Anoop Ghanwani Linda Dunbar Mike McBride Vinay Bannai Ramki Krishnan Framework for Application-specific Multicast in NVO3 draft-ghanwani-nvo3-app-mcast-framework-01 Anoop Ghanwani Linda Dunbar Mike McBride Vinay Bannai Ramki Krishnan draft-ghanwani-nvo3-app-mcast-framework-01

draft-ghanwani-nvo3-app-mcast-framework-01 Overview Motivation Types of multicast traffic Mechanisms for multicast in NVO3 Impact to NVO3 control plane for supporting application-specific multicast draft-ghanwani-nvo3-app-mcast-framework-01

draft-ghanwani-nvo3-app-mcast-framework-01 Motivation Document various multicast mechanisms in NVO3 networks The NVO3 underlay may or not deploy IP multicast Highlight issues and considerations of each mechanism Discuss impact of application-specific multicast to the NVO3 control plane protocol draft-ghanwani-nvo3-app-mcast-framework-01

Types of Multicast Traffic ARP/ND Application multicast Source-specific multicast (s,G) Any-source multicast (*,G) draft-ghanwani-nvo3-app-mcast-framework-01

Mechanisms for Multicast in NVO3 No multicast Replication at the source NVE Replication at a multicast service node IP multicast in the underlay Other methods Not discussed further in this draft draft-ghanwani-nvo3-app-mcast-framework-01

draft-ghanwani-nvo3-app-mcast-framework-01 No Multicast Use an NVA to obtain end station information No ARP/ND NVE responds to ARP from the TS Network does not need to be multicast capable No good way to register non-virtualized hosts No support for multicast applications draft-ghanwani-nvo3-app-mcast-framework-01

No Multicast Control Plane Impact NVE must be configured to handle ARP Request/Reply for all hosts/VNs that it participates in L2 address learning not necessary Application multicast not supported draft-ghanwani-nvo3-app-mcast-framework-01

Replication at the Source NVE Source NVE creates copies for all destination NVEs Copies are delivered by unicast Network does not need to be multicast capable Scalability concerns Forwarding performance of NVE Redundant copies on shared links draft-ghanwani-nvo3-app-mcast-framework-01

Replication at the Source NVE Control Plane Impact NVA must configure NVE with addresses of all remote NVEs for each VNI Unknowns and multicast traffic would be sent to that set of NVEs NVE may snoop IGMP Joins to optimize multicast If this is done, then NVEs must be aware when any group member moves L2 address learning may be used draft-ghanwani-nvo3-app-mcast-framework-01

Replication at a Multicast Service Node Multicast packets are unicast to replication node Replication node creates copies and unicasts them to destination NVEs Network does not need to be multicast capable Scalability concerns Forwarding performance of replication node Redundant copies on shared links from replication node RPF / MAC address learning draft-ghanwani-nvo3-app-mcast-framework-01

Replication at MSN Control Plane Impact NVA must configure NVE to send unknown, multicast traffic to MSN in addition to local TSs MSN can optimize delivery based on knowledge of NVEs participating in a VNI and snooping IGMP messages MSN must have knowledge of VNI membership and can snoop MSN could function as IGMP querier L2 address learning cannot be used At least not without some hacks draft-ghanwani-nvo3-app-mcast-framework-01

IP Multicast in the Underlay IP multicast is used in the underlay PIM-SM BIDIR PIM IGMP/MLD Snooping Ensures optimal delivery Scalability concerns Must use a different “outer” multicast address for each tenant multicast address State in the network for multicast traffic BIER may help draft-ghanwani-nvo3-app-mcast-framework-01

IP Multicast in the Underlay Control Plane Impact NVA must configure the NVE with which undelay group address to use for each VNI To optimize multicast, a separate underlay address would be required for each tenant multicast group L2 address learning may be used draft-ghanwani-nvo3-app-mcast-framework-01

draft-ghanwani-nvo3-app-mcast-framework-01 Summary & Next Steps There are many ways to achieve multicast transport in an NVO3 network All of them have been used in different pre-standard implementations The mechanisms are described and the pros and cons of each are discussed Impact to the NVO3 control plane is discussed for each of the mechanisms Ready to become a WG document? draft-ghanwani-nvo3-app-mcast-framework-01

draft-ghanwani-nvo3-app-mcast-framework-01 Thank you draft-ghanwani-nvo3-app-mcast-framework-01