The mstat feature adds the capability to show the multicast path in a limited graphic display and indicates drops, duplicates, TTLs, and delays at each node. This information is useful to the network operator because it identifies nodes with high drop and duplicate counts. Duplicate counts are shown as negative drops.
The output of mstat provides a limited pictorial view of the path in the forward direction with data flow indicated by arrows pointing downward and the query path indicated by arrows pointing upward. For each hop, both the entry and exit addresses of the router are shown if different, along with the initial TTL required on the packet in order to be forwarded at this hop and the propagation delay across the hop assuming that the routers at both ends have synchronized clocks. The output consists of two columns, one for the overall multicast packet rate that does not contain lost/sent packets and the other for the (S,G)-specific case. The (S,G) statistics also do not contain lost/sent packets.