VDL Mode 4 - CNS Aviation Network

The Communication, Navigation and Surveillance (CNS) Network enables data to be transferred between mobile users and ground-based local or remote users.

The data is transferred using standardized formats and structures:
     - Wired data transfer – TCP/IP
     - Wireless data transfer – VDL Mode 4

The CNS Network supports various system alternatives and customized solutions. System solutions can focus on different applications while using the same basic services.

Examples of system solutions include applications at airports (A-SMGCS and ground handling), 4-Dimensional Trajectory (4DT), time-based ATM, green approach (A-CDA), off-shore (e.g. oilrigs), and in SAR operations.

The CNS Network can support systems in which functions such as surveillance, navigation, communication, and real-time transfer of data are required. Such systems can be interconnected to form a wide area network that enables long-distance communication with mobile users and data collection from remote or distant locations.


The CNS Network supports airborne and ground users with services such as:
     - ADS-B -Automatic Dependent Surveillance – Broadcast, providing a complete surveillance picture.
     - GNS-B- Differential GNSS augmentation Broadcast, for enhanced position accuracy and integrity.
     FIS-B - Flight Information Service Broadcast, providing weather and ATC information.
     - TIS-B - Traffic Information Service-Broadcast, an uplink of targets from other surveillance sources.
     Point-to-point - addressed communication.