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M. Schwarz, K. Winkler, U. Schmid:
"Fast Consensus under Eventually Stabilizing Message Adversaries";
Report No. TUW-240061, 2015; 13 pages.

This paper is devoted to deterministic consensus in synchronous
dynamic networks with unidirectional links, which are under the control of an omniscient message adversary. Motivated by unpredictable node/system initialization times and long-lasting periods of massive transient faults, we consider message adversaries
that guarantee periods of less erratic message loss only eventually: We present a tight bound of 2D+1 for the termination time of consensus under a message adversary that eventually guarantees a single vertex-stable root component with dynamic network
diameter D, as well as a simple algorithm that matches this bound. It effectively halves the termination time 4D+1 achieved by an existing consensus algorithm, which also works under our message adversary. We also introduce a generalized, considerably stronger variant of our message adversary, and show that our new algorithm, unlike the existing one, still works correctly under it.

Directed dynamic networks, consensus, message adversaries, impossibilities, lower bounds

http://publik.tuwien.ac.at/files/PubDat_240061.pdf