On the impact of layer-2 on node degree distribution

The Internet topology data collected through traceroute exploration has been extensively studied in the past. In particular, a remarkable property of the Internet, the power-law shape of node degree distribution, drew the attention of the research community. Several studies have since questioned this property. In this paper, based on a large dataset collected using mrinfo, we show that the node degree distribution is strongly impacted by the presence of layer-2 (L2) networks, such as switches. L2 devices interconnect a large number of routers, themselves being also involved in multiple L2 interconnections. Such a situation induces nodes with very high degree when analyzing the layer-3 (L3) graph with traceroute probing. Considering the physical design of a network, our analysis provides a lower bound on the bias generated by using only an L3 view. We also provide a model that can be a first step towards L2 aware topology generation. Categories and Subject Descriptors C.2.1 [Network Ar...

• Type: Journal
• Year: 2010
• Where: IMC
• Authors: Pascal Mérindol, Benoit Donnet, Olivier Bonaventure, Jean-Jacques Pansiot
• Keywords: IMC 2010, Internet Technology, Network Topology, Node Degree Distribution, Topology