SDN based implementation of publish/subscribe paradigm using OpenFlow multicast

In the traditional Publish/Subscribe (Pub/Sub) paradigm, most of the responsibilities lie with the broker, thus making it burdened. It also takes a considerable amount of time to first route the publications and subscriptions towards the broker, and then to further route the notifications to the subscribers. This leads to delays in data delivery. Besides delay and bandwidth consumption, the number of flows installed on a Ternary Content-Addressable Memory (TCAM) switch is another important factor to be considered for better QoS (Quality of Service). Software Defined Networking (SDN) has evolved as a new networking paradigm, in which the data plane and the control plane decoupled from each other. This decoupling nature of SDN can be used to reduce the burden on the broker. In this work, we have proposed an SDN based implementation of multicast in Pub/Sub based networks to reduce delay, the false positive rates and the flow table size, thus improving the QoS. It also helps in reducing the extra cost involved in the traditional method of multicasting, wherein extra-multicast switches are employed and IPv6 multicast addresses are used.