A per-hop postcard technique is disclosed. The per-hop postcard technique is implemented to improve Postcard-based Telemetry (PBT). A per-section postcard technique is also disclosed. The per-section postcard technique is implemented to improve In-situ OAM (IOAM). By utilizing these techniques, suitable on-path telemetry may be obtained for multicast traffic. In addition, these techniques may be used to reconstruct and visualize a multicast tree, to conduct performance monitoring, and to perform trouble shooting.