Forwarding State Reduction for Multi-Tree Multicast in Software Defined Networks using Bloom Filters.

In this work we present a novel technique for multicast route encoding in SDN using bloom filters and a minimally extended version of OpenFlow. We demonstrate that this technique allows multiple trees to be installed into the network for each multicast group without any overhead in flow table size, thereby significantly improving the forwarding state scalability of multi-tree traffic engineering in SDN. We implement and evaluate this technique using both flow level network simulation and packet level network emulation with Mininet. We demonstrate that the application of our technique imposes only a modest increase in flow setup time, that is on the same order as typical IPTV channel zapping times, and we present several variations of bloom filter construction technique that allow this flow setup time disadvantage to be further mitigated.