Description / Abstract: This document provides standards for Aeronautical Telecommunication Network functions for aircraft systems and equipment. These standards are in the form of performance criteria for ATN functions; qualification criteria for demonstrating performance requirements; descriptions of evidence that indicate that performance objectives have been satisfied. Performance objectives, qualification and evidence are discussed as they relate to satisfying the requirements for airworthiness approval of ATN functions. The functions covered by the MOPS can be incorporated in a wide variety of hardware configurations onboard an aircraft. Section 2 of the document expresses the requirements for airborne ATN systems. Section 3 describes the means of qualification by providing an overview of the testing process and listing detailed tests.