Toward migration to SDN: Generating SDN Forwarding Rules by Decision Tree

The deployment of Software Defined Network (SDN) switches faces various challenges, one of them is to generate rules to be preloaded in the flow table for performance improvement. Since the flow tables in SDN are implemented by TCAM (ternary content-addressable memory), they have a limited capacity. On the other hand, prepopulating them with the most common rules will reduce the flow setup delay. This paper provides a method for the identification of the most suitable candidate rules by observing the existing traffic and automatic generation of OpenFlow rules that can fit in SDN tables. The rules are extracted from the decision tree build based on the observed NetFlow traffic. The experiments showed that this method can provide a compact set of rules matching most of the network traffic (no less than 98 %).