Titre: Software Defined Network Research Challenges Résumé: SDN (Software Defined Network) was recently positioned by Gartner second among the top IT trends in the next five years. SDN received a huge amount of interest from traditional manufacturers (CISCO, Juniper, HP, etc.) and network operators (Google, Verizon, Yahoo) who have started building they own SDN equipments. SDN proposes a new network architecture pushing new abstractions over the network such as a clear separation between the Control Plane and the Data Plane. In this presentation, we first examine key technical aspects of the SDN architecture, such as flow processing, forwarding model, isolation, resource allocation, scalable control plane, etc. With our Industrial partners, we have developed in 2010 a new 100 Gigabps SDN switch featuring some important virtualisation services. In order to realize this SDN switch, a combination of multiple effective mathematical decomposition approaches have been investigated. These approaches are based on Game Theory, Stochastic Optimization, Control Theory, and Network Calculus Theory.