Cisco Cisco IOS Software Release 12.0(15)S

J - Join SPT

For (*, G) entries, indicates that the rate of traffic flowing down the 
shared tree is exceeding the SPT-Threshold set for the group. (The 
default SPT-Threshold setting is 0 kbps.) When the J- Join shortest 
path tree (SPT) flag is set, the next (S, G) packet received down the 
shared tree triggers an (S, G) join in the direction of the source, 
thereby causing the router to join the source tree.

For (S, G) entries, indicates that the entry was created because the 
SPT-Threshold for the group was exceeded. When the J- Join SPT 
flag is set for (S, G) entries, the router monitors the traffic rate on the 
source tree and attempts to switch back to the shared tree for this 
source if the traffic rate on the source tree falls below the 
SPT-Threshold of the group for more than 1 minute.

The router measures the traffic rate on the shared tree and 
compares the measured rate to the SPT- Threshold of the 
group once every second. If the traffic rate exceeds the 
SPT-Threshold, the J- Join SPT flag is set on the (*, G) entry 
until the next measurement of the traffic rate. The flag is 
cleared when the next packet arrives on the shared tree and a 
new measurement interval is started.

If the default SPT-Threshold value of 0 kbps is used for the 
group, the J- Join SPT flag is always set on (*, G) entries and 
is never cleared. When the default SPT-Threshold value is 
used, the router immediately switches to the shortest-path 
tree when traffic from a new source is received.

M - MSDP created entry

Indicates that a (*, G) entry was learned through a Multicast Source 
Discovery Protocol (MSDP) peer. This flag is only applicable for a 
rendezvous point (RP) running MSDP.

X - Proxy Join Timer 
Running

Indicates that the proxy join timer is running. This flag is only set for 
(S, G) entries of an RP or “turnaround” router. A “turnaround” router 
is located at the intersection of a shared path (*, G) tree and the 
shortest path from the source to the RP.

A - Advertised via MSDP Indicates that an (S, G) entry was advertised through an MSDP peer. 

This flag is only applicable for an RP running MSDP.

U  -  URD

Indicates that a URD channel subscription report was received for the 
(S, G) entry.

I - Received Source 
Specific Host Report

Indicates that an (S, G) entry was created by an (S, G) report. This (S, 
G) report could have been created by IGMPv3, URD, or IGMP v3lite. 
This flag is only set on the designated router (DR).

Outgoing interface flags:

Provides information about the entry.

H - Hardware switched

Indicates that a Multicast Multilayer Switching (MMLS) forwarding 
path has been established for this entry.