We present a comprehensive {traffic measurement and analysis concept}to cope with the rapid deployment of peer-to-peer multimedia applications and their overlay structures. It integrates four orthogonal dimensions:traffic measurements at the packet layer, data extraction, flow analysis and inspection of peer-to-peer overlays based on a hierarchical multi-layer modeling concept, a characterization of overlay structures by techniques and metrics of complex networks,and a statistical characterization of peer-to-peer traffic features.