Towards an Accurate AS-Level Traceroute Tool

Zhuoqing Morley Mao, Jennifer L. Rexford, Jia Wang, Randy H. Katz

Research output: Contribution to journalConference articlepeer-review

107 Scopus citations


Traceroute is widely used to detect routing problems, characterize end-to-end paths, and discover the Internet topology. Providing an accurate list of the Autonomous Systems (ASes) along the forwarding path would make traceroute even more valuable to researchers and network operators. However, conventional approaches to mapping traceroute hops to AS numbers are not accurate enough. Address registries are often incomplete and out-of-date. BGP routing tables provide a better IP-to-AS mapping, though this approach has significant limitations as well. Based on our extensive measurements, about 10% of the traceroute paths have one or more hops that do not map to a unique AS number, and around 15% of the traceroute AS paths have an AS loop. In addition, some traceroute AS paths have extra or missing AS hops due to Internet exchange Points, sibling ASes managed by the same institution, and ASes that do not advertise routes to their infrastructure. Using the BGP tables as a starting point, we propose techniques for improving the IP-to-AS mapping as an important step toward an AS-level traceroute tool. Our algorithms draw on analysis of traceroute probes, reverse DNS lookups, BGP routing tables, and BGP update messages collected from multiple locations. We also discuss how the improved IP-to-AS mapping allows us to home in on cases where the BGP and traceroute AS paths differ for legitimate reasons.

Original languageEnglish (US)
Pages (from-to)365-378
Number of pages14
JournalComputer Communication Review
Issue number4
StatePublished - Oct 2003
EventProceedings of ACM SIGCOMM 2003: Conference on Computer Communications - Karlsruhe, Germany
Duration: Aug 25 2003Aug 29 2003

All Science Journal Classification (ASJC) codes

  • Software
  • Computer Networks and Communications


  • AS-level path
  • Border Gateway Protocol
  • Internet topology
  • Network measurements


Dive into the research topics of 'Towards an Accurate AS-Level Traceroute Tool'. Together they form a unique fingerprint.

Cite this