Analysis of Propagation of Regular, Extended, and Large BGP Communities

This study focuses on the analysis of propagation of Regular, Extended, and Large Communities in the Border Gateway Protocol (BGP). Once added, these communities are often intended to be transitive by default, meaning that they should be propagated from one autonomous system (AS) to the next in the propagation path of BGP Update messages. There are evolving specifications in the IETF for route leak detection, Distributed Denial of Service (DDoS) mitigation, and other applications that use these communities, and depend on the transitivity to work. Relative to prior studies, this paper attempts to significantly advance the accuracy in measurement and analysis of the propagation behavior, especially for the Regular Communities. This is accomplished by performing the measurements against known applications. This work also provides measurements of the propagation of Extended and Large Communities which have not been studied before to the best of our knowledge. These propagation measurements and analyses provide insights on whether these communities adequately propagate in the current Internet to benefit evolving applications and also whether they propagate beyond their intended scope thus reflecting poor hygiene and clutter on the Internet control plane.