Nowadays, many embedded systems use specific data buses (like CAN in vehicles or MIL-STD-1553B in launchers) to ensure the exchange of data. To reduce the cost, the mass and to increase performance, a solution is to rely on a components off-the-shelf (COTS) technology. As switched Ethernet is a well-known solution and widely implemented, this technology is studied for the next generation of space launchers. In this paper, we focus on the reliability issue. In case of network components failure and without reconfiguration mechanism, the network will not carry on control data any- more. Performance of Ethernet reconfiguration solutions may be not enough efficient regarding real-time constraints. This paper aims hence at coping with real-time guarantees of self reconfiguration for Ethernet networks, especially in the space launchers. An experimental evaluation has been leaded on a real case study during a Centre National d'Etudes Spatiales (CNES) French Research & Technology (R&T) activity.