This paper was the first to democratize the important problem of traffic matrices estimation to the networking community. These matrices are fundamental quantities for network operators that characterize the traffic demand entering into a network. Nevertheless measuring them in real time is a challenging problem and inference techniques have to be developed. The paper presents a comprehensive comparison between different approaches and to give directions that were thereafter followed by more than 50 papers in the forthcoming years. The paper is nowadays one of the most cited paper in the networking area (>190 citations in google scholar). RAE_import_type : Conference contribution RAE_uoa_type : Computer Science and Informatics