Randomized Consensus: Common Coins Are not the Holy Grail! - Archive ouverte HAL Access content directly
Reports Year : 2024

Randomized Consensus: Common Coins Are not the Holy Grail!


This paper is on binary randomized consensus in an n-process asynchronous distributed system, where each process is equipped with a binary random coin, and up to t processes may crash. Ficher, Lynch, and Paterson proved that the Consensus problem cannot be solved deterministically in such a context. It has been known since Ben-Or and Rabin in the early eighties that randomization allows solving the problem with probability 1 using round-based algorithms. Moreover, while local random binary coins may entail an exponential number of rounds in the number of processes of the system, a common coin that delivers the same random and unpredictable sequence of random binary values to all processes allows consensus algorithms that terminate within a constant average number of rounds. One may think that a common coin is The Oracle that needs to be provided for time-optimal randomized consensus. This paper studies the round complexity and the optimality of randomized consensus algorithms for different coins and different ratios n/t. For instance for n/3
No file

Dates and versions

hal-04571212 , version 1 (07-05-2024)


  • HAL Id : hal-04571212 , version 1


Achour Mostefaoui, Matthieu Perrin, Julien Weibel. Randomized Consensus: Common Coins Are not the Holy Grail!. LS2N-Nantes Université. 2024. ⟨hal-04571212⟩
0 View
0 Download


Gmail Facebook X LinkedIn More