ARINC 664 Part 7 (AFDX)
AFDXSection 11: Aircraft & Avionics Architecture
Definition
Avionics Full-Duplex Switched Ethernet (AFDX), defined by ARINC 664 Part 7, is a deterministic, full-duplex, switched Ethernet network for avionics data communication. AFDX uses standard Ethernet physical layer and frame format with additional mechanisms for determinism: Virtual Links (VLs) with defined bandwidth allocation, redundant network paths, frame sequencing, and integrity checking. AFDX provides guaranteed bandwidth and bounded latency for each communication flow.
Where This Shows Up
AFDX was developed by Airbus and first deployed on the A380. It is also used on the A350, A400M, Boeing 787 (as a variant), and other modern platforms. AFDX addresses the bandwidth and topology limitations of ARINC 429 by providing a switched network capable of supporting hundreds of end systems with data rates up to 100 Mbit/s per port. The key certification-relevant feature is the Virtual Link concept: each VL defines a unidirectional logical communication path with a guaranteed maximum bandwidth (Bandwidth Allocation Gap) and maximum frame size, enabling deterministic timing analysis. The redundant dual-network architecture provides fault tolerance through frame selection based on sequence numbers and integrity checks.
Primary Sources
Avionics Full-Duplex Switched Ethernet Network — defines the AFDX protocol, Virtual Link concept, redundancy management, and network configuration.
Related Terms
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