Objectives
The simulator ticks each one as soon as the network meets it.
On each router add the system interface and every router interface to pim (configure router "Base" pim interface …).
Configure pim rp ipv4 static address 2.2.2.2 with group-prefix 224.0.0.0/4 on every router.
On R3 add interface "if2" (PC3’s LAN) to igmp, and commit on every router.
Join 239.1.1.1 on PC3, then ping 239.1.1.1 from SRC: PC3 replies.
On R3, show router pim group lists (*,G) and an spt (S,G) for 239.1.1.1.
Before you start
SR OS runs PIM sparse mode and SSM; there is no dense mode. Changes stay in the candidate until commit. IGMPv3 is the default version on SR OS.
Concept
PIM sparse mode (ASM): shared tree, register, SPT
Sparse mode sends a stream only where it is requested. Receivers’ routers join a shared tree rooted at a rendezvous point (RP); the source’s router registers the stream to the RP; once the stream arrives, the receiver’s router joins the source directly on the shortest-path tree (SPT).
Concept
IGMP: how a receiver asks for a group
A multicast group (224.0.0.0/4) is an address many receivers can listen to at once. A host tells its local router it wants a group with an IGMP membership report; the router then pulls the stream toward that LAN. IGMPv2 can only name the group; IGMPv3 can also name the source.
