This document provides guidelines for the assurance of software 
contained in non-airborne CNS/ATM systems. It is intended to be 
an interpretive guide for the application of DO-178B/ED-12B, 
Software Considerations in Airborne Systems and Equipment 
Certification, to non-airborne CNS/ATM systems. DO-178B/ED-12B 
defines a set of objectives that are recommended to establish 
assurance that airborne software has the integrity needed for 
use in a safety-related application. These objectives have been 
reviewed, and in some cases, modified for application to non-
airborne CNS/ATM systems.