Revisiting hierarchical quorum systems

In distributed systems, it is often necessary to provide coordination among the multiple concurrent processes. Quorum systems provide a decentralized approach to provide such coordination that is resilient to node and communication link failures. Quorum systems are highly available and may be used to balance the load among the elements of the system. In this paper, we propose a modification to the hierarchical grid quorum system that leads to a smaller quorum size and better availability and load. We also propose a new hierarchical quorum construction based on the organization of elements in a triangular shape that presents better average quorum size, availability and load than other highly-available systems with almost optimal load