The Galileo OSNMA Internet Data Distribution (IDD) Interface Control Document (ICD) complements the OSNMA Receiver Guidelines and the OSNMA Signal in Space (SIS) ICD by providing the users with the information required to access and retrieve the cryptographic  data (Public Key and Merkle Tree). The distribution of the cryptographic data is supported by the provision of Public Key Infrastructure (PKI) certificates to ensure that the data is coming from the Galileo System. The document also includes a description of the PKI certificates and information on their use.

The European Union Agency for the Space Programme (EUSPA) together with the European Commission have published the Galileo Open Service Navigation Message Authentication (OSNMA) IDD ICD. This document focuses on the products provided via the Internet and the steps the users need to follow to retrieve the Merkle Tree (MT) and the Public Key (PK) from the interfaces provided at the GSC. Furthermore, it also explains how to retrieve and use the PKI certificates provided via the GSC interface and the EUSPA web portal in order to verify both the PK and the root node of the MT.

This document will be updated before the service declaration with the inclusion of a PKI certificate signing the Merkle Tree.

The information provided in this document along with the OSNMA SIS ICD and the OSNMA Receiver Guidelines allows the full implementation of the OSNMA protocol including the authentication of the associated chain of trust.

You can find the document in the Electronic Library of the GSC website.