His first research was done in the area of formal description techniques. From 1989 to 1994 he was deeply involved in the design, installation, management and evolution of the Spanish academic network. Since 1992 he has participated in R&D tasks related to distributed applications and computer-supported cooperative work over personal computers and broadband networks, being involved in several national and international research projects like Co-Learn (Delta), EDUBA (PlanBa) and LEVERAGE (ACTS). More recently, he has been involved in research projects around Internet QoS and IPv6, especially, he was involved in BTI project (ACTS), designing and developing protocols to support IntServ QoS over multicast access networks.