Abstract: A communication method includes a first network device obtaining a first route and a second route from a second network device. A first network segment corresponding to the first route is a subnet segment of a second network segment corresponding to the second route. The second route is an aggregated route, and the first route indicates that the first network segment is unreachable. The first network device switches a next hop of the aggregated route based on the first route.

Abstract: The technology of this application relates to an information processing method, apparatus, and system. The method includes a controller determining network slice information corresponding to a first network device. The controller sends a border gateway protocol (BGP) packet to the first network device, where the BGP packet includes the network slice information, and the network slice information is used by the first network device to configure a network slice. According to the technical solution provided in this application, efficiency of delivering network slice information can be improved.

Abstract: This application discloses a transmission path fault processing method and apparatus, and a system, to resolve a problem that a packet fails to be forwarded because a previous-hop node of a faulty node cannot process a stitching label. The method includes: receiving, by a first network device, a stitching label and a stitching label stack list corresponding to the stitching label that are sent by a stitching network device; determining, in a process of sending a packet through a primary path, that the stitching network device is faulty, where the packet includes a label stack list, and the stitching network device is a next-hop network device of the first network device; and replacing, by the first network device, the stitching label in the label stack list with the stitching label stack list, and switching, based on the updated label stack list, the packet to a backup path for sending.

Abstract: This application provides a packet processing method and apparatus, a device, and a storage medium, and pertains to the field of communication technologies. In this application, a control identifier field is added to a packet, and the control identifier field indicates whether forwarding of the packet is allowed when the first network device does not configure the slice identifier on an outbound interface. The control identifier field and a slice identifier of a network slice are carried in the packet, so that the slice identifier and the control identifier field are transmitted on a network together. When a receive end does not configure the slice identifier on the outbound interface, the receive end can discard the packet based on the control identifier field, instead of forwarding the packet by using routing information.

Abstract: A path calculation method, apparatus, and device, to implement network slicing. The path calculation method includes: obtaining an algorithm constraint supported by each of a plurality of network devices, where the algorithm constraint is a constraint of a forwarding path algorithm, and the forwarding path algorithm is used to calculate, for the network device, a forwarding path that meets the algorithm constraint; performing network topology division on the plurality of network devices, where network devices in a same network topology support a same algorithm constraint; and calculating a forwarding path between network devices in each network topology based on the algorithm constraint, of the forwarding path algorithm, corresponding to the network topology.

Abstract: This application discloses a communication method and a related apparatus, and relates to the field of communication technologies. The method is applied to an SD-WAN overlay network. A CPE autonomously generates an SD-WAN overlay routing table, so that communication reliability and flexibility are improved. An RR specifies an overlay multicast RPF route to the CPE to implement SD-WAN overlay multicast communication, and the CPE does not need to perform path computation autonomously, so that a computing power requirement of the CPE is reduced. An identifier of the CPE and an identifier of a site are carried in a multicast join message to implement the SD-WAN overlay multicast communication. A standard IP header is carried in a multicast service packet to implement the SD-WAN overlay multicast communication, so that generalization, applicability, and compatibility are improved.

Abstract: A packet forwarding method implemented by a head node, includes receiving a first packet and a second packet, where the first packet is a packet forwarded by using a first network slice, and the second packet is a packet forwarded by using a second network slice; in response to the first packet matching a first segment routing policy, generating a third packet based on the first packet, where the third packet carries slice information of the first network slice and a first SID list; in response to the second packet matching the first segment routing policy, generating a fourth packet based on the second packet, where the fourth packet carries slice information of the second network slice and the first SID list; and forwarding the third packet and the fourth packet.

Abstract: A communication method includes a first network device obtaining a first route and a second route from a second network device. A first network segment corresponding to the first route is a subnet segment of a second network segment corresponding to the second route. The second route is an aggregated route, and the first route indicates that the first network segment is unreachable. The first network device switches a next hop of the aggregated route based on the first route.

Abstract: This application discloses a transmission path fault processing method and apparatus, and a system, to resolve a problem that a packet fails to be forwarded because a previous-hop node of a faulty node cannot process a stitching label. The method includes: receiving, by a first network device, a stitching label and a stitching label stack list corresponding to the stitching label that are sent by a stitching network device; determining, in a process of sending a packet through a primary path, that the stitching network device is faulty, where the packet includes a label stack list, and the stitching network device is a next-hop network device of the first network device; and replacing, by the first network device, the stitching label in the label stack list with the stitching label stack list, and switching, based on the updated label stack list, the packet to a backup path for sending.

Abstract: A method for packet transmission in a network includes receiving, by a first node, a second segment identifier sent by the third node, receiving, by the first node, a packet sent by the second node through the first path, determining, by the first node, that a next-hop node of the first node on the first path is faulty, and in response to the determining, by the first node, that a next-hop node of the first node on the first path is faulty, adding, by the first node, the second segment identifier to the packet, and sending the packet to the third node through a second path, where the second path is established by the first node based on the second segment identifier.

Abstract: A packet sending method and device. The first node sets a next-hop of the routing information to a next-hop through which the first node reaches the first route source. The destination address of the routing information is the address prefix. When the second route source is superior to the first route source, the first node switches the next-hop of the routing information to a next-hop through which the first node reaches the second route source. Then, the first node adds, to a target packet, path information of a forwarding path from the first node to the second route source according to the switching operation, where a destination address of the target packet matches the address prefix. Finally, the first node forwards the target packet to the second route source through the forwarding path.

Abstract: This application provides a packet processing method and a device. In this application, a control identifier field is added to a packet, and the control identifier field indicates whether forwarding of the packet is allowed when a resource corresponding to a slice identifier fails to be matched. The control identifier field and a slice identifier of a network slice are carried in the packet, so that the slice identifier and the control identifier field are transmitted on a network together. When a receive end fails to match the resource corresponding to the slice identifier, the receive end can discard the packet based on the control identifier field, instead of forwarding the packet by using routing information.

Abstract: A user group-based packet forwarding method and a device are provided. The method includes: a first network device receives a first service packet sent by first user equipment, where the first service packet includes information about the first user equipment; the first network device determines whether the first network device includes a first user group corresponding to the information about the first user equipment; and the first network device determines, based on a determining result, a value of first group information, generates a first segment routing over internet protocol version 6 (SRv6) packet, and sends the first SRv6 packet to a second network device, where the first SRv6 packet includes the first group information and the first service packet, and the first group information indicates an interworking policy that is determined based on the first user group.

Abstract: A packet transmission method includes: A first network device receives a first data packet; and the first network device updates the first data packet to obtain a second data packet, where the second data packet includes a global identifier; the first network device sends the second data packet to a second network device, where the global identifier is used by the second network device to verify the second data packet based on a correspondence, and the correspondence is a correspondence between the global identifier and an egress port through which the second network device transmits the second data packet.

Abstract: This application discloses a packet processing method and a related apparatus, applied to a network slice. The method includes: A first network device obtains a first packet, where the first packet includes a first slice identifier, the first slice identifier includes a plurality of consecutive sub-identifiers, the plurality of sub-identifiers indicate different attributes of a first network slice, and the first slice identifier identifies the first network slice to which the first packet belongs. The first network device forwards the first packet based on the first slice identifier. In this solution, a slice identifier including a plurality of sub-identifiers is carried in a packet. Different sub-identifiers indicate different attributes of a network slice.

Abstract: This application provides a packet forwarding method, apparatus, and system, and belongs to the field of communication technologies. In a scheme provided in this application, a packet includes both a destination address and a behavior instruction, and at least two nodes in a packet forwarding system may identify the behavior instruction in the packet, and may forward the packet based on a first forwarding behavior indicated by the behavior instruction. Therefore, when a plurality of nodes in the packet forwarding system each need to perform a forwarding behavior on the packet, an SID does not need to be allocated to each node, but only the behavior instruction needs to be carried in the packet.

Abstract: A packet transmission method, a transmission control method, an apparatus, and a system are disclosed. A SR path includes a first network node and a second network node. There are a plurality of communication links between the first network node and the second network node. After obtaining a first packet, the first network node determines a first communication link based on a first link quality identifier carried in the first packet, and forwards the first packet to the second network node through the first communication link. The first link quality identifier indicates a first quality requirement on the communication link between the first network node and the second network node. The plurality of communication links between the first network node and the second network node include the first communication link, and link quality of the first communication link meets the first quality requirement.

Abstract: An information flooding method and a device, to flexibly manage flooding information of an interior gateway protocol (IGP) instance, adapt to flooding requirements in different scenarios, improve flooding efficiency, save network resources, and improve flooding information processing efficiency. The method includes: a first network device obtains a flooding information set, where the flooding information set includes flooding information corresponding to each of a plurality of flooding instances, and the plurality of flooding instances belong to one IGP instance. The first network device sends a plurality of packets, where each of the plurality of packets carries a corresponding flooding instance identifier and corresponding flooding information, and the flooding instance identifier is used to identify a flooding instance.

Abstract: This application discloses a method, an apparatus, and a system for processing a transmission path fault. In this application, after a first network device receives a packet, and when the first network device determines that a third network device is faulty, a difference between an initial value of a segment routing global block SRGB of the first network device and an initial value of an SRGB of the third network device is determined, and a backup path is determined based on the difference and a backup forwarding table. The first network device sends a first packet based on the backup forwarding table.