IMT Institute for Advanced Studies , Lucca Lucca , Italy

In the last decade many studies have exploited the BGP data provided by route collector projects to infer an Internet ASlevel topology to perform several analyses, from discovering its graph properties to assessing its impact on the effectiveness of worm-containment strategies. Nevertheless, the topology that can be extracted from this data is far from being complete, i.e. from this data it is not possible to infer all the AS connections which actually exist among ASes. This thesis analyses the available data and investigates the contribution of route collectors in terms of AS-level connectivity by taking into account economic and geographic characteristics of the Internet AS-level ecosystem. By leveraging on a new metric, named p2c-distance, this analysis shows that the largest amount of ASes currently connected to a route collector belongs to the Internet core, thus the collected data is highly biased and is missing a lot of connections established in the Internet periphery. To address this problem, it should be increased the amount of ASes participating to a route collector project. To this end, this thesis describes how to improve the coverage of route collectors by means of an optimization problem based on the p2c-distancemetric, which solution quantifies the minimum number of ASes that should join a route collector in order to obtain an Internet AS-level topology as complete as possible. The results show that route collectors are rarely connected to the selected ASes, highlighting that much effort is needed to devise an ideal route collector infrastructure that would be able to capture a complete view of the Internet.