Stateless multicast switching in software defined networks

TL;DR

This paper introduces a Bloom Filter-based multicast switching method for SDN that reduces state size and avoids reactive rule insertion delays, enabling scalable multicast in modern networks.

Contribution

It presents a novel stateless multicast switching technique using Bloom Filters in SDN, improving scalability and performance over existing methods.

Findings

Significantly smaller switch state size compared to traditional mechanisms

Proactive rule insertion avoids congestion and delay issues

Effective in realistic network topologies for next-generation networks

Abstract

Multicast data delivery can significantly reduce traffic in operators' networks, but has been limited in deployment due to concerns such as the scalability of state management. This paper shows how multicast can be implemented in contemporary software defined networking (SDN) switches, with less state than existing unicast switching strategies, by utilising a Bloom Filter (BF) based switching technique. Furthermore, the proposed mechanism uses only proactive rule insertion, and thus, is not limited by congestion or delay incurred by reactive controller-aided rule insertion. We compare our solution against common switching mechanisms such as layer-2 switching and MPLS in realistic network topologies by modelling the TCAM state sizes in SDN switches. The results demonstrate that our approach has significantly smaller state size compared to existing mechanisms and thus is a multicast switching solution for next generation networks.