In any Ethernet system it is important to have a high availability in case of failure of any link or node. The most common value of availability is 99.9% or “three nines”. In this technical project several Ethernet systems have been designed, composed of six switches, three of them masters and three redundant, for each master switch. The traffic between user and server within the Local Area Network flows in real time. The provided services are mainly voice over IP and videoconference. The network simulator OPNET Modeler 14 was used to simulate the designed systems and to implement layer 2 protocols (data link level), in particular Rapid Spanning Tree Protocol and Link Aggregation Control Protocol. An optimal system was found after modifying some parameters of those protocols that are available in the software. The optimal system significantly reduces the convergence time in case of a breakdown of any device in the network. Finally, the optimal system is compared to the results obtained from a real system. Before performing this comparison the obtained results from the simulator were validated.