An Info Note has been published with analytical information on the Galileo Open Service – Navigation Message Authentication (OSNMA). The note is available on the European Union Agency for the Space Programme (EUSPA) website or through the European GNSS Service Centre. To contribute to the detection of GNSS jamming and spoofing attacks, EUSPA together with the European Commission is testing OSNMA.
This forthcoming service is an authentication mechanism that allows Open Service users to verify the authenticity of GNSS information, making sure that the data they receive is indeed from Galileo and has not been modified in any way.
OSNMA is authenticating data for geolocation information from the Open Service through the Navigation Message (I/NAV) broadcast on the E1-B signal component. This is realized by transmitting authentication-specific data in previously reserved fields of the E1 I/NAV message. By using these previously reserved fields, OSNMA does not introduce any overlay to the system, thus the OS navigation performance remains untouched.
Authentication is set to further strengthen service robustness by increasing the capability of detecting spoofing events. However, it should be kept in mind that authentication does not prevent the occurrence of such an event, and does not protect against jamming. Nonetheless, this added layer of protection proposes to be one step ahead of evolving technological trends by amplifying the service’s overall robustness and resilience.