Toward Space-Based Public Key Systems: Enabling Secure Space Communications through In-Orbit Trust Services

TL;DR

This paper proposes space-based PKI architectures to enable secure, real-time authentication of space assets, reducing ground dependency and improving scalability for next-generation space missions.

Contribution

It introduces two novel deployment schemes for in-orbit trust services, addressing scalability, security, and operational challenges in space communication networks.

Findings

Analyzed deployment trade-offs in multi-operator environments.

Provided baseline latency analysis for in-orbit trust management.

Proposed architectures enhance security and reduce reliance on ground infrastructure.

Abstract

The New Space era has led to a rapid increase in satellites operated by independent entities in near-Earth orbit. This shift enables richer space services but also requires secure, near-real-time coordination, making efficient authentication of space assets critical for next-generation missions. Traditional ground-dependent Public Key Infrastructure (PKI) suffers from latency and operational bottlenecks that limit scalability and availability in dynamic space environments. This paper proposes architectural designs for space-based PKI that shift certificate management and validation from ground infrastructure into space, reducing reliance on ground stations while enabling interoperability and cross-entity collaboration. Two deployment schemes are introduced: a space-ground integrated PKI with in-orbit validation authorities, and a fully autonomous space-based PKI with in-space issuance and validation. We analyze deployment trade-offs in scalability, availability, security, cost, and operational complexity in multi-operator environments. A baseline latency analysis is provided to illustrate performance implications of in-orbit trust management.