Popis: |
How pervasive is the vulnerability to linkflooding attacks that degrade connectivity of thousands of Internet hosts? Are some network topologies and geographic regions more vulnerable than others? Do practical countermeasures exist? To answer these questions, we introduce the notion of the routing bottlenecks and show that it is a fundamental property of Internet design; i.e., it is a consequence of route-cost minimizations. We illustrate the pervasiveness of routing bottlenecks in an experiment comprising 15 countries and 15 cities distributed around the world, and measure their susceptibility to linkflooding attacks. We present the key characteristics of routing bottlenecks, including size, link type, and distance from host destinations, and suggest specific structural and operational countermeasures to linkflooding attacks. These countermeasures can be deployed by network operators without major Internet redesign. |