The Service Definition Document presents the characteristics and terms and condition of use of the services offered to users by the EGNOS Safety of Life (SoL).
 
The EGNOS Safety of Life (SoL) Service is provided openly and is freely accessible without any direct charge, and is tailored to safety-critical transport applications in various domains, in particular for aviation applications.

The major improvement of this new SDD is the enlargement of the EGNOS service area, as shown below for the APV-I availability.

EGNOS (the European Geostationary Navigation Overlay Service) is the European Satellite-Based Augmentation System (SBAS) that complements the GPS system to improve the accuracy and provides integrity to the signal over most of Europe.
It is Europe's first venture into satellite navigation and a major stepping-stone towards Galileo, Europe's own global satellite navigation system for the future.

ESSP was founded in 2009 by the Air navigation services providers from France (DGAC/DSNA), Germany (DFS), Italy (ENAV)), Portugal (NAV-P), Spain (Aena), Switzerland (skyguide) and UK (NATS) and has for mission the provision of the Safety of Life (SoL) Service, compliant with ICAO SBAS standards and recommended practices throughout the European Civil Aviation Conference (ECAC) Region, the EGNOS Open Service (OS) and the EDAS Service (EGNOS Data Access Service).