The Aeronautical Telecommunication Network^[1] (ATN) is an internetwork architecture that allows ground/ground, air/ground, and avionic data subnetworks to interoperate by adopting common interface services and protocols based on the ISO OSI Reference Model.
European part of ATN used for ground/ground communications is represented by PENS.

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de:Aeronautical Telecommunications Network sk:Leteck telekomunika n sie