Abstract: This application discloses a method, and a device for load balancing in a BIER network. The method includes: a network device obtains a BIER packet, and determines, based on an identifier in the BIER packet, a target next-hop node that reaches a destination address of the first BIER packet from a plurality of next-hop nodes of the network device. Then, the network device generates a target forwarding table based on the target next-hop node, and forwards the first BIER packet based on the target forwarding table. In this application, a control plane does not perform load balancing on a BIER packet in a manner of delivering a large quantity of load balancing tables to a forwarding plane, but the forwarding plane of the network device generates the target forwarding table to perform load balancing on the BIER packet.

Abstract: In a packet sending method, a first network device receives a first multicast packet, and determines first information based on the first multicast packet, where the first information indicates an attribute of the first multicast packet. The first network device determines that a state of a first link interface is unavailable, and performs a modulo operation on the first information based on a second parameter, to obtain second indication information, where the second indication information indicates a second link interface through which the first network device forwards the first multicast packet, the second parameter is a quantity of link interfaces whose states are available in a first load balancing group, and the first load balancing group includes the first link interface and the second link interface. The first network device forwards the first multicast packet through the second link interface.

Abstract: A packet processing method includes a first network device receiving a first Bit Index Explicit Replication (BIER) packet including a first BIER header. When the first BIER packet is a packet sent to a second network device, and in response to determining that the second network device is an edge node device in a BIER communication network and does not support BIER packet forwarding, the first network device determines a target label used for a reverse path forwarding (RPF) check, updates the first BIER packet to obtain a second BIER packet, where the second BIER packet includes the target label but does not include the first BIER header, and sends the second BIER packet to the second network device.

Abstract: A bit index explicit replication (BIER) forwarding entry construction method is provided. The method includes receiving, by a second network device, a first message sent by a first network device, where the first message includes a host routing prefix of the first network device, first BIER information, and second BIER information. The first BIER information includes a bit index forwarding table identifier (BIFT ID) of the first network device, the second BIER information includes a bit forwarding router identifier (BFR ID) of at least one bit forwarding router (BFR) in a first area. The second network device constructs a BIER forwarding entry based on the first BIER information, the second BIER information, and the host routing prefix.

Abstract: A reverse path forwarding (RPF) check method includes, after receiving a multicast data packet from a head node, a tail node may obtain a multicast source address, a multicast group address and encapsulation information that are carried in the multicast data packet. The tail node obtains, based on the multicast source address, the multicast group address, and a first correspondence, a first identifier identifying an upstream multicast hop (UMH) node corresponding to the multicast data packet. The tail node may further obtain, based on the encapsulation information of the multicast data packet and a second correspondence, a second identifier identifying the head node corresponding to the multicast data packet. After obtaining the first identifier and the second identifier, the tail node may perform an RPF check based on the first identifier and the second identifier.

Abstract: A packet sending method includes that a first network device receives a first packet from a customer edge (CE) device, where the first packet includes a first Internet Protocol (IP) version 6 (IPv6) header and a first payload, and the first IPv6 header includes a source address (SA) and a destination address (DA); determines, according to an entry, an address identifier corresponding to the SA and the DA, where the entry includes a correspondence between the SA and the DA and the address identifier; updates the first IPv6 header in the first packet to a second IPv6 header to obtain a second packet; encapsulates the second packet using the address identifier to obtain an encapsulated packet, the address identifier is located at an outer layer of the second packet; and sends the encapsulated packet to a second network device.

Abstract: An IPv6 packet processing method and apparatus where a first routing device obtains an IPv6 packet, and sends the IPv6 packet to a next-hop routing device. The IPv6 packet includes an IPv6 extension header that includes preceding general indication information, where the preceding general indication information includes first information, and where the first information is used to indicate to process the IPv6 packet only on a data plane of a routing device and not to send the IPv6 packet to a CPU.

Abstract: This application provides a method for sending a BIERv6 packet and a first network device. The method includes: determining, by a first network device, that an active next-hop device for reaching a second network device is faulty, where the first network device belongs to a first area in a BIER domain, the second network device and the active next-hop device belong to a second area in the BIER domain, the active next-hop device is a border device in the second area and is configured to connect to the first area, and the first area and the second area have different protocols; and sending, by the first network device, a BIERv6 packet to a backup next-hop device for reaching the second network device, where the backup next-hop device is a border device in the second area and is configured to connect to the first area.

Abstract: A destination node device starts a timer when the destination node device determines that a network topology changes; before the timer expires, the destination node device forwards the BIER packet by using an old forwarding table and establishes a new forwarding table, where the old forwarding table is a forwarding table used by the destination node device before the network topology changes, the new forwarding table is a forwarding table established by the destination node device based on the changed network topology; and after the timer expires, the destination node device switches the old forwarding table to the new forwarding table, and forwards the BIER packet according to the new forwarding table.

Abstract: This application provides a BIER packet sending method. The method includes: receiving a BIER packet that is encapsulated using an IPv6 protocol and that is sent by a second forwarding device, where the BIER packet includes an IPv6 basic header and a BIER header, a destination address field in the IPv6 basic header is a first IPv6 address of the first forwarding device; determining, based on an identifier corresponding to a first IPv6 address in a forwarding table, to perform BIER forwarding on the BIER packet, where the identifier is used to indicate that the first IPv6 address is a destination address for BIER forwarding. In the technical solution provided in this application, a node may determine, based on the identifier of the first IPv6 address, to perform BIER forwarding on the BIER packet.

Abstract: A multicast data packet processing method performed by an intermediate node of a multicast tree includes: receiving a first Bit Index Explicit Replication (BIER) packet including a first label; obtaining, according to the first label, a second label corresponding to a multicast tree including the intermediate node; and obtaining a second BIER packet according to the second label and the first BIER packet, and sending the second BIER packet which includes the second label.

Abstract: A multicast forwarding method applied to a BIER multicast network includes establishing, by a head node device, a first tunnel; generating a first entry; obtaining bit string information of a first multicast stream, where the bit string information includes an identifier of a tail node device that the first multicast stream is expected to reach; determining whether first bit string map information includes the identifier, in the bit string information, of the tail node device that the first multicast stream is expected to reach; and forwarding, by the head node device, the first multicast stream to a first intermediate node device through the first tunnel when the head node device determines that the first bit string map information includes the identifier in the bit string information, of the tail node device that the first multicast stream is expected to reach.

Abstract: A multicast data packet processing method in a point-to-multipoint (P2MP)-based bit index explicit replication (BIER) multicast tree, which includes an intermediate node configured to use P2MP to forward a BIER packet, includes receiving a first multicast data packet with a BIER header having a first label. The method further includes obtaining a first forwarding entry based on the first label. The first forwarding entry includes the first label, a first identifier identifying the multicast tree, and a second identifier instructing to perform P2MP forwarding. The method further includes obtaining, based on the first identifier, a second forwarding entry including the first identifier and a second label. The method further includes obtaining a second multicast data packet based on the second identifier, the second forwarding entry, and the first multicast data packet, and sending the second multicast data packet. The second multicast data packet includes the second label.

Abstract: A bit index explicit replication (BIER) packet sending method includes receiving, by a first node in a first BIER domain, a packet from a second node in a second BIER domain, where the packet carries an identifier of the second BIER domain, determining a BIER packet sending policy corresponding to the identifier of the second BIER domain based on the identifier of the second BIER domain and according to a preconfigured BIER packet sending policy, and encapsulating and sending a BIER packet according to the BIER packet sending policy.

Abstract: A BIERv6 packet forwarding method, device, and system. The method includes: receiving, by a first network device, a BIERv6 packet, where the first network device is a BFR or a BFER; determining, by the first network device, whether a value of a hop limit field in the BIERv6 packet is less than or equal to a preset threshold of the first network device, where the preset threshold is a value greater than or equal to 2, and is determined based on a quantity of one or more consecutive second network devices connected to the first network device, and the second network device is a device that does not support BIER forwarding; and when the value of the hop limit field in the BIERv6 packet is less than or equal to the preset threshold, avoiding, by the first network device, forwarding the BIERv6 packet.

Abstract: A packet detection method includes obtaining, by a first network device, a Bit Index Explicit Replication (BIER) packet, where the BIER packet includes trap information, and the trap information indicates whether the BIER packet is a valid BIER packet, determining, by the first network device, whether the trap information is valid, and determining, by the first network device, that the BIER packet is an invalid BIER packet when the first network device determines that the trap information is valid.

Abstract: A packet forwarding method. The method includes: a first node configures a first identifier of a first VPN and a first IPv6 address on a control plane. The first node sends a first indication message to a second node, where the first indication message carries the first identifier and the first IPv6 address. The second node first determines, based on locally configured information about the first VPN and the first identifier in the first indication message, a second identifier that is of the second node and that satisfies a preset correspondence with the first identifier, and then establishes a correspondence between the first IPv6 address and the second identifier. The first node encapsulates, on a forwarding plane based on the first IPv6 address, a multicast data packet belonging to the first VPN, to obtain a to-be-forwarded BIER packet and sends the to-be-forwarded BIER packet.

Abstract: The method includes: generating, by a first device, a first packet including a BIER header, where the BIER header includes entropy, and the entropy includes a first part and a second part; determining, by the first device based on the first packet, that there are a plurality of forwarding entries used to forward the first packet; selecting, by the first device, one forwarding entry from the plurality of forwarding entries based on the first part, where the selected forwarding entry includes an address of a second device, and the second device is a next-hop device of the first device; and sending, by the first device, the first packet to the second device, where the second part is used by the second device to select, from a plurality of forwarding entries used to forward the first packet, a forwarding entry used by the second device to forward the first packet.

Abstract: This application provides a multicast data packet processing method and a forwarding device. The method includes: establishing, by a first forwarding device, a segment routing header SRH-based tunnel with a third forwarding device, where the SRH-based tunnel passes through a second forwarding device that does not support bit index explicit replication BIER; generating, by the first forwarding device, a first multicast data packet based on a multicast data packet from a multicast source and the SRH-based tunnel, where the first multicast data packet includes a first packet header, a second packet header, and the multicast data packet from the multicast source, the first packet header includes an SRH header, and a destination address included in the second packet header is an address of the second forwarding device; and sending, by the first forwarding device, the first multicast data packet to the second forwarding device through the SRH-based tunnel.

Abstract: A multicast data packet processing method in a point-to-multipoint (P2MP)-based bit index explicit replication (BIER) multicast tree, which includes an intermediate node configured to use P2MP to forward a BIER packet, includes receiving a first multicast data packet with a BIER header having a first label. The method further includes obtaining a first forwarding entry based on the first label. The first forwarding entry includes the first label, a first identifier identifying the multicast tree, and a second identifier instructing to perform P2MP forwarding. The method further includes obtaining, based on the first identifier, a second forwarding entry including the first identifier and a second label. The method further includes obtaining a second multicast data packet based on the second identifier, the second forwarding entry, and the first multicast data packet, and sending the second multicast data packet. The second multicast data packet includes the second label.