【正文】 Systems, Inc. 2214 1197_05_2022_c2 PIMDM Flood amp。 Prune Results After Pruning Source Receiver Multicast Packets Flood amp。 Prune process repeats every 3 minutes!!! (S, G) State still exists in every router in the work! 72 169。 2022, Cisco Systems, Inc. 2214 1197_05_2022_c2 PIMDM Assert Mechanism E0 Ining Multicast Packet (Successful RPF Check) E0 S0 Routers receive packet on an interface in their ―oilist‖!! – Only one router should continue sending to avoid duplicate packets. 1 S0 1 2 Routers send ―PIM Assert‖ messages Assert distance, metric Assert distance, metric 2 2 – Compare distance and metric values – Router with best route to source wins – If metric amp。 distance equal, highest IP adr wins – Losing router stops sending (prunes interface) 73 169。 2022, Cisco Systems, Inc. 2214 1197_05_2022_c2 PIMDM — Evaluation ? Most effective for small pilot works ? Advantages: – Easy to configure—two mands – Simple flood and prune mechanism ? Potential issues... – Inefficient flood and prune behavior – Complex Assert mechanism – Mixed control and data planes ?Results in (S, G) state in every router in the work ?Can result in nondeterministic topological behaviors – No support for shared trees 74 169。 2022, Cisco Systems, Inc. 2214 1197_05_2022_c2 PIMSM (RFC 2362) ? Supports both source and shared trees – Assumes no hosts want multicast traffic unless they specifically ask for it ? Uses a Rendezvous Point (RP) – Senders and Receivers ―rendezvous‖ at this point to learn of each others existence. ?Senders are ―registered‖ with RP by their firsthop router. ?Receivers are ―joined‖ to the Shared Tree (rooted at the RP) by their local Designated Router (DR). ? Appropriate for… – Wide scale deployment for both densely and sparsely populated groups in the enterprise – Optimal choice for all production works regardless of size and membership density. 75 169。 2022, Cisco Systems, Inc. 2214 1197_05_2022_c2 PIMSM Shared Tree Join Receiver RP (*, G) Join Shared Tree (*, G) State created only along the Shared Tree. 76 169。 2022, Cisco Systems, Inc. 2214 1197_05_2022_c2 PIMSM Sender Registration Receiver RP (S, G) Join Source Shared Tree (S, G) Register (unicast) Source Tree (S, G) State created only along the Source Tree. Traffic Flow 77 169。 2022, Cisco Systems, Inc. 2214 1197_05_2022_c2 PIMSM Sender Registration Receiver RP Source Shared Tree Source Tree RP sends a RegisterStop back to the firsthop router to stop the Register process. (S, G) RegisterStop (unicast) Traffic Flow (S, G) Register (unicast) (S, G) traffic begins arriving at the RP via the Source tree. 78 169。 2022, Cisco Systems, Inc. 2214 1197_05_2022_c2 PIMSM Sender Registration Receiver RP Source Shared Tree Source Tree Traffic Flow Source traffic flows natively along SPT to RP. From RP, traffic flows down the Shared Tree to Receivers. 79 169。 2022, Cisco Systems, Inc. 2214 1197_05_2022_c2 PIMSM SPT Switchover Receiver RP (S, G) Join Source Source Tree Shared Tree Lasthop router joins the Source Tree. Additional (S, G) State is created along new part of the Source Tree. Traffic Flow 80 169。 2022, Cisco Systems, Inc. 2214 1197_05_2022_c2 PIMSM SPT Switchover Receiver RP Source Source Tree Shared Tree (S, G)RPbit Prune Traffic begins flowing down the new branch of the Source Tree. Additional (S, G) State is created along along the Shared Tree to prune off (S, G) traffic. Traffic Flow 81 169。 2022, Cisco Systems, Inc. 2214 1197_05_2022_c2 PIMSM SPT Switchover Receiver RP Source Source Tree Shared Tree (S, G) Traffic flow is now pruned off of the Shared Tree and is flowing to the Receiver via the Source Tree. Traffic Flow 82 169。 2022, Cisco Systems, Inc. 2214 1197_05_2022_c2 PIMSM SPT Switchover Receiver RP Source Source Tree Shared Tree (S, G) traffic flow is no longer needed by the RP so it Prunes the flow of (S, G) traffic. Traffic Flow (S, G) Prune 83 169。 2022, Cisco Systems, Inc. 2214 1197_05_2022_c2 PIMSM SPT Switchover Receiver RP Source Source Tree Shared Tree (S, G) Traffic flow is now only flowing to the Receiver via a single branch of the Source Tree. Traffic Flow 84 169。 2022, Cisco Systems, Inc. 2214 1197_05_2022_c2 PIMSM FFF The default behavior of PIMSM in Cisco IOS is that routers with directly connected members will join the Shortest Path Tree as soon as they detect a new multicast source. PIMSM Frequently Fotten Fact 85 169。 2022, Cisco Systems, Inc. 2214 1197_05_2022_c2 PIMSM—Evaluation ? Effective for sparse or dense distribution of multicast receivers ? Advantages: – Traffic only sent down ―joined‖ branches – Can switch to optimal sourcetrees for high traffic sources dynamically – Unicast routing protocolindependent – Basis for interdomain multicast routing ?When used with MBGP and MSDP 86 169。 2022, Cisco Systems, Inc. 2214 1197_05_2022_c2 Other Multicast Protocols ? Academic worksinprogress ? Run primarily on MS Power Point 87 169。 2022, Cisco Systems, Inc. 2214 1197_05_2022_c2 Documentation and Contact Info ?EFT/Beta Site Web Page: ?TAC Support Mailing List: ?Customer Support Mailing List: 88 169。 2022, Cisco Systems, Inc. 2214 1197_05_2022_c2 If All Else Fails—RTFB1 1 Read this fine book Introduction to IP Multicast Session 2214 89 169。 2022, Cisco Systems, Inc. 2214 1197_05_2022_c2 Please Complete Your Evaluation Form Session 2214 90 169。 2022, Cisco Systems, Inc. 2214 1197_05_2022_c2 91 169。 2022, Cisco Systems, Inc. 2214 1197_05_2022_c2