A simple conceptual model for the Internet topology

In this paper, we develop a conceptual visual model for the Internet inter-domain topology. Recently, power-laws were used to describe the topology concisely. Despite their success, the power-laws do not help us visualize the topology, ie, draw the topology on paper by hand. In this paper, we deal with the following questions: can we identify a hierarchy in the Internet; how can I represent the network in an abstract graphical way? The focus of this paper is threefold. First, we characterize nodes using three metrics of topological "importance"', which we later use to identify a sense of hierarchy. Second, we identify some new topological properties. We then find that the Internet has a highly connected core and identify layers of nodes in decreasing importance surrounding the core. Finally, we show that our observations suggest an intuitive model. The topology can be seen as a jellyfish, where the core is in the middle of the cap, and one-degree nodes form its legs.