@techreport{TR-IC-05-07,
  number = {IC-05-07},
  author = {Lasaro Camargos and Fernando Pedone and Edmundo R. M. Madeira},
  title = {Optimal and Practical {WAB}-Based Consensus Algorithms},
  month = {April},
  year = {2005}, 
  institution = {Institute of Computing, University of Campinas},
  note = {In English, 17 pages.
    \par\selectlanguage{english}\textbf{Abstract}
       In this paper we introduce two new WAB-based consensus
       algorithms for the crash-recovery model. The first one,
       B*-Consensus, is resilient to up to $f<n/2$ permanent faults,
       and can solve consensus in three communication
       steps. R*-Consensus, our second algorithm, is $f<n/3$
       resilient, and can solve consensus in two communication
       steps. These algorithms are optimal with respect to the time
       complexity versus resilience tradeoff. We provide analytical
       and experimental evaluation of our algorithms, and compare them
       with Paxos, an optimal leader-election based consensus algorithm
       for the crash-recovery model.
  }
}