Session management method and apparatus

Abstract

A session management method and an apparatus, where the method includes: obtaining, by a session management function (SMF), a point-to-point protocol over Ethernet (PPPoE) message from a user equipment; assigning a PPPoE session identifier and/or an Internet Protocol (IP) address to the user equipment; and sending, by the SMF, the assigned PPPoE session identifier and/or IP address to the user equipment, to establish a PPPoE connection between the user equipment and a network side device. The method is performed after a packet data unit (PDU) session is successfully established. The SMF sends the PPPoE session identifier and/or the IP address to the user equipment. In this case, the user equipment can store a correspondence between the established PDU session and a PPPoE session, such that the user equipment accesses a 5G core network (CN) through a fixed network.

Claims

1. A session management method, comprising: sending, by a user equipment after establishing a packet data unit (PDU) session, a point-to-point protocol over Ethernet (PPPoE) message to an access gateway function (AGF), wherein the PPPoE message is for use in at least one of a PPPoE discovery process, an internet protocol control protocol (IPCP) process, or a link control protocol (LCP) process, and wherein the PPPoE message is encapsulated using one of a medium access control (MAC) address that is of the AGF and that corresponds to the PDU session or a MAC address that is of a user plane function (UPF) and that corresponds to a PPPoE session; and receiving, by the user equipment, a PPPoE session identifier and/or an Internet Protocol (IP) address to establish a PPPoE connection between the user equipment and a network side device.

2. The session management method according to claim 1, wherein before sending the PPPoE message, the session management method further comprises sending, by the user equipment, a PDU session establishment request message to the AGF, wherein the PDU session establishment request message comprises: the PPPoE message; a manner for instructing the user equipment to obtain the IP address based on a PPPoE procedure; information indicating a fixed network access type; or information indicating a fixed network service.

3. The session management method according to claim 2, wherein the PDU session establishment request message is encapsulated in a non-access stratum (NAS) message, and wherein the NAS message is: encapsulated in a layer 2 data packet and identified using one of a virtual local area network (VLAN) label, a multiprotocol label switching (MPLS) label, the MAC address of the AGF, or an Ethernet type; encapsulated in a layer 3 data packet and identified using a user datagram protocol (UDP) port number or a predetermined destination IP address; encapsulated in the PPPoE session and identified using the PPPoE session identifier; encapsulated in a generic routing encapsulation (GRE) tunnel and identified using a GRE tunnel identifier; encapsulated in an extensible authentication protocol (EAP) message and identified using an EAP parameter; or encapsulated in a predetermined protocol layer and identified using the predetermined protocol layer.

4. The session management method according to claim 3, further comprising receiving, by the user equipment, a PDU session establishment success message, wherein the PDU session establishment success message comprises the MAC address that is of the AGF and that is assigned by the AGF to the PDU session, or wherein the PDU session establishment success message is encapsulated in the MAC address that is of the AGF and that is assigned by the AGF to the PDU session.

5. An apparatus, comprising: a processor; and a memory coupled to the processor and having program instructions stored thereon which, when executed by the processor, cause the apparatus to: send a point-to-point protocol over Ethernet (PPPoE) message to an access gateway function (AGF) after establishing a packet data unit (PDU) session, wherein the PPPoE message is used in at least one of a PPPoE discovery process, an internet protocol control protocol (IPCP) process, or a link control protocol (LCP) process, and wherein the PPPoE message is encapsulated using one of a medium access control (MAC) address that is of the AGF and that corresponds to the PDU session or a MAC address that is of a user plane function (UPF) and that corresponds to a PPPoE session; and receive a PPPoE session identifier or an Internet Protocol (IP) address to establish a PPPoE connection between the apparatus and a network side device.

6. The apparatus according to claim 5, wherein the program instructions, when executed by the processor, further cause the apparatus to send a PDU session establishment request message to the AGF, wherein the PDU session establishment request message comprises: the PPPoE message; a manner for instructing the apparatus to obtain the IP address based on a PPPoE procedure; or information indicating a fixed network access type; or information indicating a fixed network service.

7. The apparatus according to claim 6, wherein the PDU session establishment request message is encapsulated in a non-access stratum (NAS) message, and wherein the NAS message is: encapsulated in a layer 2 data packet and identified using one of a virtual local area network (VLAN) label, a multiprotocol label switching (MPLS) label, the MAC address of the AGF, or an Ethernet type; encapsulated in a layer 3 data packet and identified using a user datagram protocol (UDP) port number or a predetermined destination IP address; encapsulated in the PPPoE session and identified using the PPPoE session identifier; encapsulated in a generic routing encapsulation (GRE) tunnel and identified using a GRE tunnel identifier; encapsulated in an extensible authentication protocol (EAP) message identified using an EAP parameter; or encapsulated in a predetermined protocol layer and identified using the predetermined protocol layer.

8. The apparatus according to claim 7, wherein the program instructions, when executed by the processor, further cause the apparatus to receive a PDU session establishment success message, and wherein the PDU session establishment success message comprises the MAC address that is of the AGF and that is assigned by the AGF to the PDU session, or wherein the PDU session establishment success message is encapsulated in the MAC address that is of the AGF and that is assigned by the AGF to the PDU session.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) To describe the technical solutions in the embodiments or the background of the present disclosure more clearly, the following describes the accompanying drawings required for the embodiments or the background of the present disclosure.

(2) FIG. 1 is a schematic architectural diagram of a 5G system according to an embodiment of the present disclosure;

(3) FIG. 2 is a schematic architectural diagram of a system of a 5G converged core network according to an embodiment of the present disclosure;

(4) FIG. 3A and FIG. 3B are schematic flowcharts of a method according to an embodiment of the present disclosure;

(5) FIG. 4 is a schematic structural diagram of a session management function device according to an embodiment of the present disclosure;

(6) FIG. 5 is a schematic structural diagram of a user plane function device according to an embodiment of the present disclosure;

(7) FIG. 6 is a schematic structural diagram of user equipment according to an embodiment of the present disclosure;

(8) FIG. 7 is a schematic structural diagram of an access network function device according to an embodiment of the present disclosure;

(9) FIG. 8 is a schematic structural diagram of a mobility management function according to an embodiment of the present disclosure;

(10) FIG. 9 is a schematic structuraL diagram of an electronic device according to an embodiment of the present disclosure; and

(11) FIG. 10 is a schematic structural diagram of user equipment according to an embodiment of the present disclosure.

DESCRIPTION OF EMBODIMENTS

(12) The embodiments of the present disclosure are described below with reference to the accompanying drawings in the embodiments of the present disclosure.

(13) FIG. 1 shows a system example of a 5G communications system. In FIG. 1, the 5G communications system includes a UE, a radio access network (RAN) or an access network (AN), a user plane function (UPF), a data network (DN), an AMF, an SMF, a policy control function (PCF), an application function (AF), an authentication server function (AUSF), and a unified data management (UDM). Interfaces N1 to N15 are respectively used for communication.

(14) FIG. 2 is a schematic diagram of a system of a 5G converged core network according to an embodiment of the present disclosure. Referring to a structure of the 5G communications system in FIG. 1, in FIG. 2, a dashed-line box part shows a next generation control plane function (NGCP). A fixed network AN is newly added to an access network side. At a location of CPE, the CPE may alternatively be UE, an RG, an FNRG, or a wireless fidelity (wifi) access point (AP). The fixed network AN communicates with the UPF through a n interface N3. In addition, in FIG. 2, the UPF may be mapped to a broadband network gateway-user plane function (BNG-UP), namely, a fixed network user plane function device. The AMF and the SMF are mapped to a broadband network gateway control plane function (BNG-CP) in a fixed network. The UDM is mapped to a bearer binding function (BBF) and an authentication, authorization and accounting (AAA) server in the fixed network. The PCF is mapped to a broadband policy control function (BPCF) in the fixed network. The CPE and the RAN may communicate with each other through a residential area network (NR) or an interface Uu. FIG. 2 includes a point-to-point protocol over Ethernet (PPPoE) session and a packet data unit (PDU) session. FIG. 2 further shows that the CPE sends a registration request to the AMF, and the UPF sends, to the SMF, information related to PPPoE and a dynamic host configuration protocol (DHCP). In FIG. 2, the fixed network user plane function (UPF) and a core network user plane function (CN-UPF) are combined.

(15) The AMF device, the SMF device, the UPF device, and the PCF device may be briefly referred to as an AMF, an SMF, a UPF, and a PCF respectively.

(16) As shown in FIG. 3A and FIG. 3B, based on the system of the 5G converged core network shown in FIG. 2, the following provides a schematic flowchart in which user equipment accesses a 5G CN through a fixed network. In FIG. 3A and FIG. 3B, an access gateway function (AGF) is an upper layer convergence point in the AN, is deployed on an access network side in the fixed network, and is mapped to the fixed network AN in FIG. 2.

(17) First, the CPE is registered with a network side, and a specific procedure in which the CPE is registered with the network side may comply with a current communications protocol. Details are not described herein.

(18) 301. The CPE initiates a PDU session related procedure using a non-access stratum (NAS) message.

(19) The PDU session related procedure may include a PDU session establishment request message, a PDU session modification message, a PDU session deletion message, or the like. The PDU session establishment request message is used as an example below for description.

(20) The PDU session establishment request message may include a user equipment identifier (CPE ID), a PDU session identifier (ID), a network identifier (for example, a digital data network (DDN)), slice information, a type identifier, and the like.

(21) The network identifier may be set to a fixed network service identifier, for example, a web television (IPTV) service.

(22) The slice information may be set to a slice identifier related to the fixed network.

(23) The type identifier may be an Internet Protocol (IP) address obtaining manner, a session type parameter, or the like. The IP address obtaining manner is a manner in which the CPE receives an IP address. The session type parameter is used to notify the network side of the manner in which the CPE obtains the IP address. The CPE may set the type identifier based on a service and configuration information. For example, if the CPE senses, through a port, that an IPTV is online, the IP address may be obtained for this type of service based on an internet protocol over Ethernet (IPoE). In this case, the CPE may set the type identifier to DHCP, a manner in which IP address obtaining is deferred, an IPoE obtaining manner, or the like. If the CPE senses, through a port, that a personal computer (PC) is online, the CPE sets the type identifier to a PPPoE, an Ethernet type, an unstructured type, or the like based on the configuration information.

(24) A function of the type identifier is to notify the network side of the IP address obtaining manner, to be specific, to notify the network side of a manner in which the IP address corresponding to a PDU session is sent to the CPE. The type identifier belongs to optional information. If the CPE does not send the type identifier, or the CPE sends the type identifier but the network side does not use the type identifier, the SMF may obtain, from the PCF, the manner in which the IP address is sent to the CPE. The PCF may determine, based on a fixed network access type and/or a service type that are/is received from the SMF, the manner in which the IP address is sent to the CPE, and notify the SMF of the manner. The type identifier may be defined as an IP address index.

(25) The CPE may encapsulate the NAS message in a Layer 2 (L2) or Layer 3 (L3) data packet. A specific implementation solution is as follows.

(26) L2 encapsulation solution: The CPE encapsulates the NAS message in an Ethernet packet, and uses a special virtual local area network (VLAN) label to indicate that the Ethernet packet includes the NAS message. The special VLAN label may be pre-configured on a CPE side and an AGF side, and is used to encapsulate and identify the NAS message.

(27) L3 encapsulation solution: The CPE encapsulates the NAS message in an IP packet/a user datagram protocol (UDP) packet, and encapsulates a NAS data packet using a special UDP port number or a special IP address, and the AGF identifies the NAS message based on the special UDP port number or the special IP address.

(28) A manner in which the CPE encapsulates the NAS message and content included in the NAS message may also have other examples in the summary. As an application example, this embodiment should not be construed as a uniqueness limitation on this embodiment of the present disclosure.

(29) 302. The AGF forwards the NAS message to the AMF through an interface N2.

(30) An N2 interface message may be an initial user equipment message, an uplink NAS transmission message, or the like. This is not limited in this embodiment of the present disclosure.

(31) Optionally, the AGF may send a circuit number (Circuit ID) to the AMF.

(32) A FAN at a first layer, namely, the FAN closest to a residential gateway, identifies the circuit number. For example, a port to which a cable of the residential gateway is connected is the circuit number. The FAN at the first layer adds this para meter to the forwarded message, and then sends the para meter to the AGF along with the message level by level.

(33) An implementation in which the AGF sends the circuit number to the AMF may be as follows.

(34) A. As shown in step 301, the fixed access network (FAN) identifies the NAS message based on L2 or L3 information. The FAN adds the circuit ID to the NAS message, or adds the circuit ID to a NAS message header. The AGF forwards, to the AMF, the NAS message to which the circuit ID is added.

(35) B. The AGF obtains the circuit identifier, and the AGF adds the circuit ID to the sent N2 interface message.

(36) A solution in which the AGF obtains the circuit ID is not limited in this embodiment of this application. For example, the AGF may further obtain the circuit ID based on the configuration information.

(37) 303. The AMF selects the SMF after receiving the NAS message.

(38) The AMF may select the SMF based on at least one of slice information, network information, or a type identifier. For example, when the type identifier is a PPPoE type, the AMF may select an SMF that supports PPPoE processing.

(39) 304. The AMF forwards the NAS message to the SMF using an N11 interface message.

(40) The NAS message is a PDU session establishment request message based on the foregoing example. A manner in which the AMF sends the NAS message may be as follows: forwarding the PDU session establishment request message to the SMF using an N11 interface message. A name of the N11 interface message is not limited in this embodiment of this application. The N11 interface message is a session request message, or the like.

(41) If the AMF does not obtain the circuit ID in steps 301 and 302, the AMF may instruct the SMF to establish a restricted PDU session. For example, the AMF may send a session restriction indication or a restricted PDU type to the SMF. The restricted PDU session is a PDU session in which a data packet cannot be forwarded to an external network. The data packet cannot be forwarded because the IP address has not been assigned to the CPE, or the data packet of the PDU session can only be cached or discarded even if the IP address is assigned. Correspondingly, an unrestricted PDU session is a normal session, and a data packet received from the PDU session is forwarded to the external network based on a destination IP address. Instructing the SMF to establish the restricted PDU session is content that is optionally executed. Therefore, the restricted session indication and the restricted PDU type belong to an optional parameter.

(42) 305. After receiving the NAS message, the SMF selects the UPF, and sends an N4 interface message to the UPF.

(43) The N4 interface message includes packet detection information (PDI). When the type identifier is the PPPoE type, the SMF sends PPPoE packet detection information to the UPF. For example, the PDI includes a PPPoE message type indication, and the PPPoE message type indication includes two parts:

(44) 1. A PPPoE discovery packet matches an Ethernet type 0x8863. Optionally, based ona type included in a PPPoE packet header, the PPPoE discovery packet is further specified as a packet sent by a PPPoE user. For example, the type is a PPPoE initiation (PADI) type, a PPPoE request (PADR) type, a PPPoE terminate (PADT) type.

(45) 2. A PPPoE session phase packet matches an Ethernet type 0x8864, and a type in a PPPoE packet header is not 0x0021 (is not an Internet Protocol version 4 (IPv4)). Optionally, a message type is further specified as a link control protocol (LCP), a network control protocol (NCP), an IPCP, a challenge handshake authentication protocol (CHAP), a password authentication protocol (PAP), or the like.

(46) Optionally, a PPPoE session ID may be further specified as an ID assigned in a PPPoE discovery process. The PDI may be used to instruct the UPF to detect L2 information of a data packet. When a type parameter that is in the data packet and that is included in an Ethernet packet header matches a PPPoE message type in the PDI, the UPF sends the matched data packet to the SMF.

(47) In addition, if a current PDU session is the restricted PDU session, the SMF instructs the UPF to store or discard another service data packet received on the PDU session. The “another service data packet” is a data packet other than the matched data packet.

(48) There are the following two processing solutions (A) or (B).

(49) The solution (A) is as follows.

(50) 306A. The SMF sends an N11 interface reply message, where the N11 interface reply message includes a PDU session establishment success (PDU session establishment accept) message and PDU session information.

(51) The PDU session establishment success message may include an authorized quality of service (QoS) policy, a service continuity mode, and the like. The PDU session information may include a PDU session identifier, a QoS file, and core network tunnel identification information.

(52) 307A. The AMF sends, to the AGF through the interface N2, the PDU session establishment success message and the PDU session information that are received in step 306A, and the AGF sends the PDU session establishment success message to the CPE.

(53) For example, the AGF parses the PDU session information to obtain the PDU session identifier. The AGF assigns a special AGF medium access control (MAC) address to the PDU session, and encapsulates the PDU session establishment success message using the MAC address as an AGF source address. The AGF MAC address herein is special because a binding relationship is established between the AGF MAC address and the PDU session, and may also be referred to as a dedicated AGF MAC address.

(54) Herein, the CPE may obtain, from an L2 source MAC address in the PDU session establishment success message, the AGF MAC address corresponding to the PDU session. The CPE may store a correspondence between the PDU session identifier and the special AGF MAC address.

(55) 308A. The AGF may further store the core network side tunnel identification information in the PDU session information, and assign a tunnel identifier of the AGF, in other words, assign an AGF tunnel identifier. Then, the AGF sends the AGF tunnel identifier to the AMF using the N2 interface message.

(56) 309A. The AMF forwards the AGF tunnel identifier to the SMF, and the SMF forwards the AGF tunnel identifier to the UPF, to update tunnel information. Therefore, a user plane tunnel establishment procedure between the UPF and the AGF is completed.

(57) The solution (B) is as follows.

(58) 306B. The SMF sends an N11 interface reply message, where the N11 interface reply message includes PDU session information.

(59) The PDU session information may include a PDU session identifier, a QoS file, core network tunnel identification information, and the like.

(60) 307B. The AMF sends the PDU session information to the AGF. The AGF assigns an AGF tunnel identifier. In addition, the AGF obtains the PDU session identifier in the PDU session information, and the AGF assigns a special AGF MAC address to the PDU session.

(61) 308B. The AGF sends the assigned AGF tunnel identifier and special AGF MAC address to the AMF, and the AMF forwards the assigned AGF tunnel identifier and special AGFMAC address to the SMF.

(62) 309B. The SMF sends the AGF tunnel identifier to the UPF, to update tunnel information.

(63) 310B. The SMF generates a PDU session establishment success message, and sends the PDU session establishment success message to the CPE using the AMF and the AGF. The PDU session establishment success message includes an AGF MAC address, and may further include a PDU session identifier.

(64) The CPE obtains, from the PDU session establishment success message, the AGF MAC address corresponding to the PDU session. The CPE stores a correspondence between the PDU session identifier and the AGF MAC address.

(65) 311. The CPE initiates a PPPoE procedure or initiates a DHCP procedure to obtain a CPE IP address.

(66) The PPPoE procedure is used as an example. The CPE sends a PPPoE discovery process message, an LCP message, or an NCP request message to the AGF, and encapsulates a PPPoE message using the AGF MAC address corresponding to the PDU session. The NCP has different names according to different protocols, and has a same function as the IPCP.

(67) The FAN may add the circuit ID of the CPE to the PPPoE message and send the PPPoE message to the AGF. Specifically, the FAN may add the circuit ID of the CPE to the PPPoE discovery process message and send the PPPoE discovery process message to the AGF. The AGF may map the AGF MAC address to the PDU session, and send the PPPoE message to the UPF corresponding to the PDU session.

(68) 312. The UPF identifies a PPPoE message based on the PDI, and sends the identified PPPoE message to the SMF.

(69) Similarly, a DHCP message may also be identified.

(70) 313. The SMF obtains at least one of a circuit ID, a user equipment identifier, a user name, or a user name password included in the PPPoE message, and sends the foregoing information to an authentication function entity. The authentication function entity performs authentication on the CPE based on the at least one of the circuit ID, the user equipment identifier, the user name, or the user name password. For the CPE on which authentication succeeds, the SMF updates a data packet forwarding rule. For example, the SMF may instruct the UPF to normally forward a data packet.

(71) Alternatively, the SMF sends the at least one of the circuit ID, the user equipment identifier, the user name, or the user name password to the AMF, and the AMF performs authentication on the CPE based on the foregoing information. For the CPE on which authentication succeeds, the AMF instructs the SMF to establish the unrestricted PDU session. The SMF updates the data packet forwarding rule according to an indication of the AMF, and instructs the UPF to normally forward the data packet.

(72) In addition, for the CPE on which authentication succeeds, the SMF may assign a PPPoE session ID and a CPE IP address, and send the PPPoE session ID and the CPE IP address to the CPE in the PPPoE procedure.

(73) 314. The UPF obtains and stores the PPPoE session ID sent by the SMF. The UPF forwards the PPPoE message to the CPE, and the CPE obtains, in the PPPoE procedure, the PPPoE session ID and the CPE IP address that are assigned by the SM F. The CPE subsequently encapsulates a service data packet using the PPPoE session ID and the CPE IP address.

(74) An embodiment of the present disclosure further provides a session management function device. As shown in FIG. 4, the session management function device includes: an obtaining unit 401 configured to obtain a point-to-point protocol over Ethernet (PPPoE) message sent by user equipment; an assignment unit 402 configured to assign a PPPoE session identifier and/or an IP address to the user equipment; and a sending unit 403 configured to send the assigned PPPoE session identifier and/or IP address to the user equipment, to establish a PPPoE connection between the user equipment and a network side device.

(75) Herein, the session management function may further include a connection establishment unit 404 configured to establish a PPPoE connection between the user equipment and the session management function (SMF).

(76) The sending unit 403 is further configured to, before the PPPoE message is obtained, send a request message to a user plane function (UPF), where the request message is used to instruct the UPF to send the obtained PPPoE message to the session management function SMF.

(77) Alternatively, the session management function further includes: a receiving unit 405 configured to, before the PPPoE message is obtained, receive a non-access stratum (NAS) request message sent by the user equipment, where the NAS request message includes the PPPoE message.

(78) Optionally, that the request message is used to instruct the UPF to send the obtained PPPoE message to the SMF includes that the request message includes packet detection information (PDI), and the PDI is used to instruct the UPF to identify a data packet in which a type parameter that is in the data packet and that is included in an Ethernet packet header matches a PPPoE message type included in the PDI, and to send the matched data packet to the SMF; or the request message includes PDI and a forwarding action rule (FAR), the PDI is used to instruct the UPF to identify a data packet in which a type parameter that is in the data packet and that is included in an Ethernet packet header matches a PPPoE message type included in the PDI, and the forwarding action rule is used to instruct to send the matched data packet to the SMF.

(79) Optionally, that the PDI is used to instruct the UPF to identify the type parameter that is in the data packet and that is included in the Ethernet packet header includes the following.

(80) The PDI is used to instruct the UPF to identify layer 2 information of the data packet, to obtain the type parameter included.in the Ethernet packet header.

(81) Optionally, that a sending unit 403 is configured to send the assigned PPPoE session identifier and/or IP address to the user equipment includes: encapsulating the PPPoE session identifier and/or the IP address in the PPPoE message, and sending the PPPoE message to the user equipment; or sending the assigned PPPoE session identifier and/or IP address to the user equipment using a NAS message.

(82) The sending unit 403 is further configured to, if encapsulating the PPPoE session identifier and/or the IP address in the PPPoE message, encapsulate the PPPoE message using a medium access control (MAC) address of the UPF as a source MAC address; and send the encapsulated PPPoE message to the user equipment using the UPF.

(83) The obtaining unit 401 is further configured to receive a data packet that is sent by the UPF and that includes the PPPoE message, and obtain at least one of a circuit number, a user equipment identifier, a user name, and a user password from the PPPoE message. Alternatively, the abtaining unit is configured to receive at least one of a circuit number, a user equipment identifier, a user name, or a user password that are sent by the UPF. Alternatively, the abtaining unit is configured to obtain at least one of a circuit number, a user equipment identifier, a user name, or a user password from the NAS message.

(84) The sending unit 403 is further configured to send the at least one of the circuit number, the user equipment identifier, the user name, or the user password to an access and mobility management function (AMF) and/or an authentication entity.

(85) Optionally, that an assignment unit 402 is configured to assign a PPPoE session identifier and/or an IP address to the user equipment includes assigning the PPPoE session identifier and/or the IP address to the user equipment according to an indication of the AMF or an indication of the authentication entity.

(86) The session management function device further includes: a receiving unit 405 configured to, before the SMF obtains the PPPoE message sent by the user equipment, receive a packet data unit (PDU) session establishment request message, where the PDU session establishment request message includes a manner used to instruct the user equipment to obtain the IP address based on a PPPoE procedure, or includes information used to indicate a fixed network access type, or includes information used to indicate a fixed network service; or receive an IP index sent by a policy control function PCF, where the IP index is used to indicate a manner in which the user equipment obtains the IP address based on a PPPoE procedure.

(87) The session management function device further includes the following.

(88) The receiving unit 405 is configured to receive a MAC address that is of an access gateway function (AGF) and that is assigned by the AGF to a PDU session of the user equipment.

(89) The sending unit 403 is further configured to send a PDU session establishment success message to the user equipment, where the PDU session establishment success message includes the MAC address of the AGF.

(90) The receiving unit 405 is further configured to: if the request message is used to instruct the UPF to send the obtained PPPoE message to the SMF, after the PDU session establishment success message is sent to the user equipment, receive the PPPoE message that is from the user equipment and that is sent by the UPF, where the PPPoE message is used in a PPPoE discovery process, an internet protocol control protocol (I PCP) process, or a link control protocol (LCP) process.

(91) An embodiment of the present disclosure further provides a user plane function device. As shown in FIG. 5, the user plane function device includes: a receiving unit 501 configured to receive a request message from an SMF; an information obtaining unit 502 configured to: obtain a PPPoE message based on the request message; and obtain a PPPoE session identifier and/or an IP address that are/is assigned to user equipment that sends the PPPoE message; and a sending unit 503, configured to send the PPPoE session identifier and/or the IP address to the user equipment, to establish a PPPoE connection between the user equipment and a network side device.

(92) The user plane function device may further include a connection establishment unit 504 configured to establish a PPPoE connection between the user equipment and the user plane device.

(93) Optionally, the request message includes that the request message is used to instruct the UPF to send the obtained PPPoE message to the SMF; or the request message is used to instruct the UPF to obtain the PPPoE message; or the request message carries the PPPoE message sent to the UPF.

(94) Optionally, if the request message is used to instruct the UPF to obtain the PPPoE message, the request message is further used to instruct to send, to the SMF, at least one of a circuit number, a user equipment identifier, a user name, and a user password that are carried in the PPPoE message.

(95) Optionally, that the request message is used to instruct the UPF to obtain the PPPoE message includes that the request message includes PDI, and the PDI is used to instruct the UPF to identify a data packet in which a type parameter in the data packet matches a PPPoE message type included in the PDI, and to forward the identified data packet in the PPPoE message type to the SMF.

(96) Optionally, the information obtaining unit 502 is configured to: if the request message is used to instruct the UPF to send the obtained PPPoE message to the SMF, receive the PPPoE message sent by the SMF, where the PPPoE message includes the PPPoE session identifier and/or the IP address.

(97) Optionally, in the PPPoE message, a MAC address of the UPF is a source MAC address.

(98) Optionally, the information obtaining unit 502 is configured to: if the request message is used to instruct the UPF to obtain the PPPoE message, or if the request message carries the PPPoE message sent to the UPF, assign the PPPoE session identifier and/or the IP address to the user equipment based on the request message.

(99) The sending unit 503 is configured to send a PPPoE reply message to the user equipment; and send the assigned PPPoE session identifier and/or IP address to the user equipment using the PPPoE reply message.

(100) The receiving unit 501 is further configured to receive at least one of a circuit number, a user equipment identifier, a user name, or a user password that are sent by the SMF.

(101) The sending unit 503 is further configured to send the at least one of the circuit number, the user equipment identifier, the user name, or the user password to an authentication entity for authentication.

(102) An embodiment of the present disclosure further provides user equipment. As shown in FIG. 6, the user equipment includes: a sending unit 601 configured to: after a packet data unit PDU session is established, send a PPPoE message to an AGF, where the PPPoE message is used in at least one of a PPPoE discovery process, an IPCP process, or an LCP process, and the PPPoE message is encapsulated using a MAC address that is of the AGF and that corresponds to the PDU session, or the PPPoE message is encapsulated using a MAC address that is of a UPF and that corresponds to a PPPoE session; and a receiving unit 602 configured to receive a PPPoE session identifier or an IP address, to establish a PPPoE connection between the user equipment and a network side device.

(103) The sending unit 601 is further configured to: before sending the PPPoE message to the AGF, send a PDU session establishment request message to the AGF, where the PDU session establishment request message includes the PPPoE message. Alternatively, the PDU session establishment request message includes a manner used to instruct the user equipment to obtain the IP address based on a PPPoE procedure, or includes information used to indicate a fixed network access type, or includes information used to indicate a fixed network service.

(104) Optionally, the PDU session establishment request message is encapsulated in anon-access stratum (NAS) message.

(105) The NAS message is encapsulated in a layer 2 data packet, and the NAS message is identified using a virtual local area network (VLAN) label, a multiprotocol label switching (MPLS) label, or the MAC address of the AGF, or the NAS message is identified using an Ethernet type.

(106) Alternatively, the NAS message is encapsulated in a layer 3 data packet, and the NAS message is identified using a UDP port number or a predetermined destination IP address.

(107) Alternatively, the NAS message is encapsulated in the PPPoE session, and the PPPoE session identifier is used to identify the NAS message.

(108) Alternatively, the NAS message is encapsulated in a GRE tunnel, and a GRE tunnel identifier is used to identify the NAS message.

(109) Alternatively, the NAS message is encapsulated in an EAP message, and the NAS message is identified using an EAP parameter.

(110) Alternatively, the NAS message is encapsulated in a predetermined protocol layer, and the NAS message is identified using the predetermined protocol layer.

(111) The receiving unit 602 is further configured to receive a PDU session establishment success message returned by the AGF or an SMF, where the PDU session establishment success message includes the MAC address that is of the AGF and that is assigned by the AGF to the PDU session, or the PDU session establishment success message is encapsulated in the MAC address that is of the AGF and that is assigned by the AGF to the PDU session.

(112) The receiving unit 602 is further configured to receive a PPPoE reply message, where the PPPoE reply message includes the MAC address that is of the UPF and that corresponds to the PPPoE session.

(113) An embodiment of the present disclosure further provides an access gateway function device. As shown in FIG. 7, the access gateway function device includes: a receiving unit 701 configured to receive a PPPoE message sent by user equipment, where the PPPoE message is used in a PPPoE discovery process, an IPCP process, or an LCP process, and the PPPoE message is encapsulated using a MAC address of the AGF or a MAC address of a UPF; a session determining unit 702 configured to determine a packet data unit PDU session corresponding to the MAC address of the AGF; and a sending unit 703 configured to: forward the PPPoE message to the UPF corresponding to the PDU session; or send the PPPoE message to the UPF based on the MAC address of the UPF, where the receiving unit 701 is further configured to receive a PPPoE session identifier and/or an IP address; and the sending unit 703 is further configured to forward the PPPoE session identifier and/or the IP address to the user equipment, such that the user equipment establishes a PPPoE connection to a network side device.

(114) The receiving unit 701 is further configured to, before receiving the PPPoE message sent by the user equipment, receive a PDU session establishment request message sent by the user equipment, where the PDU session establishment request message includes a manner used to instruct the user equipment to obtain the IP address based on a PPPoE procedure, or includes information used to indicate a fixed network access type, or includes information used to indicate a fixed network service.

(115) The sending unit 703 is further configured to forward the PDU session establishment request message to an AMF.

(116) Optionally, the PDU session establishment request message is encapsulated in an NAS message.

(117) The NAS message is encapsulated in a layer 2 data packet, and the NAS message is identified using a VLAN label, a MPLS label, or the MAC address of the AGF, or the NAS message is identified using an Ethernet type.

(118) Alternatively, the NAS message is encapsulated in a layer 3 data packet, and the NAS message is identified using a UDP port number or a predetermined destination IP address.

(119) Alternatively, the NAS message is encapsulated in a PPPoE session, and the PPPoE session identifier is used to identify the NAS message.

(120) Alternatively, the NAS message is encapsulated in a GRE tunnel, and a GRE tunnel identifier is used to identify the NAS message.

(121) Alternatively, the NAS message is encapsulated in an EAP message, and the NAS message is identified using an EAP parameter.

(122) Alternatively, the NAS message is encapsulated in a predetermined protocol layer, and the NAS message is identified using the predetermined protocol layer.

(123) The sending unit 703 is further configured to forward the NAS message, where the NAS message includes a number of a circuit accessed by the user equipment.

(124) The access gateway function device further includes an address assignment unit 704 configured to assign the MAC address of the AGF to the PDU session, where the sending unit 703 is further configured to send the assigned MAC address of the AGF to the user equipment.

(125) Optionally, that the sending unit 703 is configured to send the assigned MAC address of the AGF to the user equipment includes: encapsulating a PDU session establishment success message using the MAC address of the AGF, and sending the PDU session establishment success message to the user equipment; or sending the MAC address of the AGF to an SMF, such that the SMF adds the MAC address of the AGF to the PDU session establishment success message, and sends the PDU session establishment success message to the user equipment.

(126) An embodiment of the present disclosure further provides a mobility management function device. As shown in FIG. 8, the mobility management function device includes: a receiving unit 801 configured to receive a packet data unit (PDU) session establishment request message sent by an AGF, where the PDU session establishment request message includes a manner used to instruct user equipment to obtain an IP address based on a PPPoE procedure, or includes information used to indicate a fixed network access type, or includes information used to indicate a fixed network service, where the receiving unit 801 is further configured to receive a PDU session establishment success message returned by an SMF; and a sending unit 802 configured to send the PDU session establishment success message to the user equipment using the AGF.

(127) Alternatively, the receiving unit 801 is configured to receive a MAC address that is of the AGF and that is assigned by the AGF to a PDU session. The sending unit 802 is configured to send the MAC address of the AGF to the SMF.

(128) The mobility management function device further includes a selection unit 803 configured to select the SMF according to the indication information in the PDU session establishment request message, where the sending unit 802 is further configured to send the PDU session establishment request message to the SMF.

(129) The sending unit 802 is further configured to send an instruction to the SMF, to instruct the SMF to obtain at least one of a circuit number, a user equipment identifier, a user name, or a user password.

(130) The receiving unit 801 is further configured to: after the instruction is sent to the SMF, receive the at least one of the circuit number, the user equipment identifier, the user name, or the user password that are sent by the SMF.

(131) The sending unit 802 is further configured to send the at least one of the circuit number, the user equipment identifier, the user name, or the user password to an authentication entity.

(132) The sending unit 802 is further configured to: when authentication on the user equipment succeeds, indicate, to the SMF, that authentication on the user equipment succeeds.

(133) FIG. 9 shows an electronic device 90 according to an embodiment of the present disclosure. The electronic device 90 includes a processor 901, a memory 902, and a transceiver 903. The processor 901, the memory 902, and the transceiver 903 may be interconnected using a bus.

(134) The memory 902 includes but is not limited to a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), or a compact disc read-only memory (CD-ROM). The memory 902 is configured to store related instructions and data. The transceiver 903 is configured to receive and send data. Therefore, in this embodiment, the transceiver 903 may be mapped to the sending unit and the receiving unit in the foregoing embodiments, and a function of another unit may be mapped to a function of the processor 901.

(135) The processor 901 may be one or more central processing units (CPU). When the processor 901 is one CPU, the CPU may be a single-core CPU or a multi-core CPU.

(136) The processor 901 in the device 90 is configured to read program code stored in the memory 902, to perform the steps in the methods in the foregoing method embodiments or the summary. Details are not described herein again.

(137) The electronic device 90 may be an entity device such as user equipment, an AGF, or an AMF in this embodiment of the present disclosure. This depends on specific content performed by the electronic device 90.

(138) In an example, FIG. 10 shows an example of a hardware structure of user equipment. For ease of description, FIG. 10 shows only a part related to this embodiment of the present disclosure. For technical details that are not disclosed, refer to the method part in this embodiment of the present disclosure. The user equipment may be any user equipment including a mobile phone, a tablet computer, a PDA (Personal Digital Assistant), a POS (Point of Sales), a nin-vehicle computer, or the like. For example, the user equipment is the mobile phone.

(139) FIG. 10 is a block diagram of a partial structure of a mobile phone related to the user equipment provided in this embodiment of the present disclosure. Referring to FIG. 10, the mobile phone includes components such as a radio frequency (RF) circuit 1010, a memory 1020, an input unit 1030, a display unit 1040, a sensor 1050, an audio circuit 1060, a wireless fidelity (WiFi) module 1070, a processor 1080, and a power supply 1090. A person skilled in the art may understand that the structure of the mobile phone shown in FIG. 10 constitutes no limitation on the mobile phone. The mobile phone may include more or fewer components than those shown in the figure, may combine some components, or may have different component arrangements.

(140) The following describes each constituent component of the mobile phone in detail with reference to FIG. 10.

(141) The RF circuit 1010 may be configured to receive and send a signal in an information receiving and sending process or a call process. In particular, the RF circuit 1010 receives downlink information from a base station, and then sends the downlink information to the processor 1080 for processing. In addition, the RF circuit 1010 sends related uplink data to the base station. Usually, the RF circuit 1010 includes but is not limited to an antenna, at least one amplifier, a transceiver, a coupler, a low noise amplifier (LNA), a duplexer, and the like. In addition, the RF circuit 1010 may further communicate with a network and another device through wireless communication. Any communications standard or protocol may be used for the wireless communication, including but not limited to a global system for mobile communications (GSM), a general packet radio service (GPRS), a code division multiple access (CDMA) system, a wideband code division multiple access (WCDMA) system, a long term evolution (LTE) system, an email, a short message service (SMS), and the like.

(142) The memory 1020 may be configured to store a software program and a module. The processor 1080 performs various function applications of the mobile phone and data processing by running the software program and the module that are stored in the memory 1020. The memory 1020 may mainly include a program storage area and a data storage area. The program storage area may store an operating system, an application program required by at least one function (for example, a sound play function and an image play function), and the like. The data storage area may store data (for example, audio data and an address book) created based on use of the mobile phone, and the like. In addition, the memory 1020 may include a high speed random access memory, and may further include a nonvolatile memory, for example, at least one magnetic disk storage device, a flash memory device, or another volatile solid-state storage device.

(143) The input unit 1030 may be configured to: receive entered number or character information; and generate a key signal input related to a user setting and function control of the mobile phone. Specifically, the input unit 1030 may include a touch panel 1031 and other input devices 1032. The touch panel 1031, also referred to as a touchscreen, may collect a touch operation (for example, an operation performed by a user on or near the touch panel 1031 using any proper object or accessory such as a finger or a stylus) performed by the user on or near the touch panel 1031, and drive a corresponding connection apparatus based on a preset program. Optionally, the touch panel 1031 may include two parts: a touch detection apparatus and a touch controller. The touch detection apparatus detects a touch direction of the user, detects a signal brought by the touch operation, and transmits the signal to the touch controller. The touch controller receives touch information from the touch detection apparatus, converts the touch information into touch coordinates, then sends the touch coordinates to the processor 1080, and can receive and execute a command sent by the processor 1080. In addition, the touch panel 1031 may be implemented in a plurality of types, such as a resistive type, a capacitive type, an infrared type, and a surface acoustic wave type. The input unit 1030 may include the other input devices 1032 in addition to the touch panel 1031. Specifically, the other input devices 1032 may include but are not limited to one or more of a physical keyboard, a function key (for example, a volume control key or an on/off key), a trackball, a mouse, a joystick, and the like.

(144) The display unit 1040 may be configured to display information entered by the user or information provided for the user, and various menus of the mobile phone. The display unit 1040 may include a display panel 1041. Optionally, the display panel 1041 may be configured in a form of a liquid crystal display (LCD), an organic light-emitting diode (OLED), or the like. Further, the touch panel 1031 may cover the display panel 1041. After detecting the touch operation on or near the touch panel 1031, the touch panel 1031 transmits the touch operation to the processor 1080 to determine a type of a touch event, and then the processor 1080 provides a corresponding visual output on the display panel 1041 based on the type of the touch event. In FIG. 10, the touch panel 1031 and the display panel 1041 are used as two independent components to implement input and output functions of the mobile phone. However, in some embodiments, the touch panel 1031 and the display panel 1041 may be integrated to implement the input and output functions of the mobile phone.

(145) The mobile phone may further include at least one sensor 1050, for example, a light sensor, a motion sensor, and another sensor. Specifically, the light sensor may include an ambient light sensor and a proximity sensor. The ambient light sensor may adjust luminance of the display panel 1041 based on brightness of ambient light. The proximity sensor may turn off the display panel 1041 and/or backlight when the mobile phone approaches to an ear. As a type of motion sensor, an accelerometer sensor may detect values of acceleration in all directions (usually, three axes), may detect a value and a direction of gravity when the accelerometer sensor is static, and may be used in an application that identifies a mobile phone posture (such as screen switching between a landscape mode and a portrait mode, a related game, or magnetometer posture calibration), a function related to vibration identification (such as a pedometer or a strike), and the like. Other sensors such as a gyroscope, a barometer, a hygrometer, a thermometer, and an infrared sensor may be further configured in the mobile phone. Details are not described herein.

(146) The audio circuit 1060, a speaker 1061, and a microphone 1062 may provide an audio interface between the user and the mobile phone. The audio circuit 1060 may convert received audio data into an electrical signal, and transmit the electrical signal to the speaker 1061, and the speaker 1061 converts the electrical signal into a sound signal for output. In addition, the microphone 1062 converts a collected sound signal into an electrical signal. The audio circuit 1060 receives the electrical signal, converts the electrical signal into audio data, and then outputs the audio data to the processor 1080 for processing. The processor 1080 sends the audio data to, for example, another mobile phone using the RF circuit 1010, or outputs the audio data to the memory 1020 for further processing.

(147) WiFi belongs to a short-distance wireless transmission technology. The mobile phone may help, using the WiFi module 1070, the user receive and send an email, browse a web page, access streaming media, and the like. The WiFi module 1070 provides wireless broadband internet access for the user. Although FIG. 10 shows the WiFi module 1070, it may be understood that the WiFi module 1070 is not a mandatory component of the mobile phone, and may be completely omitted based on a requirement without changing the essence of the present disclosure.

(148) The processor 1080 is a control center of the mobile phone, connects each part of the entire mobile phone using various interfaces and lines, and performs various functions of the mobile phone and data processing by running or executing the software program and/or the module that are/is stored in the memory 1020 and invoking data stored in the memory 1020, to perform overall monitoring on the mobile phone. Optionally, the processor 1080 may include one or more processing units. Preferably, an application processor and a modem processor may be integrated into the processor 1080. The application processor mainly processes an operating system, a user interface, an application program, and the like. The modem processor mainly processes wireless communication. It may be understood that the modem processor may alternatively not be integrated into the processor 1080.

(149) The mobile phone further includes the power supply 1090 (for example, a battery) supplying power to the components. Preferably, the power supply 1090 may be logically connected to the processor 1080 using a power management system, to implement functions such as management of charging, discharging, and power consumption using the power management system.

(150) Although not shown, the mobile phone may further include a camera, a Bluetooth module, and the like. Details are not described herein.

(151) In this embodiment of the present disclosure, the processor 1080 included in the user equipment has a function corresponding to the processor 901 in the foregoing embodiment, and the RF circuit 1010 and the WiFi module 1070 may be mapped to functions of the sending unit and the receiving unit of the user equipment. For detailed descriptions of the executed functions, refer to the method embodiment and the apparatus embodiment of the user equipment. Details are not described herein again.

(152) An embodiment of the present disclosure further provides a computer program product. The computer program product includes an executable instruction, and when the executable instruction is executed, any method procedure provided in the embodiments of the present disclosure is implemented.

(153) An embodiment of the present disclosure further provides a computer storage medium. The computer storage medium includes an executable instruction, and when the executable instruction is executed, any method procedure in the embodiments of the present disclosure is implemented. A person of ordinary skill in the art may understand that all or some of the procedures of the methods in the embodiments may be implemented by a computer program instructing related hardware. The program may be stored in a computer readable storage medium. When the program is executed, the procedures in the method embodiments may be included. The foregoing storage medium includes any medium that can store program code, for example, a ROM, a random access memory RAM, a magnetic disk, or an optical disk.