This paper considers recent contributions concerning metallic structures designed to stop rockfalls. These structures are composed of metallic nets made with Anti-Sub-Marin (ASM) rings. A constitutive modelling in finite strains of these nets is presented. The proposed modelling is based both on experimental and analytical approaches. The local behavior of the net (the ASM rings) is described in the usual framework of elasto-plasticity. This research has led to the development of an original computational software, whose goals are both industrial and academic. Thus, in order to give a clear indication of the capacity of both modelling and computational software, an example of simulation is proposed.