From Testbed to Operations: Validating Distributed Optical Ground Station Services with OPTIMUS

Kurzfassung

Optical space-to-ground communication offers high-capacity delivery of spacecraft data, but operational use across multiple ground stations remains complicated by variable link availability due to atmospheric and weather effects, heterogeneous provider interfaces and independently operated network infrastructures. The ESA-funded Optical Multi User Service (OPTIMUS) project addresses this challenge through a shared coordination and delivery layer connecting spacecraft operators, optical ground stations and external Network Operations Centres (NOCs). Building on the modular testbed architecture presented in earlier work, this paper defines an end-to-end operational concept combining link-opportunity calculation, CCSDS-based service booking, schedule confirmation, operational monitoring and Delay-/Disruption-Tolerant Networking for data delivery. Provider-specific routing, authentication and connectivity are isolated through an adaptable Gateway, while telescope and modem control remain under the authority of the participating ground stations. A progressive validation methodology is applied across externally operated, implemented and emulated elements. Preliminary integration includes Service Package Request and Simple Schedule exchange with an external NOC for two participating stations, controlled service-management interfaces and terrestrial bundle routing through a DTN environment using PIGEON, ESA's BP implementation. CFDP transfers using 10 MB and 100 MB test files were completed with matching transmitted and received file sizes and checksums. Representative stream-oriented traffic and continued forwarding following controlled connectivity interruptions were also demonstrated. These tests address functional routing, integrity and disruption handling rather than throughput and scalability. The results provide preliminary evidence that a pragmatic combination of standardised service-management products, adaptable provider integration and DTN-based delivery can support the federation of heterogeneous optical groundstation resources. Physical optical-data reception, direct modem integration and operational multi-station delivery remain subjects of the next validation stage.