ASTM F 3742:2024

1.1 This standard is a framework-oriented guide for securing localized, broadcast-type Aircraft-to-Everything (A2X) communications without the use of real-time connected services or establishment of a session-based security association between communicating entities in the airspace. It is intended to be updated as new security risks, communications security approaches, or communication types are investigated for use or standardized in aviation. 1.2 A2X communication may be used by a variety of A2X applications, each with a unique set of constraints as well as functional and security objectives. This guide is intended to facilitate standards organizations' appropriate development of credential-based security controls to meet those objectives. Recognizing the security overhead imposed by cryptographic credentials and digital signatures, it is vital to understand the security and performance impacts on secure communications, especially in constrained Radio Frequency (RF) environments. 1.3 This guide provides, as background, security concepts related to broadcast-type point-to-point, real-time, ad hoc communications, then leverages the background in formulating recommendations on how to identify and use candidate security approaches. It is a set of guiding principles on how to develop and standardize secure A2X communications; it is not a specific solution for a specific set of application requirements. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

49.090, 49.140