Calypso's Voyage: Charting Traceroute Paths to Submarine Cables#

Authors: Caleb Wang, Ying Zhang, Qianli Dong, Esteban Carisimo (Northwestern University), Ramakrishnan Durairajan (University of Oregon), Fabian Bustamante (Northwestern University)

• Why: Submarine cables are the physical substrate of every intercontinental WAN and cloud-region interconnect. Knowing which cables a path actually rides — and which cables are disproportionately stressed — is foundational to reasoning about interconnect capacity, redundancy, and geopolitical/physical risk.
• What: Calypso, a framework that maps traceroute paths to the specific submarine cables they traverse, plus Route Stress, a traceroute-derived metric estimating the relative importance of individual cables. Validated through expert validation, failure analysis, and regional case studies demonstrating SCN dependency discovery. (from abstract only)
• How: Integrates cable ownership records, routing metadata, and geographic constraints to infer cable usage despite the opacity of the submarine cable network — handling complications like route virtualization and inland infrastructure before/after landing points.
• Where applicable: Research and policy tool rather than an operational one; inference-based, so its accuracy is bounded by public ownership/routing data. Directly useful for WAN/interconnect planners assessing which cable systems their traffic depends on and for resilience studies.