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PIM Snooping in VPLS draft-hemige-serbest-l2vpn-vpls-pim-snooping-00.txt. Suresh Boddapati Venu Hemige Sunil Khandekar Vach Kompella Marc Lasserre Rob Nath Ray Qiu Yetik Serbest Himanshu Shah. Background . WG consensus from last IETF – split VPLS Multicast into :
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PIM Snooping in VPLSdraft-hemige-serbest-l2vpn-vpls-pim-snooping-00.txt Suresh Boddapati Venu Hemige Sunil Khandekar Vach Kompella Marc Lasserre Rob Nath Ray Qiu Yetik Serbest Himanshu Shah
Background • WG consensus from last IETF – split VPLS Multicast into : • Mcast Trees in Provider Core (draft-raggarwa-l2vpn-vpls-mcast) • IGMP-Snooping (draft-ietf-magma-snoop-12.txt ) • PIM-Snooping in VPLS • PE-to-PE Mcast State Distribution • Split draft-serbest-l2vpn-vpls-mcast-03 into: • PIM-Snooping in VPLS (This draft) • PE-to-PE Mcast State Distribution in VPLS using LDP
PIM Snooping in VPLS • VPLS floods mcast traffic today. • PIM-Snooping prevents unwanted mcast traffic • Issue A of the Requirements Draft. • PIM Snooping on ACs. • Defines data forwarding rules for IGMP+PIM. • Requires CEs to disable PIM Join-Suppression. • For PWs, PEs learn PIM states using: • PIM Snooping OR • Via LDP.
What changed from draft-serbest-l2vpn-vpls-mcast-03? • Removed IGMP-Snooping • Updated PIM-Snooping procedures. • Requires CEs to disable PIM Join Suppression. • PIM Join/Prunes are flooded in VPLS. • LDP procedures moved to draft-qiu-serbest-l2vpn-vpls-mcast-ldp-00. • Modified procedures for duplicate traffic.
PIM-Snooping Basic Example R2 R1 PE2 PE1 Joins flooded. Only PEs towards RPF build state Traffic sent only on interested ports PE3 PW AC Join to RPF Nbr Join seen Data Traffic R4 R3
Duplicate Traffic Scenario R2 R1 PE2 PE1 Duplicate traffic to both R3 and R4 PE3 PW AC Join to RPF Nbr Join seen Data Traffic R4 R3
Assert Mechanism in VPLS PIM-Snooping • Constraint: Split-Horizon rules require traffic ingressing on PW to not egress on PW. • Facilitate traffic to reach the routers forwarding traffic. • Results in Assert between the routers. • Two rules facilitate this: • Add incoming port to outgoing-port-list • When Join is “seen”, add PW towards RPF-neighbor to outgoing-port-list
Assert Mechanism in VPLS PIM-Snooping R2 R1 AC1 PIM ASSERT PE2 PE1 1. A PE snooping a Join(S,G) adds IIF and OIF to OIF-List. 2. A PE “seeing” a Join, adds the PW to the RPF-nbr to the OIF-List PW12 PE3 PW AC Join to RPF Nbr Join seen Data Traffic Assert Winner becomes the forwarder in the VPLS R4 R3
Summary • PIM-Snooping is important to make VPLS Multicast work. • There is a lot of interest in solving the issue addressed by this draft. • WG document.