RS-API - Accept announcments as legit as possible#

Evann Dreumont and Alarig Le Lay, Breizh-IX

• Why: Route-server filter generation is a solved-looking problem that isn't: PeeringDB max-pref values are self-reported and unreliable, and an AS-SET can quietly pull in hundreds of thousands of prefixes (one shown bgpq4 expansion: 202,416). This is adoptable open-source tooling that confronts registry data with observed reality.
• What: RS-API, a caching proxy around bgpq4, bgp.tools and bgproutes.io that generates route-server configuration: RPKI (ROA + ASPA), OTC checks (RFC 9234), bogon and specificity filters, IRR prefix-lists, and a recomputed max-pref derived from the peer's actual AS cone rather than their PeeringDB claim, with AMS-IX-style scaling applied.
• How: JSON API with a 24-hour TTL cache (config generation across 2 route servers × 4 cities would otherwise hammer the upstream APIs); AS-cone sizing via the bgp.tools API with a bgproutes.io looking-glass fallback; deployed in production at Breizh-IX (Rennes, Nantes, Lille, Strasbourg); open source.
• Where applicable: Any IXP route server, especially small and medium ones; it depends on third-party APIs (bgp.tools, bgproutes.io) being available and accurate — the talk explicitly asks larger IXPs how they solve the same problem.