Unlocking Path Awareness for Legacy Applications through SCION-IP Translation in eBPF
Lars-Christian Schulz, Florian Gallrein, David Hausheer · 2024
Path-aware networking (PAN) is a novel network paradigm enabling hosts to control network path selection. PAN has been realized on Internet-scale by the SCION routing protocol. Despite the increasing adoption of SCION by ISPs, only few applications offer native SCION support. The SCION-IP Gateway (SIG) tunnels legacy IP traffic over SCION, but does not allow for interoperability with native applications. To unlock PAN for legacy IP applications while maintaining compatibility with native SCION, we introduce SCION-IP translation. We present a network stack component that uses IPv6 sockets for path aware SCION communication and implement a prototype in eBPF. The translator offers more than five times the throughput of the open-source SIG for UDP and achieves 75% of native single-threaded IP application performance.