Economic Evolution of the Internet AS-Level Ecosystem

We seek a simple model that describes how market forces acting on rational players result in the evolution of the multi-faceted topology of the Internet that we see today. We model the system based on two levels of dynamic engagement of players—at the global level with clusters of ASs operating in fixed regions, and at the regional level where each AS tries to make appropriate decisions to increase its sphere of influence. Regions appear on the map at a rate based on global market conditions. The economic relationships between two regions are decided by the dominant ASs in that region. Within each region, ASs appear at a rate based on the economy of the region. The relationships between these ASs follow from the economics of connectivity within the region. We show that this two-level model naturally produces a topology similar to the current AS-level topology. Based on measured economic details, the model explains both the observed power-law node degree distribution and the exact value of the power-law exponent γ ∼ 2.2. Using our model, we also demonstrate that topological awareness of Internet players naturally leads to consolidation of providers over time, unless some exogenous force interferes. We validate our model using historical and current measurements from BGP routing tables.