US Patent 10567187 Methods to optimize multicast routing in overlay networks

The disclosure provides an approach for reducing multicast traffic within a network by optimizing placement of virtual machines within subnets and within hosts, and by optimizing mapping of overlay multicast groups to underlay multicast groups. In one embodiment, substantially all VMs of a multicast group are migrated to the same subnet of the network. Thereafter or independently, VMs in the same subnet are migrated to the same host, ideally to the subnet proxy endpoint of that subnet. In the same or in another embodiment, if multiple overlay groups map to the same underlay group, one or more of the overlay groups may be remapped to a separate underlay group to improve network performance.