Departmental Papers (CIS)

Date of this Version

April 2006

Document Type

Conference Paper


Copyright 2006 IEEE. Reprinted from the 9th IEEE International Symposium on Object-oriented Real-time Distributed Computing (ISORC 2006), pages: 393-399

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The Avionics Full Duplex Switched Ethernet (AFDX) has been developed to provide reliable data exchange with strong data transmission time guarantees in internal communication of the aircraft. The AFDX design is based on the principle of a switched network with physically redundant links to support availability and be tolerant to transmission and link failures in the network.

In this work, we develop a formal model of the AFDX frame management to ascertain the reliability properties of the design. To capture the precise temporal semantics, we model the system as a network of timed automata and use UPPAAL to model-check for the desired properties expressed in CTL. Our analysis indicates that the design of the AFDX frame management is vulnerable to faults such as network babbling which can trigger unwarranted system resets. We show that these problems can be alleviated by modifying the original design to include a priority queue at the receiver for storing the frames. We also suggest communicating redundant copies of the reset message to achieve tolerance to network babbling.



Date Posted: 15 August 2006

This document has been peer reviewed.