining, according to information of the network slice to which the first PDU session belongs, that the second SMF entity is serving the UE in the network slice to which the first PDU session belongs; and

judging whether the second SMF entity is still able to serve the UE or not;

wherein, in a case that the second SMF entity is still able to serve the UE, and if an anchor SMF entity of the first PDU session differs from the second SMF entity, then the second SMF entity is inserted into the first PDU session; in a case that the second SMF entity is unable to continue providing the service, a fourth SMF entity capable of serving the UE is queried, and the fourth SMF entity is inserted into the first PDU session.

6. The method according to claim 1 , further comprising:

determining that the second SMF entity is serving the UE in a network; and

in a case that the UE moves out of a service area of a fifth SMF entity currently serving a second PDU session of the UE, or in a case that selecting a SMF entity for the UE is needed, inserting the second SMF entity into the second PDU session.

7. The method according to claim 1 , further comprising:

determining, according to the information of the network slice to which the first PDU session belongs, that a second PDU session of the UE exists in the network slice to which the first PDU session belongs;

determining that the second SMF entity is serving the UE in the network slice to which the first PDU session belongs;

in a case that the UE moves out of a service area of a sixth SMF entity currently serving the second PDU session, or in a case that selecting a SMF entity for the UE is needed, inserting the second SMF entity into the second PDU session.

8. The method according to claim 1 , wherein querying, by using the information relevant to the UE, the second SMF entity capable of serving the UE, comprises:

querying, using the information relevant to the UE, the NRF entity, and obtaining information of the second SMF entity; and

determining the second SMF entity according to the information of the second SMF entity.

9. The method according to claim 8 , wherein the information of the second SMF entity comprises information of a service area of the second SMF entity;

after determining the second SMF entity according to the information of the second SMF entity, the method further comprises:

storing the information of the service area of the second SMF entity, and deleting the information of the service area of the first SMF entity.

10. An Access and Mobility Management Function (AMF) entity, comprising:

a query circuit, configured for, in a case that a User Equipment (UE) moves out of a service area of a first SMF entity currently serving a first Packet Data Unit (PDU) session of the UE, or in a case that selecting a SMF entity for the UE is needed, querying, by using information relevant to the UE, a second SMF entity capable of serving the UE; and

an update circuit, configured for updating the first PDU session by using the second SMF entity,

wherein in a case that the UE moves out of the service area of the first SMF entity currently serving the first PDU session of the UE, or in a case that selecting the SMF entity for the UE is needed, querying, by using information relevant to the UE, the second SMF entity capable of serving the UE, comprises:

determining that the UE moves out of the service area of the first SMF entity according to information of the service area of the first SMF entity provided by a Network Repository Function (NRF) entity; and

querying, by using the information relevant to the UE, the second SMF entity capable of serving the UE;

wherein

determining that the UE moves out of the service area of the first SMF entity according to information of the service area of the first SMF entity provided by the NRF entity, comprises:

obtaining and storing the information of the service area of the first SMF entity provided by the NRF entity; and

determining, according to the information of the service area of the first SMF entity during a registration update process, a service request process, or a handover process of the UE, that the UE moves out of the service area of the first SMF entity,

wherein the AMF entity further comprises:

a receiving circuit, configured to receive a registration request message or a service request message sent by the UE, or receive a handover request or a path switch request message sent by a base station serving the UE; and

a first determining circuit, configured to determine information of the first PDU session of the UE, wherein the information of the first PDU session comprises an identifier (ID) of the first SMF entity and information of a network slice to which the first PDU session belongs.

11. An AMF entity, comprising a processor, a storage and a computer program stored on the storage and executable by the processor, wherein, in a case that the computer program is executed by the processor, the processor implements steps of the method of inserting an SMF according to claim 1 .

12. A non-transitory computer readable storage medium, comprising:

a computer program stored on the non-transitory computer readable storage medium, wherein in a case that the computer program is executed by a computer processor, the computer processor implements steps of the method of inserting an SMF according to claim 1 .