Analyzing BGP Policies: Methodology and Tool
Authors:	G. Siganos M. Faloutsos
Published:	Proceedings of INFOCOM, 2004
URL:	http://www.ieee-infocom.org/2004/Papers/34_5.PDF http://www.cs.ucr.edu/~siganos/papers/Nemecis.pdf
Entry Date:	2004-06-30
Abstract:	The robustness of the Internet relies heavily on the robustness of BGP routing. BGP is the glue that holds the Internet together: it is the common language of the routers that intercon- nect networks or Autonomous Systems(AS). The robustness of BGP and our ability to manage it effectively is hampered by the limited global knowledge and lack of coordination between Autonomous Systems. One of the few efforts to develop a globally analyzable and secure Internet is the creation of the Internet Routing Registries (IRRs). IRRs provide a voluntary detailed repository of BGP policy information. The IRR effort has not reached its full potential because of two reasons: a) extracting useful information is far from trivial, and b) its accuracy of the data is uncertain. In this paper, we develop a methodology and a tool (Nemecis) to extract and infer information from IRR and validate it against BGP routing tables. In addition, using our tool, we quantify the accuracy of the information of IRR. We find that IRR has a lot of inaccuracies, but also contains significant and unique information. Finally, we show that our tool can identify and extract the correct information from IRR discarding erroneous data. In conclusion, our methodology and tool close the gap in the IRR vision for an analyzable Internet repository at the BGP level.
Datasets:	Information from 55 current IRRs was collected on June 22, 2003. RouteViews (date unknown)
Experiments:	Parse and unify 55 IRRs in Routing Policy Specification Language (RPLS) text into a relational database Infer policies and relationships from database Compare policies inferred with policies from BGP routing tables Compare relationship inferrences against Gao's algorithm on BGP routing tables
Results:	90% of policies in the IRR can be converted with no errors 82.8% of polices can be converted and are symmetric between ASes 80% of routes in RouteViews have a record in IRR that verify the route origin for 38% of ASes, all links in RouteViews are also in IRR 28% of ASes have consistent policy and are consistent with BGP routing tables, almost all from RIPE's registry. 83% match between link relationships inferred from IRR and using Gao's algorithm on BGP routing tables
References:	Compares against relationship inferrence algorithm from: L. Gao, "On inferring autonomous system relationships in the Internet," IEEE/ACM Transactions on Networking, vol. 9, pp. 733-745, December 2001.