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

2026-05-07

AI Summary

This study addresses the limitations of traditional terrestrial Public Key Infrastructure (PKI) in supporting near-real-time security authentication for dense low Earth orbit (LEO) satellite constellations and multi-entity collaborative scenarios, where high latency, poor scalability, and constrained availability hinder effective operation. To overcome these challenges, this work presents the first systematic design of a space-based PKI architecture, migrating certificate management and validation functions into orbit. It proposes two complementary models: an integrated space-ground architecture and a fully autonomous in-orbit architecture, incorporating on-orbit validation authorities, autonomous space-based certificate management, and secure cross-domain coordination protocols. Analytical results demonstrate that the proposed approach substantially enhances scalability, availability, and security while reducing operational costs, thereby establishing an efficient and interoperable trust foundation for large-scale space networks.

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.

Problem

• space-based PKI
• secure space communications
• in-orbit trust services
• satellite authentication
• New Space

Innovation

• space-based PKI
• in-orbit validation
• autonomous space trust
• secure space communications
• certificate management