Multicast communication method, and apparatus and system

1. A communication method comprising:

receiving, by a user plane function network element, a multicast packet, wherein the multicast packet comprises a multicast address;

matching, by the user plane function network element, the multicast packet with one or more packet detection rules (PDRs) on the user plane function network element; and

when the multicast packet successfully matches a first PDR of the one or more PDRs, and the first PDR indicates to continue matching the multicast packet with another PDR, continuing, by the user plane function network element, matching the multicast packet with a second PDR of the one or more PDRs.

2. The method according to claim 1 , wherein the method further comprises:

when packet duplication skip information corresponding to the first PDR does not match sender information of the multicast packet, duplicating, by the user plane function network element, the multicast packet, and processing, by the user plane function network element, a duplicated multicast packet according to a rule associated with the first PDR; or

when the packet duplication skip information corresponding to the first PDR matches the sender information of the multicast packet, skipping, by the user plane function network element, processing the multicast packet according to a rule associated with the first PDR.

3. The method according to claim 2 , wherein,

that the packet duplication skip information corresponding to the first PDR matches the sender information of the multicast packet comprises:

the packet duplication skip information corresponding to the first PDR is same as the sender information of the multicast packet; and

that the packet duplication skip information corresponding to the first PDR does not match the sender information of the multicast packet comprises:

the packet duplication skip information corresponding to the first PDR is different from the sender information of the multicast packet.

4. The method according to claim 2 , wherein the multicast packet comprises the sender information of the multicast packet, and the sender information of the multicast packet comprises address information of a terminal device that sends the multicast packet.

5. The method according to claim 2 , wherein the method further comprises:

receiving, by the user plane function network element, the sender information of the multicast packet, wherein the sender information of the multicast packet comprises N19 indication information or N6 indication information.

6. The method according to claim 5 , wherein the N6 indication information or the N19 indication information is comprised in general packet radio service (GPRS) tunneling protocol-user plane (GTP-U) tunnel header information.

7. The method according to claim 1 , wherein the matching, by the user plane function network element, the multicast packet with the one or more PDRs on the user plane function network element comprises:

determining, by the user plane function network element, an N4 session that matches the multicast packet and that is on the user plane function network element; and

matching, by the user plane function network element, the multicast packet with each of PDRs in the N4 session in descending order of priorities of the PDRs.

8. The method according to claim 1 , wherein the first PDR comprises a type indication, an indication to continue matching, packet duplication information, or packet duplication skip information, and the type indication, the indication to continue matching, the packet duplication information, or the packet duplication skip information indicates to continue matching another PDR.

9. The method according to claim 1 , wherein the method further comprises:

receiving, by the user plane function network element, an N4 session identifier and the first PDR from a session management function network element, wherein the first PDR is used to detect the multicast packet; and

configuring, by the user plane function network element, the first PDR in a N4 session corresponding to the N4 session identifier.

10. The method according to claim 1 , wherein the multicast packet is a broadcast packet, and the multicast address is a broadcast address; or the multicast packet comprises a groupcast packet, and the multicast address is a groupcast address.

11. A communications apparatus, comprising:

at least one processor; and

a non-transitory memory coupled to the at least one processor and having program instructions stored thereon which, when executed by the at least one processor, cause the apparatus to:

obtain a first packet detection rule (PDR), wherein the first PDR is used to detect a multicast packet; and

send an N4 session identifier and the first PDR to a user plane function network element, the N4 session identifier corresponding to an N4 session, wherein the N4 session identifier and the first PDR enable the user plane function network element to configure the first PDR in the N4 session on the user plane function network element, and the first PDR indicates the user plane function network element to continue matching the multicast packet with another PDR after detection of the multicast packet.

12. The communication apparatus according to claim 11 , wherein the first PDR comprises a type indication, an indication to continue matching, packet duplication information, or packet duplication skip information, and the type indication, the indication to continue matching, the packet duplication information, or the packet duplication skip information indicates to continue matching another PDR.

13. The communication apparatus according to claim 11 , wherein the multicast packet is a broadcast packet, and the first PDR comprises a broadcast address; and the program instructions further cause the apparatus to:

determine a first N4 session that corresponds to a group and that is on the user plane function network element, wherein the broadcast packet belongs to the group, and the first N4 session is one of all N4 sessions that correspond to the group and that are on the user plane function network element, and wherein the N4 session identifier is an identifier of the first N4 session.

14. A communications apparatus, comprising:

at least one processor; and

a non-transitory memory coupled to the at least one processor and having program instructions stored thereon which, when executed by the at least one processor, cause the apparatus to:

receive a multicast packet, wherein the multicast packet comprises a multicast address;

match the multicast packet with one or more packet detection rules (PDRs) on the apparatus; and

continuing matching the multicast packet with a second PDR of the one or more PDRs when the multicast packet successfully matches a first PDR of the one or more PDRs, and the first PDR indicates to continue matching the multicast packet with another PDR.

15. The communication apparatus according to claim 14 , wherein the program instructions further cause the apparatus to:

when packet duplication skip information corresponding to the first PDR does not match sender information of the multicast packet, duplicate the multicast packet, and process a duplicated multicast packet according to a rule associated with the first PDR; or

when the packet duplication skip information corresponding to the first PDR matches the sender information of the multicast packet, skip processing the multicast packet according to a rule associated with the first PDR.

16. The communication apparatus according to claim 15 , wherein the multicast packet comprises the sender information of the multicast packet, and the sender information of the multicast packet comprises address information of a terminal device that sends the multicast packet.

17. The communication apparatus according to claim 15 , wherein the program instructions further cause the apparatus to:

receive the sender information of the multicast packet, wherein the sender information of the multicast packet comprises N19 indication information or N6 indication information.

18. The communication apparatus according to claim 17 , wherein the N6 indication information or the N19 indication information is comprised in general packet radio service (GPRS) tunneling protocol-user plane (GTP-U) tunnel header information.

19. The communication apparatus according to claim 14 , wherein the program instructions further cause the apparatus to:

determine an N4 session that matches the multicast packet and that is on the apparatus; and

match the multicast packet with each of PDRs in the N4 session in descending order of priorities of the PDRs.

20. The communication apparatus according to claim 14 , wherein the first PDR comprises a type indication, an indication to continue matching, packet duplication information, or packet duplication skip information, and the type indication, the indication to continue matching, the packet duplication information, or the packet duplication skip information indicates to continue matching another PDR.

21. The communication apparatus according to claim 14 , wherein the program instructions further cause the apparatus to:

receive an N4 session identifier and the first PDR from a session management function network element, wherein the first PDR is used to detect the multicast packet; and

configure the first PDR in a N4 session corresponding to the N4 session identifier.