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Supporting IP Multicast over VPLS draft-serbest-l2vpn-vpls-mcast-01.txt. Suresh Boddapati Venu Hemige Sunil Khandekar Vach Kompella Marc Lasserre Rob Nath Ray Qiu Yetik Serbest. Multicast Traffic over VPLS. The flooding of a frame occurs when:
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Supporting IP Multicast over VPLSdraft-serbest-l2vpn-vpls-mcast-01.txt Suresh Boddapati Venu Hemige Sunil Khandekar Vach Kompella Marc Lasserre Rob Nath Ray Qiu Yetik Serbest
Multicast Traffic over VPLS • The flooding of a frame occurs when: • The destination MAC address has not been learned • The destination MAC address is a broadcast address • The destination MAC address is a multicast address • Flooding is the solution today
Problem Definition • Objective • Do not send traffic to sites without receivers • Keep core P routers stateless (Multicast) • Reduce BW waste • Constraints • In VPLS, ingress replication is required • Note: There is no layer-3 adjacency (e.g., PIM) between a CE and a PE
A Solution • IGMP and/or PIM Snooping • Basic idea: Snoop IGMP and PIM messages to determine which sites to send the traffic to • Benefits: • Prevents sending multicast traffic to sites with no members • Keeps P routers in the core stateless • Improves VPLS to support IP multicast more efficiently • SP does not need to perform the tasks to provide multicast service (e.g., running PIM, managing P-group addresses, managing multicast tunnels) • SP does not need to maintain PIM adjacencies with the customers
An Application: IPTV VSO DSLAM L2-PE Copper GigE VSO L2-PE VPLS (IGMP Snooping) L2-PE Video VHO VSO SHE IP/MPLS Backbone with MCAST Support L2-PE PE VSO Internet 20-25Mbps
An Application: Router Inter-connect with PIM L2-PE PIM Site B L2-PE VPLS (PIM Snooping) L2-PE PIM L2-PE PIM Site A L2-PE Site C
Issues Addressed in v01 • IGMP Snooping • Reports are sent to all mcast routers • MRDP, static conf, PIM Hello Snooping to learn mcast routers • Explicitly stated Holddown timer for IGMP leave • If a mcast router and a host are connected to a CE (layer-2 switch), that layer-2 switch MUST do IGMP snooping • IGMPv3 reports/leaves are elaborated and the example is updated accordingly • PIM Snooping • To avoid PIM Join Suppression, PIM Joins are forwarded to “Upstream Neighbor Address”
(S,G) Join (S,G) Join (S,G) Join (S,G) Join (S,G) Join (S,G) Join Duplicate Traffic (PIM-SSM) PE2 R3 R1 VPLS PE1 R2 Src PE3 R4
(S,G) Join (S,G) Join (S,G) Join (*,G) Join (*,G) Join (*,G) Join (*,G) Join Duplicate Traffic (PIM-SM) PE2 R3 R1 PE1 VPLS R2 Src PE3 R4 RP R5
Issues Addressed in v01 (cont.) • Proposal for Duplicate Traffic Problem • Detect it, and drop the traffic coming from the AC/PW which is not associated with “Upstream Neighbor Address” • Trigger Assert by “Flush”ing (by defining TLV) the snooping state • Directly connected sources • Need to send traffic to all mcast routers • May not happen with the current guidelines • Proposals to detect directly connected sources • ARP snooping • Static configuration • Do not allow it
Next Steps • Please comment • Requirements?