The co-modality is a new notion introduced by the European commission in 2006. It consists on developing infrastructures and taking measures and actions that will ensure optimum combination of individual transport modes enabling them to be combined effectively in terms of economic, environmental, service and financial efficiency, etc. Including different transport services in one system means that this one must cope with different distributed transport information stored in different location. For these reasons, we propose in this paper a distributed architecture that aims to satisfy transport users by providing them an optimized co-modal itineraries taking in account their constraints and preferences.