35
CONFIDENTIAL
26-Jan-04
© 2002 Procket Networks, Inc. All rights reserved.
PIM-SM Operation
Designated Router (DR)
•Neighboring PIM-SM routers multicast periodic “Hello” messages to each other - default 30 secs.
•Hello-interval tunable for faster convergence
•On receipt of a Hello message
• a router stores the IP address and priority for that neighbor
•Router with highest IP address is selected as the DR, if the priorities match
•When DR goes down:
•new one selected by scanning all neighbors on the interface and choosing the one with the highest IP address
•DR sends
•“Join/Prune” messages toward the RP from receiver network
•“Register” messages toward the RP from source network
•