Highly dynamic distributed computing with byzantine failures
Proceedings of the 2013 ACM symposium on Principles of distributed computing
| Hi-index | 0.00 |
We consider the problem of securely conducting a poll in synchronous dynamic networks equipped with a Public Key Infrastructure (PKI). Whereas previous distributed solutions had a communication cost of $O(n^2)$ in an $n$ nodes system, we present SPP (Secure and Private Polling), the first distributed polling protocol requiring only a communication complexity of $O(n\log^3 n)$, which we prove is near-optimal. Our protocol ensures perfect security against a computationally-bounded adversary, tolerates~$(\frac{1}{2}-\epsilon)n$ Byzantine nodes for any constant $\frac{1}{2} \epsilon 0$ (not depending on $n$), and outputs the exact value of the poll with high probability. SPP is composed of two sub-protocols, which we believe to be interesting on their own: SPP-Overlay maintains a structured overlay when nodes leave or join the network, and SPP-Computation conducts the actual poll. We validate the practicality of our approach through experimental evaluations and describe briefly two possible applications of SPP: (1) an optimal Byzantine Agreement protocol whose communication complexity is $\Theta(n\log n)$ and (2) a protocol solving an open question of King and Saia in the context of aggregation functions, namely on the feasibility of performing multiparty secure aggregations with a communication complexity of $o(n^2)$.