• AS
• AS-level
• AS-level map
• Autonomous Systems
• Average neighbors degree
• Betweenness
• Betweenness centrality
• Clustering coefficient
• Degree
• Graph theory
• Internet
• Internet Exchange Points
• Internet map
• Internet map
• Internet registries
• Internet scenario
• Internet Service Providers
• Internet topology
• ISP
• IX
• IXP
• Regional Internet
• Registries
• Shortest path
• Shortest path length
• Tier 1
• Tiering
• topology

The Internet is the largest masterpiece ever created by the human race. Since its birth, it has evolved from a simple couple of nodes in the United States to a complicated set of many thousands of interconnections between networking and telecommunications companies, and it is now used by a great part of the World's population. Despite this, the Internet is still evolving and far to be stuck. One of the hottest issues discussed in the last years has been the discovery of the connections between the companies that are forming the actual Internet and their relationships. However, despite significant research activity the real topology has not yet been fully discovered and, most of all, the geographical distribution of such companies has not been fully investigated. Needless to say, having a correct model of topology of the Internet would be important, mostly to test protocols, but also to plan networks and for failure detection purposes. Moreover, the geographical distribution of the Autonomous Systems would allow to verify the robustness of the Internet in each region. Several efforts have been made so far in the research activities, but it is rare to find any work that consider them all together. This thesis attempts to analyze data collected from several of those studies in order to have a more detailed view of the real topology and, moreover, will introduce the Internet Exchange Points (IXPs) in that topology, underlining the important role that these facilities play in the Internet environment. In addition to this, a framework will also be provided to link this topology to the real World, assigning to each AS one or more geographical location, that permitted the identification of different Internet behaviors in different continents and countries, reflecting the real issues that those regions have to face (e.g. costly long-distance carriers or poverty or geographical obstacles). This thesis will analyze deeply every continent in the World and will focus mostly on European Internet, analyzing some of the most important countries in Europe and two macro-regions (European Union and post-Soviet countries). A complementary work has been developed by Chiara Orsini in "Analysis of the Internet Structure at the Autonomous System Level of Abstraction: the role of Internet Exchange Points on a worldwide scale and outside Europe" introducing the most important non-European countries, including U.S.A., Japan and Australia.