avionics full duplex switched Ethernet (AFDX)
Avionics Full Duplex Switched Ethernet (AFDX) is a communication protocol that operates in real-time Ethernet and is used in the aircraft industry.
Flight systems communicate with each other via the standardized AFDX protocol. Since automotive and avionics technology can only work with fixed delay times, AFDX uses a deterministic access method.
The AFDX protocol is based on Ethernet 100Base- TX, supports quality of service( QoS), operates at a data rate of 100 Mbit/s and, because of the determinable delay times, with relatively small data packets. The delay times are set via the Bandwidth Allocation Gap( BAG).
AFDX is used to implement networks in star topology in point-to-multipoint( P2MP) connections. Each system is connected to a switch in a star topology. Compatibility with previous designs is realized by virtual unidirectional links, the Virtual Links( VL), which can be switched over other transmission media.