Introduction to IP multicast routing
POSTECH Networking and Distributed Systems Lab. - 2 - ! "# $%& !'! % ()*$+,-./ 0001.&234+ ! 5 '!$"6!%)6 000$"6,%&"&& POSTECH Networking and Distributed Systems Lab. - 3 - % 5 5 POSTECH Networking and Distributed Systems Lab. - 4 - !+6 1. $ %" 7 # POSTECH Networking and Distributed Systems Lab. - 5 - #6 -+. (*3 ! "3 1.34+ " "" POSTECH Networking and Distributed Systems Lab. - 6 - 8 $ 5 - ! $ 5 - ! POSTECH Networking and Distributed Systems Lab. - 7 - 6 +69 85 :;<====== :;6 :; >9?6@ POSTECH Networking and Distributed Systems Lab. - 8 - A $%+ POSTECH Networking and Distributed Systems Lab. - 9 - 6>@ POSTECH Networking and Distributed Systems Lab. - 10 - *6 (. (.6 $+6 $6 (.6 $""+6 4 [...]... lo o d i i n g F i r s t F lo o d i n g F o u rth F lo o d iin g POSTECH Networking and Distributed Systems Lab - 24 - Distance-Vector Multicast Routing Protocol Intra-Domain Protocol of Dense Mode Construct source-based multicast tree Depends on RIP, the Unicast protocol Flood & Prune for construct tree by the first packet POSTECH Networking and Distributed Systems Lab - 25 - Constructing DVMRP... Exist at IP module of host IGMP messages Enables a MR to keep track of group Host membership query Host membership reply Join-group report Leave-group report POSTECH Networking and Distributed Systems Lab - 21 - Contents Intra Domain MR Protocol RPF DVMRP MOSPF CBT PIM-DB PIM-SM POSTECH Networking and Distributed Systems Lab - 22 - Reverse Path Forwarding A method to Find shortest... to Implement Incrementally deployable POSTECH Networking and Distributed Systems Lab - 18 - Classes of MR Protocols Host to Router Intra-Domain IGMP DVMRP, MOSPF, PIM-DM/SM, MIP Inter-Domain YAM, QosMIC, BGMP, PTMR-, EXPRESS POSTECH Networking and Distributed Systems Lab - 19 - Example of MR protocols POSTECH Networking and Distributed Systems Lab - 20 - Internet Group Management Protocol... Group shared multicast tree STP is a NP-complete problem Steiner node A MR tree nodes which do not belongs to multicast group(e.g.:node D, E in fig) POSTECH Networking and Distributed Systems Lab - 16 - Two Steiner Trees A ll R o u te POSTECH Networking and Distributed Systems Lab 1 s t S te in e r T r e e R o u te 2 n d S te in e r T re e R o u te - 17 - Properties of Good MR Protocols Efficiency... packet delivery costs No routing loops Support incremental deployment Use DVMRP Tunnel for inter domain Easy to implement Low computational complexity POSTECH Networking and Distributed Systems Lab - 28 - Drawbacks of DVMRP Big memory usage Poor scalability Waste bandwidth Hard to Mange Group(flooding) POSTECH Networking and Distributed Systems Lab - 29 - Multicast Open Shortest Path... to Mange Group(flooding) POSTECH Networking and Distributed Systems Lab - 29 - Multicast Open Shortest Path First Intra-Domain Protocol of Dense Mode Depends on OSPF, Unicast Protocol Tree is built on demand by First Packet Every routers knows complete routing topology Make Source-based Tree Dijkstra Algorithm for computing Paths POSTECH Networking and Distributed Systems Lab - 30 - Constructing... MOSPF CBT PIM-DB PIM-SM POSTECH Networking and Distributed Systems Lab - 22 - Reverse Path Forwarding A method to Find shortest path from one source to many receivers flood & prune Uses unicast routing table Employed in many MR protocol DVMRP, MOSPF, PIM-DM, etc POSTECH Networking and Distributed Systems Lab - 23 - Steps of RPF MR3 MR2 MR1 MR6 MR4 MR5 MR7 MR8 MR9 A ll R o u te S e... computation Poor Scalability Not support incremental deployment No tunnels nor any feature for support it Hard to Mange Group(flooding) POSTECH Networking and Distributed Systems Lab - 34 - Core Based Trees Intra-Domain Protocol of Sparse Mode Uses only one tree per group To Overcome the scalability Do not use RPF POSTECH Networking and Distributed Systems Lab - 35 - Joining a CBT Group... Heavy control message Hard to manage group Dense mode DVMRP,MOSPF, PIM-DM POSTECH Networking and Distributed Systems Lab - 12 - Source Based Tree A ll R o u te POSTECH Networking and Distributed Systems Lab M u ltic a s tin g T re e R o u te - 13 - Group Shared Tree A Tree Required per Group Center based Tree Constructing Scalable Light control message Easy to Manage group Traffic Concentration