Asynchrony and Collusion in the N-party BAR Transfer Problem

TL;DR

This paper introduces an asynchronous algorithm for the N-party BAR Transfer problem that maintains data transfer reliability and Nash equilibrium properties, even in the presence of collusion among rational processes.

Contribution

It presents the first asynchronous NBART algorithm that tolerates collusion, extending previous synchronous solutions with game-theoretic analysis.

Findings

Algorithm achieves reliable data transfer in asynchronous settings.

Tolerates certain levels of collusion among rational processes.

Maintains Nash equilibrium properties under collusion.

Abstract

The problem of reliably transferring data from a set of $N_P$ producers to a set of $N_C$ consumers in the BAR model, named N-party BAR Transfer (NBART), is an important building block for volunteer computing systems. An algorithm to solve this problem in synchronous systems, which provides a Nash equilibrium, has been presented in previous work. In this paper, we propose an NBART algorithm for asynchronous systems. Furthermore, we also address the possibility of collusion among the Rational processes. Our game theoretic analysis shows that the proposed algorithm tolerates certain degree of arbitrary collusion, while still fulfilling the NBART properties.