A first measurement with BGP egress peer engineering

Nakamura, Ryo Shimizu, Kazuki Kamata, Teppei Pelsser, Cristel [UCL]

This paper reports on measuring the effect of engineering egress traffic to peering ASes using Segment Routing, called BGP-EPE. BGP-EPE can send packets destined to arbitrary prefixes to arbitrary eBGP peers regardless of the BGP path selection. This ability enables us to measure external connectivity from a single AS in various perspectives; for example, does the use of paths other than the BGP best paths improve performance? We conducted an experiment to measure latency to the Internet from an event network, Interop Tokyo ShowNet, where SR-MPLS and BGP-EPE were deployed. Our findings from the experiment show BGP-EPE improves latency for 77% of target prefixes, and peering provides shorter latency than transit. We further show factors on which the degree of improvement depends, e.g., the performance-obliviousness of BGP and the presence of remote peering. Also, we find 91% of peer ASes forwarded packets towards prefixes that the peers did not advertise.