I started studying Internet topologies at the AS level of abstraction in March 2009 during my Master Degree thesis. I began with studying public Internet topologies provided by CAIDA (The Cooperative Association for Internet Data Analysis), IRL (UCLA Internet Research Lab) and DIMES Project. Then I focused on the analysis of the properties of the Internet graph in different geographical regions with particular attention at the role of public peering (i.e. peering at IXPs).

In my first year ofthe Ph.D. program I studied the structural characteristics ofthe Internet topology by means of community detection algorithms. k-core decomposition [COMCOM], k-dense method [COMSNETS] and k-clique percolation method [ISCIS, SIMPLEX, INFQ] enabled us to find the densest sub-graphs of the Internet topology. The analyses showed that the most well-connected communities consist of a small number of ASs characterized by a high level of clusterization, although they tend to direct a lot of their connections to ASs outside the community. In addition these communities are mainly composed of ASs that participate at the IXPs and have a worldwide geographical scope.

I am visiting-grad at CAIDA (The Cooperative Association for Internet Data Analysis) since October 2011 where I am currently working on dk-graphs.

Here is a list of my publications:

[COMCOM] E.Gregori, A.Improta, L.Lenzini, and C.Orsini, “The impact of IXPs on the AS-level topology structure of the Internet,” Computer Communications, vol. 34, no. 1, pp. 68 – 82, 2011. 

[COMSNETS]E. Gregori, L. Lenzini, C. Orsini, “k-dense Communities in the Internet AS-Level Topology”, in: COMSNETS 2011: Proceeding of the Third International Conference on COMmunication Systems and NETworkS, Bangalore, 2011.

[SIMPLEX] E. Gregori, L. Lenzini, and C. Orsini, “k-clique Communities in the Internet AS-Level Topology Graph”, in SIMPLEX 2011: 3rd Annual Workshop on Simplifying Complex Networks for Practitioners, Minneapolis, 2011.

[ISCIS] E. Gregori, L. Lenzini, S. Mainardi, and C. Orsini, “Fast Lightweight Parallel Clique Percolation Method”, in ISCIS: 6th International Symposium on Computer and Information Sciences, London, 2011.

[INFQ] E. Gregori, L. Lenzini, and C. Orsini, “k-clique Communities and Economic Relationships in the Internet AS-level Topology Graph”, in INFQ 2011: Informatica Quantitativa, Lipari, 2011.