dc.contributor.author Oluwasanmi, Olumuyiwa dc.date.accessioned 2012-02-01T18:28:37Z dc.date.available 2012-02-01T18:28:37Z dc.date.issued 2012-02-01 dc.date.submitted December 2011 dc.identifier.uri http://hdl.handle.net/1928/17495 dc.description.abstract With the growth of the Internet, there has been a push toward designing reliable algorithms that scale effectively in terms of latency, bandwidth and other computational resources. Scalability has been a serious problem especially with peer-to-peer (p2p) networks which may have sizes of more than a million nodes. en_US An important problem in designing reliable algorithms is Byzantine agreement. For reasons of scalability, message complexity is a critical resource for this problem. Unfortunately, previous solutions to Byzantine agreement require each processor to send $O(n)$ messages, where $n$ is the total number of processors in the network. In this dissertation, we show that the Byzantine agreement problem can be solved with significantly less that a linear number of messages both in theory and in practice. We implement and test algorithms that solve the classical problem with each processor sending only $\tilde{O}(\sqrt{n})$ messages. Further, we consider the problem in the case where we assume the existence of a random beacon: a global source of random bits. We show that with this assumption, the required number of messages drops to $O(\log n)$, with small hidden constants. Our algorithms are Monte Carlo and succeed with high probability, that is probability $1-o(n^k)$ for some positive constant $k$. Our empirical results suggest that our algorithms may outperform classical solutions to Byzantine agreement for network of size larger than 30,000 nodes. dc.description.sponsorship NSF, AFOSR MURI Grant. en_US dc.language.iso en_US en_US dc.subject Byzantine Agreement en_US dc.subject Fault-Tolerant en_US dc.subject Fault-Tolerance en_US dc.subject Randomized Algorithm en_US dc.subject Monte Carlo en_US dc.subject Random Beacon en_US dc.subject Distributed Algorithm en_US dc.subject Consensus en_US dc.subject Byzantine en_US dc.subject.lcsh Computer networks--Scalability. dc.subject.lcsh Fault-tolerant computing. dc.subject.lcsh Computer algorithms. dc.title Practical, scalable algorithms for Byzantine agreement en_US dc.type Dissertation en_US dc.description.degree Computer Science en_US dc.description.level Doctoral en_US dc.description.department University of New Mexico. Dept. of Computer Science en_US dc.description.advisor Saia, Jared dc.description.committee-member Bridges, Patrick dc.description.committee-member Moore, Cristopher dc.description.committee-member Valerie, King
﻿

### This item appears in the following Collection(s)

University Libraries
MSC05 3020
1 University of New Mexico
Albuquerque NM 87131
505.277.9100