Analysis of Internet Multicast Traffic Performance Considering Multicast

Analysis of Internet Multicast Traffic Performance Considering Multicast Routing Protocol 2000 International Conference on Network Protocols, 2000. Author(s): Seiji Ueno、Toshihiko Kato、Kenji Suzuki 1

Outline • Introduction • Overview of DVMRP – Performance Analyzer • Overview of PIM-SM – Performance Analyzer • Conclusion • Reference 2

Introduction • Recently, audio and video delivery services are widely spread in the Internet. • In order to deliver these data to multiple receivers at the same time, the multicast technologies are indispensable. • Multicast traffic is controlled by its own routing protocol and the multicast routing protocol is more complex than conventional unicast routing protocols. 3

Overview of DVMRP • First multicast routing protocol ever deployed in the Internet. • Each router maintains a ‘multicast routing table’ by exchanging distance vector information among routers. – Constructs a source tree for each group using reverse path forwarding. • There is a “designated forwarder” in each subnet – Multiple routers on the same LAN select designated forwarder by lower metric or lower IP address (discover when exchanging metric info. ) • Once tree is created, it is used to forward messages from source to receivers. 4

Overview of DVMRP(cont. ) • DVMRP uses a Broadcast & Prune mechanism. • DVMRP router does not have any members of a particular multicast group and any dependent downstream routers about the multicast group, it sends a Prune message to the upstream router to ask for stopping the forwarding of multicast IP datagrams of the multicast group. 5

Overview of DVMRP(cont. ) • Advantage Relatively simple – Modest processing demands • Disadvantage – Convergence performance – Periodically flood multicast traffic to rebuild its trees – scalability – 6

Performance Analyzer 7

Overview of PIM-SM(cont. ) • Advantages – Less traffic • disadvantages – Bottle-neck at an RP router – Single point of failure 9

Performance Analyzer 10

Conclusion • DVMRP – It can estimate the reasons for starting and stopping multicast datagram transmissions, such as sender's starting transmission or the prune timeout. • PIM-SM – It can estimate the multicast traffic changes between RPT (Rendezvous Point Tree) and SPT (Shortest Path Tree). 11

Reference • RFC-1112 -Multicast • RFC-1075 -DVMRP • RFC-2362 -PIM-SM 12