, Volume 24, Issue 6, pp 299-321,
Open Access This content is freely available online to anyone, anywhere at any time.
Date: 19 Nov 2011

Consensus in the presence of mortal Byzantine faulty processes


We consider the problem of reaching agreement in distributed systems in which some processes may deviate from their prescribed behavior before they eventually crash. We call this failure model “mortal Byzantine”. After discussing some application examples where this model is justified, we provide matching upper and lower bounds on the number of faulty processes, and on the required number of rounds in synchronous systems. We then continue our study by varying different system parameters. On the one hand, we consider the failure model under weaker timing assumptions, namely for partially synchronous systems and asynchronous systems with unreliable failure detectors. On the other hand, we vary the failure model in that we limit the occurrences of faulty steps that actually lead to a crash in synchronous systems.

J. Widder was supported by the Austrian FWF National Research Network RiSE (S11403-N23), by the PROSEED project (proj.no ICT10-050) of the Vienna Science and Technology Fund, by NSF grant 0964696, and by the FWF project THETA (proj.no. P17757). M. Biely was partially supported by the Austrian BM:vit FIT-IT project TRAFT (proj.no. 812205). G. Gridling was supported by the Austrian FWF project SPAWN (proj.no. P18264) and the Austrian BM:vit FIT-IT project FAME (proj.no. 816454). The work of Sect. 4 and parts of Sect. 6 was originally presented at the 37th Annual IEEE/IFIP International Conference on Dependable Systems and Networks, DSN 2007.