Ricardo Custódio was born in Brazil where he studied Electrical Engineering. He received a M.Sc. degree from the Federal University of Santa Catarina (Brazil) and a Ph.D. from the Federal University of Rio Grande do Sul (Brazil). He is a Professor at Federal University of Santa Catarina in Florianopolis (Brazil). His main research interests are in digital signature systems and algorithms, electronic documents, key management systems and public key infrastructure.