Session establishment method and device

Abstract

This specification provides a session establishment method and device. The method includes: sending, by an SMF entity, a PDU session establishment request message to a terminal, where the PDU session establishment request message is used to request to establish a PDU session; and receiving, by the SMF entity, a PDU session establishment response message from the terminal. A method for actively initiating a PDU session establishment procedure on a network side is provided.

What is claimed is: 
     
         1 . A session establishment method, comprising:
 sending, by a session management function (SMF) entity, a packet data unit (PDU) session establishment request message to a terminal, wherein the PDU session establishment request message is used to request to establish a PDU session; and   receiving, by the SMF entity, a PDU session establishment response message from the terminal.   
     
     
         2 . The method according to  claim 1 , wherein the PDU session establishment response message comprises a session identifier of the PDU session, or
 the method further comprises: receiving, by the SMF entity, a session identifier of the PDU session from the terminal.   
     
     
         3 . The method according to  claim 1 , wherein the PDU session establishment request message comprises session establishment assistance information of the PDU session; or
 the method further comprises: sending, by the SMF entity, session establishment assistance information of the PDU session to the terminal, wherein   the session establishment assistance information of the PDU session comprises one or more of a broadcast session identifier and a group identifier, the broadcast session identifier is used to represent a broadcast session in which the terminal participates, and the group identifier is used to represent a group comprising the terminal.   
     
     
         4 . The method according to  claim 3 , wherein the method further comprises: selecting, by the SMF entity based on the broadcast session identifier, a user plane function (UPF) entity corresponding to the broadcast session, and sending a user plane session request to the UPF entity corresponding to the broadcast session; or
 selecting, by the SMF entity based on the group identifier, a UPF entity corresponding to the group identifier, and sending a user plane session request to the UPF entity corresponding to the group identifier, wherein   the user plane session request comprises user plane forwarding rule information of the PDU session.   
     
     
         5 . A session establishment method, comprising:
 receiving, by a terminal, a packet data unit (PDU) session establishment request message from a session management function (SMF) entity, wherein the PDU session establishment request message is used to request to establish a PDU session; and   sending, by the terminal, a PDU session establishment response message to the SMF entity based on the PDU session establishment request message.   
     
     
         6 . The method according to  claim 5 , wherein the PDU session establishment response message comprises a session identifier of the PDU session; or
 the method further comprises: sending, by the terminal, a session identifier of the PDU session to the SMF entity.   
     
     
         7 . The method according to  claim 5 , wherein the PDU session establishment request message comprises session establishment assistance information of the PDU session, and the method further comprises: obtaining, by the terminal based on the session establishment assistance information of the PDU session, information about a quality of service flow (QoS) flow corresponding to the PDU session; or
 the method further comprises: receiving, by the terminal, session establishment assistance information of the PDU session from the SMF entity, and obtaining, based on the session establishment assistance information of the PDU session, information about a QoS flow corresponding to the PDU session, wherein   the session establishment assistance information of the PDU session comprises one or more of a broadcast session identifier and a group identifier, the broadcast session identifier is used to represent a broadcast session in which the terminal participates, and the group identifier is used to represent a group comprising the terminal.   
     
     
         8 . The method according to  claim 5 , wherein the PDU session establishment request message comprises the session identifier of the PDU session. 
     
     
         9 . An apparatus comprising:
 a non-transitory memory storage comprising instructions; and   one or more processors in communication with the memory storage, wherein the one or more processors execute the instructions to:   send a packet data unit (PDU) session establishment request message to a terminal, wherein the PDU session establishment request message is used to request to establish a PDU session; and   receive a PDU session establishment response message from the terminal.   
     
     
         10 . The apparatus according to  claim 9 , wherein the PDU session establishment response message comprises a session identifier of the PDU session, or
 the one or more processors are further configured to: receive a session identifier of the PDU session from the terminal.   
     
     
         11 . The apparatus according to  claim 9 , wherein the PDU session establishment request message comprises session establishment assistance information of the PDU session; or
 the one or more processors are further configured to: send session establishment assistance information of the PDU session to the terminal, wherein   the session establishment assistance information of the PDU session comprises one or more of a broadcast session identifier and a group identifier, the broadcast session identifier is used to represent a broadcast session in which the terminal participates, and the group identifier is used to represent a group comprising the terminal.   
     
     
         12 . The apparatus according to  claim 11 , wherein the one or more processors are further configured to: select, based on the broadcast session identifier, a user plane function (UPF) entity corresponding to the broadcast session, and send a user plane session request to the UPF entity corresponding to the broadcast session; or
 select, based on the group identifier, a UPF entity corresponding to the group identifier, and send a user plane session request to the UPF entity corresponding to the group identifier, wherein   the user plane session request comprises user plane forwarding rule information of the PDU session.   
     
     
         13 . An apparatus comprising:
 a non-transitory memory storage comprising instructions; and   one or more processors in communication with the memory storage, wherein the one or more processors execute the instructions to:   receive a packet data unit (PDU) session establishment request message from a session management function (SMF) entity, wherein the PDU session establishment request message is used to request to establish a PDU session; and   send a PDU session establishment response message to the SMF entity based on the PDU session establishment request message.   
     
     
         14 . The apparatus according to  claim 13 , wherein the PDU session establishment response message comprises a session identifier of the PDU session; or
 the one or more processors are further configured to: send a session identifier of the PDU session to the SMF entity.   
     
     
         15 . The apparatus according to  claim 13 , wherein the PDU session establishment request message comprises session establishment assistance information of the PDU session, and the one or more processors are further configured to: obtain, based on the session establishment assistance information of the PDU session, information about a quality of service flow (QoS) flow corresponding to the PDU session; or
 the one or more processors are further configured to: receive session establishment assistance information of the PDU session from the SMF entity, and obtain, based on the session establishment assistance information of the PDU session, information about a QoS flow corresponding to the PDU session, wherein   the session establishment assistance information of the PDU session comprises one or more of a broadcast session identifier and a group identifier, the broadcast session identifier is used to represent a broadcast session in which a terminal participates, and the group identifier is used to represent a group comprising the terminal.   
     
     
         16 . The apparatus according to  claim 13 , wherein the PDU session establishment request message comprises the session identifier of the PDU session.