Time-space trade-offs in population protocols for the majority problem

Publikationstyp
Journal Article
Date Issued
2021-04
Sprache
English
Author(s)
Berenbrink, Petra  
Elsässer, Robert  
Friedetzky, Thomas  
Kaaser, Dominik 
Kling, Peter  
Radzik, Tomasz  
TORE-URI
http://hdl.handle.net/11420/15134
Journal
Distributed Computing  
Volume
34
Issue
2
Start Page
91
End Page
111
Citation
Distributed Computing 34 (2): 91-111 (2021)
Publisher DOI
10.1007/s00446-020-00385-0
Scopus ID
2-s2.0-85089031203
Publisher
Springer
Is New Version of
1805.04586
Population protocols are a model for distributed computing that is focused on simplicity and robustness. A system of n identical agents (finite state machines) performs a global task like electing a unique leader or determining the majority opinion when each agent has one of two opinions. Agents communicate in pairwise interactions with randomly assigned communication partners. Quality is measured in two ways: the number of interactions to complete the task and the number of states per agent. We present protocols for the majority problem that allow for a trade-off between these two measures. Compared to the only other trade-off result (Alistarh et al. in Proceedings of the 2015 ACM symposium on principles of distributed computing, Donostia-San Sebastián, 2015), we improve the number of interactions by almost a linear factor. Furthermore, our protocols can be made uniform (working correctly without any information on the population size n), yielding the first uniform majority protocols that stabilize in a subquadratic number of interactions.
Subjects
Distributed computing
Majority
Population protocols
Stochastic processes
DDC Class
004: Informatik