Abstract: In accordance with an embodiment, a packet transmission method includes receiving, by a second provider edge (PE) through a multicast tunnel, a bit indexed explicit replication (BIER) packet sent by a first PE, wherein the BIER packet comprises a bit string, and the bit string indicates a customer edge (CE) designated to receive the BIER packet; and processing, by the second PE based on the bit string, the BIER packet.

Abstract: A first network device receives a BIER packet sent by a second network device, where the BIER packet includes an IPv6 header, a BIER header, and a multicast packet, a destination address of the IPv6 header or a first field of the BIER header carries a service identifier, and the service identifier identifies a virtual private network VPN instance. The first network device determines a VRF table based on the service identifier and a first correspondence, where the first correspondence includes a correspondence between the service identifier and the VRF table. The first network device sends the multicast packet to a first CE device in the VRF table based on the VRF table.

Abstract: Embodiments of this application provide a performance measurement method and apparatus, and a system. In the method, a bit forwarding ingress router BFIR obtains a first packet, where the first packet includes an identifier of the BFIR, a bit string, and a first parameter that is used for performance measurement, the bit string is used to identify one or more bit forwarding egress routers BFERs, and the first packet is not used to transmit multicast data; and the BFIR sends the first packet to the one or more BFERs based on the bit string included in the first packet.

Abstract: Embodiments of this application provide a next hop determining method. The method is applied to a BIER domain based on bit index forwarding routing, and includes: A third device obtains first BIER information of a first device, an attribute of the first device, second BIER information of a second device, and an attribute of the second device, where the first BIER information includes a bit forwarding router identifier BFR-id of an edge bit forwarding router BFR in a sub-domain, and the second BIER information includes the BFR-id of the edge BFR in the sub-domain. The third device determines, based on the first BIER information, the second BIER information, the attribute of the first device, and the attribute of the second device, a next hop to the edge BFR in the sub-domain.

Abstract: A packet header information obtaining method. The method includes: obtaining, by a communications device, a first packet, where the first packet includes a plurality of extension packet headers; and obtaining an extension header self-describing option from the first packet, where the extension header self-describing option is used to indicate information about the plurality of extension packet headers. Therefore, the communications device obtains, based on the extension header self-describing option in the first packet, a first extension packet header included in the plurality of extension packet headers. Packet header information of the extension packet header in the first packet can be obtained by using the extension header self-describing option, and the first extension packet header that needs to be parsed can be directly located from the first packet by using the obtained packet header information.

Abstract: A method for sending a multicast packet provided in embodiments of this application includes: a first network device obtains a first multicast packet, where the first multicast packet includes a bit string bit string and an identifier of a network slice, the bit string corresponds to a second network device, and the network slice corresponds to a multicast service of the second network device. The first network device obtains, based on the bit string and the identifier of the network slice, a first interface corresponding to the network slice. The first network device sends the first multicast packet to the second network device by using the first interface.

Abstract: An IPv6 packet sending method, a device, and a system is provided. The method includes a first network device receives a first IPv6 packet, where the first IPv6 packet includes a packet header and an inner packet, and the packet header includes a hop limit field. The network device further determines whether a value of the hop limit field is less than or equal to a preset threshold, determines whether the inner packet is a multicast packet, and avoids forwarding the first IPv6 packet when the value of the hop limit field is less than or equal to the preset threshold and the inner packet is the multicast packet.

Abstract: This application provides a packet forwarding method, device, and system. The method includes: A first network device obtains a first packet, where the first packet includes a multicast packet; the first network device determines a next-hop destination address DA of the multicast packet based on a source address SA and a first correspondence relationship, where the SA is used to identify a multicast path corresponding to the multicast packet, and the first correspondence relationship includes the SA and a next-hop DA of the first network device on the multicast path; the first network device obtains a second packet based on the next-hop DA, where the second packet is a unicast packet obtained after IPv6 encapsulation is performed on the multicast packet; and the first network device forwards the second packet along the multicast path based on the next-hop DA.

Abstract: A bit index explicit replication (BIER) operations, administration, and maintenance (OAM) detection method includes a bit forwarding ingress router (BFIR) obtaining a detection request packet based on a first BIER OAM packet, and sending the detection request packet to at least one bit forwarding egress router BFER. The detection request packet includes a first packet and a first packet header. The first packet is a packet obtained by encapsulating the first BIER OAM packet. The first packet header includes a bit string, and the bit string indicates the at least one bit forwarding egress router BFER that is to be measured.

Abstract: This application provides a P2MP tree connectivity detection method, a device, and a system. The method is applied to SR domain. The SR domain includes a P2MP tree. The P2MP tree includes a first node. The first node is a root node or an intermediate replication node of the P2MP tree. The method includes: The first node determines a first next-hop node of the first node based on replication branch information; and the first node sends a first request message to the first next-hop node. The first request message includes a segment identifier SID of the first next-hop node. The first request message includes a first identifier. The first identifier indicates that the first request message is for connectivity detection.

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: This application provides a packet verification method, and the method includes: A first network device receives a BIER packet, where packet header information of the BIER packet includes a first keyed-hash message authentication code HMAC, and the first HMAC is used to verify whether the BIER packet is a valid BIER packet; determines a second HMAC based on a first key and first information in the packet header information, where the first information is used to indicate forwarding information of the BIER packet; determines whether the first HMAC is the same as the second HMAC; and when determining that the first HMAC is different from the second HMAC, determines that the BIER packet is an invalid 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 BIER multicast traffic statistics collection method, a device, and a system. The method includes: A first network device obtains a first BIER packet. The first network device performs traffic statistics collection on the first BIER packet based on multicast flow information, to obtain a traffic statistics collection result of the first BIER packet, where the multicast flow information is used to identify a multicast flow to which the first BIER packet belongs. The first network device sends the multicast flow information and the traffic statistics collection result of the first BIER packet to a controller.

Abstract: This application provides a method and an apparatus for sending a multicast packet. In the method, an ingress device obtains a region identifier of a region corresponding to a received multicast packet. The ingress device obtains, based on the region identifier and a forwarding entry, an address of an intermediate device that is used to forward the multicast packet to the region. The forwarding entry includes the region identifier and the address of the intermediate device. The ingress device sends the multicast packet based on the address of the intermediate device. An intermediate device obtains, based on a multicast packet from an ingress device, a region identifier of a region corresponding to the multicast packet. The intermediate device obtains an address of a next-hop device based on the region identifier and a forwarding entry. The intermediate device sends the multicast packet based on the address of the next-hop device.

Abstract: This application relates to the field of communication technologies, and discloses a method and an apparatus for determining a link for forwarding a service flow, and a storage medium. In embodiments of this application, a first forwarding device may obtain identification information of a first service flow; and determine, based on the identification information of the first service flow, a link bandwidth matrix, and link statuses respectively corresponding to N links, a first link for forwarding the first service flow. It can be learned that in embodiments of this application, a hash operation does not need to be performed based on a device identifier of each forwarding device, and a specific forwarding device that performs forwarding does not need to be determined by comparing a plurality of hash values. Therefore, an amount of calculation is small and efficiency is high.

Abstract: This application provides a packet sending method. The method includes: receiving, by a first network device, a data packet, and encapsulating the data packet to obtain a first packet, where the first packet includes an IPv6 header, a bit index explicit replication BIER header, and the data packet, and some bits of a source IPv6 address field in the IPv6 header include identification information of a first tenant; and sending, by the first network device, the first packet to a second network device, where the identification information of the first tenant is used by the second network device to determine to send the data packet to an interface, corresponding to the first tenant, of the second network device.

Abstract: A method includes that a first routing device obtains a first identifier and a second identifier that are advertised by the second routing device. The first identifier is a bit forwarding router (BFR)-identifier (ID) of the second routing device that is valid in a bit indexed explicit replication (BIER) sub-domain to which the second routing device belongs. The second identifier is used to indicate being used only as a bit forwarding ingress router (BFIR). The first routing device skips, based on the first identifier and the second identifier, setting a bit that is in a forwarding bit mask (F-BM) and that corresponds to the first identifier. The F-BM is included in all BIER forwarding entries corresponding to the BIER sub-domain on the first routing device.

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

Abstract: A packet forwarding method includes that a first network device receives a multicast packet from a multicast source device and forwarded by a device group, where the device group includes a second network device and a third network device, and the multicast packet is forwarded to the first network device by one network device in the device group. The first network device determines, according to a reverse-path forwarding (RPF) entry, that the multicast packet is forwarded by the device group, where the RPF entry includes a first sub-entry instructing the first network device to forward the multicast packet sent by the second network device and a second sub-entry instructing the first network device to forward the multicast packet sent by the third network device. The first network device sends the multicast packet to a multicast destination device according to the RPF entry.