SRv6: Is There Anybody Out There?

Abstract: Segment routing is a modern form of source-based routing, i.e., a routing technique where all or part of the routing decision is predetermined by the source or a hop on the path. Since initial standardization efforts in 2013, segment routing seems to have garnered substantial industry and operator support. Especially segment routing over IPv6 (SRv6) is advertised as having several advantages for easy deployment and flexibility in operations in networks. Many people, however, argue that the deployment of segment routing and SRv6 in particular poses a significant security threat if not done with the utmost care. In this paper we conduct a first empirical analysis of SRv6 deployment in the Internet. First, we analyze SRv6 behavior in an emulation environment and find that different SRv6 implementations have the potential to leak information to the outside. Second, we search for signs of SRv6 deployment in publicly available route collector data, but could not find any traces. Third, we run large-scale traceroute campaigns to investigate possible SRv6 deployments. In this first empirical study on SRv6 we are unable to find traces of SRv6 deployment even for companies that claim to have it deployed in their networks. This lack of leakage might be an indication of good security practices being followed by network operators when deploying SRv6.