• Autonomous Systems
• BGP
• Internet

The Internet is nowadays an integral part of the everyone's life, and will become even more important for future generations. Proof of that is the exponential growth of the number of people who are introduced to the network through mobile phones and smartphones and are connected 24/7. Most of them rely on the Internet even for common services, such as online personal bank accounts, or even having a videoconference with a colleague living across the ocean. However, there are only a few people who are aware of what happens to their data once sent from their own devices towards the Internet, and an even smaller number -- represented by an elite of researchers -- have an overview of the infrastructure of the real Internet. Researchers have attempted during the last years to discover details about the characteristics of the Internet in order to create a model on which it would be possible to identify and address possible weaknesses of the real network. Despite several efforts in this direction, currently no model is known to represent the Internet effectively, especially due to the lack of data and the excessive coarse granularity applied by the studies done to date. This thesis addresses both issues considering Internet as a graph whose nodes are represented by Autonomous Systems (AS) and connections are represented by logical connections between ASes. In the first instance, this thesis has the objective to provide new algorithms and heuristics for studying the Internet at a level of granularity considerably more relevant to reality, by introducing economic and geographical elements that actually limit the number of possible paths between the various ASes that data can undertake. Based on these heuristics, this thesis also provides an innovative methodology suitable to quantify the completeness of the available data to identify which ASes should be involved in the BGP data collection process as feeders in order to get a complete and real view of the core of the Internet. Although the results of this methodology highlights that current BGP route collectors are not able to obtain data regarding the vast majority of the ASes part of the core of the Internet, the situation can still be improved by creating new services and incentives to attract the ASes identified by the previous methodology and introduce them as feeders of a BGP route collector.