Provided are an information exchange method and apparatus, a tunnel establishment method and apparatus, a communication node and a storage medium. The method includes: receiving segment routing Internet Protocol version 6 (SRv6) path segment compression information reported by a second communication node, where the SRv6 path segment compression information includes node construction information and node behavior information of an SRv6 path segment identifier; and sending SRv6 path segment compression configuration information to a third communication node according to the SRv6 path segment compression information.

A method for establishing a segment routing (SR) tunnel based on an Internet Protocol version 6 (IPv6) data plane using a Path Computation Element Communication Protocol (PCEP) includes generating, by a path computation element (PCE), a first PCEP message, wherein the first PCEP message comprises indicating information and segment identifier (SID), and wherein the indicating information indicates that the SID is an IPv6 prefix of a node in a tunnel; receiving, by a first path computation client (PCC), the first PCEP message from the PCE; and establishing, by the first PCC, a Segment Routing over IPv6 (SRv6) tunnel from the first PCC to a second PCC.

A method includes: receiving an uplink data stream packet; determining a resource module used to process the uplink data stream packet and an identifier of the resource module; modifying the uplink data stream packet based on the identifier of the resource module; and forwarding a modified uplink data stream packet. After a downlink data stream packet is received, a resource module used to process the downlink data stream packet is determined based on an identifier of a resource module in the downlink data stream packet, where the identifier of the resource module in the downlink data stream packet is added after learning the identifier of the resource module in the uplink data stream packet. In this method, the uplink and downlink data stream packets are transmitted by using a same resource module, so that a success rate of communication transmission is effectively improved.

A route determining method, apparatus, and a network device are disclosed. The method includes a first forwarding node receives routing information from a second forwarding node, and then sends a packet to a destination node based on the routing information. The routing information includes a node identifier of the destination node and at least one piece of indication information that is in a one-to-one correspondence with at least one third forwarding node, and the second forwarding node belongs to the at least one third forwarding node. The packet includes the at least one piece of indication information, and the at least one piece of indication information indicates to forward the packet along the at least one third forwarding node.

A method for preventing a replay attack on a Segment Routing over Internet Protocol version 6 (SRv6) keyed hashed message authentication code (HMAC) verification. The method includes a network device receiving an SRv6 packet comprising anti-replay attack verification information. The network device performs anti-replay attack verification based on the anti-replay attack verification information. The network device performs HMAC hash computation on the SRv6 packet in response to the first SRv6 packet passing passes the anti-replay attack verification.

A data transmission method, a node, and a system, the method including receiving, by a forwarding node, a data packet, where a label stack of the data packet comprises a path identifier (path-ID), where the path-ID is an identifier of a constrained path, and where the constrained path is a path that consists of at least two nodes arranged in a specific order, determining, by the forwarding node, that the forwarding node is a node on the constrained path, selecting, by the forwarding node, a target label/target address from a local available label block/address block according to the path-ID and according to a preset rule, where the label block/address block comprises at least one label/address, searching for, by the forwarding node, a corresponding target interface according to the target label/target address, and forwarding, by the forwarding node, the data packet through the target interface.

A connection status detection method used for detecting connectivity of a segment routing (SR) path between nodes is disclosed. After receiving a path detection packet, a first node responds to the path detection packet based on connectivity of an SR path between the first node and a third node, and the path detection packet is used to indicate to detect the connectivity of the segment routing (SR) path between the nodes.

A service execution method and apparatus, a system, and a storage medium related to the communications field are provided. The method includes: a first network device generates a first packet, where the first packet includes a segment routing header (SRH), the SRH includes a service identifier, and the service identifier is related to first service information and second service information. The first network device sends the first packet to a second network device, wherein the service identifier indicates the second network device to execute at least one service based on the first service information, the second service information, and the first packet. According to this application, a problem that a network service cannot be provided for an actual service packet in an SRv6 network can be resolved.

Various example embodiments for supporting source routing are presented herein. Various example embodiments for supporting source routing may be configured to support source route compression for source routing. Various example for supporting source route compression for source routing may be configured to support communication of a source routed packet over a path from an ingress node to an egress node over a network, wherein the network includes a set of network elements having a respective set of network element identifiers sharing a common prefix, wherein the source routed packet has encoded therein a source route block including the common prefix and an offset list, wherein the offset list includes a set of offset values associated with respective ones of the network elements of the path and configured to be combined with the common prefix to recover the network element identifiers of the respective ones of the network elements of the path.

Various example embodiments for supporting source routing are presented herein. Various example embodiments for supporting source routing may be configured to support source route compression for source routing. Various example for supporting source route compression for source routing may be configured to support source route compression for source routing based on use of shadow addresses. Various example for supporting source route compression for source routing based on use of shadow addresses may be configured to support source routing of packets based on use of shadow addresses of hops in place of actual addresses of hops to encode source routes within source routed packets, thereby compressing the source routes within the source routed packets and, thus, providing source route compression.