Experimental evaluation of network component crashes and trigger message omissions in the Flexible Time-Triggered Replicated Star for Ethernet

A distributed embedded system (DES) is made up of a set of computing nodes interconnected by a network. If we want the DES to continue to operate even if a subset of its network elements fail, the network must be fault-tolerant. In particular, this requires that the architecture of the network provides redundant paths between nodes and that any elements critical for the operation of the network are replicated. In the context of DES that must not only be highly reliable, but also provide sufficient flexibility to adapt to unpredictable requirement changes, the Flexible Time-Triggered Replicated Star for Ethernet (FTTRS) has been proposed. One of the core features of FTTRS is precisely its fault-tolerant network architecture. In this paper we present a proof-of-concept prototype of FTTRS and a series of fault-injection experiments. These experiments show that FTTRS can tolerate the crash of any single network element, as well as the crash of various combinations of multiple network elements. A variety of omission failures affecting the most critical FTTRS message (called the trigger message) are also tolerated.