Finding the Invisible: A Comparison of IRR Data and Routing Pathways

Abstract

The Border Gateway Protocol (BGP), the de facto standard protocol for Internet routing, only passes on the ‘best’ path for every Internet destination. As such, some connections between ISPs are entirely masked. If a network does not announce any routes of its own, the entire network could be masked as well. Internet Routing Registries (IRRs) exist to record connections among all ISPs in an attempt to combat this effect. This paper examines how prevalent this masked link/network effect is and how well documented the connections between ISPs are in the European IRR. The result is that there is a relatively small number of discrepancies when comparing the data within a source, for example the IRR data. When sources are compared with each other a much larger number is uncovered.