the emerging challenges, like simplicity, efficiency and agility, and the new optical-empowered technologies are driving the innovation of the networking in the data center. Virtualization, Consolidation and, more generally, the Cloud oriented approach, are the pillars of the new technological wave. A few key technologies, FCoE, TRILL and OTV, are leading this evolution, fostering the development of new networking architectures, models and communication paradigms. In this scenario, both the design models and power/footprint ratios for data center are changing significantly. This work aims at presenting the state-of-the art of the different technologies driving the Data Center evolution, mainly focusing on the most novel and evolutionary issues of the networking architectures, protocols and standards.