In this article, we present Medpeer, a new peer-to-peer (P2P) management system for heterogeneous and distributed data sources. Its principal goal is to provide necessary tools for the semantic mediation of data from various types (relational, image, text,..) and for the semantic routing of multimodal queries in an P2P environment. In this environment, each peer will be able to publish the data he wants to share, he is completely autonomous and the data can belong to different models. MedPeer is a Super-Peer system where the super-peers are organized by type of data and contain an ontological structure specific to each type. Each peer exports their data in a common format in the form of a semantically rich ontology in order to contribute to schemas reconciliation. The queries exchanged have a common format in the form of XML documents, and are routed towards the relevant peers thanks to a semantic topology built on top of the existing physical topology