Business-application developers have been struggling to achieve portability between applications and disparate Software-Defined-Network (SDN) controllers. In recent years, increasing research efforts have addressed standardization of Northbound APIs (NBAPIs). However, the majority of them use closed modules at SDN single-controller architectures. Furthermore, most of state-of-the-art studies presents insufficient details as to how gathered data is treated – quite often authors do not employ strong statistical tests towards a reliable treatment of the experimental data nor consider a premise of a formal scientific experiment. In this sense, this paper presents an initial work on defining a generic NBAPI that fully adheres to Web standards to promote interoperability between applications and two popular open source controllers. A common NBAPI will give more opportunity for many small players to quickly get into the SDN application market and enables SDN app-stores to become a reality in the near future.