Galileo to be the first GNSS to offer authentication service worldwide with launch of OSNMA

EUSPA today announced the forthcoming official launch of the Galileo Open Service – Navigation Message Authentication (OSNMA), a new authentication mechanism that lets OS users verify the authenticity of the data used for the GNSS positioning and timing on 24 July.

Coming at a time when attacks on GNSS signals, such as spoofing, are on the rise, OSNMA provides a critical layer of protection. Spoofing involves the transmission of counterfeit satellite signals that deceive GNSS receivers, potentially resulting in false and unreliable positioning. These events can affect critical applications in transportation, finance, telecommunications, information technology, energy, utilities, manufacturing, health services, emergency services and law enforcement, in which GNSS, and in particular Galileo, is used. In sectors such as aviation or maritime, this can lead to serious safety risks.

The Galileo OSNMA mitigates these threats by allowing users to confirm that the data they receive is genuinely from Galileo and has not been tampered with. It works by embedding cryptographic data, or a digital signature, into the navigation message (I/NAV) broadcast on the E1-B signal.
Because the OSNMA is transmitted in the Galileo Open Service signal, which is already used in most devices, receivers only need to implement the protocol and download the certified public keys from the European GNSS Service Centre (GSC) website. OSNMA service relies as well on the implementation of dedicated logic on the receiver side to guarantee the end-to-end authentication process. The service does not require the storage and management of secret keys on the user side, which facilitates the adoption in different communities. Importantly, the OSNMA mechanism does not alter Galileo’s existing signal structure, ensuring that Open Service navigation performance remains unaffected.

While OSNMA does not prevent spoofing or jamming, it makes spoofing significantly harder by authenticating the data and making the Galileo signal unpredictable and harder to replicate. It also enhances the system’s resilience, giving users an important tool in detecting and responding to threats.

“Stakeholders have clearly articulated a need for more robust GNSS services. The Galileo OSNMA delivers this robustness and, in doing so, provides enhanced security in positioning and timing solutions.“ Rodrigo DA COSTA, EUSPA Executive Director

“The OSNMA Initial Service declaration has been authorised by the EU Space SAB following independent security checks and cooperation with the Programme to define risk mitigation measures. The cooperation between the SAB, the Commission and EUSPA was instrumental to getting through this very important milestone.” Philippe BERTRAND, EU Space Security Accreditation Chair

The launch of Galileo OSNMA marks another milestone in the EU’s commitment to secure and reliable space-based services.

The OSNMA declaration of service follows an extensive testing phase in which GNSS manufacturers, integrators, and application developers assessed the service across diverse scenarios using the Signal in Space (SiS). With this launch, Galileo becomes the first GNSS in the world to offer authentication globally as part of its Open Service — a major step in reinforcing Europe’s leadership in secure satellite navigation.

The OSNMA is provided by EUSPA, the operational service provider for Galileo.