Measuring ISP
Topologies with Rocketfuel. To date, realistic ISP topologies have not been accessible
to the research community, leaving work that depends on topology on an
uncertain footing. In this paper, we
present new Internet mapping techniques that have enabled us to directly
measure router-level ISP topologies.
Our techniques reduce the number of required traces compared to a brute-force,
all-to-all approach by three orders of magnitude without a significant loss
in accuracy. They include the use of BGP
routing tables to focus the measurements, exploiting properties of IP routing
to eliminate redundant measurements, better alias resolution, and the use of
DNS to divide each map into POPs and backbone. We
collect maps from ten diverse ISPs using our techniques, and find that our
maps are substantially more complete than those of earlier Internet mapping
efforts. We also report on properties of these maps, including the size of POPs, distribution of router outdegree,
and the inter-domain peering structure.
As part of this work, we release our maps to the community. Papers are provided as
a service to all by the members of ACM SIGCOMM. This
paper is available in Adobe PDF format. |