Network Fault Model for Dependability Assessment of Networked Embedded Systems

This paper presents a network-based fault model for dependability assessment of distributed applications built over networked embedded systems. This fault model represents global failures in terms of wrong behavior of packet-based asynchronous data transmissions. Packets are subject to different faults, i.e., drop, cut, bit errors, and duplication; these events can model either HW/SW failures of the networked embedded systems or problems in the channel among them. The paper describes 1) the proposed fault model in relation with existing ones, 2) its possible application scenarios, and 3) a SystemC tool for the simulation of both fault-free and faulty wireless sensor networks. Experimental results show the validity of the approach in the verification of communication protocols and its support to determine the optimal number of nodes in a wireless sensor network based on the IEEE 802.15.4 standard. Part of the software is available at http://sourceforge.net/projects/scnsl/.