Method for detecting multicast service flow and related apparatus

A second node comprising:

• a receiver configured to receive a first data packet encapsulated with an In-situ Flow Information Telemetry (IFIT) extension header from a first node that is a previous hop of the second node and is a head note in a multicast group, wherein the IFIT extension header comprises a first detection identifier identifying a multicast service flow to which the first data packet belongs;
• a processor coupled to the receiver and configured to copy, according to a quantity of third nodes that are next hops of the second node, the first data packet;
• and
• a transmitter coupled to the processor and configured to send the first data packet to each of the third nodes.

A computer program product comprising computer-executable instructions that are stored on a non-transitory computer-readable storage medium and that, when executed by a processor, cause a first node to:

• encapsulate an In-situ Flow Information Telemetry (IFIT) extension header into a data packet in the multicast service flow to obtain a second data packet, wherein the IFIT extension header comprises a first detection identifier identifying the multicast service flow;
• copy, according to a quantity of next-hop second nodes of the first node, the second data packet;
• and
• send the second data packet to each of the next-hop second nodes.